Diabetes mellitus correlates with increased risk of pancreatic cancer: A population-based cohort study in Taiwan

Background and Aim: This study investigated whether diabetes mellitus (DM) increased the risk of pancreatic cancer and whether anti-diabetic drugs reduced the risk in Taiwan. Methods: We designed a population-based cohort study using the Taiwan National Health Insurance Database, which consisted of 49 803 patients aged 20 years and older with newly diagnosed DM as the diabetic group and 199 212 people without DM as the non-diabetic group during 1998-2007. Results: The incidence of pancreatic cancer was higher in patients with diabetic duration less than 2 years, as compared to the non-diabetic group (27.81 vs 6.96 per 10 000 person-years, 95% confidence interval = 2.11-7.54). Age (aged 40-64, hazard ratio [HR] = 5.22, and aged 65 and older, HR = 7.59, respectively), chronic pancreatitis (HR = 19.40), gallstones (HR = 2.56), and hepatitis C infection (HR = 3.08) were also significant factors predicting pancreatic cancer. Patients with concurrent DM and chronic pancreatitis had an appreciably elevated risk of developing pancreatic cancer (HR = 33.52), as compared with subjects without these comorbidities. The association was not statistically significant between use of anti-diabetic drugs and the risk of pancreatic cancer. Conclusions: Diabetes < 2 years' duration is associated with pancreatic cancer and could be an early manifestation of pancreatic cancer. Long-standing diabetes was not found to be a risk factor for pancreatic cancer in Taiwan's patients. Old age, chronic pancreatitis, gallstones and hepatitis C infection are other risk factors for pancreatic cancer. These high-risk patients should undergo close follow-up programs for pancreatic cancer.