Hospitalization for hypoglycaemia in people with diabetes in Denmark, 1997-2017: Time trends in incidence and HbA and glucose-lowering drug use before and after hypoglycaemia.

Objective: To assess incidence trends of first hospitalization for hypoglycaemia in Denmark and to examine HbA levels and glucose-lowering drug use before and after hospitalization among individuals with type 1 or type 2 diabetes.

Research Design And Methods: We performed a population-based study linking diagnosis, prescription and laboratory data. Standardized incidence of first hospitalization for hypoglycaemia in Denmark was assessed for each calendar year 1997-2017. HbA1c and glucose-lowering drug use was compared with age- and sex-matched diabetes comparisons without hospitalization for hypoglycaemia.

Results: The annual age- and sex-standardized incidence rate of first hospitalization for hypoglycaemia per 100,000 person-years increased during 1997-2003 (from 17.7 to 30.3 per 100,000 person-years), remained stable until 2010 (30.4) and gradually declined until 2017 (22.0). During this period, we identified 3,479 people with type 1 diabetes and 15,329 people with type 2 diabetes experiencing first hospitalization for hypoglycaemia. Both diabetes groups experienced a mean HbA1c decrease of ~12%-15% in the months preceding first hospitalization, followed by a gradually increasing HbA1c afterwards. People with type 1 diabetes and hospitalization used similar insulin therapies as those without hospitalization. People with type 2 diabetes and hospitalization more often received insulin (55%) than comparisons (45%), and 45% discontinued insulin or stopped all glucose-lowering therapy after first hospitalization.

Conclusions: Incidence of hospitalizations for hypoglycaemia has declined by one fourth the last decade in the Danish population. A HbA1c decrease precedes first hospitalization for hypoglycaemia in individuals with diabetes, and profound changes in glucose-lowering drug therapy for type 2 diabetes occur after hospitalization.