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Selected AbstractsTolterodine causes measurable restoration of urethral sensation in women with urge urinary incontinence,,NEUROUROLOGY AND URODYNAMICS, Issue 4 2010Kimberly Kenton Abstract Introduction & Hypothesis Determine if treatment of urge incontinence with tolterodine results in changes in bladder and/or urethral sensation using Current Perception Threshold (CPT) testing. Methods Women with ,1 incontinence episode on 7-day diary were treated with 4 mg of long-acting tolterodine for 2-months. At baseline and 2-months, participants had CPT testing of the urethral and bladder at 3 frequencies 2000, 250, and 5 Hz. Baseline and post-treatment measures were compared using Wilcoxon Signed Rank Test. Results Seventeen women underwent baseline CPT testing. Four discontinued medication due to side effects and did not have repeated testing. Urethral CPT at 250 Hz was lower after treatment (median 1.3 [Interquartile range .69--2.1] and .75 [.45--1.2], p,=,.003) and at 5 Hz trended toward a significant decrease (1.1 [1--1.9] and .84 [.32--1.1], p,=,.06). Conclusions Urethral sensitivity improves after 2-months of tolterodine, suggesting it may restore urethral sensory nerves in addition to known motor effects. Neurourol. Urodynam. 29:555,557, 2010. © 2009 Wiley-Liss, Inc. [source] Comparison of Hospital Mortality With Intra-Aortic Balloon Counterpulsation Insertion Before vs After Primary Percutaneous Coronary Intervention for Cardiogenic Shock Complicating Acute Myocardial InfarctionCONGESTIVE HEART FAILURE, Issue 5 2010Scott Harris DO We hypothesized that the insertion of the IABP before primary PCI might result in better survival of patients with cardiogenic shock compared with postponing the insertion until after primary PCI. We, therefore, retrospectively studied 48 patients who had undergone primary PCI with IABP because of cardiogenic shock complicating acute myocardial infarction (26 patients received the IABP before and 22 patients after primary PCI). No significant differences were present in the baseline clinical characteristics between the 2 groups. The mean number of diseased vessels was greater in the group of patients treated with the IABP before primary PCI (2.8±0.5 vs 2.3±0.7, P=.012), but the difference in the number of treated vessels was not significant. The peak creatine kinase and creatine kinase-MB levels were lower in patients treated with the IABP before primary PCI (median, 1077; interquartile range, 438,2067 vs median, 3299; interquartile range, 695,6834; P=.047 and median, 95; interquartile range, 34,196 vs median, 192; interquartile range, 82,467; P=.048, respectively). In-hospital mortality and the overall incidence of major adverse cardiac and cerebrovascular events were significantly lower in the group of patients receiving the IABP before primary PCI (19% vs 59% and 23% vs 77%, P=.007 and P=.0004, respectively). Multivariate analysis identified renal failure (odds ratio, 15.2; 95% confidence interval, 3.13,73.66) and insertion of the IABP after PCI (odds ratio, 5.2; 95% confidence interval, 1.09,24.76) as the only independent predictors of in-hospital mortality. In conclusion, the results of the present study suggest that patients with cardiogenic shock complicating acute myocardial infarction who undergo primary PCI assisted by IABP have a more favorable in-hospital outcome and lower in-hospital mortality than patients who receive IABP after PCI. Abdel-Wahab M, Saad M, Kynast J, et al. Comparison of hospital mortality with intra-aortic balloon counterpulsation insertion before versus after primary percutaneous coronary intervention for cardiogenic shock complicating acute myocardial infarction. Am J Cardiol. 2010;105:967,971. [source] Age at onset in 3014 Sardinian bipolar and major depressive disorder patientsACTA PSYCHIATRICA SCANDINAVICA, Issue 6 2010L. Tondo Tondo L, Lepri B, Cruz N, Baldessarini RJ. Age at onset in 3014 Sardinian bipolar and major depressive disorder patients. Objective:, To test if onset age in major affective illnesses is younger in bipolar disorder (BPD) than unipolar-major depressive disorder (UP-MDD), and is a useful measure. Method:, We evaluated onset-age for DSM-IV-TR major illnesses in 3014 adults (18.5% BP-I, 12.5% BP-II, 69.0% UP-MDD; 64% women) at a mood-disorders center. Results:, Median and interquartile range (IQR) onset-age ranked: BP-I = 24 (19,32) < BP-II = 29 (20,40) < UP-MDD = 32 (23,47) years (P < 0.0001), and has remained stable since the 1970s. In BP-I patients, onset was latest for hypomania, and depression presented earlier than in BP-II or UP-MDD cases. Factors associated with younger onset included: i) being unmarried, ii) more education, iii) BPD-diagnosis, iv) family-history, v) being employed, vi) ever-suicidal, vii) substance-abuse and viii) ever-hospitalized. Onset-age distinguished BP-I from UP-MDD depressive onsets with weak sensitivity and specificity. Conclusion:, Onset age was younger among BPD than MDD patients, and very early onset may distinguish BPD vs. UP-MDD with depressive-onset. [source] Developmental assessment of preterm infants at 2 years: validity of parent reportsDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 1 2008Samantha Johnson PhD CPsychol Parental questionnaires are inexpensive alternatives to standardized testing for outcome measurement. The Parent Report of Children's Abilities has previously been revised (PARCA-R) and validated for use with very-preterm infants at 2 years of age. This study revalidated the PARCA-R for assessing cognition in a larger and more inclusive sample of preterm infants. One hundred and sixty-four children (82 males, 82 females) of <32 weeks' gestation (median 29wks, interquartile range [IQR] 28-30wks); and median birthweight 1200g (IQR 925-1463g) were evaluated using the Mental Development Index (MDI) of the Bayley Scales of Infant Development - 2nd edition (BSID-II) at 2 years' corrected age. Parents completed the PARCA-R questionnaire. Significant correlations between PARCA-R Parent Report Composite (PRC) scores and MDI scores (r=0.77, 95% confidence interval [CI] 0.69-0.82, p<0.01) demonstrated concurrent validity. A receiver operating characteristic-determined PRC cut-off of <44 had optimal discriminatory power (area under curve 0.92) for identifying MDI <70, with 85% sensitivity (95% CI 0.58-0.96), 87% specificity (95% CI 0.81-0.92), 98% negative predictive value (95% CI 0.95-1), and 37% positive predictive value (95% CI 0.22-0.54). The PARCA-R has good concurrent validity and diagnostic utility for identifying cognitive delay in very-preterm infants at 2 years of age. It is useful for outcome measurement, developmental screening, and facilitating parental involvement at folow-up. [source] Severe falciparum malaria and acquired childhood language disorderDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 