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Longitudinal Observational Study (longitudinal + observational_study)
Selected AbstractsComparing the effects of entertainment media and tobacco marketing on youth smoking in GermanyADDICTION, Issue 5 2009James D. Sargent ABSTRACT Aims To examine differential effects of smoking in films and tobacco advertising on adolescent smoking. We hypothesize that movie smoking will have greater effects on smoking initiation, whereas tobacco advertising receptivity will primarily affect experimentation. Design Longitudinal observational study of adolescents. Setting School-based surveys conducted in Schleswig-Holstein, Germany. Participants A total of 4384 adolescents age 11,15 years at baseline and re-surveyed 1 year later; ever smoking prevalence was 38% at time 1. Measurements The main outcome variable combined two items assessing life-time and current smoking (alpha = 0.87). Baseline never smokers were analyzed separately from those who had tried smoking (ever smokers). Exposure to smoking in 398 internationally distributed US movies was modeled as a continuous variable, with 0 corresponding to the 5th percentile and 1 to the 95th percentile of exposure. Tobacco marketing receptivity consisted of naming a brand for a favorite tobacco advertisement. Ordinal logistic regressions controlled for socio-demographics, other social influences, personality characteristics of the adolescent and parenting style. Findings Whereas 34% of ever smokers were receptive to tobacco marketing at time 1, only 6% of never smokers were. Among time 1 never smokers, exposure to movie smoking was a significantly stronger predictor of higher time 2 smoking level [adjusted proportional odds ratio = 2.76, 95% confidence interval (1.84, 4.15)] than was tobacco marketing receptivity (1.53 [1.07, 2.20]). Among time 1 ever smokers, both tobacco marketing receptivity and exposure to movie smoking predicted higher levels of time 2 smoking [2.17 (1.78, 2.63) and 1.62 (1.18, 2.23), respectively], and the two estimates were not significantly different. Conclusions In this longitudinal study, exposure to movie smoking was a stronger predictor of smoking initiation than tobacco marketing receptivity, which was more common among ever smokers. The results suggest that entertainment media smoking should be emphasized in programs aimed at preventing onset, and both exposures should be emphasized in programs aimed at experimental smokers. [source] Association of Season and Pasture Grazing with Blood Hormone and Metabolite Concentrations in Horses with Presumed Pituitary Pars Intermedia DysfunctionJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 5 2010N. Frank Background: Pituitary pars intermedia dysfunction (PPID) is a risk factor for pasture-associated laminitis, which follows a seasonal pattern. Hypothesis: Hormonal responses to season differ between PPID and unaffected horses. Animals: Seventeen horses aged 8,30 years (14 horses , 20 years of age). Methods: Longitudinal observational study. Blood was collected monthly from August 2007 until July 2008 after pasture grazing and again after overnight stall confinement. Blood hormone and metabolite concentrations were measured and pasture grass samples were analyzed to determine carbohydrate content. Analysis of variance analysis for repeated measures was performed. Results: Mean ACTH concentrations varied significantly over time (P < .001), with higher concentrations detected in August, September, and October compared with November,April. Pasture × time effects were detected for glucose and insulin concentrations, with peaks observed in September. Horses were retrospectively allocated to PPID (n = 8) and control (n = 9) groups on the basis of plasma ACTH concentrations. Changes in insulin concentrations over time differed in the PPID group when compared with the control group. Insulin concentrations were positively correlated with grass carbohydrate composition. Conclusions and Clinical Importance: PPID did not affect the timing or duration of the seasonal increase in ACTH concentrations, but higher values were detected in affected horses. Insulin concentrations differed between groups, but hyperinsulinemia was rarely detected. Glucose and insulin concentrations peaked in September when horses were grazing on pasture, which could be relevant to the seasonal pattern of laminitis. [source] A longitudinal observational study of insulin therapy and glycaemic control in Scottish children with Type 1 diabetes: DIABAUD 3DIABETIC MEDICINE, Issue 11 2006Scottish Study Group for the Care of the Young with Diabetes Abstract Objective/background, Our objective was to investigate glycaemic control in children with Type 1 diabetes in Scotland and to analyse the effect of changing ,conventional' insulin regimen strategies on outcome. DIABAUD 2 (1997,1998) (D2) demonstrated that average glycaemic control in young people with Type 1 diabetes in Scotland was poor, with mean HbA1c of 9.0%. Over 90% were then treated with a twice-daily insulin regimen. The aim of DIABAUD 3 (2002,2004) (D3) was to determine if control had improved, and to examine changes in insulin regimen and effects on glycaemic control. Methods, In DIABAUD 3, data were collected prospectively on children aged < 15 years. in nine out of 15 centres throughout Scotland. HbA1c on 986 subjects was measured in a single Diabetes Control and Complications