Prevalence of Metabolically Healthy Obese and Metabolically Obese but Normal Weight in Adults Worldwide: A Meta-Analysis.

The objective of the present study was to summarize the prevalence and influencing factors of metabolically healthy obese (MHO) and metabolically obese but normal weight (MONW) among people ≥ 18 years old in the general population worldwide. We searched for studies of the prevalence of MHO and MONW published in English and Chinese up to October 2013. Pooled prevalence estimates were calculated by a random-effects model according to a Q test. The effects of gender, region, age, sample size, smoking, and alcohol consumption on MHO and MONW were analyzed. Differences between subgroups were assessed by chi-square test. Publication bias was estimated by Egger's test. Studies of MHO and MONW showed heterogeneity (I(2)=99.4% and I(2)=99.7%, respectively). The overall prevalence of MHO and MONW was 7.27% (95% CI 5.92-8.90%) and 19.98% (95% CI 16.54-23.94%), respectively. American populations had the highest MHO prevalence and European populations the highest MONW prevalence. Different patterns of MHO and MONW were observed in the subgroup analysis with respect to gender, age, sample size, smoking, alcohol consumption, and metabolically healthy criteria. The prevalence of both MHO and MONW were affected by gender, region, age, sample size, smoking, alcohol consumption, and metabolically healthy criteria, but studies showed high heterogeneity.