Weaker Correlation (weaker + correlation)

Distribution by Scientific Domains


Selected Abstracts


US state alcohol sales compared to survey data, 1993,2006

ADDICTION, Issue 9 2010
David E. Nelson
ABSTRACT Aims Assess long-term trends of the correlation between alcohol sales data and survey data. Design Analyses of state alcohol consumption data from the US Alcohol Epidemiologic Data System based on sales, tax receipts or alcohol shipments. Cross-sectional, state annual estimates of alcohol-related measures for adults from the US Behavioral Risk Factor Surveillance System using telephone surveys. Setting United States. Participants State alcohol tax authorities, alcohol vendors, alcohol industry (sales data) and randomly selected adults aged , 18 years 1993,2006 (survey data). Measurements State-level per capita annual alcohol consumption estimates from sales data. Self-reported alcohol consumption, current drinking, heavy drinking, binge drinking and alcohol-impaired driving from surveys. Correlation coefficients were calculated using linear regression models. Findings State survey estimates of consumption accounted for a median of 22% to 32% of state sales data across years. Nevertheless, state consumption estimates from both sources were strongly correlated with annual r-values ranging from 0.55,0.71. State sales data had moderate-to-strong correlations with survey estimates of current drinking, heavy drinking and binge drinking (range of r-values across years: 0.57,0.65; 0.33,0.70 and 0.45,0.61, respectively), but a weaker correlation with alcohol-impaired driving (range of r-values: 0.24,0.56). There were no trends in the magnitude of correlation coefficients. Conclusions Although state surveys substantially underestimated alcohol consumption, the consistency of the strength of the association between sales consumption and survey data for most alcohol measures suggest both data sources continue to provide valuable information. These findings support and extend the distribution of consumption model and single distribution theory, suggesting that both sales and survey data are useful for monitoring population changes in alcohol use. [source]


Evaluation of the use of dried spots and of different storage conditions of plasma for HIV-1 RNA quantification

HIV MEDICINE, Issue 6 2007
B Amellal
Objectives The aim of the study was to evaluate the use of dried plasma spots to determine HIV-1 RNA viral loads. Methods The viral loads of 30 liquid plasma samples were compared with those of corresponding dried plasma spots on filter paper (DPS-FP) and in tubes (DPS-T), both of which were left for 7 days at 22°C. Also, 10 liquid plasma samples with detectable viral load were stored at 4, 22 or 37°C for 7 days and five further liquid plasma samples were air-dried for up to 54 h to assess the effects of temperature and the drying step on HIV-1 viral load. Results The viral loads of the 30 liquid plasma samples correlated significantly with those of the paired dried spots DPS-FP and DPS-T, but with median losses of 0.64 and 0.69 log10 HIV-1 RNA copies/mL, respectively, and a limit of detection of 3 log10 copies/mL. The 10 liquid plasma samples stored for 1 week at 37°C showed a weaker correlation and had a significantly reduced median viral load (,0.92 log10; P=0.005) when compared with the viral load of the matched plasma stored at ,80°C. Most of the loss happened during the drying step. Conclusions Reliable measurement of HIV-1 RNA viral load requires good plasma storage conditions. HIV RNA stability was affected by desiccation and 1 week of storage at 37°C. However, our findings suggest that liquid plasma can be kept at 4 or 22°C for a week with no effect on viral load. [source]


The role of edema and demyelination in chronic T1 black holes: A quantitative magnetization transfer study,

JOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 2 2005
Ives Levesque MSc
Abstract Purpose To use quantitative magnetization transfer imaging (qMTI) in an investigation of T1 -weighted hypointensity observed in clinical magnetic resonance imaging (MRI) scans of multiple sclerosis (MS) patients, which has previously been proposed as a more specific indicator of tissue damage than the more commonly detected T2 hyperintensity. Materials and Methods A cross-sectional study of 10 MS patients was performed using qMTI. A total of 60 MTI measurements were collected in each patient at a resolution of 2 × 2 × 7 mm, over a range of saturation pulses. The observed T1 and T2 were also measured. qMT model parameters were estimated using a voxel-by-voxel fit. Results A total of 65 T2 -hyperintense lesions were identified; 53 were also T1 hypointense. In these black holes, the qMTI-derived semisolid pool fraction F correlated negatively with T1,obs (r2 = 0.76; P < 0.0001). The water pool absolute size (PDf) showed a weaker correlation with T1,obs (positive, r2 = 0.53; P < 0.0001). The magnetization transfer ratio (MTR) showed a similarly strong correlation with F and a weaker correlation with PDf (r2 = 0.18; P < 0.04). Conclusion T1 increases in chronic black holes strongly correlated with the decline in semisolid pool size, and somewhat less to the confounding effect of edema. MTR was less sensitive than T1,obs to liquid pool changes associated with edema. J. Magn. Reson. Imaging 2005;21:103,110. © 2005 Wiley-Liss, Inc. [source]


Intrahepatic expression of the hepatic stellate cell marker fibroblast activation protein correlates with the degree of fibrosis in hepatitis C virus infection

LIVER INTERNATIONAL, Issue 2 2002
MT Levy
Abstract: Background: Activated hepatic stellate cells (HSCs), recognised by their , smooth muscle actin immunoreactivity, are primarily responsible for liver fibrosis. However, the presence of , smooth muscle actin positive HSCs is not always associated with the development of liver fibrosis. Recently, other markers of human HSCs including the gelatinase fibroblast activation protein (FAP) and glial fibrillary acidic protein have been identified. Aims: We examined the relationship between the expression of these HSC markers and the severity of liver injury in patients with chronic hepatitis C virus infection. Methods: Liver tissue from 27 patients was examined using immunohistochemistry. Linear correlation analysis was used to compare staining scores with the stage and grade of liver injury. Results,Conclusions: FAP expression, seen at the tissue-remodelling interface, was strongly and significantly correlated with the severity of liver fibrosis. A weaker correlation was seen between glial fibrillary acidic protein expression and fibrosis stage. This contrasted with the absence of a relationship between , smooth muscle actin and the fibrotic score. A correlation was also observed between FAP expression and necroinflammatory score. In summary, FAP expression identifies a HSC subpopulation at the tissue-remodelling interface that is related to the severity of liver fibrosis. [source]


Quantitative analysis of spatial proteoglycan content in articular cartilage with Fourier transform infrared imaging spectroscopy: Critical evaluation of analysis methods and specificity of the parameters

MICROSCOPY RESEARCH AND TECHNIQUE, Issue 5 2010
L. Rieppo
Abstract Objective: To evaluate the specificity of the current Fourier transform infrared imaging spectroscopy (FT-IRIS) methods for the determination of depthwise proteoglycan (PG) content in articular cartilage (AC). In addition, curve fitting was applied to study whether the specificity of FT-IRIS parameters for PG determination could be improved. Methods: Two sample groups from the steer AC were prepared for the study (n = 8 samples/group). In the first group, chondroitinase ABC enzyme was used to degrade the PGs from the superficial cartilage, while the samples in the second group served as the controls. Samples were examined with FT-IRIS and analyzed using previously reported direct absorption spectrum techniques and multivariate methods and, in comparison, by curve fitting. Safranin O-stained sections were measured with digital densitometry to obtain a reference for depthwise PG distribution. Results: Carbohydrate region-based absorption spectrum methods showed a statistically weaker correlation with the PG reference distributions than the results of the curve fitting (subpeak located approximately at 1,060 cm,1). Furthermore, the shape of the depthwise profiles obtained using the curve fitting was more similar to the reference profiles than with the direct absorption spectrum analysis. Conclusions: Results suggest that the current FT-IRIS methods for PG analysis lack the specificity for quantitative measurement of PGs in AC. The curve fitting approach demonstrated that it is possible to improve the specificity of the PG analysis. However, the findings of the present study suggest that further development of the FT-IRIS analysis techniques is still needed. Microsc. Res. Tech. 2010. © 2009 Wiley-Liss, Inc. [source]


