Epidemiologic study of the association between alcohol habits and oral leukoplakia.

In a house-to-house survey in Ernakulam district, Kerala State, 10914 individuals were interviewed for their tobacco and alcohol habits and examined for the presence of oral leukoplakia. Very few females (1.6%) were found to be alcohol users and they were excluded from further analysis. Among 7604 males, 30.4% used alcohol regularly, 25.4% occasionally and 44.2% were non-users. The prevalence of leukoplakia was significantly higher among regular (5.7%) and occasional (3.9%) users than among non-users (2.9%) of alcohol. Alcohol usage was found to be related to age as well as tobacco habits. The prevalence of leukoplakia was higher among alcohol users in each age-group as well as in each tobacco habit category. After age-adjustment the difference between alcohol users and non-users, although reduced, remained significant. For most tobacco habit categories the trend remained similar after age-adjustment except for the mixed habits group, for which there was a reversal of the trend. The alcohol habit may, perhaps, produce discernible effects only in association with other 'weak' etiological risk factors, such as a single tobacco habit of smoking or chewing rather than a 'strong' etiologic factor such as the mixed habits of chewing and smoking.