Inpatient glycemic variability and long-term mortality in hospitalized patients with type 2 diabetes

Aims/Hypothesis: To determine the association between inpatient glycemic variability and long-term mortality in patients with type 2 diabetes mellitus.Methods: Capillary blood glucose (CBG) of inpatients from 8 hospitals was analysed. 28,353 admissions identified were matched for age, duration of diabetes and admission and median and interquartile range of CBG. 6year mortality was investigated for (i) those with CBG IQR in the top half of all IQR measurements (matched for all except IQR), vs those in the lower half and (ii) those with the lowest quartile median glucose (matched for all except median).Results:1. Glycemic variability3165 matched pairs were analysed. Mortality was greater in those with IQR in upper 50% (≥50.9 mg/dl)over follow-up from day 90 post-discharge to a maximum of 6 years (p<0.01, HR 1.17).2. Median glucose2.3755 matched pairs were analysed. Mortality was lower in those with a median glucose in upper 50% (≥148.5 mg/dl) over follow-up from day 90 post-discharge to a maximum of 6 years (p < 0.01, HR 0.87).Conclusion: Higher inpatient glycemic variability is associated with increased mortality on long-term follow up. When matched by IQR, we have demonstrated higher median CBG is associated with lower long-term mortality. CBG variability may increase cardiovascular morbidity by increasing exposure to hypoglycaemia or to variability per se. In hospitalized patients with diabetes, glycemic variability should be minimised and when greater CBG variability is unavoidable, a less stringent CBG target considered.