Background: Body weight reduction (BWR) of at least 3% in obese Japanese individuals through lifestyle interventions has improved the risk factors for cardiovascular disease (CVD). We aimed to assess the relation between body weight change (BWC) and CVD risk change and to identify lifestyle improvement related to BWR in obese Japanese individuals. Methods: Subjects were 2579 health checkup examinees without medicated diabetes, hypertension or dyslipidemia, and a body mass index ≥25 kg/m2 who completed lifestyle questionnaires in 2008 and 2012. The 4-year changes in fasting plasma glucose (FPG), glycated hemoglobin (HbA1c), lipids, and blood pressure (BP) levels were compared across the five groups based on the 4-year BWC, and presented as <-5%, -5% to -3%, -3% to -1%, -1% to 1%, and ≥1%. Multivariable logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (CI) for lifestyle improvement related to BWR. Results: Comparing the groups to the reference group (BWC ranging from -1% to +1%), we observed that FPG and HbA1c levels were lower in women in the <-5% group; BP levels were also lower in the <-5% group; triglyceride levels had improved in the <-3% group, and low-density lipoprotein cholesterol levels in the <-5% group; high-density lipoprotein cholesterol levels had improved in men in the <-5% group. In men, the adjusted OR (95% CI) for BWR related to lifestyle improvement pertaining to "over 30 min exercise" was 2.6 (2.0-3.6). In women, the adjusted ORs for BWR related to "walking or physical activity," "drinking alcohol," and "drinking more than a glass of sake" were 1.7 (1.1-2.7), 1.9 (1.1-3.5), and 1.8 (1.1-3.0), respectively. Conclusions: A 5% BWR improved FPG and HbA1c levels in obese women, and BP and lipid levels in obese men. Improvements in exercise and alcohol consumption habits were associated with BWR in this population.
Keywords: body weight change; metabolic syndrome; obesity; physical activity.