Temporal trends in cardiovascular outcomes and costs among patients with type 2 diabetes

Abstract

Background: Type 2 diabetes (T2D) is a strong risk factor for cardiovascular (CV) disease. CV outcomes in T2D have generally been improving over time but recent data from the US suggest attenuation of trends in older adults with reversal of trends in younger adults. However, published data are only reported through 2015.

Objectives: To quantify trends over time in CV outcomes from 2001 to 2018, and describe changes over time in health care costs in T2D.

Methods: This retrospective cohort study incorporated data from a regional health insurance plan. Study outcomes included acute myocardial infarction (AMI), ischemic stroke, hemorrhagic stroke, heart failure hospitalization (HFH), percutaneous coronary intervention, coronary artery bypass surgery, and all-cause mortality. Poisson regression estimated rate ratios across the entire 17-year study period (RR¹⁷).

Results: Among 79,392 T2D members tracked on average 4.1 years, overall trends in AMI (RR¹⁷ = 0.69; 95% CI: 0.64, 0.74), HFH (RR¹⁷ = 0.82; 0.79, 0.86), and all-cause mortality (RR¹⁷ = 0.87; 0.84, 0.91) improved while ischemic stroke (RR¹⁷ = 2.36; 2.16, 2.57) worsened. For AMI, HFH, and all-cause mortality, trends in older age groups were significantly better than in younger age groups (interaction P-values < .001). Health care costs related to pharmaceuticals (+15%/year) and emergency department (ED) visits (>15%/year) increased at faster rates than other utilization metrics (+10%/year).

Conclusions: In T2D, overall trends in most CV outcomes improved but smaller improvements or worsening trends were observed in younger patients. Health care costs accelerated at faster rates for medications and ED visits.