Evaluating the Incidence and Risk Factors Associated With Mild and Severe Hypoglycemia in Insulin-Treated Type 2 Diabetes

Objectives: This study to assess the incidence rates and risk factors of hypoglycemia in a wide real-life sample of patients with insulin-treated type 2 diabetes mellitus. Methods: In a prospective epidemiological study, data from 817 subjects were collected from medical records and via interviews. Over a 3-month period, hypoglycemic episodes were recorded via self-measurement of glucose levels at least twice daily. Cox proportional and negative binomial multivariable models were applied to estimate adjusted and unadjusted hazard ratios and incidence rate ratios of hypoglycemic events. Results: Of the 817 patients, 52.9% experienced hypoglycemia, 38.1% had only nonsevere episodes, and 14.8% had at least 1 severe episode. Total events per patient-year were estimated at 13.3 (+/- 24.8), with 11.8 (+/- 21.6) and 1.4 (+/- 4.7) being nonsevere and severe, respectively. History of hypoglycemia and severe hypoglycemia were consistent risk factors of hypoglycemia. Intensification of therapy was associated with higher incidence rates, whereas the effect on the hazard rates was more moderate. Longer duration of insulin therapy and the presence of congestive heart failure were associated with a higher risk of developing and frequency of hypoglycemia. Hypoglycemia awareness was found to independently affect only mild hypoglycemia. Conclusions: Hypoglycemia is a common complication in patients with insulin-treated type 2 diabetes mellitus. The risk factors of developing hypoglycemia are to some extent different from those of the frequency of hypoglycemic episodes. Particular attention is required for patients with recurrent hypoglycemic events and on intensive antidiabetic therapy.