Background: Type 2 diabetes mellitus (T2DM) has been suggested to increase the risk of cancers. The aim of this study was to evaluate the secular trend for cancer incidence in T2DM patients in Minhang District of Shanghai and the incidence rate ratios from cancer between T2DM patients and the general population between 2004 and 2014.

Methods: All T2DM patients were enrolled from the standardized management system based on local electronic information system in Minhang District of Shanghai, China. Newly-diagnosed cancer cases were identified by record-linkage with the Shanghai Cancer Registry. The incidence rates (per 100,000) from cancer according to age for the T2DM patients for each year between 2004 and 2014 were calculated. Age-specific incidence from cancer for T2DM patients and their Standardized incidence ratios (SIR) and 95% confidence interval (CI) compared with the general population were estimated.

Results: A total of 2593 T2DM patients (1317 male and 1276 female) aged ≥40 years were included. A trend for an increase in the annual rate was observed for all age groups. The incidence (per 1000, 000) from cancer was 997.17 in male and 829.57 in female, with age-standardized rate (ASR) being 207.12 and 218.57, respectively. The incidence from cancer showed an upward trend with age compared with the general population, except the age of 40- and 45- year in female T2DM patients. The incidence from cancer was 588.16 at ages of 40- years, and 548.79 at ages of 45- years in female. Compared with the general population, an increased risk was observed in female patients, with SIRs being 2.15 (95% CI: 1.13-3.17) at ages of 40- years and 1.49 (95% CI: 1.05-1.93) at ages of 45- years.

Conclusions: We identified a secular trend of an increase in the rate of cancer incidence in the T2DM patients by ages. Our results suggested that a higher risk of cancer incidence in female T2DM patients at age of 40- and 45-years compared with the general population.


Q. Guo: None. H. Xu: None. D. Xu: None.

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