A statistical comparison of pad numbers versus pad weights in the quantification of urinary incontinence,

NEUROUROLOGY AND URODYNAMICS, Issue 1 2007
Drew A. Dylewski
Abstract Aims Pad per day (PPD) usage is a frequently utilized measure of urinary incontinence. The 24-hour pad weight test (24PWT) is a reproducible test for quantifying incontinence volumes. We investigated whether PPD validly reports the magnitude of urinary incontinence. Methods This was a retrospective review of patients undergoing stress incontinence surgery from July 2002 to 2005. Inclusion criteria were a documented 24PWT and patient-reported PPD usage. Grams of urine loss per pad (GPP) provided a third measure of incontinence. Descriptive statistics and correlations between all variables and significance were noted. Factor analysis was performed on the three measures of leakage and age for all patients over age 50. Results One hundred forty-five male and 116 female patients met inclusion criteria. Correlated against 24PWT, GPP has the strongest association with a correlation of 0.80 for males and 0.88 for females. PPD has a weaker correlation of 0.64 for males and 0.61 for females (R2,=,0.38 overall). Factor analysis identified two components associated with incontinence. A "leakage" component correlated best with 24PWT and GPP. Additionally, an "age" component implies that despite stable 24PWT values, older patients increase GPP while PPD decreases. Conclusions Self-reported PPD is an unreliable measure of incontinence as this variable only measures 38% of the variation of urinary incontinence volume. Patients at a given PPD level present with a wide range of 24PWT values. Older patients have higher per-pad leakage. Future incontinence studies should report 24PWT to ensure the most reliable and uniform data. Neurourol. Urodynam. © 2006 Wiley-Liss, Inc. [source]


Serum concentration of macrophage-derived chemokine may be a useful inflammatory marker for assessing severity of atopic dermatitis in infants and young children

PEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 4 2003
Ting Fan Leung
Chemokines are responsible for the trafficking of leukocytes to sites of inflammation. Serum chemokine levels were previously shown to be increased in adult patients with atopic dermatitis (AD). We tested whether serum concentrations of chemokines, including macrophage-derived chemokine (MDC), thymus and activation-regulated chemokine (TARC), eotaxin (EOX), interferon gamma inducible protein 10 (IP-10) and monocyte chemotactic protein 1 (MCP-1), are useful inflammatory markers for assessing AD severity in infants and young children. To investigate this, we assessed the severity of AD clinically using the SCORing Atopic Dermatitis (SCORAD) index system. Serum chemokine concentrations were determined by sandwich enzyme immunoassay. Twenty AD patients with a median age of 2.1 years [interquartile range (IQR): 0.6,4.2] were recruited. Their SCORAD score was 23.5 (12.5,33.5). Serum concentrations of MDC, TARC, EOX, IP-10 and MCP-1 were 2551 (1978,3935), 1469 (1125,3070), 68 (57,85), 126 (101,226) and 518 (419,614) pg/ml, respectively. Serum MDC levels correlated with SCORAD (r =,0.608, p = 0.004) and its extent (r =,0.629, p = 0.003) and intensity (r =,0.557, p = 0.011) components. Serum TARC concentration showed weaker correlation with extent (r =,0.474, p = 0.035) and intensity (r =,0.465, p = 0.039) of skin involvement but not SCORAD. The median serum levels of MDC (3131 vs. 2394 pg/ml; p = 0.031) and EOX (80 vs. 61 pg/ml; p = 0.046) were also higher in children with moderate as compared with mild AD. The other chemokines did not correlate with AD severity. In conclusion, our results suggest that serum MDC concentration may be a useful inflammatory marker for assessing AD severity in infants and young children. [source]


