Overweight, obesity and risk of all-cause and cardiovascular mortality in patients with type 2 diabetes mellitus: a dose-response meta-analysis of prospective cohort studies

• Published in: European journal of epidemiology 2015-01, Vol.30 (1), p.35-45
• Main Authors: Liu, Xue-ming, Liu, Yu-jian, Zhan, Jian, He, Qi-qiang
• Format: Article
• Language: English
• Subjects: Body Mass Index; Body Weight; Cardiology; Cardiovascular Diseases - complications; Cardiovascular Diseases - mortality; Diabetes; Diabetes Mellitus, Type 2 - complications; Diabetes Mellitus, Type 2 - mortality; Epidemiology; Female; Health risks; Humans; Infectious Diseases; Male; Medicine; Medicine & Public Health; META-ANALYSIS; Mortality; Obesity; Obesity - complications; Obesity - mortality; Oncology; Overweight - complications; Overweight - mortality; Prospective Studies; Public Health; Risk; Risk factors; Risk Reduction Behavior
• ISSN: 0393-2990; 1573-7284; 1573-7284
• DOI: 10.1007/s10654-014-9973-5

Overweight and obese individuals with type 2 diabetes are recommended to lose weight, but the associations between excess body weight and all-cause and cardiovascular mortality in patients with type 2 diabetes remain controversial. Therefore, we performed a doseresponse meta-analysis to investigate this association. We searched PubMed and Embase through 19th October 2014 and examined the references of retrieved articles to identify relevant prospective cohort studies. A random-effect model was used to calculate the summary risk estimates. Nine studies including 13 cohorts with 161,984 participants were identified. The relative risks (RRs) of all-cause mortality in overweight and obese patients with type 2 diabetes were 0.81 (95 % confidence interval (CI) 0.74-0.90) and 0.72 (95 % CI 0.63-0.81) respectively, compared with the normal or non-overweight patients. Furthermore, a 5 kg/m 2 increase in body mass index was associated with a significantly reduced risk of all-cause mortality by 5 % (RR 0.95, 95 % CI 0.93-0.97). However, no significant association was found between obese and/or overweight and the risk of cardiovascular mortality in type 2 diabetic patients (RR 0.89; 95 % CI 0.66-1.20 for overweight and RR 0.77; 95 % CI 0.54-1.10 for obesity, respectively). The findings from the present meta-analysis indicate that excess body weight may be a protective factor for all-cause mortality among patients with type 2 diabetes.