Trial-aligned laboratory. The results were compared with those from DIABAUD 2, for the same nine centres. Multiple regression comparison was performed to adjust for imbalance in relevant confounders (e.g. age, duration, height and weight, insulin dose and centre). Results, For D3, the age range was 1.1,14.9 years (62% aged 10,14 years), mean (± sd) HbA1c 9.2% ± 1.5 (compared with D2, 9.0% ± 1.5). Only 9.7% achieved the target of HbA1c < 7.5%. The number of subjects in D3 on twice-daily injections was 51% (compared with 94% in D2), 43% on three-times-daily injections (2% in D2) and 2.3% on four or more (1.9% in D2): HbA1c did not differ in these groups. In both the D2 and D3 cohorts, HbA1c rose with age. After adjustment for other variables in the combined datasets, insulin regimen was not a significant predictor of HbA1c (F = 0.19, d.f. = 3, 1774; P = 0.90). Conclusion, The glycaemic control in young people in Scotland remains poor and above the national target. Over 4 years, moderate intensification of insulin therapy (i.e. from two to three injections each day, usually reflecting splitting of the evening dose) across the population failed to improve the average HbA1c and reduce the increase seen with age. A national programme away from ,conventional' to an ,intensive' regimen of insulin therapy is required. [source] A longitudinal observational study of a cohort of patients with relapsing,remitting multiple sclerosis treated with glatiramer acetateEUROPEAN JOURNAL OF NEUROLOGY, Issue 11 2007M. Debouverie Immunomodulatory treatments for relapsing,remitting multiple sclerosis (RRMS) are not efficacious or tolerated in all patients. It is important to evaluate alternative classes of treatment in patients failing first-line therapy. The objective of this prospective observational study was to evaluate the efficacy and safety of glatiramer acetate in patients, to whom , -interferons could not be administered. The study included patients with RRMS who were intolerant to or had contraindications to , -interferon. After initiation of glatiramer acetate treatment, follow-up visits were made every 3 months, when data on neurologist-ascertained relapses and disability [Expanded Disability Status Scale (EDSS) score] were collected. Tolerability was evaluated by spontaneous adverse event reporting. Overall, 205 patients were studied and 113 (55.1%) treated for at least 4 years. The proportion of patients presenting over three relapses per year decreased from 51.2% to 8.4% in the 2 years following treatment initiation. Over 5 years of treatment, mean annualized relapse rates and mean EDSS scores remained stable (0.4,0.6 relapses/year and 3.6 ± 1.8,3.3 ± 2.1 respectively). Adverse events were reported by 179 patients, leading to discontinuation of treatment in 10 patients. Patients with RRMS to whom , -interferons cannot be prescribed can benefit from treatment with glatiramer acetate. [source] Rationale, design and methods of the OSCAR study: observational study on cognitive function and systolic blood pressure reduction in hypertensive patientsFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 2 2007Atul Pathak Abstract Data from several recent clinical trials have suggested a beneficial effect of antihypertensive medications on preservation of cognitive function. Eprosartan, an angiotensin type-1 receptor antagonist (ARA) with dual action on both pre- and postsynaptic angiotensin type 1 receptors, may be effective in the control of SBP and the prevention of cognitive decline. The OSCAR (Observational Study on Cognitive function And SBP Reduction) study is an international longitudinal observational study with a duration of 6 months intended to examine the impact of the ARA eprosartan on cognitive function (assessed using the Mini-Mental State Examination [MMSE]) and control of systolic blood pressure (SBP) in a large international population of hypertensive patients managed in a standard primary care setting. A total of 100 000 hypertensive patients, aged ,50 years and with SBP of >140 mmHg will be recruited by more than 20 000 primary care physicians in 27 countries. These patients will receive eprosartan 600 mg once a day for 6 months. The MMSE, a globally validated cognitive screening test, will be performed at baseline, and after 6 months of treatment. After the first month of monotherapy, eprosartan treatment may, at the absolute discretion of individual investigators, be supplemented with other antihypertensive medications for the remainder of the study. The primary outcome indices are the mean relative change in MMSE score and the absolute change from baseline in SBP in the study population as a whole and in subsets of patients according to various factors among them: ethnicity, comorbidities (i.e. target organ damage, diabetes), baseline cognitive level and baseline blood pressure level. The secondary objectives are to identify factors influencing SBP and MMSE changes. The OSCAR trial is the first international observational study focusing on MMSE in a wide international cohort of hypertensive patients. The results are expected in 2007. [source] Use of the Late-Life Function and Disability Instrument to Assess Disability in Major DepressionJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 9 2009Jordan F. Karp MD OBJECTIVES: To determine whether there was greater disability in subjects with depression than in those without, the correlation