1 2006Julie A Carter BSc (Hons) MSc PhD Language disorders have been reported after severe falciparum malaria but the deficits have not been described in detail. We assessed language outcome in three groups of children aged 6 to 9 years (n=487): those previously admitted to Kilifi District Hospital, Kenya, with cerebral malaria (CM; n=152; mean age 7y 4 mo [SD 1y 1mo]; 77 males, 75 females); or those with malaria and complicated seizures (M/S; n=156; mean age 7y 4mo [SD 1y 2mo]; 72 males, 84 females); and those unexposed to either condition (n=179; mean age 7y 6mo [SD 1y 1mo]; 93 males, 86 females). Median age at hospital admission was 28 months (interquartile range [IQR] 19 to 44 mo) among children with a history of CM and 23 months (IQR 12 to 35mo) among children with a history of M/S. A battery of eight assessments covering the major facets of speech and language was used to measure language performance. Cognitive performance, neurological/motor skills, behaviour, hearing, and vision were also measured. Eighteen (11.8%) of the CM group, 14 (9%) of the M/S group, and four (2.2%) of the unexposed group were found to have a language impairment. CM (odds ratio 3.68,95% confidence interval 1.09 to 12.4, p=0.04) was associated with significantly increased odds of an impairment-level score relative to the unexposed group. The results suggest that falciparum malaria is one of the most common causes of acquired language disorders in the tropics. [source] Elevated C-reactive protein in Native Canadian children: an ominous early complication of childhood obesityDIABETES OBESITY & METABOLISM, Issue 5 2006R. Retnakaran Aim:, Subclinical inflammation has been proposed as a pathophysiologic mechanism linking obesity with vascular and metabolic disease. Native North American populations are experiencing high prevalence rates of both (i) childhood obesity and (ii) adult cardiovascular disease (CVD) and type 2 diabetes. Thus, we sought to determine whether subclinical inflammation is an early complication of obesity in Native children. Methods:, Serum concentrations of the inflammatory biomarker C-reactive protein (CRP) were assessed in a population-based, cross-sectional study of the Sandy Lake Oji-Cree community of Northern Ontario, Canada, involving 228 children aged 10,19 years (mean age 14.8). Results:, Median CRP in this population was 0.5 mg/l (interquartile range 0.18,1.79 mg/l). CRP levels were higher than age-matched reference data from the Third National Health and Nutrition Examination Survey (NHANES III). Importantly, fully 15.8% of the children of this community had CRP concentrations between 3 and 10 mg/l, a range that identifies adults at high risk of CVD. Moreover, increasing CRP concentration in this paediatric population was associated with an enhanced CV risk profile, consisting of increased adiposity, higher insulin resistance, worsening lipid profile (higher total cholesterol, triglycerides, low-density lipoprotein cholesterol, apolipoprotein B and total cholesterol : high-density-lipoprotein cholesterol ratio), increased leptin and decreased adiponectin. On multivariate analysis, waist circumference and interleukin-6 (IL-6) emerged as independent determinants of CRP concentration. Conclusion:, Subclinical inflammation is an early complication of childhood obesity in Native children and may foreshadow an increased burden of CVD and type 2 diabetes in the future. [source] Prediction of cardiovascular and total mortality in Chinese type 2 diabetic patients by the WHO definition for the metabolic syndromeDIABETES OBESITY & METABOLISM, Issue 1 2006G. T.-C. Aim:, The aim of this study is to investigate the prevalence of metabolic syndrome (MES) in type 2 diabetic patients and the predictive values of the World Health Organization (WHO) and National Cholesterol Education Programme (NCEP) definitions and the individual components of the MES on total and cardiovascular mortality. Methods:, A prospective analysis of a consecutive cohort of 5202 Chinese type 2 diabetic patients recruited between July 1994 and April 2001. Results:, The prevalence of the MES was 49.2,58.1% depending on the use of various criteria. There were 189 deaths (men: 100 and women: 89) in these 5205 patients during a median (interquartile range) follow-up period of 2.1 (0.3,3.6 years). Of these, 164 (87%) were classified as cardiovascular deaths. Using the NCEP criterion, patients with MES had a death rate similar to those without (3.51 vs. 3.85%). By contrast, based on the WHO criteria, patients with MES had a higher mortality rate than those without (4.3 vs. 2.4%, p = 0.002). Compared to patients with neither NCEP- nor WHO-defined MES, only the group with MES defined by the WHO, but not NCEP, criterion had significantly higher mortality rate (2.6 vs. 6.8%, p < 0.001). Using Cox regression analysis, only age, duration of diabetes and smoking were identified as independent factors for cardiovascular or total death. Among the various components of MES, hypertension, low BMI and albuminuria were the key predictors for these adverse events. Conclusions:, In Chinese type 2 diabetic patients, the WHO criterion has a better discriminative power over the NCEP criterion for predicting death. Among the various components of the MES defined either by WHO or NCEP, hypertension, albuminuria and low BMI were the main predictors of cardiovascular and total mortality. [source] Assessment of different techniques for subcutaneous glucose monitoring in Type 1 diabetic patients during ,real-life' glucose excursionsDIABETIC MEDICINE, Issue 3 2010J. K. Mader Diabet. Med. 27, 332,338 (2010) Abstract Aims, To compare the accuracy of two marketed subcutaneous glucose monitoring devices (Guardian RT, GRT; GlucoDay S, GDS) and standard microdialysis (CMA60; MD) in Type 1 diabetic patients. Methods, Seven male Type diabetic patients were investigated over a period of 26 h simulating real-life meal glucose excursions. Catheters of the three systems were inserted into subcutaneous adipose tissue of the abdominal region. For MD, interstitial fluid was sampled at 30- to 60-min intervals for offline glucose determination. Reference samples were taken at 15- to 60-min intervals. All three systems were prospectively calibrated to reference. Median differences, median absolute relative differences (MARD), median absolute differences (MAD), Bland,Altman plot and Clark Error Grid were used to determine accuracy. Results, Bland,Altman analysis indicated a mean glucose difference (2 standard deviations) between reference and interstitial glucose of ,10.5 (41.8) % for GRT, 20.2 (55.9) % for GDS and 6.5 (35.2) % for MD, respectively. Overall MAD (interquartile range) was 1.07 (0.39; 2.04) mmol/l for GRT, 1.59 (0.54; 3.08) mmol/l for GDS and 0.76 (0.26; 1.58) mmol/l for MD. Overall MARD was 15.0 (5.6; 23.4) % (GRT), 19.7 (6.1; 37.6) % (GDS) and 