Do overweight students have lower academic performance than their classmates? A pilot cross sectional study in a middle school in Tehran.

BACKGROUND: Recently the special attention is given to psychological aspects of childhood obesity in overweight and obese children. The present pilot study aims to investigate the association of obesity and lipid profile with school performance among Iranian students. METHODS: 69 middle school male students between the ages of 12 to 14 in 2009-2010 were studied. BMI was considered as the obesity index. The students' Grade Point Average (GPA) along with their scores in math, geometry, calculus, English and absent rate were obtained as academic performance. Serum lipid profile was also assessed by a uniform method. RESULTS: The GPA score, math and geometry scores were lower in overweight students in comparison with control group. The study of serum lipid profile indices showed no significant statistical association between serum lipid profile and school performance. CONCLUSIONS: Our results support previous findings pointing out the negative effects of obesity on students' school performance.

Meta-analysis of genetic polymorphisms and ophthalmologic disease risk in Asian populations: a case of DNA repair XRCC1 gene.

This study aimed to assess a meta-analysis of the association of XRCC1 polymorphisms with the risk of various ophthalmologic diseases in Asian population. This meta-analysis was performed by critically reviewing reveals 38 studies involving 1373 cases and 1745 controls. Among all the eligible studies, one focused on Arg194Trp polymorphism, nine described the Arg399Gln and no article investigated on Arg280His. There was a large between-study heterogeneity in ORs of individual studies of the dominant model (chi2 = 74.18, I2 = 58.9%, p = 0.013) and the additive (chi2 = 56.18, I2 = 41.4%, p = 0.091) models, but a moderate heterogeneity in the recessive model (chi2 = 72.27, I2 = 78.8%, p = 0.000) was observed. So, we pooled the results using the random-effect analysis and found that Arg399Gln has a weak relation with ophthalmologic disease in the recessive (OR = 0.96, 95% CI: 0.64-1.44), the dominant (OR = 1.05, 95% CI: 0.82-1.33) and the additive (OR = 1.15, 95% CI: 0.77-1.70) and models. The present meta-analysis correspondingly shows that comprising diverse population is very important since susceptibility loci might vary indifferent ethnic groups. To ratify our findings, widespread studies with enlarged sample size and various populations are essential to explain the role of all polymorphism of XRCC1 genes in the pathogenesis of ophthalmologic diseases. Finally, our meta-analysis showed Arg399Gln variant was not associated with increased ophthalmologic diseases risk via dominant and recessive modes among Asian population.

Deoxyribonucleic acid repair gene X-ray repair cross-complementing group 1 polymorphisms and non-carcinogenic disease risk in different populations: A meta-analysis.

PURPOSE: This study aims to assess a meta-analysis of the association of X-ray repair cross-complementing group 1 (XRCC1) polymorphisms with the risk of various non-carcinogenic diseases in different population. MATERIALS AND METHODS: This meta-analysis was performed by critically reviewing reveals 38 studies involving 10043 cases and 11037 controls. Among all the eligible studies, 14 focused on Arg194Trp polymorphism, 33 described the Arg399Gln and three articles investigated on Arg280His. Populations were divided into three different ethnic subgroups include Caucasians, Asians and other (Turkish and Iranian). RESULTS: Pooled results showed no correlation between Arg194Trp and non-carcinogenic disease. There was only weak relation in the recessive (odds ratio [OR] =1.11, 95% confidence interval [CI]: 0.86-1.44) model in Asian population and dominant (OR = 1.04, 95% CI: 0.66-1.63) model of other populations. In Arg399Gln polymorphism, there was no relation with diseases of interest generally. In the pooled analysis, there were weak relation in the dominant (OR = 1.08, 95% CI: 0.86-1.35) model of Asian population and quite well-correlation with recessive (OR = 1.49, 95% CI: 1.19-1.88), dominant (OR = 1.23, 95% CI: 0.94-1.62), and additive (OR = 1.23, 95% CI: 0.94-1.62) models of other subgroup. For Arg280His, there was a weak relation only in the dominant model (OR = 1.06, 95% CI: 0.74-1.51). CONCLUSION: The present meta-analysis correspondingly shows that Arg399Gln variant to be associated with increased non-carcinogenic diseases risk through dominant and recessive modes among Iranian and Turkish population. It also suggests a trend of dominant and recessive effect of Arg280His variant in all population and its possible protective effect on non-carcinogenic diseases.

Potentially preventable incidence of diabetes due to risk factor modification.

BACKGROUND: Increasing diabetes incidence demands investigation of risk factors, prioritization and designing modification interventions. We calculated the potential modifiable incidence of diabetes due to reduction in risk factors. METHODS: We used counterfactual analysis model to estimate avoidable burden of incident diabetes related to each risk factor. The potential impact fraction (PIF) index calculated utilizing the data of current prevalence, magnitude of impact and counterfactual status of risk factors. We considered the levels of evidence while giving higher priority to domestic data. RESULTS: The estimated PIF regarding minimum feasible risk for the impaired fasting glucose (IFG), impaired glucose tolerance (IGT), combined IFG/IGT, low HDL, high triglyceride, high total cholesterol, hypertension, general obesity, central obesity and physical inactivity were 0.13, 0.10, 0.18, 0.01, 0.12, 0.03, 0.13, 0.03, 0.02 and 0.10, respectively. CONCLUSION: While the combined risk factors of IFG and IGT should be noticed as the most important potential factor in prevention of diabetes and reducing its incidence burden, among the other risk factors, modification of hypertension, high triglyceride, and physical inactivity could have more impact.