The FLACC behavioral scale for procedural pain assessment in children aged 5,16 years

PEDIATRIC ANESTHESIA, Issue 8 2008
STEFAN NILSSON MSN RN
Summary Objectives:, To evaluate the concurrent and construct validity and the interrater reliability of the Face, Legs, Activity, Cry and Consolability (FLACC) scale during procedural pain in children aged 5,16 years. Background:, Self-reporting of pain is considered to be the primary source of information on pain intensity for older children but a validated observational tool will provide augment information to self-reports during painful procedures. Methods:, Eighty children scheduled for peripheral venous cannulation or percutaneous puncture of a venous port were included. In 40 cases two nurses simultaneously and independently assessed pain by using the FLACC scale and in 40 cases one of these nurses assessed the child. All children scored the intensity of pain by using the Coloured Analogue Scale (CAS) and distress by the Facial Affective Scale (FAS). Results:, Concurrent validity was supported by the correlation between FLACC scores and the children's self-reported CAS scores during the procedure (r = 0.59, P < 0.05). A weaker correlation was found between the FLACC scores and children's self-reported FAS (r = 0.35, P < 0.05). Construct validity was demonstrated by the increase in median FLACC score to 1 during the procedure compared with 0 before and after the procedure (P < 0.001). Interrater reliability during the procedure was supported by adequate kappa statistics for all items and for the total FLACC scores (, = 0.85, P < 0.001). Conclusions:, The findings of this study support the use of FLACC as a valid and reliable tool for assessing procedural pain in children aged 5,16 years. [source]


Preoperative Differences Between Male and Female Patients With Sleep Apnea,

THE LARYNGOSCOPE, Issue 9 2001
Regina Paloyan Walker MD
Abstract Objectives/Hypothesis To evaluate the differences between female and male patients with obstructive sleep apnea syndrome (OSAS) in the preoperative period. Study Design Nonrandomized cross-sectional study. Methods An analysis of 686 patients (111 women and 575 men) with OSAS was completed. Multivariate modeling techniques were employed to correlate gender with the preoperative respiratory disturbance index (RDI), apnea index (AI), hypopnea index (HI), body mass index (BMI), age, and initial symptoms. Results At presentation, the male patients were significantly younger and had a lower BMI and a higher RDI and AI than the female patients. For the entire OSAS population studied, the RDI increased as the BMI increased (correlation coefficient [r] = 0.35, P = <.001). For the female patients there was a weaker correlation (r = 0.21, P = .034), and in male patients there was a stronger correlation (r = 0.40, P <.001). For the entire population there was a negative correlation between age and RDI (r = ,0.15, P <.001). In female patients there was a nonsignificant correlation (r = ,0.09, P = .35), and in male patients the correlation was significant (r = ,0.16, P <.001). There was no difference in the reporting of the number of symptoms based on gender (P = .355). Female patients noted headaches on awakening more commonly than male patients (P = .001), and male patients noted snoring (P = .014) and stopping breathing during sleep (P = .001) more often than female patients. Conclusions The analysis demonstrated that within a surgical population sample, gender differences exist. The findings of this series were as follows: 1) Apnea severity in women was less weight-dependent than in men; (2) in men there was a significant negative correlation between age and apnea severity; and (3) female and male patients reported the same number of signs or symptoms on presentation, although certain signs and symptoms were more commonly reported based on gender. Current clinical evaluation practices must take into account this gender disparity. [source]


Association between corneal hysteresis and central corneal thickness in glaucomatous and non-glaucomatous eyes