8.7 (4.1; 18.3) % (MD), respectively. Total sensor failure occurred in two subjects using GRT and one subject using GDS. Conclusions, The three investigated technologies had comparable performance. Whereas GRT underestimated actual blood glucose, GDS and MD overestimated blood glucose. Considerable deviations during daily life meal glucose excursions from reference glucose were observed for all three investigated technologies. Present technologies may require further improvement until individual data can lead to direct and automated generation of therapeutic advice in diabetes management. [source] Measurement delay associated with the Guardian® RT continuous glucose monitoring systemDIABETIC MEDICINE, Issue 1 2010C. Wei Diabet. Med. Abstract Aims, Using compartment modelling, we assessed the time delay between blood glucose and sensor glucose measured by the Guardian® RT continuous glucose monitoring system in young subjects with Type 1 diabetes (T1D). Methods, Twelve children and adolescents with T1D treated by continuous subcutaneous insulin infusion (male/female 7/5; age 13.1 ± 4.2 years; body mass index 21.9 ± 4.3 kg/m2; mean ± sd) were studied over 19 h in a Clinical Research Facility. Guardian® RT was calibrated every 6 h and sensor glucose measured every 5 min. Reference blood glucose was measured every 15 min using a YSI 2300 STAT Plus Analyser. A population compartment model of sensor glucose,blood glucose kinetics was adopted to estimate the time delay, the calibration scale and the calibration shift. Results, The population median of the time delay was 15.8 (interquartile range 15.2, 16.5) min, which was corroborated by correlation analysis between blood glucose and 15-min delayed sensor glucose. The delay has a relatively low intersubject variability, with 95% of individuals predicted to have delays between 10.4 and 24.3 min. Population medians (interquartile range) for the scale and shift are 0.800 (0.777, 0.823) (unitless) and 1.66 (1.47, 1.84) mmol/l, respectively. Conclusions, In young subjects with T1D, the total time delay associated with the Guardian® RT system was approximately 15 min. This is twice that expected on physiological grounds, suggesting a 5- to 10-min delay because of data processing. Delays above 25 min are rarely to be observed. [source] J-shaped relationship between waist circumference and subsequent risk for Type 2 diabetes: an 8-year follow-up of relatively lean Japanese individualsDIABETIC MEDICINE, Issue 8 2009M. Sakurai Abstract Aims, This study investigated the relationship between waist circumference and the subsequent incidence of Type 2 diabetes and the association with insulin resistance and pancreatic B-cell function in relatively lean Japanese individuals. Methods, The study participants were 3992 employees (2533 men and 1459 women, aged 35,55 years) of a metal-products factory in Japan. The incidence of diabetes was determined in annual medical examinations during an 8-year follow-up. We calculated age- and sex-adjusted hazard ratios (HRs) according to the sex-specific quintile of waist circumference at baseline. Differences in baseline insulin resistance [homeostatis model assessment (HOMA)-IR] and pancreatic B-cell function (HOMA-B) were compared between participants who developed diabetes and those who did not. Results, During the follow-up, 218 participants developed diabetes. Age- and sex-adjusted HRs across the quintiles of waist circumference were 1.78, 1.00 (reference), 1.59, 3.11 and 3.30, respectively (P for trend, < 0.0001). The HR for the lowest quintile was significantly higher than that for the second quintile. Among participants with waist circumference of the lowest quintile, HOMA-B was lower in those who developed diabetes than in those who did not [33.1 (24.1,45.0) vs. 54.3 (37.9,74.6) median (interquartile range), P < 0.0001], but HOMA-IR did not differ between these groups. Conclusions, There was a J-shaped relationship between waist circumference and subsequent risk for Type 2 diabetes in relatively lean Japanese individuals; lower pancreatic B-cell function may also increase the risk of diabetes in very lean Japanese people. [source] Effect of ABCA1 variant on atherogenic dyslipidaemia in patients with Type 2 diabetes treated with rosiglitazoneDIABETIC MEDICINE, Issue 6 2009S. E. Park Abstract Aims, To investigate the effect of two common ATP-binding cassette transporter 1 (ABCA1) polymorphisms (rs4149263 and rs2020927) on atherogenic dyslipidaemia in Korean Type 2 diabetic patients who were treated with rosiglitazone. Patients and methods, Two hundred and fifty-six patients with Type 2 diabetes who had never previously received peroxisome proliferator-activated receptor gamma (PPAR-,) agonists or lipid-lowering treatment were treated with 4 mg of rosiglitazone daily for 12 weeks without any adjustment to their glucose-lowering regimen. The primary outcome was the change in atherogenic index of plasma (AIP), calculated as log [triglyceride (mmol/l)/high-density lipoprotein cholesterol (mmol/l)], before and after rosiglitazone treatment. The effect of rosiglitazone on the change in AIP was compared across the ABCA1 single nucleotide polymorphisms (SNPs) rs41429263 and rs2020927. Results, Before adjustment, the change in AIP at 12 weeks was significantly different across the rs4149263 genotypes [median (interquartile range): ,0.05 (,0.21, 0.09) for TT; 0.02 (,0.09, 0.17) for TC; and 0.11 (0.03, 0.25) for CC; P = 0.003], but not across the rs2020927 [,0.04 (,0.18, 0.10) for TT; 0.03 (,0.17, 0.15) for TC; and ,0.03 (,0.13, 0.10) for CC; P = 0.401]. After controlling for age, gender and duration of diabetes, the presence of the C-allele was significantly associated with an increase in AIP by 0.13 [95% confidence interval (CI), 0.04,0.21; P = 0.003]. This association did not change significantly when body mass index and pretreatment metabolic parameters were additionally controlled for (the change in AIP: 0.14; 95% CI, 0.04,0.24; P = 0.007). Conclusions, The ABCA1 SNP rs4149263 may be associated with the change in atherogenic lipid profile in Type 2 diabetes treated with rosiglitazone. [source] Establishing pragmatic estimated GFR thresholds to guide metformin prescribingDIABETIC MEDICINE, Issue 10 2007J. S. Shaw Abstract Aims, Renal impairment is a contraindication to metformin treatment because of the perceived increased risk of lactic acidosis. Current guidelines define renal impairment according to the serum creatinine of the individual, but this measure is being supplanted by the use of estimated glomerular filtration rate (eGFR) as it gives a closer estimate to true GFR. This study aimed to establish pragmatic eGFR limits for use in patients being considered for metformin treatment. Methods, Estimated GFR measurements corresponding to currently used metformin creatinine limits of 130 and 150 µmol/l were derived and then