Improvement of diabetes and hypertension after gastrectomy: a nationwide cohort study.

Aim: To evaluate the effect of gastrectomy on diabetes mellitus (DM) and hypertension (HTN) in non-obese gastric cancer patients.

Methods: A total of 100000 patients, diagnosed with either type 2 DM or HTN, were randomly selected from the 2004 Korean National Health Insurance System claims. Among them, 360 diabetes and 351 hypertensive patients with gastric cancer who had been regularly treated without chemotherapy from January 2005 to December 2010 were selected. They were divided into three groups according to their treatment methods: total gastrectomy (TG), subtotal gastrectomy (STG) and endoscopic resection (ER).

Results: The drug discontinuation rate of anti-diabetic and anti-hypertensive agents after gastric cancer treatment was 9.7% and 11.1% respectively. DM appeared to be improved more frequently (22.8%) and earlier (mean±SE 28.6±1.8 mo) in TG group than in the two other groups [improved in 9.5% of ER group (37.4±1.1 mo) and 6.4% of STG group (47.0±0.8 mo)]. The proportion of patients treated with multiple drugs decreased more notably in TG group compared to others (P=0.001 in DM, and P=0.035 in HTN). In TG group, adjusted hazard ratio for the improvement of DM was 2.87 (95%CI: 1.15-7.17) in a multi-variate analysis and better control of DM was observed with survival analysis (P<0.001).

Conclusion: TG was found to decrease the need for anti-diabetic medications which can be reflective of improved glycemic control, to a greater extent than either ER or STG in non-obese diabetic patients.