ACTA OPHTHALMOLOGICA, Issue 8 2009
George Mangouritsas
Abstract. Purpose:, We aimed to determine corneal hysteresis values (CH) using the ocular response analyser (ORA) in non-glaucomatous and glaucomatous eyes and their relationship with central corneal thickness (CCT). Methods:, Corneal hysteresis, intraocular pressure (IOP) as measured by Goldmann applanation tonometry (GAT) and CCT were prospectively evaluated in 74 non-glaucoma subjects with IOP < 21 mmHg and in 108 patients with treated primary open-angle glaucoma (POAG). One eye in each subject was randomly selected for inclusion in the analysis. Results:, Mean (± standard deviation [SD]) age was 59.2 ± 14.2 years in the non-glaucoma group and 62.4 ± 9.8 years in the glaucoma group. Mean (± SD) GAT IOP was 15.7 ± 2.65 mmHg and 16.38 ± 2.73 mmHg in the non-glaucoma and glaucoma groups, respectively. There was no statistically significant difference between the two groups in mean age (p = 0.396) or mean GAT IOP (p = 0.098). Mean (± SD) CH was 10.97 ± 1.59 mmHg in the non-glaucoma and 8.95 ± 1.27 mmHg in the glaucoma groups, respectively. The difference in mean CH between the two groups was statistically significant (p < 0.0001). There was a strong positive correlation between CH and CCT in the non-glaucoma group (r = 0.743) and a significantly (p = 0.001) weaker correlation (r = 0.426) in the glaucoma group. Conclusions:, Corneal hysteresis was significantly lower in eyes with treated POAG than in non-glaucomatous eyes. The corneal biomechanical response was strongly associated with CCT in non-glaucoma subjects, but only moderately so in glaucoma patients. It can be assumed that diverse structural factors, in addition to thickness, determine the differences in the corneal biomechanical profile between non-glaucomatous and glaucomatous eyes. Corneal hysteresis could be a useful tool in the diagnosis of glaucoma. [source]


Spatial variation of ammonia volatilization from soil and its scale-dependent correlation with soil properties

EUROPEAN JOURNAL OF SOIL SCIENCE, Issue 6 2008
R. Corstanje
Summary Quantitative predictions of ammonia volatilization from soil are useful to environmental managers and policy makers and empirical models have been used with some success. Spatial analysis of the soil properties and their relationship to the ammonia volatilization process is important as predictions will be required at disparate scales from the field to the catchment and beyond. These relationships are known to change across scales and this may affect the performance of an empirical model. This study is concerned with the variation of ammonia volatilization and some controlling soil properties: bulk density, volumetric water content, pH, CEC, soil pH buffer power, and urease activity, over distances of 2, 50, 500, and >2000 m. We sampled a 16 km × 16 km region in eastern England and analyzed the results by a nested analysis of (co)variance, from which variance components and correlations for each scale were obtained. The overall correlations between ammonia volatilization and the soil properties were generally weak: ,0.09 for bulk density, 0.04 for volumetric water content, ,0.22 for CEC, ,0.08 for urease activity, ,0.22 for pH and 0.18 for the soil pH buffer power. Variation in ammonia volatilization was scale-dependent, with substantial variance components at the 2- and 500-m scales. The results from the analysis of covariance show that the relationships between ammonia volatilization and soil properties are complex. At the >2000 m scale, ammonia volatilization was strongly correlated with pH (,0.82) and CEC (,0.55), which is probably the result of differences in parent material. We also observed weaker correlations at the 500-m scale with bulk density (,0.61), volumetric water content (0.48), urease activity (,0.42), pH (,0.55) and soil pH buffer power (0.38). Nested analysis showed that overall correlations may mask relationships at scales of interest and the effect of soil variables on these soil processes is scale-dependent. [source]


