Cigarette smoking as a risk factor for chronic pancreatitis: a case-control study in Japan. Research Committee on Intractable Pancreatic Diseases.

We conducted a hospital-based, case-control study to examine the association of cigarette smoking with chronic pancreatitis. Ninety-one male patients with chronic pancreatitis newly diagnosed from July 1997 to December 1998 were recruited as cases, and 175 controls were individually matched to each case for gender, age (+/- 5 years), hospital, and time of the first visit to a hospital (+/- 1 year). A self-administered questionnaire was used to collect information on tobacco and alcohol use, diet, and other factors. The odds ratios (ORs) and their 95% confidence intervals (CIs) were calculated by multiple conditional logistic models, adjusting for body mass index, education level, and alcohol consumption. Compared with nonsmokers, the ORs (95% CIs) were 7.8 (2.2-27.3) for all current smokers, and 14.7 (3.1-69.9), 5.5 (1.5-20.1), 12.2 (2.4-71.0) for those consuming < 20, 20-39, and > or = 40 cigarettes per day, respectively. Much greater risk was observed for those who had smoked for > or = 25 years. Risk of chronic pancreatitis significantly increased with increasing cumulative amount of smoking (p < 0.05). Analysis for the effect of combined use of tobacco and alcohol showed that cigarette smoking was associated with the higher risk in both of the two alcohol consumption levels. Our findings indicated that cigarette smoking may be an independent and significant risk factor for chronic pancreatitis.