Type 1 diabetes may up epilepsy risk by three times: New study

People with type 1 diabetes have a three-times increased risk of developing epilepsy later in life, according to a new study.

Type 1 diabetes mellitus is one of the most common autoimmune disorders in children, with a 3% annual increase in the global incidence rate since the 1980s. In recent decades, the incidence of type 1 diabetes has increased in children and adolescents, particularly those aged younger than five years. Patients with diabetes are at increased risk of severe health problems and mortality.

For the study, researchers from China Medical University Children's Hospital in Taiwan evaluated the relationship between type 1 diabetes and epilepsy. Data from the Taiwan National Health Insurance Research Database was used to conduct retrospective analyses. The study cohort contained 2,568 patients with type 1 diabetes, each of whom was frequency-matched by sex, urbanisation of residence area and index year with ten control patients without type 1 diabetes.

Computer modelling was used to estimate the effects of type 1 diabetes on epilepsy risk. In patients with type 1 diabetes, the risk of developing epilepsy was significantly higher than that in patients without type 1 diabetes, researchers said. After adjustment for potential confounders, the type 1 diabetes cohort was 2.84 times more likely to develop epilepsy than the control cohort, they said.

"This result is consistent with those of previous studies in that epilepsy or seizures are observed in many autoimmune or inflammatory disorders and are linked to the primary disease, or secondary to pro-inflammatory processes," researchers said.

Immune abnormalities, brain lesions, genetic factors and metabolic abnormalities are all potential causes for the link between type 1 diabetes and epilepsy, they said. "In particular, both hyperglycaemia and hypoglycaemia commonly occur in elderly people with diabetes, and can alter the balance between the inhibition and excitation of neuronal networks and cause focal motor seizures," researchers said. "In addition, we found that younger age was associated with an increased risk of developing epilepsy," they said.

According to researchers, the results could provide evidence to facilitate the prognosis of children with type 1 diabetes. "Patients with type 1 diabetes are at an increased risk of developing epilepsy. Metabolic abnormalities of type 1 diabetes, such as hyperglycaemia and hypoglycaemia, may have a damaging effect on the central nervous system and be associated with significant long-term neurological consequences," they said.

The findings were published in the journal Diabetologia.