The epidemic of depression with obesity.

I n this month's issue, Olvera and colleagues 1 provide important findings about the increasingly recognized link among depression, obesity, and metabolic syndrome. 2 Evaluating 1,768 Mexican American adults living on the United States/Mexico border from 2004 to 2010, they found that 30% had current depression, 14% had severe depression, 52% were obese, and 45% had metabolic syndrome. Depression was associated with female gender, low education, low high-density lipoprotein cholesterol, and increased waist circumference, while severe depression was associated with female gender, low education, and extreme obesity. The authors concluded that among Mexican Americans, obesity, female gender, and low education were risk factors for depression. To provide context, these findings can be compared with data from the National Health and Nutrition Examination Survey (NHANES) obtained during a comparable time period, 2005 to 2010. 2 As in Olvera and colleagues 1 study, obesity was defined as a body mass index (BMI) ≥ 30 mg/ kg 2 , BMI was determined from measured (as opposed to self-report) body weight and height, and depression was defined as exceeding a threshold of depressive symptoms over the past 2 weeks. In that data set, 7.2% had current depression and 34.6% were obese; 43% of adults with depression were obese; adults with depression were more likely to be obese than adults without depression; and the proportion of adults with obesity rose as the severity of depressive symptoms increased. Women with depression were more likely to be obese than women without depression in every age group, while this was true of men only in those ≥ 60 years. However, among Mexican American women and men, rates of obesity did not differ by depression status in the NHANES data. 2 The relationship between obesity and depression varied by race and ethnicity only among non-Hispanic white women. Thus, 46.6% of depressed Mexican American women were obese compared with 43.1% of nondepressed Mexican American women, while among non-Hispanic white women, 45% with depression were obese compared with 32% without depression. It is unknown why Olvera and colleagues' findings are inconsistent with NHANES, but they show that the links among depression, obesity, and metabolic derangement are just as relevant to Mexican American women as they are to other racial/ethnic groups. What do we know about the depression-obesity relationship? As found by Olvera and colleagues, 1 this relationship appears to be stronger in women than in men and with greater severity of …