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1.
Fereshteh Asgari Akbar Biglarian Behjat Seifi Andisheh Bakhshi Hamid Heidarian Miri Enayatollah Bakhshi 《Annals of epidemiology》2013,23(9):534-538
PurposeThe last study that had a representative sample of the Iranian population and examined the association between sociodemographic and lifestyle factors with obesity used data from the 1999 to 2000 National Health Survey in Iran. Concern about the increased prevalence of obesity has heightened interest in the association between varieties of these factors with obesity among Iranian households.MethodsData (20,917 adults) were taken from the 2009 STEPwise approach to Surveillance survey in Iran that was conducted under the supervision of World Health Organization. Using quadratic inference function, we evaluated the relation of age, sex, physical activity, serving of fruit and vegetable, employment status, smoking, and place of residence with obesity.ResultsUsing 20–30 years as the reference group, the obesity odds ratios (ORs) were 2.48, 3.79, 3.52, and 3.15 for ages 30–40, 40–50, 50–60, and 60+ years, respectively. Obesity OR for female was 2.63, compared with male. Obesity ORs for smokers and ex-smokers were 0.64 and 1.18, respectively, compared with nonsmokers. Among Iranian adult, obesity ORs for the moderate and vigorous physical activity were 0.99 and 0.90, respectively, compared with low level. The estimated odds of obesity were 46% higher for rural adults. Obesity ORs for public and private employed were 0.79 and 0.76, respectively, compared with unemployed.ConclusionsOur results may provide better insights of the factors associated with obesity and can be used as a basis to reinforce health programs to prevent obesity in Iran. 相似文献
2.
Jon J. Ford Matt C. Richards Luke D. Surkitt Alexander Y.P. Chan Sarah L. Slater Nicholas F. Taylor Andrew J. Hahne 《Archives of physical medicine and rehabilitation》2018,99(12):2504-2512.e12
Objective
To identify predictors for back pain, leg pain, and activity limitation in patients with early persistent low back disorders (LBDs).Design
Prospective inception cohort study.Setting
Primary care private physiotherapy clinics in Melbourne, Australia.Participants
Individuals (N=300) aged 18-65 years with low back and/or referred leg pain of ≥6 weeks and ≤6 months duration.Interventions
Not applicable.Main Outcome Measures
Numeric rating scales for back pain and leg pain as well as the Oswestry Disability Scale.Results
Prognostic factors included sociodemographics, treatment related factors, subjective/physical examination, subgrouping factors, and standardized questionnaires. Univariate analysis followed by generalized estimating equations were used to develop a multivariate prognostic model for back pain, leg pain, and activity limitation. Fifty-eight prognostic factors progressed to the multivariate stage where 15 showed significant (P<.05) associations with at least 1 of the 3 outcomes. There were 5 indicators of positive outcome (2 types of LBD subgroups, paresthesia below waist, walking as an easing factor, and low transversus abdominis tone) and 10 indicators of negative outcome (both parents born overseas, deep leg symptoms, longer sick leave duration, high multifidus tone, clinically determined inflammation, higher back and leg pain severity, lower lifting capacity, lower work capacity, and higher pain drawing percentage coverage). The preliminary model identifying predictors of LBDs explained up to 37% of the variance in outcome.Conclusions
This study evaluated a comprehensive range of prognostic factors reflective of both the biomedical and psychosocial domains of LBDs. The preliminary multivariate model requires further validation before being considered for clinical use. 相似文献3.
Person‐related determinants of TV viewing and computer time in a cohort of young Dutch adults: Who sits the most? 下载免费PDF全文
L. Uijtdewilligen A. S. Singh M. J. M. Chinapaw J. W. R. Twisk W. van Mechelen 《Scandinavian journal of medicine & science in sports》2015,25(5):716-723
We aimed to assess the associations of person‐related factors with leisure time television (TV) viewing and computer time among young adults. We analyzed self‐reported TV viewing (h/week) and leisure computer time (h/week) from 475 Dutch young adults (47% male) who had participated in the Amsterdam Growth and Health Longitudinal Study at the age of 32 and 36 years. Sociodemographic factors (i.e., marital and employment status), physical factors (i.e., skin folds, aerobic fitness, neuromotor fitness, back problems), psychological factors (i.e., problem‐ and emotion‐focused coping, personality), lifestyle (i.e., alcohol consumption, smoking, energy intake, physical activity), and self‐rated health (i.e., general health status, mild health complaints) were assessed. Univariable and multivariable generalized estimating equations were performed. Male gender, higher sum of skin folds, lower values of aerobic fitness, higher rigidity, higher self‐sufficiency/recalcitrance, and smoking were positively associated with TV time. Male gender, higher sum of skin folds, higher scores on self‐esteem, low energy intake, and a not so good general health status were significantly associated with higher computer time. Determinants of TV viewing and computer time were not identical, suggesting that both behaviors (a) have different at‐risk populations and (b) should be targeted differently. 相似文献
4.
