Cutaneous Melanoma and Obesity in the Agricultural Health Study

Purpose: To describe the risk of cutaneous melanoma in the Agricultural Health Study (AHS), a cohort of pesticide applicators and their spouses, according to baseline characteristics related to obesity along with sun exposure and sun sensitivity. Methods: The AHS cohort was enrolled in Iowa and North Carolina during 1993-1997 and followed up through 2003 for cancer incidence. We identified 315 cases of cutaneous melanoma, which reduced to 168 incident cases among subjects reporting height, weight, sun sensitivity, and sun exposure information (on the spouse questionnaire or take-home applicator questionnaire; N = 44,086). Unconditional multiple logistic regression models were used to obtain adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs). Results: The results were consistent with those of prior studies of melanoma that indicate an association with measures of sun sensitivity. The highest category of body surface area (BSA; OR = 2.6; 95% CI, 1.5-4.4) and body mass index (BMI; OR = 2.5; 95% CI, 1.5-4.3) at age 20 were significantly associated with melanoma. There was some evidence for an association with BSA, but not BMI, at enrollment. Conclusions: Obesity was associated with an increased risk of melanoma, indicating strategies to control obesity may result in risk reduction for melanoma.