Physical and mental health comorbidities of epilepsy: population-based cross-sectional analysis of 1.5 million people in Scotland

Purpose: To measure the prevalence of physical and mental health comorbidities in people with epilepsy in a large population cohort, and to examine the prevalence of depression accounting for other physical comorbidity.

Methods: Population-based, cross-sectional descriptive epidemiology analysis of primary care electronic records for 1,510,742 people aged 14+ years, examining the prevalence of 39 comorbidities.

Results: 12,720 people with epilepsy were identified (prevalence 8.4/1000 population, 95% CI 8.3–8.5). Physical and mental health comorbidity was more common with epilepsy (mean of an additional 1.02 physical conditions difference, 95% CI 0.99–1.06). 69.9% of people with epilepsy had one or more comorbid health conditions and 18.6% had four or more, compared to 46.9% and 9.0% of people without epilepsy. Depression was present in 16.3% of people with epilepsy compared to 9.5% of those without (adjusted OR 1.57, 95% CI 1.49–1.65). The prevalence of comorbid depression in epilepsy increased as the number of physical comorbidities increased (OR 5.82, 95% CI 4.90–6.91 for 4+ physical comorbidities vs none) and with increasing deprivation, similar to the patterns observed in other common physical conditions.

Conclusion: People with epilepsy have higher rates of both physical and mental health comorbidity than people without even after adjustment for age, gender and levels of deprivation. Depression is more common than in the general population but the prevalence is similar to other physical health conditions, and is strongly associated with the total burden of physical conditions. This study highlights the complexity in caring for people with epilepsy.