applied to 12 482 patients with diabetes in Hull and East Yorkshire. Results, Few patients with a serum creatinine of 130 or 150 µmol/l have an eGFR of < 30 ml/min/1.73 m2[chronic kidney disease (CKD) stage 4 or greater], while most are between 30 and 59 ml/min/1.73 m2 (CKD stage 3). When applied to the 12 482 patients (median age 67 years, interquartile range 56,75), males predominated when using creatinine cut-offs (13.6% of males and 8.3% of females had creatinine > 130 µmol/l; 8.2% males and 5.2% females > 150 µmol/l), but not using eGFR CKD thresholds (3.3% males and 4.7% females < 30 ml/min/1.73 m2; 20.8% males and 28.1% females eGFR 30,59 ml/min/1.73 m2). Similar proportions of patients as currently would have metformin withheld if using eGFR cut-offs between 30 and 49 ml/min/1.73 m2. Conclusions, We have proposed pragmatic eGFR limits to guide metformin prescribing in patients with renal impairment. CKD stage 4 or greater should be an absolute contraindication to metformin, while CKD stage 3 should alert clinicians to consider other risk factors before initiating or continuing treatment. [source] Nocturnal hypoglycaemia in Type 1 diabetic patients, assessed with continuous glucose monitoring: frequency, duration and associationsDIABETIC MEDICINE, Issue 5 2007I. M. E. Wentholt Abstract Aims, We quantified the occurrence and duration of nocturnal hypoglycaemia in individuals with Type 1 diabetes treated with continuous subcutaneous insulin infusion (CSII) or multiple-injection therapy (MIT) using a continuous subcutaneous glucose sensor. Methods, A microdialysis sensor was worn at home by 24 patients on CSII (mean HbA1c 7.8 ± 0.9%) and 33 patients on MIT (HbA1c 8.7 ± 1.3%) for 48 h. Occurrence and duration of nocturnal hypoglycaemia were assessed and using multivariate regression analysis, the association between HbA1c, diabetes duration, treatment type (CSII vs. MIT), fasting and bedtime blood glucose values, total daily insulin dose and mean nocturnal glucose concentrations, and hypoglycaemia occurrence and duration was investigated. Results, Nocturnal hypoglycaemia , 3.9 mmol/l occurred in 33.3% of both the CSII- (8/24) and MIT-treated patients (11/33). Mean (± sd; median, interquartile range) duration of hypoglycaemia , 3.9 mmol/l was 78 (± 76; 57, 23,120) min per night for the CSII- and 98 (± 80; 81, 32,158) min per night for the MIT-treated group. Multivariate regression analysis showed that bedtime glucose value had the strongest association with the occurrence (P = 0.026) and duration (P = 0.032) of nocturnal hypoglycaemia. Conclusions, Microdialysis continuous glucose monitoring has enabled more precise quantification of nocturnal hypoglycaemia occurrence and duration in Type 1 diabetic patients. Occurrence and duration of nocturnal hypoglycaemia were mainly associated with bedtime glucose value. [source] Familial factors in diabetic nephropathy: an offspring studyDIABETIC MEDICINE, Issue 3 2006E. Agius Abstract Aims Familial clustering of diabetic nephropathy in patients with Type 2 diabetes suggests that inherited factors predispose to diabetic nephropathy, but the nature of these factors is uncertain. The aim of the study was to compare the prevalence of known risk factors for nephropathy in non-diabetic offspring of Type 2 diabetic patients with and without nephropathy and in control subjects. Methods Three groups of patients were recruited with 40 or 41 subjects in each group. These were subjects having one Type 2 diabetic parent with nephropathy (DN); subjects having one parent with Type 2 diabetes without nephropathy (DnoN), and non-diabetic unrelated control subjects with no personal or parental history of diabetes (Control subjects). Results The median (interquartile range) albumin/creatinine ratio (ACR) was 1.40 (0.96,2.90) mg/mmol in DN; 0.94 (0.50,1.46) mg/mmol in DnoN and 1.22 (0.66,1.83) mg/mmol in Controls (anova: P = 0.03). ACR was higher in group DN than in DnoN (P < 0.006) and in Control subjects (P < 0.03), but there was no difference between DnoN and Control subjects. Twenty-four-hour ambulatory blood pressure monitoring showed mean daytime systolic blood pressure to be significantly higher in group DN than in DnoN (P < 0.02) or Control subjects (P < 0.01) (anova: P = 0.004). Fasting insulin, HOMA-IR, interleukin-6 (IL-6) and C-reactive protein (CRP) were similar in the three groups. Conclusion Our data provide further evidence that genetic factors are important in determining urinary albumin excretion and renal disease associated with Type 2 diabetes and suggest that genes that affect systemic arterial blood pressure but not those relating to insulin resistance or inflammation are likely to be implicated. [source] Sorbitol and myo -inositol levels and morphology of sural nerve in relation to peripheral nerve function and clinical neuropathy in men with diabetic, impaired, and normal glucose toleranceDIABETIC MEDICINE, Issue 4 2000G. Sundkvist Abstracts Aims Sorbitol and myo -inositol levels and morphology of sural nerve were compared with nerve function and clinical neuropathy in men with diabetic, impaired (IGT), and normal glucose tolerance. Methods After neurography of sural nerve and determinations of sensory thresholds for vibration, warm and cold on the foot, whole nerve sural nerve biopsy was performed in 10 men with Type 1 diabetes mellitus, 10 with IGT, and 10 with normal glucose tolerance. Polyol levels were assessed by gas,liquid chromatography/mass spectrometry. Results Sural nerve amplitudes were significantly lower and sorbitol levels significantly higher in diabetic patients (median (interquartile range)) (3.7 (3.5) ,V and 643 (412) pmol/mg protein, respectively) both compared with IGT (11.3 (10.6) ,V; P = 0.04 and 286 (83) pmol/mg protein; P = 0.0032, respectively) and normally glucose tolerant (10.0 (11.6); P = 0.0142 and 296 (250) pmol/mg protein; P = 0.0191, respectively) subjects. There were no differences in nerve morphology between the three groups. Nerve myo -inositol levels correlated, however, positively with cluster density (rs = 0.56; P = 0.0054). In diabetic and IGT subjects, sural nerve amplitudes (2.6 (3.8) vs. 12.1 (10.6) ,V; P = 0.0246) and myelinated nerve fibre density (MNFD; 4076 (1091) vs. 5219 (668) nerve fibres/mm2; P = 0.0021) were significantly lower in nine subjects with clinical neuropathy than in 10 without. Conclusions Nerve degeneration (i.e. MNFD) correlated with clinical neuropathy but not with glucose tolerance status whereas nerve myo -inositol levels positively correlated with signs of nerve regeneration (i.e. increased cluster density). [source] The Impact of a Concurrent Trauma Alert Evaluation on Time to Head Computed Tomography in Patients with Suspected StrokeACADEMIC EMERGENCY MEDICINE, Issue 3 2006Esther H. Chen MD Background: Emergency department (ED) overcrowding threatens quality of care by delaying