Estimating the risk of severe hypoglycemic event related to glucose-lowering treatment among Italian patients with diabetes: the HYPOTHESIS database

The primary objective of this study was to estimate 1) the annual risk of undergoing a severe hypoglycemic event in Italian patients with diabetes and 2) the risk of hospitalization following such event. From the HYPOTHESIS database, powered by 46 emergency departments covering a 12-million-odd population, data were extracted of 1,922 hypoglycemic events occurring in patients with diabetes in 2011. The mean age was 71.5 (standard deviation 16.8) years, 50.1% were men, and blood glucose at the time of the event was 44.2 (26.5) mg/dL. Patients were being treated with insulin alone (55%) or in combination with oral hypoglycemic agents (OHA, 15%), or with OHA alone, either in monotherapy (14%) or in multiple therapy (16%). Comorbidities were recorded in 71.8% of the patients. Based on the rates of glucose-lowering drug use in Italian patients with diabetes, the annual risk of undergoing a serious hypoglycemic event was estimated at 1.27% for subjects treated with insulin alone, the highest (p<0.00001) as compared with insulin + OHA (0.41%) or OHA alone, either in monotherapy or in multiple therapy (0.1% and 0.17%, respectively). The risk of being hospitalized following the hypoglycemic event was the least (27.6%) for subjects treated with insulin alone (p<0.0083). Subjects treated with insulin + OHA showed a lower risk (34.2%) as compared with that for subjects treated with OHA (p<0.02). Death occurs in 7% of hospitalized patients. Older age (p<0.0001) and comorbidities (p<0.0001) were risk factors for hypoglycemia-related hospitalization. Treatments with insulin alone (p<0.005) or in combination (p<0.049) were negatively associated with hospital admission. Severe hypoglycemic events associated with the use of oral glucose-lowering agents carry the highest risk of hospital treatment. As such, they are also likely to generate higher tangible and intangible costs.