Cumulative social risk and type 2 diabetes in US adults: The National Health and Nutrition Examination Survey (NHANES) 1999-2006.

Background: The cumulative effects of adverse social factors on the diabetes risk remains to be clarified.

Design: Cross-sectional analysis of the US National Health and Nutrition Examination Survey (NHANES) 1999-2006.

Methods: We included 10,276 adults aged ≥20 years. Diabetes mellitus was defined by physician diagnosis or fasting plasma glucose (≥126 mg/dl) or glycated hemoglobin (≥6.5%). Social risk factors (low family income, low education level, minority racial/ethnic group status, and single-living status) and health-related behaviors (physical activity and dietary intake) were self-reported. Social risk factors were combined in a cumulative social risk index (range 0 to ≥3) and logistic regression used to assess the association of cumulative social risk and diabetes, taking into account complex survey design and sampling weights.

Results: Of 10,276 participants, 1515 (weighted proportion - 10%) had diabetes, 3295 (32.3%) and 1830 (9.0%) were exposed to ≥1 adverse social risk factor and ≥3 social risk factors, respectively. Diabetes was associated with increasing cumulative social risk in a graded manner (p for trend <0.001). Compared with a cumulative social risk score of 0, the age- and sex-adjusted diabetes odds for a cumulative social risk score of ≥3 was 2.84 (95% confidence interval: 2.23-3.62), and 2.72 (95% confidence interval: 2.05-3.60) after further adjustment for family history of diabetes, body mass index, smoking, dietary intake and leisure time physical activity. Health behaviors and adiposity only partially influenced the cumulative social risk and diabetes relationship.

Conclusions: Simultaneous exposure to several adverse social risk factors significantly influences the odds of diabetes. Better prevention and control of diabetes needs accounting for all aspects of social disadvantage.