title: Obesity is associated with lower mortality risk in elderly diabetic subjects: the Casale Monferrato study.
abstract: The relationship between obesity and mortality in people with type 2 diabetes has not been definitely assessed. We have examined this issue in a well-characterized population-based cohort of Mediterranean diabetic people. Standardized anthropometric data from the population-based Casale Monferrato Study have been prospectively analyzed. The cohort included 1,475 people (62.6% aged ≥65 years) who had been recruited in 1991 and followed-up to December 31, 2006. Cox proportional hazards modeling was employed to estimate the independent associations between all-cause and cardiovascular mortality and BMI. Out of 1,475 people, 972 deaths occurred during a 15-year follow-up. Cox regression analyses showed that with respect to BMI <24.2 kg/m(2), values of 30.0 kg/m(2) and over were associated with lower all-cause and cardiovascular mortality risk (HR = 0.68, 95% CI 0.56-0.85, P for trend = 0.001; HR = 0.59, 0.44-0.80, P for trend = 0.002), independently of classical and new risk factors. As interaction between age and BMI was significant, we performed a stratified analysis by age, providing evidence that our finding was entirely due to a significant protective effect of BMI of 30.0 kg/m(2) and over in the elderly (all-cause mortality HR = 0.75, 95% CI 0.58-0.96; cardiovascular mortality HR = 0.67, 95% CI 0.45-0.95). In contrast, obesity was not significantly associated with mortality risk in diabetic subjects aged <65 years. Results were confirmed even excluding from the analysis individuals who died within 2 years of follow-up, smokers and those with CHD. In Mediterranean diabetic people aged ≥65 years, obesity is significantly associated with lower 15-year mortality risk. In contrast, it was not significantly associated with mortality risk in diabetic subjects aged <65 years. As more than two-thirds of people with type 2 diabetes are elderly, our findings, if confirmed, could have clinical implications.
authors: Department of Internal Medicine, University of Turin, Corso Dogliotti 14, I-10126, Turin, Italy.
authors: Massimo
authors: M
authors: Perotto
authors: Francesco
authors: F
authors: Panero
authors: Gabriella
authors: G
authors: Gruden
authors: Paolo
authors: P
authors: Fornengo
authors: Bartolomeo
authors: B
authors: Lorenzati
authors: Federica
authors: F
authors: Barutta
authors: Giuseppe
authors: G
authors: Ghezzo
authors: Cristina
authors: C
authors: Amione
authors: Paolo
authors: P
authors: Cavallo-Perin
authors: Graziella
authors: G
authors: Bruno
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000209:etiology / Q000401:mortality*; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000401:mortality / Q000503:physiopathology; D003925:Diabetic Angiopathies / Q000453:epidemiology / Q000209:etiology / Q000401:mortality*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D009765:Obesity / Q000150:complications* / Q000401:mortality / Q000503:physiopathology; D016016:Proportional Hazards Models; D012307:Risk Factors