Roel S. Driessen Wijnand J. Stuijfzand Pieter G. Raijmakers Ibrahim Danad James K. Min Jonathon A. Leipsic Amir Ahmadi Jagat Narula Peter M. van de Ven Marc C. Huisman Adriaan A. Lammertsma Albert C. van Rossum Niels van Royen Paul Knaapen 《Journal of the American College of Cardiology》2018,71(5):499-509
Background
Atherosclerotic plaque characteristics may affect downstream myocardial perfusion, as well as coronary lesion severity.Objectives
This study sought to evaluate the association between quantitative plaque burden and plaque morphology obtained using coronary computed tomography angiography (CTA) and quantitative myocardial perfusion obtained using [15O]H2O positron emission tomography (PET), as well as fractional flow reserve (FFR) derived invasively.Methods
Two hundred eight patients (63% men; age 58 ± 8.7 years) with suspected coronary artery disease were prospectively included. All patients underwent 256-slice coronary CTA, [15O]H2O PET, and invasive FFR measurements. Coronary CTA-derived plaque burden and morphology were assessed using commercially available software and compared with PET perfusion and FFR.Results
Atherosclerotic plaques were present in 179 patients (86%) and 415 of 610 (68%) evaluable coronary arteries. On a per-vessel basis, traditional coronary plaque burden indexes, such as plaque length and volume, minimal lumen area, and stenosis percentage, were significantly associated with impaired hyperemic myocardial blood flow (MBF) and FFR. In addition, morphological features, such as partially calcified plaques, positive remodeling (PR), and low attenuation plaque, displayed a negative impact on hyperemic MBF and FFR. Multivariable analysis revealed that the morphological feature of PR was independently related to impaired hyperemic MBF as well as an unfavorable FFR (p = 0.004 and p = 0.007, respectively), next to stenosis percentage (p = 0.001 and p < 0.001, respectively) and noncalcified plaque volume (p < 0.001 and p = 0.010, respectively).Conclusions
PR and noncalcified plaque volume are associated with detrimental downstream hyperemic myocardial perfusion and FFR, independent of lesion severity. 相似文献5.
Ann M. Vuong Kimberly Yolton Kendra L. Poston Changchun Xie Glenys M. Webster Andreas Sjödin Joseph M. Braun Kim N. Dietrich Bruce P. Lanphear Aimin Chen 《International journal of hygiene and environmental health》2018,221(1):87-94
Prenatal exposure to polybrominated diphenyl ethers (PBDEs) have been reported to impair executive function in children, but little is known whether childhood PBDE exposures play a role. Using the Health Outcomes and Measures of the Environment (HOME) Study, a prospective birth cohort in the greater Cincinnati area, we investigated the association between repeated measures of PBDEs during childhood and executive function at 8 years in 208 children and whether effect modification by child sex was present. We used child serum collected at 1, 2, 3, 5, and 8 years to measure PBDEs. The Behavior Rating Inventory of Executive Function was completed by parents to assess executive function at 8 years. We used multiple informant models to examine childhood PBDEs during several exposure windows. Null associations were observed between early childhood PBDEs and executive function. However, we observed significant adverse associations between a 10-fold increase in concurrent concentrations of BDE-28 (β = 4.6, 95% CI 0.5, 8.7) and BDE-153 (β = 4.8, 95% CI 0.8, 8.8) with behavioral regulation. In addition, PBDEs at 8 years were significantly associated with poorer emotional and impulse control. No associations were noted between childhood PBDEs and metacognition or global executive function. However, child sex significantly modified the associations, with significantly poorer executive function among males with higher concurrent BDE-153, and null associations in females. Our study findings suggest that concurrent PBDE exposures during childhood may be associated with poorer executive function, specifically behavior regulation. Males may also be more sensitive to adverse associations of concurrent PBDEs on executive function. 相似文献
6.
7.
The sandwich variance estimator of generalized estimating equations (GEE) may not perform well when the number of independent clusters is small. This could jeopardize the validity of the robust Wald test by causing inflated type I error and lower coverage probability of the corresponding confidence interval than the nominal level. Here, we investigate the small-sample performance of the robust score test for correlated data and propose several modifications to improve the performance. In a simulation study, we compare the robust score test to the robust Wald test for correlated Bernoulli and Poisson data, respectively. It is confirmed that the robust Wald test is too liberal whereas the robust score test is too conservative for small samples. To explain this puzzling operating difference between the two tests, we consider their applications to two special cases, one-sample and two-sample comparisons, thus motivating some modifications to the robust score test. A modification based on a simple adjustment to the usual robust score statistic by a factor of J/(J - 1) (where J is the number of clusters) reduces the conservativeness of the generalized score test. Simulation studies mimicking group-randomized clinical trials with binary and count responses indicated that it may improve the small-sample performance over that of the generalized score and Wald tests with test size closer to the nominal level. Finally, we demonstrate the utility of our proposal by applying it to a group-randomized clinical trial, trying alternative cafeteria options in schools (TACOS). 相似文献
8.
