Association of prediabetes with death and diabetic complications in older adults: the pros and cons of active screening for prediabetes

Abstract Background active screening can improve health outcomes for people with prediabetes. However, its efficacy in older adults remains uncertain. Objective the study aimed to analyse the progression from prediabetes to diabetes in older adults, including associated complications and mortality rates, to determine the benefits of active screening. Design retrospective cohort study. Setting Korean National Health Insurance Service claims database. Subjects a total of 36,946 adults aged ≥65 years who underwent national health examinations from 2006 to 2008. Methods follow-up was until 31 December 2015. Cox’s proportional hazards models estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for death and diabetic complications. Results over a median follow-up of 8.2 years, 19.3% of older adults with prediabetes progressed to diabetes. Compared with normoglycaemic adults, the multivariable-adjusted HRs (95% CI) for major adverse cardiovascular events were 1.01 (0.95–1.07), 1.08 (0.95–1.23), 1.14 (1.05–1.23) and 1.50 (1.35–1.68) in adults with prediabetes, newly diagnosed diabetes, diabetes not on insulin and diabetes on insulin, respectively. The corresponding HRs (95% CI) for diabetic retinopathy risk were 1.28 (1.15–1.43), 3.16 (2.71–3.69), 6.58 (6.02–7.19) and 9.17 (8.21–10.24). Diabetic nephropathy risk also significantly increased. Conclusions progression from prediabetes to diabetes is an important concern among older adults. Prediabetes is associated with the risk of microvascular complications, but not cardiovascular complications and mortality. Therefore, active regular screening for prediabetes is necessary to prevent microvascular complications.