Obesity paradox on the survival of elderly patients with diabetes: an AHAP-based study.

Background and objectives: Overweight and obesity are among the important challenges in health issues and survival of elderly people. The current study aimed to evaluate the survival rate of elderly patients with diabetes, and its influencing factors, on the basis of body mass index (BMI).

Methods and materials: The design of the current study was based on the Amirkola Health and Aging Project (AHAP) cohort. The 5-year survival rate of elderly people with diabetes and the factors that influence the mortality rate by Cox regression model were analyzed.

Results: Out of 1616 elderly people who were evaluated in the current study, 501 (31%) had diabetes. The results showed that diabetes significantly increased the mortality rate (adjusted hazard ratio [HR] = 2.10; 95% confidence interval [CI]: 1.57-2.81; P  < 0.001). Furthermore, overweight (HR = 0.41; 95%CI: 0.24-0.75; P  = 0.002), obesity (HR = 0.30; 95% CI: 0.41-0.63; P = 0.002), history of diabetes (HR = 0.56; 95%CI: 0.34-0.93; P  = 0.024), moderate and high physical activity level (HR = 0.36; 95%CI: 0.13-0.99; P  = 0.049) decreased the risk of mortality and central obesity (HR = 1.76; 95% CI: 1.01-3.11; P = 0.049), fasting blood sugar ≥200 (HR = 2.46; 95% CI: 1.46-4.15; P  < 0.001), brain stroke, and neurological diseases (HR = 3.12; 95% CI: 1.78-5.49; P < 0.001) increased the risk of mortality.

Conclusion: Although overweight and obesity significantly improved the risk of mortality in elderly patients with diabetes, central obesity is still considered as an important risk factor.