Background: Smoking is a recognised risk factor for pancreatic cancer and has been associated with chronic pancreatitis and also with type II diabetes. Aims: The aim of this study was to investigate the effect of tobacco on the age of dia gnosis of pancreatitis and progression of disease, as measured by the appearance of calcification and diabetes. Patients: We used data from a retrospective coho rt of 934 patients with chronic alcoholic pancreatitis where information on smok ing was available,who were diagnosed and followed in clinical centres in five co untries. Methods: We compared age at diagnosis of pancreatitis in smokers versus non-smokers, and used the Cox proportional hazards model to evaluate the effec ts of tobacco on the development of calcification and diabetes, after adjustment for age, sex, centre, and alcohol consumption. Results: The diagnosis of pancre atitis was made, on average, 4.7 years earlier in smokers than in non-smokers ( p = 0.001). Tobacco smoking increased significantly the risk of pancreatic calci fications(hazard ratio (HR) 4.9 (95%confidence interval (Cl) 2.3-10.5)for smok ers v non-smokers) and to a lesser extent the risk of diabetes (HR 2.3 (95%Cl 1.2-4.2)) during the course of pancreatitis. Conclusions: In this study, tobacc o smoking was associated with earlier diagnosis of chronic alcoholic pancreatiti s and with the appearance of calcifications and diabetes,independent of alcohol consumption. Background: Smoking is a recognized risk factor for pancreatic cancer and has been associated with chronic pancreatitis and also with type II diabetes. Aims: The aim of this study was to investigate the effect of tobacco on the age of dia gnosis of pancreatitis and progression of Patients, We used data from a retrospective coho rt of 934 patients with chronic alcoholic pancreatitis where information on smok ing was available, who were diagnosed and followed in clinical centers in five co untries. Methods: We compared age at diagnosis of pancreatitis in smokers versus non-smokers, and used the Cox proportional hazards model to evaluate the effec ts of tobacco on the development of calcification and diabetes, after adjustment for age, sex, center, and alcohol consumption Results: The diagnosis of pancreitis was made, on average, 4.7 years earlier than smokers than in non-smokers (p = 0.001). Tobacco smoking increased (hazard ratio (HR) 4.9 (95% confidence interval (Cl) 2.3-10.5) for smok ers v non-smokers) and to a lesser extent the risk of diabetes (HR 2.3 1.2-4.2)) during the course of pancreatitis. Conclusions: In this study, tobacco smoking was associated with earlier diagnosis of chronic alcoholic pancreatiti s and with the appearance of calcifications and diabetes, independent of alcohol consumption.