Severe Hypoglycemia, Cardiac Structure and Function, and Risk of Cardiovascular Events Among Older Adults With Diabetes

OBJECTIVE: To assess the association of severe hypoglycemia measured at baseline with cardiovascular disease (CVD) among community-dwelling older individuals with diabetes, a group particularly susceptible to hypoglycemia. RESEARCH DESIGN AND METHODS: We included older adults with diabetes from the Atherosclerosis Risk in Communities (ARIC) study who attended visit 5 (2011-2013, baseline). Severe hypoglycemia at baseline was defined with use of first position ICD-9 codes from hospitalizations, emergency department visits, and ambulance calls. We examined cross-sectional associations of severe hypoglycemia with echocardiographic indices of cardiac structure-function. We prospectively evaluated the risks of incident or recurrent CVD (coronary heart disease, stroke, or heart failure) and all-cause mortality, from baseline to 31 December 2018, using negative binomial and Cox regression models. RESULTS: Among 2,193 participants (mean [SD] age 76 [5] years, 57% female, 32% Blacks), 79 had a history of severe hypoglycemia at baseline. Severe hypoglycemia was associated with a lower left ventricular (LV) ejection fraction (adjusted β-coefficient -3.66% [95% CI -5.54, -1.78]), higher LV end diastolic volume (14.80 mL [95% CI 8.77, 20.84]), higher E-to-A ratio (0.11 [95% CI 0.03, 0.18]), and higher septal E/e' (2.48 [95% CI 1.13, 3.82]). In adjusted models, severe hypoglycemia was associated with incident or recurrent CVD (incidence rate ratio 2.19 (95% CI 1.24, 3.88]) and all-cause mortality (hazard ratio 1.71 [95% CI 1.10, 2.67]) among those without prevalent CVD. CONCLUSIONS: Our findings suggest that a history of severe hypoglycemia is associated with alterations in cardiac function and is an important marker of future cardiovascular risk in older adults.