Introduction: Sleep duration has been regarded as a potential risk factor for cardiovascular disease and stroke. Short sleep duration is linked with higher stroke incidence, and mortality. Moreover, and paradoxically, long sleep duration is also reported to be positively associated with stroke incidence. However, the impact of sleep duration on the intracerebral hemorrhage (ICH) risk remains unclear.
Hypothesis: We assessed the relationship between sleep duration and the risk of ICH.
Methods: We performed a nationwide, multicenter matched case-control study to investigate the risk factors for hemorrhagic stroke, using patients from 33 hospitals in Korea. We enrolled a total of 490 patients with ICH and 980 age- and sex-matched controls. We obtained information regarding sleep, sociodemographic factors, lifestyle, and medical history before ICH onset, using qualified structured questionnaires. Sleep duration was categorized as ≤5, 6, 7, 8, and ≥9 hours. We chose sleep duration of 7 h as the reference duration.
Results: The included patients were mostly male (58.2%) with a mean age of 57 years. The number of subjects with long sleep duration, more than 8 h, was significantly greater in the ICH group than in the control group (≥8 h, 30.4% vs. 22.6%, P = 0.002). Compared to 7 h, long sleep duration participants tended to be older, be more hypertensive, and be more likely to have blue collar jobs, lower education levels, and poorer marital status (i.e., unmarried or divorced/separated). After controlling for confounding factors, we found that longer sleep duration was independently associated with the risk of ICH in a dose-response manner (8 h: Odds ratio, 1.44; confidence interval, 1.01-2.07; ≥9 h: Odds ratio, 2.60; confidence interval, 1.50–4.49).
Conclusions: In conclusion, our study suggested that long sleep duration is positively related to ICH risk in a dose-dependent manner. In this context, our data might suggest that sleep duration is a modifiable risk factor for ICH.