Aims: To compare non-fatal cardiovascular (CV) events and metabolic outcomes, among obese patients with insulin-treated type 2 diabetes who underwent bariatric surgery compared with a propensity-matched non-bariatric cohort.
Methods: A retrospective cohort study was conducted among 11,125 active patients with type 2 diabetes from The Health Improvement Network (THIN) database. Propensity score matching (up to 1:6 ratio) was used to identify patients who underwent bariatric surgery (N = 131) with a non-bariatric cohort (N = 579). Follow-up was undertaken for 10 years (9686 person-years) to compare differences in metabolic outcomes and CV risk events that included the following: acute myocardial infarction (AMI), stroke, coronary heart disease (CHD), heart failure (HF) and peripheral artery disease (PAD). Cox proportional regression was used to compute the outcomes between groups.
Results: The mean age was 52 (SD 13) years (60% female); the baseline weight and BMI were 116 (SD 25) kg and 41 (SD 9) kg/m2, respectively. Significant reductions in weight and BMI were observed in bariatric group during 10 years of follow-up. Bariatric surgery had a significant cardioprotective effect by reducing the risk of non-fatal CHD (adjusted hazard ratio [aHR] 0.29, 95% CI 0.16-0.52, p < 0.001) and PAD events (aHR 0.31, 95% CI 0.11-0.89, p = 0.03). However, the surgery had no significant effect on AMI (aHR 0.98, p = 0.95), stroke (HR 0.87, p = 0.76) and HF (HR 0.89, p = 0.73) risks. Bariatric surgery had favourable effects on insulin independence, HbA1c and BP.
Conclusion: Among obese insulin-treated patients with type 2 diabetes, bariatric surgery is associated with significant reductions in non-fatal CHD and PAD events, lower body weight, HbA1c, BP and a greater likelihood of insulin independency during 10 years of follow-up.
Keywords: Bariatric; Cardiometabolic; Cardiovascular; Insulin; Obesity; Peripheral vascular disease; Type 2 diabetes; Weight loss.