Men with nonapnea sleep disorders have a high risk of developing subsequent epilepsy: A nationwide population-based cohort study.

OBJECTIVE: This nationwide population-based cohort study evaluated the effects of nonapnea sleep disorders (NSDs) on the development of epilepsy.

METHODS: We identified 63,865 patients aged ≥20years, diagnosed with NSDs (ICD-9-CM: 307.4 or 780.5), and without coding for apnea-related sleep disorders (ICD-9-CM: 780.51, 780.53, or 780.57) during 2000-2003 as the NSD cohort. In addition, we enrolled a comparison cohort of 127,728 patients. We calculated the adjusted hazard ratio (aHR) for developing epilepsy (ICD-9-CM: 345) after adjustment for age, sex, comorbidities, and drug use. A Kaplan-Meier analysis was used to measure the cumulative incidence of epilepsy between the 2 groups until the end of 2011.

RESULTS: The cumulative incidence of epilepsy was significantly higher in the NSD cohort than in the comparison cohort. The aHR for developing epilepsy in the NSD cohort was 1.52 (95% CI=1.37-1.69). The risk of developing epilepsy was higher among males (aHR=1.41) than among females. The age-stratified effects of NSDs on developing epilepsy were the highest among patients aged ≥65years. When comorbidities and NSDs coexisted, the risk of epilepsy was specifically increased in patients having an NSD and stroke (aHR: 8.61, 95% CI: 7.43-9.98) in addition to brain tumors (aHR: 7.66, 95% CI: 5.06-11.6).

CONCLUSION: This study indicated that patients with NSDs have a higher risk of developing epilepsy and that the risk is much higher among men and older patients. These findings suggest that NSDs constitute a predisposing, possibly independent factor for developing subsequent epilepsy in adulthood.