the time to diagnosis and treatment of patients with time-sensitive diseases, such as acute stroke. Objective: The authors hypothesized that the presence of a trauma alert evaluation would impede the time to head computed tomography (hCT) in patients with stroke-like symptoms. Methods: This was a secondary analysis of prospectively collected data on patients with potential stroke who received an hCT in an urban trauma center ED from January 1, 2004, to November 30, 2004. Structured data collection included historical and examination items, National Institutes of Health (NIH) stroke scale score, laboratory and radiographic results, and final diagnosis. Admitted patients were followed in hospital. Patients who presented within one hour following a trauma evaluation were compared with patients who presented without concurrent trauma for triage time until completion of hCT. Chi-square, t-tests, and 95% confidence intervals (95% CIs) were used for comparisons. Results: The 171 patients enrolled had a mean (± standard deviation) age of 60.7 (± 7) years; 60% were female; and 58% were African American. Of these, 72 patients had a significant cerebrovascular event (38 [22%] ischemic stroke, 25 [15%] transient ischemic attack, seven [4%] intracranial hemorrhage, one [0.6%] subarachnoid hemorrhage, and one [0.6%] subdural hematoma). The remaining diagnoses included 4.6% migraine, 2.3% seizure, 2.9% syncope, 2.3% Bell's palsy, and 2.9% vertigo. There was no significant difference in time to hCT in patients who presented during a trauma activation and those who did not (99 minutes [interquartile range (IQR) = 24,156] vs. 101 minutes [IQR = 43,151.5]; p = 0.537). In subgroup analysis of patients with a significant cerebrovascular event, times to hCT were also similar (24 minutes [IQR = 12,99] vs. 61 minutes [IQR = 15,126]; p = 0.26). Conclusions: In the authors' institution, the presence of concurrent trauma evaluation does not delay CT imaging of patients with potential stroke. [source] Validation of the Mayo Dysphagia QuestionnaireDISEASES OF THE ESOPHAGUS, Issue 3 2007A. B. M. Grudell SUMMARY., While multiple instruments characterize upper gastrointestinal symptoms, a validated instrument devoted to the measurement of a spectrum of esophageal dysphagia attributes is not available. Therefore, we constructed and validated the Mayo Dysphagia Questionnaire (MDQ). The 27 items of the MDQ underwent content validity, feasibility, concurrent validity, reproducibility, internal consistency, and construct validity testing. To assess content validity, five esophageal subspecialty gastroenterologists reviewed the items to ensure inclusion of pertinent domains. Feasibility testing was done with eight outpatients who refined problematic items. To assess concurrent validity, 70 patient responses on the MDQ were compared to responses gathered in a structured patient-physician interview. A separate group of 70 outpatients completed the MDQ twice to assess the reproducibility of each item. A total of 148 patients participated in the validation process (78 [53%] men; mean age 62). On average, the MDQ took 6 minutes to complete. A single item (odynophagia) tested poorly with a kappa value of < 0.4. Otherwise, the majority of concurrent validity kappa values were in the good to excellent range with a mean of 0.63 (95% CI 0.22,0.89). The majority of reproducibility kappa values were also in the good to excellent range with a median kappa value of 0.76 (interquartile range: 0.67,0.81). Cronbach's alpha values were excellent in the range of 0.86,0.88. Spearman rank correlation coefficients to assess construct validity were also excellent in the range of 0.87,0.98. Thus, the MDQ is a concise instrument that demonstrates overall excellent concurrent validity, reproducibility, internal consistency, and construct validity for the features of esophageal dysphagia. [source] Alcohol use and non-adherence to antiretroviral therapy in HIV-infected patients in West AfricaADDICTION, Issue 8 2010Antoine Jaquet ABSTRACT Aim To investigate the association between alcohol use and adherence to highly active antiretroviral treatment (HAART) among human immunodeficiency virus (HIV)-infected patients in subSaharan Africa. Design and setting Cross-sectional survey conducted in eight adult HIV treatment centres from Benin, Côte d'Ivoire and Mali. Participants and measurements During a 4-week period, health workers administered the Alcohol Use Disorders Identification Test to HAART-treated patients and assessed treatment adherence using the AIDS Clinical Trials Group follow-up questionnaire. Findings A total of 2920 patients were enrolled with a median age of 38 years [interquartile range (IQR) 32,45 years] and a median duration on HAART of 3 years (IQR 1,4 years). Overall, 91.8% of patients were identified as adherent to HAART. Non-adherence was associated with current drinking [odds ratio (OR) 1.4; 95% confidence interval (CI) 1.1,2.0], hazardous drinking (OR 4.7; 95% CI 2.6,8.6) and was associated inversely with a history of counselling on adherence (OR 0.7; 95% CI 0.5,0.9). Conclusions Alcohol consumption and hazardous drinking is associated with non-adherence to HAART among HIV-infected patients from West Africa. Adult HIV care programmes should integrate programmes to reduce hazardous and harmful drinking. [source] Emergency Department Patient Volume and Troponin Laboratory Turnaround TimeACADEMIC EMERGENCY MEDICINE, Issue 5 2010Ula Hwang MD Abstract Objectives:, Increases in emergency department (ED) visits may place a substantial burden on both the ED and hospital-based laboratories. Studies have identified laboratory turnaround time (TAT) as a barrier to patient process times and lengths of stay. Prolonged laboratory study results may also result in delayed recognition of critically ill patients and initiation of appropriate therapies. The objective of this study was to determine how ED patient volume itself is associated with laboratory TAT. Methods:, This was a retrospective cohort review of patients at five academic, tertiary care EDs in the United States. Data were collected on all adult patients seen in each ED with troponin laboratory testing during the months of January, April, July, and October 2007. Primary predictor variables were two ED patient volume measures at the time the troponin test was ordered: 1) number of all patients in the ED/number of beds (occupancy) and 2) number of admitted patients waiting for beds/beds (boarder occupancy). The outcome variable was troponin turnaround time (TTAT). Adjusted covariates included patient characteristics, triage severity, season (month of the laboratory test), and site. Multivariable adjusted quantile regression was carried out to assess the association of ED volume measures with TTAT. Results:, At total of 9,492 troponin tests were reviewed. Median TTAT for this cohort was 107 