Smoking history and survival among lung cancer patients

Two population-based case-control studies of lung cancer were conducted on the Island of Oahu, Hawaii, between 1979 and 1985. Interview information concerning smoking habits and other characteristics was obtained from a total of 463 men and 212 women with histologically confirmed lung cancer. Records from the Hawaii Tumor Registry were reviewed for information on the stage, histology, and follow-up status of these patients. Cigarette smoking was found to be positively related to the age-adjusted risk of death among women (relative risk (RR) = 1.6; 95 percent confidence interval (CI) = 1.0-2.4), but not among men (RR = 0.8; 95 percent CI = 0.5-1.2). Among women, the age-adjusted median survival time for never smokers was 33 months (n = 53) compared with a median survival of 18 months (n = 159) for smokers. Both past and current female smokers were at greater risk of death than never-smokers, and there was a significant trend in the risk of death by the number of cigarettes smoked per day (P = 0.04), and the age at which the subjects started smoking (P = 0.01). The effects of tumor stage and histology upon the association between tobacco smoking and survival were also explored.