Epidemiology of hypoglycaemic episodes leading to hospitalisations in Denmark in 1998-2018

We aimed to investigate the nationwide trends in incidence and associated risk factors, with focus on blood glucose-lowering medication, for the first hypoglycaemic episode leading to hospitalisation in Denmark among people with type 1 and 2 diabetes mellitus.

A cohort study of all people with diabetes from 1977 to 2018 experiencing hypoglycaemic episodes leading to hospitalisation in 1998-2018 was established. Data were extracted from the Danish National Patient Registry. Trends in incidence rates were investigated with Poisson regression models and linear regressions, and risk factors were investigated with Cox proportional hazards models.

A total of 66,438 hypoglycaemic episodes leading to hospitalisation in 1998-2018 was investigated among 641,402 people with type 1 (mean ± SD age 37 ± 22 years) and type 2 diabetes (mean ± SD age 61 ± 17 years). Between 2003 and 2018, the incidence rate fell by 66% for type 1 diabetes (incidence rate ratio [IRR] 0.34 [95% CI 0.31, 0.36], p < 0.0001) and 61% for type 2 diabetes (IRR 0.39 [95% CI 0.36, 0.42], p < 0.0001). With respect to hypoglycaemic episodes, insulin glargine (HR 1.20 [95% CI 1.05, 1.36], p = 0.0059), insulin detemir (HR 1.18 [95% CI 1.04, 1.32], p = 0.0077) and insulin degludec (HR 1.04 [95% CI 0.81,1.33], p = 0.7706) seemed safer than human insulin (long-acting insulin HR 1.38 [95% CI 1.25, 1.52], p < 0.0001; combination insulins HR 1.84 [95% CI 1.65, 2.05], p < 0.0001) and, especially, sodium-glucose cotransporter 2 inhibitors (HR 0.43 [95% CI 0.33, 0.56], p < 0.0001), glucagon-like peptide 1 receptor agonists (HR 0.51 [95% CI 0.44, 0.58], p < 0.0001) and dipeptidyl peptidase 4 inhibitors (HR 0.44 [95% CI 0.38, 0.49], p < 0.0001) seemed safer than sulfonylureas (HR 2.27 [95% CI 2.18, 2.37], p < 0.0001).

Incidence rates of hypoglycaemic episodes leading to hospitalisation are declining in Denmark, and the advent of new treatment alternatives may play a significant role in this decline. From a safety perspective, these findings are important and should be considered by clinicians when assessing treatment options for patients.