Associations of obesity and physical activity with cognition in people aged 50 and above in Shanghai / 中华流行病学杂志

Objective: To investigate the associations of obesity and physical activity with cognition in the elderly. Methods: A cross-sectional survey was conducted from October 2009 to June 2010 among people aged ≥50 years selected through multistage random cluster sampling in Shanghai. The subjects' body weight, body height, waist circumference and hip circumference were measured to calculate body mass index (BMI) and waist-hip ratio (WHR), and the data on self-reported physical activity level were collected through questionnaire survey. A comprehensive battery of cognitive tests was conducted to assess subjects' cognitive functions, including verbal recall, forward digit span (FDS), backward digit span (BDS), and verbal fluency (VF). General linear model was used to examine the associations of BMI, WHR and physical activity with cognition. Results: A total of 7 913 participants were included, with a median age of 60 years. Age, sex, education level, income level, BMI, WHR and physical activity level were significantly associated with cognitive scores in univariate analysis. After adjusted for age, sex, education level and income level, BMI was no longer significantly associated with cognitive scores in all cognitive functions (all P>0.01). WHR was significantly associated with VF score (P<0.01). Abdominally obese participants had lower VF score than non-abdominally obese participants (P<0.01). Physical activity level was significantly associated with all cognitive functions (P<0.01). Compared with participants with moderate physical activity level, participants with low physical activity level had lower scores in all cognitive functions (P<0.01). Conclusion: Abdominal obesity and low physical activity level were negatively associated with cognition level in the elderly, suggesting that waist circumference control and physical activity might help maintain cognition in the elderly.

Effect of health literacy and exercise-focused interventions on glycemic control in patients with type 2 diabetes in China / 中华流行病学杂志

Objective: To evaluate the effect of health literacy and exercise-focused interventions on glycemic control in patients with type 2 diabetes (T2DM) in China. Methods: In this cluster randomized controlled trial, a total of 799 T2DM patients with most recent hemoglobin A1c (HbA1c) ≥ 7.5% (or fasting plasma glucose level ≥10 mmol/L) were recruited from 8 communities in Minhang and Changning districts of Shanghai, and randomized into a health literacy intervention group, an exercise intervention group, a comprehensive intervention group and a control group. After baseline survey and examination, a one-year intervention and 3 times (at 3(rd), 6(th), and 12(th) month) follow-up surveys were conducted. Results: The follow-up rates for all the subjects were 99.4%, 98.4% and 95.2%, respectively, at 3(rd), 6(th) and 12(th) month. Patients in intervention groups were more likely to achieve a goal HbA1c level (HbA1c <7.0%) than those in control group, with the highest glycemic control rate (25.3%) observed in comprehensive intervention group at 3(rd) month and then in exercise intervention group (25.3% and 34.6%) respectively, at 6(th) month and 12(th) month. The average levels of HbA1c in three intervention groups were lower at each follow-up time point than those at baseline survey. However, the decreases in HbA1c were obvious only at 6(th) month (P<0.001), with ls-mean (95%CI) of -0.48% (-0.71%, -0.25%), -0.33% (-0.55%, -0.11%) and -0.70% (-0.92%, -0.48%), respectively, in comprehensive, health literacy and exercise intervention groups, but it increased slightly by 0.03% (-0.19%, 0.25%) in control group. Compared with control group, the interventions were significantly associated with the decrease of HbA1c level, with the most improvement observed in comprehensive group (β=-0.47, 95% CI: -0.73, -0.20) at 3(rd) month, and in exercise intervention group at 6(th) month (β=-0.73, 95%CI: -0.98, -0.47) and at 12(th) month (β=-0.75, 95%CI: -1.05, -0.45) of follow-up. Stratified analyses showed that patients with lower health literacy level could benefit from any intervention, while those with higher numeracy skill benefited more from exercise intervention. Conclusion: Both health literacy and exercise-focused interventions may decrease HbA1c level in patients with T2DM, which would be helpful in reducing the risks of complications and deaths in diabetes patients.