between disability and depression severity and quality of life, and whether improvement in disability after antidepressant pharmacotherapy was greater in those who responded to antidepressant treatment. DESIGN: Disability in subjects with and without depression from two different studies was compared for 22 weeks. Correlations were performed for the subjects with depression between disability and depression, anxiety, health-related quality of life (HRQOL), and medical comorbidity. T -tests were used to compare disability between subjects who did and did not respond to antidepressant treatment and change in disability after pharmacotherapy. SETTING: Late-life depression research clinic. PARTICIPANTS: The 313 subjects were recruited from primary care and the community and were aged 60 and older; 244 subjects were participants in a depression treatment protocol, and 69 subjects without depression participated in a separate longitudinal observational study of the mental and cognitive health of depression-free older adults. MEASUREMENTS: The Late-Life Function and Disability Instrument (LL-FDI), a measure of instrumental activity of daily living, personal role, and social role functioning. RESULTS: Subjects with depression scored lower than controls for domains measuring limitation (can do) and frequency (does do) of activities. Both disability domains correlated with depression severity, anxiety, HRQOL, and cognition. Disability improved with antidepressant treatment; for partial responders who continued to receive higher-dose antidepressant treatment out to 22 weeks, there was continued improvement, although not to the level of comparison subjects without depression. CONCLUSION: The LL-FDI appears to discriminate subjects with depression from those without, correlates with depression severity, and demonstrates sensitivity to antidepressant treatment response. We recommend further investigation of the LL-FDI and similar disability instruments for assessing depression-related disability. [source] Use of Auscultation and Doppler Echocardiography in Boxer Puppies to Predict Development of Subaortic or Pulmonary StenosisJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 1 2009S. Jenni Background: Boxers are predisposed to subaortic and pulmonic stenosis (SAS, PS). Screening of puppies may be useful in estimating the risk of their developing a defect that potentially compromises life expectancy or exercise tolerance. Hypothesis: Presence of SAS or PS in adult Boxers can be predicted by auscultation and Doppler echocardiography at 9,10 weeks of age. Animals: Eighty-five Boxer puppies examined at 9,10 weeks of age and at 12 months of age. Methods: Prospective, longitudinal observational study. Auscultation by stethoscope and continuous wave-Doppler echocardiography for peak velocities (Vmax) in the aorta (Ao) and pulmonary artery (PA). Results: Intensity of heart murmurs in puppies correlated with VmaxAo and VmaxPA in adults. VmaxAo and VmaxPA in puppies correlated with VmaxAo and VmaxPA in adults, respectively. From puppy to adult, VmaxAo increased and VmaxPA remained unchanged. The negative predictive value for absent or only a soft (,II/VI) murmur in puppies being associated with VmaxAo and PA , 2.4 m/s as an adult was 90% and ,3.5 m/s 100%. The negative predictive value of a Vmax, 2.4 m/s as a puppy still being ,2.4 m/s as an adult was 94% for Ao and 96% for PA, and of a Vmax, 3.5 m/s, 99% for Ao and 100% for PA. Conclusions and Clinical Importance: Even though VmaxAo increases during growth in Boxer puppies, indicating relative narrowing of the aorta, puppies with VmaxAo , 2.4 m/s do not usually progress to clinically have relevant SAS at 12 months of age. [source] Pregnancy testing prior to sterilisationBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 11 2000Asha Kasliwal Specialist Registrar Objective To determine the incidence of positive pregnancy test on the day of laparoscopic sterilisation. Design Prospective longitudinal observational study. Setting Gynaecology unit in a UK teaching hospital. Sample Between 1 January 1997 and 31 December 1998, eight hundred and two consecutive women were admitted for laparoscopic sterilisation after assessment in the gynaecology clinic. On the day of planned surgery, all women had a pregnancy test performed on a urine sample taken that morning following overnight fasting, immediately prior to operation. Main outcome measures A positive pregnancy test on the day of planned surgery. Results Of 802 women tested, 21 (2.6%) were pregnant. A careful medical history taken before surgery revealed evidence of amenorrhoea and menstrual irregularity in 17 of the pregnant women. Of the 21 pregnant women, 11 underwent termination of pregnancy, six continued the pregnancy, four had a miscarriage and one had an ectopic pregnancy. Conclusion The routine practice of pregnancy testing on the day of laparoscopic sterilisation introduced in our hospital should continue to be part of a thorough clinical assessment before surgery. This may help to reduce the considerable level of existing litigation in a high risk area of gynaecological practice. [source] Results from the International Cataract Surgery Outcomes StudyACTA OPHTHALMOLOGICA, Issue thesis2 2007Jens Christian Norregaard MD Abstract It is widely accepted that cataract extraction with intraocular lens implantation is a highly effective and successful procedure. However, quality