History of diabetes and risk of head and neck cancer: a pooled analysis from the international head and neck cancer epidemiology consortium

Abstract

Background: A history of diabetes is associated with an increased risk of several types of cancers. Whether diabetes is a risk factor for head and neck cancer (HNC) has received little attention.

Methods: We pooled data from 12 case-control studies including 6,448 cases and 13,747 controls, and estimated OR and 95% CI for the associations between diabetes and HNC, adjusted for age, education level, sex, race/ethnicity, study center, cigarette smoking, alcohol use, and body mass index.

Results: We observed a weak association between diabetes and the incidence of HNC overall (OR, 1.09; 95% CI: 0.95-1.24). However, we observed a modest association among never smokers (OR, 1.59; 95% CI: 1.22-2.07), and no association among ever smokers (OR, 0.96; 95% CI: 0.83-1.11); likelihood ratio test for interaction P = 0.001.

Conclusion: A history of diabetes was weakly associated with HNC overall, but we observed evidence of effect modification by smoking status, with a positive association among those who never smoked cigarettes.

Impact: This study suggests that glucose metabolism abnormalities may be a HNC risk factor in subgroups of the population. Prospective studies incorporating biomarkers are needed to improve our understanding of the relationship between diabetes and HNC risk, possibly providing new strategies in the prevention of HNC.

Figure 1. Forest plot of study-specific ORs and 95% CIs for the association between history of diabetes and HNC risk, INHANCE Pooled Case-Control Study of Head and Neck Cancer

The squares represent the OR estimates and the horizontal lines represent the 95% CIs for each study. The area of the square reflects the weight that the study contributes. This random-effects model incorporates an estimate of between-study heterogeneity in the weighting. The diamond at the center indicates the random-effects estimate and the width of the diamond indicates the 95% CI.

Figure 2. Influence analyses of single studies on the overall estimate for the association between history of diabetes and HNC risk, INHANCE Pooled Case-Control Study of Head and Neck Cancer

The circle for each study represents the OR estimate and the horizontal line represents the 95% CI from the pooled data after excluding that study. The three vertical lines represent the random-effects pooled point estimate and associated 95% CI.