Variability of southeastern Queensland rainfall and climate indices

INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 6 2004
Bradley F. Murphy
Abstract The variability of climate indices and rainfall in southeastern (SE) Queensland (Qld) is studied. Using high-resolution gridded rainfall data for all of Australia and global sea-surface temperatures (SSTs), the relationship between Australia-wide rainfall (and in SE Qld in particular) and SST indices and the southern oscillation index (SOI) have been investigated. It is found that SE Qld is more subject to the breakdown of correlations between the SOI and rainfall than any other part of Australia. Model predictions suggest that this is probable in the future. Considering only time scales longer than interannual, it was found that SSTs in the central tropical Pacific Ocean (TPO; represented by the Niño-4 index) correlated best with SE Qld rainfall. Eastern TPO (Niño-3) SSTs and the SOI produced successively weaker correlations. The time series of the second modes of variability of SSTs over the Pacific and Indian Oceans were shown to have limited impact on SE Qld rainfall variability. The data were split into periods before and after 1946, when Australian mean rainfall changed. Whereas the SOI correlations with rainfall in SE Australia were similar in both periods, in SE Qld the correlations were very weak in the earlier period (0.06) but very strong in the later period (0.72). The Niño-4 index correlated better than the Niño-3 index in both periods, but both indexes showed smaller changes from the earlier to the later periods than the SOI. Copyright © 2004 Royal Meteorological Society. [source]


Strong relationship between NT-proXNP levels and cardiac output following cardiac surgery in neonates and infants

ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 4 2010
T. BREUER
Background: NT-proXNP, a new natriuretic peptide analyte, incorporates information about the concentrations of both N-terminal pro-atrial and pro-brain natriuretic peptides (NT-proANP, NT-proBNP). We aimed to investigate whether NT-proXNP is a reliable indicator of the cardiac index (CI) and the hemodynamic state in neonates and infants undergoing an open heart surgery. Methods: We enrolled 26 children under the age of 1 year into this prospective study. All patients underwent an elective cardiac operation with cardiopulmonary bypass (CPB) to achieve complete biventricular repair. Peri-operative hemodynamic parameters were assessed by transpulmonary thermodilution and natriuretic peptide levels were recorded. Results: The NT-proXNP level correlated significantly with the simultaneously measured NT-proANP level (r=0.60, P<0.001), but more strongly with the NT-proBNP level (r=0.89, P<0.001) and the arithmetic sum of both (r=0.88, P<0.001). NT-proXNP had a strong correlation with CI (r=,0.85, P<0.001), the stroke volume index (r=,0.80, P<0.001) and the global ejection fraction (r=,0.67, P<0.009) throughout the post-operative period. Conventionally measured parameters such as heart rate, mean arterial pressure and pulse-pressure product exhibited weaker correlations with CI than NT-proXNP. Among laboratory values, creatinine levels correlated significantly with CI (r=,0.77, P<0.001) and NT-proXNP (r=0.76, P<0.001) during the post-operative period. A post-operative NT-proXNP level of 3079 pmol/l was diagnostic for CI <3 l/min/m2 with 89% sensitivity and 90% specificity (area under the curve: 0.91 ± 0.05). Conclusion: NT-proXNP is a good marker of cardiac output following pediatric cardiac surgery and might be a useful tool in the recognition of a low output state. [source]


Early-type stars observed in the ESO UVES Paranal Observatory Project , I. Interstellar Na i UV, Ti ii and Ca ii K observations,

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2006
I. Hunter
ABSTRACT We present an analysis of interstellar Na i (,air= 3302.37 and 3302.98 Å), Ti ii(,air= 3383.76 Å) and Ca ii K (,air= 3933.66 Å) absorption features for 74 sightlines towards O- and B-type stars in the Galactic disc. The data were obtained from the Ultraviolet and Visual Echelle Spectrograph Paranal Observatory Project, at a spectral resolution of 3.75 km s,1 and with mean signal-to-noise ratios per pixel of 260, 300 and 430 for the Na i, Ti ii and Ca ii observations, respectively. Interstellar features were detected in all but one of the Ti ii sightlines and all of the Ca ii sightlines. The dependence of the column density of these three species with distance, height relative to the Galactic plane, H i column density, reddening and depletion relative to the solar abundance has been investigated. We also examine the accuracy of using the Na i column density as an indicator of that for H i. In general, we find similar strong correlations for both Ti and Ca, and weaker correlations for Na. Our results confirm the general belief that Ti and Ca occur in the same regions of the interstellar medium (ISM) and also that the Ti ii/Ca ii ratio is constant over all parameters. We hence conclude that the absorption properties of Ti and Ca are essentially constant under the general ISM conditions of the Galactic disc. [source]


Les hedge funds ont-ils leur place dans un portefeuille institutionnel canadien?