assessments and studies of effectiveness should still be undertaken. As with any surgical treatment modality, complications may occur, leading to suboptimal outcomes, additional health costs and deterioration in patients' functional capacity. International variation in clinical practice patterns and outcomes can serve as important pointers in the attempt to identify areas amenable to improvements in quality and cost-effectiveness. Once demonstrated, similar clinical results obtained in different health care systems can improve the level of confidence in a clinical standard against which the quality of care can be evaluated. The International Cataract Surgery Outcomes Study was established in 1992. The objective of this international comparative research project was to compare cataract management, outcomes of surgery and quality of care in four international sites. The study was conducted in the 1990s, since when many developments and refinements have emerged within cataract surgery. The actual figures reported in this thesis may no longer be of specific relevance as a decade has passed since their collection. However, the research questions and methods used in the study are still highly important and justify the publication of this report. The report deals with problems related to quality assessment, benchmarking, and the establishment and design of nationwide clinical databases , issues that are currently the focus of much attention. Moreover, the problems related to cross-national comparisons are increasingly relevant as more international databases are established. The study makes suggestions on how to report and compare objective as well as subjective criteria for surgery. The issue of how to report subjective criteria is a particular subject of current discussion. Four sites with high-quality health care systems were examined in this study: the USA, Denmark, the Province of Manitoba (Canada), and Barcelona (Spain). The design of the international research programme was based on methods developed by the US National Cataract Surgery Outcomes Study conducted by the US Cataract Patients Outcomes Research Team. The International Cataract Surgery Outcomes Study comprised three separate studies: a survey of ophthalmologists; a prospective cohort study, and a retrospective register-based cohort study. The survey study was based on data generated by a self-administered questionnaire completed by ophthalmologists in the four study areas. The questionnaire examined routine clinical practice involving patients considered for cataract surgery, and included questions on anaesthesia, monitoring and surgical techniques. The prospective cohort study was a large-scale, longitudinal observational study of patients undergoing first-eye cataract surgery in each study site. Patients were sampled consecutively from multiple clinics and followed for 4 months postoperatively. The retrospective cohort study was based on the Danish National Patient Register and claims data from the USA. This study could not be carried out in Barcelona or Manitoba as no suitable administrative databases were available. The papers based on register databases deal with retinal detachment and endophthalmitis but are not included in this thesis as the material was previously reported in my PhD thesis. The application of the studies was highly co-ordinated among the four sites and similar methods and instruments were used for data collection. The development of the data collection strategy, questionnaires, clinical data forms and data analyses were co-ordinated through weekly telephone conferences, annual in-person conferences, correspondence by mail or fax, and the exchange of sas programs and data files via the Internet. The survey study was based on responses from 1121 ophthalmologists in the four sites and results were presented in two papers. Within the previous year the participating ophthalmologists had performed a total of 212 428 cataract surgeries. With regard to preoperative ophthalmic testing, the present study reveals that refraction, fundus examination and A-scanning were performed routinely by most surgeons in all four sites. Other tests were reported to be performed routinely by some surgeons. It is unclear why any surgeon would use these other tests routinely in cataract patients with no ocular comorbidity. It appears that if this recommendation from the US Clinical Practice Guidelines Panel was broadly accepted, the use of these procedures and costs of care could be reduced, especially in Barcelona, the USA and Canada. Restricted use of medical screening tests was reported in Denmark. If this restricted screening were to be implemented in the USA, Canada and Barcelona, it would have significant resource implications. The most striking finding concerned the difference in monitoring practice between Denmark and each of the other three sites. In Denmark, monitoring equipment is seldom used and only occasionally is an anaesthesiologist present during cataract surgery. By contrast, in the other study sites, the presence of an anaesthesiologist using monitoring equipment is the norm. Adopting the Danish model in other sites would potentially yield significant cost savings. The results represent part of the background data used to inform the decision to conduct the two large-scale, multicentre Studies of Medical Testing for Cataract Surgery. The current study is an example