Effect of alcohol and smoking on pancreatic lithogenesis in the course of chronic pancreatitis

The aim of the study was to establish whether correlations were discernible between calcification, smoking, and other variables--including alcohol intake--in chronic pancreatitis. A total of 637 patients with chronic pancreatitis diagnosed over the period of 1973-1989 were reviewed. Only patients who had had one or more instrumental tests (ultrasonography, endoscopic retrograde cholangiopancreatography, computed tomography, plain film of the abdomen) every 3 years were included in the study. Onset of calcification was taken as the end point of the follow-up. No statistically significant correlation was found between alcohol intake and calcification. As regards smoking habits, patients were divided into two groups: nonsmokers and medium-to-heavy smokers (> or = 10 cigarettes/day). Of 637 patients, only 570 fulfilled our criteria. Three hundred seventy-six patients (66%) developed calcifications, whereas 64 (10%) already presented calcifications at the time of diagnosis. Smoking correlated with formation of calcifications (p < 0.004). The mean time to onset of calcification in smokers was 8 years as against 12 years in nonsmokers. The relative risk of calcification in smokers versus nonsmokers was 1.21 (95% confidence limits: 1.10-1.32). By the end of follow-up (17 years), 277 smokers (69%) with chronic pancreatitis had developed calcifications compared with only 93 nonsmokers (55%). The results show that, in this sample of chronic pancreatitis sufferers, smokers present a significantly increased risk of developing calcifications.