Objective: Hyperglycaemia in type 2 diabetes is caused by varying degrees of two defects: low insulin sensitivity and beta-cell dysfunction. We assessed if subgrouping of patients into three pathophysiological phenotypes according to these defects could identify individuals with high or low risk of future cardiovascular events.
Design: This is a prospective cohort study.
Methods: We assessed estimates of insulin sensitivity and beta-cell function from the homeostasis model assessment-2 in 4209 individuals with recently diagnosed type 2 diabetes enrolled from general practitioners and outpatient clinics in Denmark. Individuals were followed for a composite cardiovascular endpoint (either atherosclerotic outcomes (myocardial infarction, unstable angina pectoris, stroke, coronary or peripheral revascularization), heart failure, or cardiovascular death) and all-cause mortality.
Results: Totally 417 individuals with the insulinopenic phenotype (high insulin sensitivity and low beta-cell function) had substantially lower risk of cardiovascular events (5-year cumulative incidence: 4.6% vs 10.1%; age-/sex-adjusted hazard ratio (aHR): 0.49; 95% CI: 0.30-0.82) compared with 2685 individuals with the classical phenotype (low insulin sensitivity and low beta-cell function), driven by atherosclerotic events. Conversely, 1107 individuals with the hyperinsulinaemic phenotype (low insulin sensitivity and high beta-cell function) had more cardiovascular events (5-year cumulative incidence: 12.6%; aHR: 1.33; 95% CI: 1.05-1.69), primarily driven by increased heart failure and cardiovascular death and increased all-cause mortality.
Conclusions: Simple phenotyping based on insulin sensitivity and beta-cell function predicts distinct future risks of cardiovascular events and death in patients with type 2 diabetes. These results suggest that precision medicine according to underlying type 2 pathophysiology potentially can reduce diabetes complications.