Predicting final infarct size using acute and subacute multiparametric MRI measurements in patients with ischemic stroke 总被引:1,自引:0,他引:1
Lu M Mitsias PD Ewing JR Soltanian-Zadeh H Bagher-Ebadian H Zhao Q Oja-Tebbe N Patel SC Chopp M 《Journal of magnetic resonance imaging : JMRI》2005,21(5):495-502
PURPOSE: To identify early MRI characteristics of ischemic stroke that predict final infarct size three months poststroke. MATERIALS AND METHODS: Multiparametric MRI (multispin echo T2-weighted [T2W] imaging, T1-weighted [T1W] imaging, and diffusion-weighted imaging [DWI]) was performed acutely (<24 hours), subacutely (three to five days), and at three months. MRI was processed using maps of apparent diffusion coefficient (ADC), T2, and a self-organizing data analysis (ISODATA) technique. Analyses began with testing for individual MRI parameter effects, followed by multivariable modeling with assessment of predictive ability (R(2)) on final infarct size. RESULTS: A total of 45 patients were studied, 15 of whom were treated with tissue plasminogen activator (tPA) before acute MRI. The acute DWI and DWI-ISODATA mismatch lesion size, and the interactions of ADC, T2, and T2W imaging lesion with tPA remained in the final multivariable model (R(2) = 70%). A large acute DWI lesion or DWI < ISODATA lesion independently predicted increase in the final infract size, with predictive ability 68%. Predictive ability increased (R(2) = 83%) when subacute MRI parameters were included along with acute DWI, DWI-ISODATA mismatch, and acute T2W image lesion size by tPA treatment interaction. Subacute DWI > acute DWI lesion size predicted an increased final infarct size (P < 0.01). CONCLUSION: Acute-phase DWI and DWI-ISODATA mismatch strongly predict the final infarct size. An acute-to-subacute DWI lesion size change further increases the predictive ability of the model. 相似文献
9.
Tsalikian E Mauras N Beck RW Tamborlane WV Janz KF Chase HP Wysocki T Weinzimer SA Buckingham BA Kollman C Xing D Ruedy KJ;Diabetes Research In Children Network Direcnet Study Group 《The Journal of pediatrics》2005,147(4):528-534
OBJECTIVE: To examine the effect of exercise on overnight hypoglycemia in children with type 1 diabetes mellitus (T1DM). STUDY DESIGN: At 5 clinical sites, 50 subjects with T1DM (age 11 to 17 years) were studied in a clinical research center on 2 separate days. One day included an afternoon exercise session on a treadmill. On both days, frequently sampled blood glucose levels were measured at the DirecNet central laboratory. Insulin doses were similar on both days. RESULTS: During exercise, plasma glucose levels fell in almost all subjects; 11 (22%) developed hypoglycemia. Mean glucose level from 10 pm to 6 am was lower on the exercise day than on the sedentary day (131 vs 154 mg/dL; P=.003). Hypoglycemia developed overnight more often on the exercise nights than on the sedentary nights (P=.009), occurring on the exercise night only in 13 (26%), on the sedentary night only in 3 (6%), on both nights in 11 (22%), and on neither night in 23 (46%). Hypoglycemia was unusual on the sedentary night if the pre-bedtime snack glucose level was>130 mg/dL. CONCLUSIONS: These findings indicate that overnight hypoglycemia after exercise is common in children with T1DM and support the importance of modifying diabetes management after afternoon exercise to reduce the risk of hypoglycemia. 相似文献
10.
We used simulation to compare accuracy of estimation and confidence interval coverage of several methods for analysing binary outcomes from cluster randomized trials. The following methods were used to estimate the population-averaged intervention effect on the log-odds scale: marginal logistic regression models using generalized estimating equations with information sandwich estimates of standard error (GEE); unweighted cluster-level mean difference (CL/U); weighted cluster-level mean difference (CL/W) and cluster-level random effects linear regression (CL/RE). Methods were compared across trials simulated with different numbers of clusters per trial arm, numbers of subjects per cluster, intraclass correlation coefficients (rho), and intervention versus control arm proportions. Two thousand data sets were generated for each combination of design parameter values. The results showed that the GEE method has generally acceptable properties, including close to nominal levels of confidence interval coverage, when a simple adjustment is made for data with relatively few clusters. CL/U and CL/W have good properties for trials where the number of subjects per cluster is sufficiently large and rho is sufficiently small. CL/RE also has good properties in this situation provided a t-distribution multiplier is used for confidence interval calculation in studies with small numbers of clusters. For studies where the number of subjects per cluster is small and rho is large all cluster-level methods may perform poorly for studies with between 10 and 50 clusters per trial arm. 相似文献