Abstract

Background: The study aims to estimate the incidence of pancreatic cancer in people with new-onset type 2 diabetes (T2DM) and examine the connection between pancreatic cancer risk, age at diagnosis, and duration of diabetes.

Methods: Mendelian randomization (MR) in the east-Asian population and this longitudinal cohort study with 428,362 new-onset T2DM patients in Shanghai were used to investigate the association. All patients' and subgroups' incidence rates of pancreatic cancer were calculated and compared to the general population.

Result: During eight years of follow-up, a total of 1056 incident cases of pancreatic cancer were identified. T2DM patients had a standardized incidence ratio (SIR) of 154 (95% CI, 145–164), which was higher than the general population's annual pancreatic cancer incidence rate of 5528/100,000 person years. The older groups with T2DM had a significantly higher incidence of pancreatic cancer, which increased with age. However, the 20–54-year-old group had a higher SIR of 573 (95% CI, 449–722) and a relative risk of pancreatic cancer that was inversely related to age of T2DM onset. Any duration of diabetes was associated with an increased risk of pancreatic cancer. Pancreatic cancer was linked to fasting blood glucose levels below 10 mmol/L. T2DM had a positive correlation with the risk of pancreatic cancer, according to MR analysis.

Interpretation: Efforts toward early and close follow-up programs, particularly in people with young-onset T2DM, and the improvement of glucose control might be effective strategies for improving the detection of pancreatic cancer and the outcomes of its treatment.