Obesity as a Determinant of Staphylococcus aureus Colonization Among Inmates in Maximum-Security Prisons in New York State.

Obesity increases a person's susceptibility to a variety of infections, including Staphylococcus aureus infections, which is an important cause of morbidity in correctional settings. Using a cross-sectional design, we assessed the association between obesity and S. aureus colonization, a risk factor for subsequent infection, in New York State maximum-security prisons (2011-2013). Anterior nares and oropharyngeal cultures were collected. Structured interviews and medical records were used to collect demographic, behavioral, and medical data. Body mass index (BMI; weight (kg)/height (m(2))) was categorized as 18.5-24.9, 25-29.9, 30-34.9, or ≥35. The association between BMI and S. aureus colonization was assessed using log-binomial regression. Thirty-eight percent of 638 female inmates and 26% of 794 male inmates had a BMI of 30 or higher. More than 40% of inmates were colonized. Female inmates with a BMI of 25-29.9 (prevalence ratio (PR) = 1.37, 95% confidence interval (CI): 1.06, 1.76), 30-34.9 (PR = 1.52, 95% CI: 1.17, 1.98), or ≥35 (PR = 1.49, 95% CI: 1.13, 1.96) had a higher likelihood of colonization than did those with a BMI of 18.5-24.9 after we controlled for age, educational level, smoking status, diabetes status, and presence of human immunodeficiency virus. Colonization was higher among male inmates with a BMI of 30-34.9 (PR = 1.27, 95% CI: 1.01, 1.61). Our findings demonstrate an association between BMI and S. aureus colonization among female prisoners. Potential contributory biologic and behavioral factors should be explored.