Epilepsy and risk of psychiatric disorders in later life: a population-based cohort study of 38,173 older men.

BACKGROUND

Mental disorders are frequent among individuals with epilepsy, but it is unclear if this association is causal in later life, particularly because of concurrent comorbidity. We investigated the association between epilepsy and major mental disorders in a large population-based cohort of older men.

METHODS

Participants were 38,173 community-dwelling men aged 65-85 years who were followed through linkage to administrative health data for over 20 years. ICD codes identified individuals with epilepsy, and depressive, anxiety, bipolar, psychotic and alcohol use disorders, as well as those with dementia, stroke, and traumatic brain injury. Competing risk analyses were conducted to account for death during follow-up.

RESULTS

At baseline, 505 men (1.3%) had epilepsy. Mental disorders were more prevalent among participants with than without epilepsy. Men with epilepsy had higher incidence rates of depressive, anxiety, psychotic, and alcohol use disorders, although the strength of these associations were attenuated after adjustment for neurological comorbidities and were no longer statistically significant when death was considered a competing risk. Age-matched analyses showed no significant associations between epilepsy and depressive, anxiety, bipolar, or psychotic disorders, although alcohol use disorder remained more frequent among men with epilepsy.

CONCLUSIONS

In this cohort of older men, epilepsy was associated with a higher prevalence but not incidence of mental disorders. These findings suggest that the psychiatric burden observed in older male adults with epilepsy most likely reflects shared pathology rather than causality, highlighting the importance of integrated neurological and mental health care.