minutes (interquartile range [IQR] = 73,148 minutes). Median occupancy for this cohort was 1.05 patients (IQR = 0.78,1.38 patients) and median boarder occupancy was 0.21 (IQR = 0.11,0.32). Adjusted quantile regression demonstrated a significant association between increased ED patient volume and longer times to TTAT. For every 100% increase in census, or number of boarders over the number of ED beds, respectively, there was a 12 (95% confidence interval [CI] = 9 to 14) or 33 (95% CI = 24 to 42)-minute increase in TTAT. Conclusions:, Increased ED patient volume is associated with longer hospital laboratory processing times. Prolonged laboratory TAT may delay recognition of conditions in the acutely ill, potentially affecting clinician decision-making and the initiation of timely treatment. Use of laboratory TAT as a patient throughput measure and the study of factors associated with its prolonging should be further investigated. ACADEMIC EMERGENCY MEDICINE 2010; 17:501,507 © 2010 by the Society for Academic Emergency Medicine [source] Determinants of successful chronic hepatitis C case finding among patients receiving opioid maintenance treatment in a primary care settingADDICTION, Issue 12 2009Oliver Senn ABSTRACT Aims Injection drug users are at high risk for chronic hepatitis C virus infection (CHC). Opioid maintenance treatment (OMT) offers a unique opportunity to screen for CHC. This study proposed the hypothesis that a general practitioner (GP) with special interest in addiction medicine can achieve CHC screening rates comparable to specialized centres and aimed to investigate determinants for a successful CHC case finding in a primary care setting. Design and participants Retrospective medical record analysis of 387 patients who received opioid maintenance therapy between 1 January 2002 and 31 May 2008 in a general practice in Zurich, Switzerland. Measurements Successful CHC assessment was defined as performance of hepatitis C virus (HCV) serology with consecutive polymerase chain reaction-based RNA and genotype recordings. The association between screening success and patient characteristics was assessed using multiple logistic regression. Findings Median (interquartile range) age and duration of OMT of the 387 (268 males) patients was 38.5 (33.6,44.5) years and 34 (11.3,68.0) months, respectively. Fourteen patients (3.6%) denied HCV testing and informed consent about screening was missing in 13 patients (3.4%). In 327 of 360 patients (90.8%) with informed consent a successful CHC assessment has been performed. Screening for HCV antibodies was positive in 136 cases (41.6%) and in 86 of them (63.2%) a CHC was present. The duration of OMT was an independent determinant of a successful CHC assessment. Conclusions In addicted patients a high CHC assessment rate in a primary care setting in Switzerland is feasible and opioid substitution provides an optimal framework. [source] The effect of nightshift on emergency registrars' clinical skillsEMERGENCY MEDICINE AUSTRALASIA, Issue 3 2010Leonie Marcus Abstract Objective: The effect of nightshift on ED staff performance is of clinical and risk-management significance. Previous studies have demonstrated deterioration in psychomotor skills but the present study specifically assessed the impact of nightshift on clinical performance. Methods: The ED registrars in a tertiary hospital were enrolled in a prospective observational study and served as their own controls. During nightshift, subjects were presented simulated scenarios and tested with eight clinical questions developed to Fellowship examination standard. Matched scenarios and questions for the same subjects during dayshift served as controls. Two investigators, blinded to subject identity and the setting in which questions were attempted, independently collated answers. Results: Of 22 eligible subjects, all were recruited; four were excluded owing to incomplete data. A correlation of 0.99 was observed between the independent scoring investigators. Of a possible score of 17, the median result for nightshift was 9.5 (interquartile range: 8,11); corresponding value for dayshift was 12 (interquartile range: 10,13); P= 0.047. Conclusion: Nightshift effect on clinical performance is anecdotally well known. The present study quantifies such effects, specifically for the ED setting, and paves the way for focused research. The implications for clinical governance strategies are significant, as the fraternity embraces the mandate to maintain quality emergency care 24 h per day. [source] Does the standard intravenous solution of fentanyl (50 µg/mL) administered intranasally have analgesic efficacy?EMERGENCY MEDICINE AUSTRALASIA, Issue 1 2010Dianne Crellin Abstract Background: Intranasal (IN) fentanyl provides rapid and powerful non-parenteral analgesia in the ED. A concentrated solution of fentanyl (300 µg/mL) has been used in prior trials, yet many ED use the standard solution at a concentration of 50 µg/mL, which is widely available and of low cost. We set out to determine if this lower concentration of fentanyl is also efficacious. Methods: Prospective audit in children aged 5,18 years presenting with upper limb injuries. Patients received IN fentanyl (50 µg/mL) at 1.5 µg/kg. Patient assessed pain scores were collected 5, 10, 20, 30 and 60 min following IN fentanyl administration using a visual analogue scale or Bieri Faces , Revised scale. Parental scores were used if patients were unable to provide a score. Results: Of the 59 eligible patients, 36 were enrolled; median age was 6.8 years (range 5,15 years), and 89% (32/36) ultimately required fracture reduction. Median first dose of IN fentanyl was 1.4 µg/kg. Median pain scores dropped from 7 (interquartile range 5,10) pre-fentanyl to 5 (interquartile range 4,8) at 5 min and 2 (interquartile range 1,4) at 30 and 60 min. A total of 21 (58%) children did not require further analgesia in the ED. There were no adverse events. Conclusions: Standard i.v. concentration IN fentanyl (50 µg/mL) appears to have analgesic efficacy in children with upper limb injuries. [source] Intranasal fentanyl in 1,3-year-olds: A prospective study of the effectiveness of intranasal fentanyl as acute analgesiaEMERGENCY MEDICINE AUSTRALASIA, Issue 5 2009Joanne Cole Abstract The primary objective of the present study was to determine the effectiveness of intranasal fentanyl analgesia in children aged 1,3 years with acute moderate to severe pain presenting to the ED. We also aimed to gather information on the safety and acceptability of intranasal fentanyl in this age group. Two paediatric ED enrolled children aged 1,3 years, with acute moderate or severe pain. Intranasal fentanyl was administered (1.5 µg/kg) via a mucosal atomiser device using a 50 µg/mL solution of fentanyl. Physiological parameters (heart rate, respiratory rate, oxygen saturations and level of consciousness) were