Epidemiology Unit, Local Health Authority of Reggio Emilia, IRCCS, Reggio Emilia, Italy.
Department of Internal Medicine, Hospital of Montecchio, Local Health Authority of Reggio Emilia, Reggio Emilia, Italy.
BMC Cancer. 2017 Oct 25;17(1):703. doi: 10.1186/s12885-017-3696-4.
Aim of this study was to compare cancer incidence in populations with and without diabetes by cancer site. Furthermore, we aimed at comparing excess risk of cancer according to diabetes type, diabetes duration and treatment, the latter as regards Type 2 diabetes.
By use of the Reggio Emilia diabetes registry we classified the resident population aged 20-84 at December 31 2009 into two groups: with and without diabetes. By linking with the cancer registry we calculated the 2010-2013 cancer incidence in both groups. The incidence rate ratios (IRR) by cancer site, type of diabetes, diabetes duration, and as concerns Type 2 diabetes, by treatment regimen were computed using Poisson regression model and non-diabetic group as reference.
The cohort included 383,799 subjects without diabetes and 23,358 with diabetes. During follow-up, we identified 1464 cancer cases in subjects with diabetes and 9858 in the remaining population. Overall cancer incidence was higher in subjects with diabetes than in those without diabetes (IRR = 1.22, 95%CI 1.15-1.29), with similar results focusing on subjects with at least 2-year diabetes duration. Cancer sites driving overall increased risk were liver, pancreas, Colon rectum, and bladder in both sexes, corpus uteri for females. There was also suggestion of an increased risk for kidney cancer in females and a decreased risk for prostate cancer. Excess risk was found in patients with Type 2 diabetes, more marked among insulin users, especially with combined therapy. We observed an increasing risk for diabetes duration up to 10 years from diagnosis (IRR = 1.44, 95%CI 1.29-1.61) and a subsequent decrease to moderate-higher risk (IRR = 1.15, 95%CI 1.04-1.30).
Our study indicates that the strength of association depends on specific cancer site. Insulin, monotherapy or combined therapy, per se or as an indication of poor blood glucose control, in addition to diabetes duration, may play a role in the association of diabetes and cancer.
本研究旨在按癌症部位比较有糖尿病和无糖尿病人群的癌症发病率。此外，我们旨在比较根据糖尿病类型、糖尿病病程和治疗方法（针对 2 型糖尿病）的癌症风险增加情况。
利用雷焦艾米利亚糖尿病登记处，我们将 2009 年 12 月 31 日年龄在 20-84 岁的居民分为两组：有糖尿病和无糖尿病。通过与癌症登记处的链接，我们计算了两组 2010-2013 年的癌症发病率。使用泊松回归模型和无糖尿病组作为参照，计算了按癌症部位、糖尿病类型、糖尿病病程以及针对 2 型糖尿病的治疗方案的发病率比值比（IRR）。
队列包括 383799 名无糖尿病患者和 23358 名有糖尿病患者。在随访期间，我们在有糖尿病的患者中发现了 1464 例癌症病例，在其余人群中发现了 9858 例。与无糖尿病患者相比，糖尿病患者的总体癌症发病率更高（IRR=1.22，95%CI 1.15-1.29），对于糖尿病病程至少 2 年的患者也有类似的结果。在男女两性中，导致总体风险增加的癌症部位为肝脏、胰腺、结肠直肠和膀胱，女性为子宫体。女性中也有肾癌风险增加的迹象，而前列腺癌风险降低。2 型糖尿病患者存在过度风险，胰岛素使用者的风险更为显著，尤其是联合治疗者。我们观察到从诊断起 10 年的糖尿病病程呈增加趋势（IRR=1.44，95%CI 1.29-1.61），随后风险降低至中高水平（IRR=1.15，95%CI 1.04-1.30）。
我们的研究表明，关联的强度取决于特定的癌症部位。胰岛素、单药治疗或联合治疗，本身或作为血糖控制不佳的指征，以及糖尿病病程，可能在糖尿病与癌症的关联中发挥作用。
