Body mass index and risk of head and neck cancer by race: the Carolina Head and Neck Cancer Study
Menée aux Etats-Unis auprès de 1 289 cas et de 1 361 témoins, cette étude évalue l'association entre l'indice de masse corporelle, l'origine ethnique et le risque de cancer de la tête et du cou
Purpose : Most studies, primarily conducted in populations of European ancestry, reported increased risk of head and neck cancer (HNC) associated with leanness (body mass index (BMI) <18.5 kg/m2) and decreased for overweight or obesity (25.0-<30.0 and >30 kg/m2, respectively), compared to normal weight (18.5-<25.0 kg/m2). Methods : The Carolina Head and Neck Cancer Study is a population-based, racially diverse case-control study of 1,289 incident HNC cases (330 African-Americans) and 1,361 controls (261 African-Americans). Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated for associations between BMI one year pre-diagnosis and HNC risk stratified by race and adjusted for age, sex, smoking, alcohol, and education. Results : Multiplicative interaction between BMI and race was evident (pint=0.00007). Compared to normal weight, ORs for leanness were increased for African-Americans (OR=3.91, 95% CI 0.72-21.17) and whites (1.48, 0.60-3.65). For overweight and obesity, ORs were decreased in African-Americans (0.51, 0.32-0.83 and 0.47, 0.28-0.79, respectively), but not whites. The increased risk associated with leanness was greater for smokers than non-smokers (pint=0.02). Conclusions : These data, which require replication, suggest that leanness is associated with increased HNC risk among African-Americans to a greater extent than whites and overweight and obesity is associated with decreased HNC risk only among African-Americans.