measured at regular intervals. Objective pain assessment was completed using the Faces, Legs, Arms, Cry, Consolability (FLACC) score. Forty-six children presenting with acute moderate to severe pain were included. The median FLACC score before intranasal fentanyl administration was 8 (interquartile range [IQR] 5,10), decreasing to 2 (IQR 0,4) 10 min post fentanyl (P < 0.0001) and 0 (IQR 0,2) 30 min post fentanyl (P < 0.0001). A clinically significant decrease in FLACC scores was seen in 93% of children 10 min post fentanyl administration and 98% of children 30 min post fentanyl. Intranasal fentanyl delivery using a mucosal atomiser was well tolerated by all children. There were no adverse drug reactions or adverse events detected. Intranasal fentanyl is an effective, safe and well-tolerated mode of analgesia for children aged 1,3 years with moderate to severe pain. [source] Evaluation of emergency medicine trainees' ability to use transport equipmentEMERGENCY MEDICINE AUSTRALASIA, Issue 3 2009Manoj Samuel Abstract Objective: To assess the skills of advanced emergency medicine trainees in the use of commonly used transport equipment and to determine what teaching has been undertaken and what level of confidence trainees have in their ability to use the equipment tested. Methods: This is a prospective multicentre observational study examining equipment use. Three pieces of equipment were examined: the infusion pump, defibrillator-monitor and transport ventilator. A questionnaire and a series of practical tasks were used. Advanced trainees from Victorian ED were enrolled as participants. Outcomes included proportion of participants able to perform all tasks successfully, subjective registrar confidence with use of equipment and departmental training practices. Eleven ED were represented, covering metropolitan tertiary, metropolitan peripheral and regional hospitals. Results: There were 47 participants enrolled in the study. The range of advanced training years of participants was 1,5+. Of the 47 participants, 39 (83%; 95% CI 72.2,93.7%) had been involved as medical escorts. Eighteen participants (38.3%; 95% CI 24.4,52.2%) described some form of teaching for equipment use. The median level of confidence of participants (on a 5-point scale) was 4 (25,75% interquartile range 3,4), which correlates with a moderate degree of confidence. Of 47 participants, 7 (14.9%; 95% CI 4.7,25.1%) rated themselves as not confident or somewhat under-confident (i.e. 1 or 2 on the scale). Of 47, 12 passed overall (25.5%; 95% CI 13.1,38%) and 8 completely failed (17.0%; 95% CI 6.3,27.8%) the skill testing. Conclusion: When tested in isolation, there appears to be deficits in the equipment skills of advanced ED trainees who are expected to be proficient in transport medicine. [source] Epidemiology of unarmed threats in the emergency departmentEMERGENCY MEDICINE AUSTRALASIA, Issue 4 2005Jonathan C Knott Abstract Objective:, To evaluate the precipitants, subject characteristics, nature and outcomes of unarmed threats in the ED. Methods:, A 12 month prospective survey of security codes precipitated by an unarmed threat (Code Grey). Results:, Data were collected on 151 subjects. The Code Grey rate was 3.2/1000 ED presentations. They were most frequent on Saturday and in the late evening/early morning. There were verbal or physical threats of violence made to staff on 104 occasions (69%, 95% confidence interval [CI] 61,76) and a perceived threat of patient self-harm on 114 occasions (76%, 95% CI 68,82). Median time to be seen by a doctor was 8 min (interquartile range [IQR]: 2,21 min) and median time from presentation to Code was 59 min (IQR: 5,222 min). Sixteen subjects (11%, 95% CI 6,17) had a history of violence, 45 (30%, 95% CI 23,38) were affected by alcohol, 25 (17%, 95% CI 11,24) had used illicit drugs and 79 (52%, 95% CI 44,60) had a significant mental illness contributing to the Code Grey. Seventy-one patients (47%, 95% CI 39,55) required psychiatric admission, 49 (79%, 95% CI 66,88) involuntarily. Conclusion:, Acutely agitated subjects pose a threat to themselves and the staff caring for them. The reason for the agitation is multifactorial and the majority arrive in a behaviourally disturbed state requiring early intervention. The times most likely to result in a Code Grey coincide with least available resources: ED and hospital risk management policies must account for this. A coherent approach by ED to this population is required to optimize patient and staff outcomes. [source] Adolescent emergency department presentations with alcohol- or other drug-related problems in Perth, Western AustraliaADDICTION, Issue 7 2001Gary K. Hulse Aims. To identify the morbidity, type of substance used and the pattern of presentation by adolescents with problems related to alcohol or other drug (AOD) use. Design. A 4-week retrospective review of hospital records. Setting. Four metropolitan hospitals in Perth, Australia. Participants. There were 1064 presentations by people aged 12-19 years of which 160 (15%) were related to AOD use. The median age of the AOD cases was 17 (interquartile range 16-19) of whom 97 (61%) were male and 19 (12%) were Indigenous Australians. Findings. Alcohol was the most frequent precursor to presentation (66, 41%) followed by heroin (24, 15%) and prescription/over-the-counter drugs (24, 15%). Injury was the most common diagnosis at presentation (50, 31%), followed by overdose/drug use (47, 29%). A diagnosis of injury was significantly more likely following the use of alcohol than other categories of substances (,2 = 42.07, df = 3, p < 0.001). Deliberate self-harm (DSH) occurred in more female than male cases (,2 = 7.4, df = 1, p < 0.01). Presentations were more frequent over the weekend (102, 64%) than on weekdays, and the length of stay was significantly shorter for weekend cases (Mann-Whitney U 2132, p < 0.05). Conclusions. Given the small window of opportunity to provide AOD treatment to youth following hospital presentation, a number of suggestions are made. From a harm-minimization perspective the focus of interventions should be on alcohol use by male youth and DSH associated with prescription/over-the-counter drug use by female adolescents. In addition, Indigenous youth are over-represented in hospital presentations, but there is currently a lack of evaluated interventions designed for them. [source] Measurement of the soluble angiopoietin receptor tie-2 in patients with coronary artery disease: development and application of an immunoassayEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 7 2003N. A. Y. Chung Abstract Background The angiopoietin family has emerged as a group of crucial growth factors to normal angiogenesis. They are essential to the development of the mature vessel wall and interact with the endothelium via endothelial cell-specific tyrosine kinase receptors, tie-1 