A prospective study of body mass index, hypertension, and smoking and the risk of renal cell carcinoma (United States).

OBJECTIVE: We prospectively investigated the independent association of hypertension, thiazide use, body mass index, weight change, and smoking with the risk of renal cell carcinoma among men and women using biennial mailed questionnaires.

METHODS: The study population included 118,191 women participating in the Nurses' Health Study and 48,953 men participating in the Health Professionals Follow-up Study.

RESULTS: During 24 years of follow-up for women and 12 years for men, 155 and 110 incident cases of renal cell carcinoma were confirmed, respectively. In multivariate models including age, body mass index (BMI), smoking and hypertension, higher BMI was confirmed as a risk factor for women and smoking as a risk factor for men and women. After adjusting for age, updated BMI and smoking, an updated diagnosis of hypertension was associated with renal cell carcinoma (RCC); the relative risk (RR) was 1.9 (95% CI 1.4-2.7) for women and 1.8 (95% CI 1.2-2.7) for men. Based on limited data regarding the use of thiazide diuretics, we did not observe a risk associated with their use, independent of the diagnosis of hypertension.

CONCLUSIONS: Diagnosis of hypertension, higher BMI, and increasing pack-years of smoking appear to independently increase the risk of renal cell carcinoma.