Cigarette smoking and alcohol consumption as determinants of survival in non-Hodgkin's lymphoma: a population-based study

Background: The risk of non-Hodgkin's lymphoma (NHL) seems to be enhanced by cigarette smoking and lowered by alcohol drinking. Patients and methods: To assess whether cigarette smoking and alcohol drinking affect NHL survival, a population-based prospective study on 1138 Italian patients, diagnosed in 1991-1993, followed-up until 2002, was carried out. At diagnosis, clinical and socio-demographic data were recorded and lifestyle habits were assessed through a validated questionnaire. Survival analysis was performed with Kaplan-Meier methods. Hazard ratios (HR) were estimated by Cox regression. Results: The mean follow-up was 6.6 years (standard deviation (SD) 4.3). The mean survival time was 7.56 years (SD 0.155). At both univariate and multivariate analysis heavy cigarette smoking and alcohol drinking were associated with poor survival. Compared with those with a lower cumulative exposure to tobacco smoking, those who had smoked > 31 pack-years had a worse survival (HR = 1.60, 95%CI = 1.18-2.18). Drinkers had a higher risk of death compared with non-drinkers (HR = 1.41, 95%CI = 1.10-1.81). Considering only those who had NHL as cause of death, the HR for the higher category of pack-years smoked, compared with the lowest, was 1.63 (95% CI = 1.15-2.33) and for drinkers, compared with non-drinkers, it was 1.33 (95% CI = 1.01-1.80). Conclusions: cigarette smoking and alcohol drinking may influence NHL survival.