Mortality experience in relation to tobacco chewing and smoking habits from a 10-year follow-up study in Ernakulam District, Kerala.

Mortality experience of a cohort of 10 287 individuals age 15 years and over selected by random sampling in Ernakulam district of Kerala was recorded in house-to-house surveys over a 10-year period. Mortality rates were analysed according to tobacco habits of chewing and smoking, taking-age and sex distribution into consideration. Tobacco chewing was practised most commonly by females and these females had significantly higher age-adjusted mortality rates than those who did not use tobacco (relative risk 1.3). Excess mortality among male bidi smokers (relative risk 1.5) was also significant and comparable to the excess mortality among cigarette smokers reported from Western countries.