of how surveys of clinical practice can pinpoint topics that need to be examined in randomized clinical trials. For the second study, 1422 patients were followed from prior to surgery until 4 months postoperatively. Preoperatively, a medical history was obtained and an ophthalmic examination of each patient performed. After consent had been obtained, patients were contacted for an in-depth telephone interview. The interview was repeated 4 months postoperatively. The interview included the VF-14, an index of functional impairment in patients with cataract. Perioperative data were available for 1344 patients (95%). The 4-month postoperative interview and clinical examination were completed by 1284 patients (91%). Main reasons for not re-evaluating patients were: surgery was cancelled (3%); refusal to participate (2%); lost to follow-up (1%), and death or being too sick (1%). The results have been presented in several papers, of which four are included in this thesis. One paper compared the preoperative clinical status of patients across the four sites and showed differences in both visual acuity (VA) and VF-14 measures. The VF-14 is a questionnaire scoring disability related to vision. The findings suggest that indications for surgery in comparable patients were similar in the USA and Denmark and were more liberal than in Manitoba and Barcelona. The results highlight the need to control for patient case mix when making comparisons among providers in a clinical database. This information is important when planning national databases that aim to compare quality of care. A feasible method may be to use one of the recently developed systems for case severity grading before cataract surgery. In another paper, perioperative clinical practice and rates of early complications following cataract surgery were compared across the four health care systems. Once again, the importance of controlling for case mix was demonstrated. Significant differences in clinical practice patterns were revealed, suggesting a general trend towards slower diffusion of new medical technology in Europe compared with North America. There were significant differences across sites in rates of intra- and early postoperative events. The most important differences were seen for rates of capsular rupture, hyphaema, corneal oedema and elevated pressure. Rates of these adverse events might potentially be minimized if factors responsible for the observed differences could be identified. Our results point towards the need for further research in this area. In a third paper, 4-month VA outcomes were compared across the four sites. When mean postoperative VA or crude proportions of patients with a visual outcome of <,0.67 were compared across sites, a much poorer outcome was seen in Barcelona. However, higher age, poorer general health status, lower preoperative VA and presence of ocular comorbidity were found to be significant risk factors associated with increased likelihood of poorer postoperative VA. The proportions of patients with these risk factors varied across sites. After controlling for the different distributions of these factors, no significant difference remained across the four sites regarding risk of a poor visual outcome. Once again the importance of controlling for case mix was demonstrated. In the fourth paper, we examined the postoperative VF-14 score as a measure of visual outcomes for cataract surgery in health care settings in four countries. Controlling for case mix was also necessary for this variable. After controlling for patient case mix, the odds for achieving an optimal visual function outcome were similar across the four sites. Age, gender and coexisting ocular pathology were important predictors of visual functional outcome. Despite what seemed to be an optimal surgical outcome, a third of patients still experienced visual disabilities in everyday life. A measure of the VF-14 might help to elucidate this issue, especially in any study evaluating the benefits of cataract surgery in a public health care context. [source] Plasma protein Z levels in healthy and high-risk newborn infantsACTA PAEDIATRICA, Issue 5 2004F Schettini Jr Aim: To evaluate plasma protein Z (PZ) levels in healthy and high-risk newborn infants. Methods: A longitudinal observational study was conducted. Inclusion criteria were: healthy term and pre-term newborns normal for gestational age and newborns belonging to one of the following groups: newborns small for gestational age (SGA), newborns affected by respiratory distress syndrome (RDS), newborns from mothers with pre-eclampsia. Newborns with sepsis, congenital malformation or haemorrhagic disorders were excluded. Plasma PZ levels, protein C (PC) concentration, PC activity and protein-induced vitamin K absence levels were measured. Results: 53 newborns were enrolled into the study. PZ and PC antigen levels varied significantly among analysed subgroups on day 1 (p < 0.01): lower levels of these inhibitors were found in RDS newborns (group C), newborns from mothers affected by pre-eclampsia (group D) and SGA newborns (group E) than in healthy term and preterm newborns (groups A and B). Conclusion: PZ deficiency occurs in newborns affected by severe RDS, in newborns from pre-eclamptic mothers and in SGA newborns, probably owing to activated coagulation in the first two conditions and to reduced PZ synthesis in the last condition. [source] | ||||||||||