Implementation of permutation testing to determine clustering of social and behavioral risk factors for coronary heart disease, National Health and Nutrition Examination Survey 2001-2004.

PURPOSE

To determine whether social and behavioral risk factors for coronary heart disease, including education, physical activity, fruit/vegetable intake, and smoking, cluster (i.e., co-occur more than expected as the result of chance) in U.S. adults.

METHODS

The study included 4305 male and 4673 female subjects aged ≥20 years from the National Health and Nutrition Examination Survey. Risk factors included: ≤high school diploma/general educational development certificate; <150 minutes of moderate/vigorous physical activity per week; <3 or <2 servings of vegetables and fruit, respectively, per day; and smoking cigarettes. Indicator variables were summed into a sociobehavioral risk index (SRI, range 0 [no risk factors] to 4 [all risk factors]). Ratios of observed-to-expected prevalence (under the assumption of independence) of the SRI were assessed. Statistical significance was evaluated by the use of randomly permuted average observed-to-expected SRI ratios and 95% confidence intervals (95% CIs).

RESULTS

In male subjects, the ratio of observed-to-expected prevalence of SRI = 0 was 1.70 (permuted ratio = 1.00; 95% CI: 0.92-1.08), and SRI = 4 was 2.10 (permuted ratio = 1.00, 95% CI: 0.86-1.14), demonstrating significant clustering. In females, the ratio of observed-to-expected prevalence of SRI = 0 was 1.67 (permuted ratio = 1.00, 95% CI: 0.92-1.08), and SRI = 4 was 1.86 (permuted ratio = 1.00, 95% CI: 0.85-1.15).

CONCLUSIONS

Social and behavioral risk factors for coronary heart disease cluster in this sample of U.S. adults.