CANADIAN JOURNAL OF ADMINISTRATIVE SCIENCES, Issue 3 2003
Stéphanie Desrosiers
This article examines the return and risk of hedge funds (HF), and their correlations with traditional asset classes for the 1990,2002 period. Efficient frontiers resulting from optimizations with and without constraints demonstrate that it is worthwhile to include HF in a Canadian institutional investor's portfolio. HF offer a high potential return relative to risk, while weaker correlations with traditional asset classes create a beneficial diversification effect. Non-directional HF provide protection in bear markets and are more suitable for lower risk portfolios, whereas directional HF are better suited to higher risk portfolios. Caveats are necessary due to the skew-ness and kurtosis of the return distributions, potential biases in the return series, the lower liquidity, and the complexity of the HF industry. Résumé Cet article examine le rendement, le risque et les correélations des hedge funds (HF) avec les catégories d'actif traditionnelles sur la période 1990,2002. Des optimisations avec et sans contraintes montrent qu'il est avantageux d'inclure les HF dans un portefeuille institutionnel canadien du fait d'un potentiel de rendement élevé par rapport au risque encouru et de faibles corrélations. Les HF non-directionnels offrent une meilleure protection en marché baissier et sont plus appropriés pour des portefeuilles moins risqués. Les HF directionnels conviennent davantage aux portefeuilles prksentant un risque plus élevé. Des réserves doivent toutefois étre émises en raison des coefficients d'asymétrie et d'aplatissement de la distribution des rendements, des biais potentiels des données, de la faible liquidité, et de la complexité de l'industrie des HF. [source]


Association between androgens, intima-media thickness and the metabolic syndrome in obese adolescent girls

CLINICAL ENDOCRINOLOGY, Issue 6 2010
Gideon De Sousa
Summary Background, While an association between androgens and the metabolic syndrome (MS) is well established in obese women, studies concerning this relationship are scarce in obese adolescent girls. Therefore, we analysed the relationships between androgens, MS and intima-media thickness (IMT) in this age-group. Methods, In 160 obese girls (aged 12,18 years, mean BMI: 32·6 ± 5·0 kg/m2), androgens [testosterone, dehydroepiandrosterone sulphate (DHEA-S), androstenedione], SHBG and the components of MS (waist circumference, blood pressure (BP), lipids, uric acid, insulin, glucose, 2 h glucose in oral glucose tolerance test (oGTT)) were studied. Furthermore, IMT was determined in a subgroup of 71 randomly chosen girls. Results, Testosterone correlated significantly to systolic BP (r = 0·20), diastolic BP (r = 0·24), 2 h glucose in oGTT (r = 0·30), triglycerides (r = 0·19), uric acid (r = 0·17), waist circumference (r = 0·25) and IMT (r = 0·54). These relationships (except for waist circumference and uric acid) were independent of BMI and insulin resistance index homeostasis model assessment. In contrast to testosterone, DHEA-S, androstenedione and SHBG showed no or weaker correlations to any parameter of MS. The 48 girls with MS demonstrated significantly higher testosterone (1·8 ± 0·7 nmol/l; P = 0·025) and DHEA-S (4·7 ± 2·3 ,mol/l; P = 0·008) concentrations as compared with the 112 girls without MS (mean testosterone 1·5 ± 0·7 nmol/l, mean DHEA-S 3·6 ± 2·3 ,mol/l). Conclusions, Testosterone was significantly related to MS and its components in obese adolescent girls independently of BMI and insulin resistance. As IMT was significantly associated with testosterone, this supports the clinical relevance of this finding. [source]