Incidence and prognostic significance of hypoglycemia in hospitalized non-diabetic elderly patients

BACKGROUND AND AIMS: To assess the incidence and prognostic value of hypoglycemia in hospitalized non-diabetic elderly patients. METHODS: An observational retrospective study, with a 3-year follow-up, was performed in a series of 678 patients aged over 65 years, admitted between January 1 2001 and December 31 2001 to the Units of Gerontology and Geriatrics of the Careggi University Hospital, Florence, Italy. Patients with diabetes mellitus were excluded. To determine the cumulative incidence of hypoglycemia, all measurements of venous or capillary blood glucose during hospital stay were taken into account. In-hospital mortality was determined from hospital discharge records. Information on all-cause, three-year mortality after hospital admission was obtained from the City of Florence Registry Office. RESULTS: Hypoglycemia was observed in 8.6% of patients, and was asymptomatic in about 25% of cases. In-hospital mortality was significantly higher in patients with hypoglycemia (41.4% vs 14.3%; p<0.001), even after adjustment for potential confounders, including comorbidity, indices of malnutrition, and pharmacological treatment (adjusted OR 2.17[1.25;3.85]). 3-year mortality was significantly higher in patients with hypoglycemia during hospital stay, but the difference was not significant after adjustment for confounders. CONCLUSIONS: Hypoglycemia is a prognostic marker of in-hospital mortality in non-diabetic hospitalized patients, even after adjustment for comorbidity and indices of malnutrition. Instead, it does not seem to have any relevant independent prognostic value in the longer term.