Body mass index and risk of head and neck cancer by race: the Carolina Head and Neck Cancer Epidemiology Study.

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/m(2)) and decreased for overweight or obesity (25.0 to <30.0 and >30 kg/m(2), respectively), compared with normal weight (18.5 to <25.0 kg/m(2)).

METHODS

The Carolina Head and Neck Cancer Epidemiology Study is a population-based, racially diverse case-control study of 1289 incident HNC cases (330 African Americans) and 1361 controls (261 African Americans). Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated for associations between BMI 1 year prediagnosis 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 = .00007). Compared with normal weight, ORs for leanness were increased for African Americans (OR, 3.91; 95% CI, 0.72-21.17) and whites (OR, 1.48; 95% CI, 0.60-3.65). For overweight and obesity, ORs were decreased in African Americans (OR, 0.51; 95% CI, 0.32-0.83 and OR, 0.47; 95% CI, 0.28-0.79, respectively) but in not whites. The increased risk associated with leanness was greater for smokers than nonsmokers (Pint = .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.