and tie-2. The role of the tie-2 receptor has been extensively examined in neovascularization associated with malignancy, but little is known about the role it may play in atherosclerosis, a condition whose pathophysiology also involves angiogenesis. Soluble tie-2 has been detected in the plasma of healthy controls, but this has yet to be applied to patients in the clinical setting. Materials and methods We developed an ELISA to detect plasma tie-2 levels and applied these to a clinical setting. The intra- and interassay coefficients of variation for the assay were 4·7% and 9·6%, respectively. We then measured levels of tie-2, vascular endothelial growth factor (VEGF), another factor associated with angiogenesis, and the soluble VEGF receptor Flt-1 (sFlt-1) in 75 patients with coronary artery disease [25 with acute myocardial infarction (AMI), 25 with acute coronary syndromes (ACS) and 25 with stable angina] and 25 healthy controls. Results Median [IQR, interquartile range] levels of tie-2 were significantly higher in the coronary artery disease patients (AMI 12 [10,17] ng mL,1, ACS 10 [9,14] ng mL,1, stable angina 9 [3,11] ng mL,1) when compared with the controls (7·5 [7,9] ng mL,1P = 0·004). As expected, levels of VEGF and sFlt were significantly different from those in the healthy controls (P = 0·011 and P < 0·001, respectively). Significant correlations were found between levels of tie-2 and VEGF (Spearman r = 0·59, P < 0·001), tie-2 and sFlt-1 (r = 0·45, P < 0·001) and VEGF and sFlt-1 (r = 0·56, P < 0·001) in the whole study group. Conclusion We suggest that tie-2 may be potentially used as a marker of angiogenesis in atherosclerosis and may help elucidate the role of the angiopoietin/tie-2 system in atherogenesis. [source] Early treatment after a symptomatic event is not associated with an increased risk of stroke in patients undergoing carotid stentingEUROPEAN JOURNAL OF NEUROLOGY, Issue 1 2008K. Gröschel A recently symptomatic carotid artery stenosis carries a high risk of subsequent ischaemic events and thus requires rapid treatment. We investigated the influence of the time delay between the last symptomatic event of a carotid stenosis and subsequent carotid artery stenting (CAS) with respect to the combined 30-day outcome of stroke and death. In a group of 320 patients undergoing CAS the median delay before the intervention was 19 days (interquartile range 10,36) and the combined 30-day complication rate was 8.4%. Time delay was not significantly associated with peri-procedural complications, regardless of whether this variable was dichotomized (<14 days and ,14 days), separated into interquartile ranges or analysed as a continuous variable. Our results indicate that early CAS is not associated with an increased complication rate in patients with a recently symptomatic carotid stenosis. Thus, if CAS has been selected as the treatment modality for a patient, it should be performed as soon as possible to maximize the benefit of the intervention in reducing the risk of stroke. [source] Variation in Institutional Review Board Responses to a Standard Protocol for a Multicenter Clinical TrialACADEMIC EMERGENCY MEDICINE, Issue 6 2001Thomas O. Stair MD Abstract. Multicenter clinical trials require approval by multiple local institutional review boards (IRBs). The Multicenter Airway Research Collaboration mailed a clinical trial protocol to its U.S. investigators and 44 IRBs ultimately reviewed it. Objective: To describe IRB responses to one standard protocol and thereby gain insight into the advantages and disadvantages of local IRB review. Methods: Two surveys were mailed to participants, with telephone follow-up of nonrespondents. Survey 1 was mailed to 82 investigators across North America. Survey 2 was mailed to investigators from 44 medical centers in 17 U.S. states. Survey 1 asked about each investigator's local IRB (e.g., frequency of meetings, membership), whereas survey 2 asked about IRB queries and concerns related to the submitted clinical trial. Results: Both surveys had 100% response rate. Investigators submitted applications a median of 58 days (interquartile range [IQR], 40-83) after receipt of the protocol, and IRB approval took an additional 38 days (IQR, 26-62). Although eight applications were approved with little or no changes, IRBs requested an average of 3.5 changes per site. Changes involved study logistics and supervision for 45%, the research process for 43%, and the consent form for 91%. Despite these numerous requests, all eventually approved the basic protocol, including inclusion criteria, intervention, and data collection. Conclusions: The IRBs showed extreme variability in their initial responses to a standard protocol, but ultimately all gave approval. Almost all IRBs changed the consent form. A national, multicenter IRB process might streamline ethical review and warrants further consideration. [source] Distribution of benthic diatoms in U.S. rivers in relation to conductivity and ionic compositionFRESHWATER BIOLOGY, Issue 8 2003Marina Potapova Summary 1We quantified the relationships between diatom relative abundance and water conductivity and ionic composition, using a dataset of 3239 benthic diatom samples collected from 1109 river sites throughout the U.S.A. [U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program dataset]. This dataset provided a unique opportunity to explore the autecology of freshwater diatoms over a broad range of environmental conditions. 2Conductivity ranged from 10 to 14 500 ,S cm,1, but most of the rivers had moderate conductivity (interquartile range 180,618 ,S cm,1). Calcium and bicarbonate were the dominant ions. Ionic composition, however, varied greatly because of the influence of natural and anthropogenic factors. 3Canonical correspondence analysis (CCA) and Monte Carlo permutation tests showed that conductivity and abundances of major ions (HCO + CO, Cl,, SO, Ca2+, Mg2+, Na+, K+) all explained a statistically significant amount of the variation in assemblage composition of benthic diatoms. Concentrations of HCO + CO and Ca2+ were the most significant sources of environmental variance. 4The CCA showed that the gradient of ionic composition explaining most variation in diatom assemblage structure ranged from waters dominated by Ca2+ and HCO + CO to waters with higher proportions of Na+, K+, and Cl,. The CCA also revealed that the distributions of some diatoms correlated strongly with proportions of individual cations and anions, and with the ratio of monovalent to divalent cations. 5We present species indicator values (optima) for conductivity, major ions and proportions of those ions. We also identify diatom taxa characteristic of specific major-ion chemistries. These species optima may be useful in future interpretations of diatom ecology and as indicator values in water-quality assessment. [source] | |||||||||||||