Severe restless leg syndrome (RLS) is associated with an increased risk of stroke, according to research presented at SLEEP 2015: the Annual Meeting of the Associated Professional Sleep Societies in Seattle.
RLS has previously been associated with risk factors for stroke, including obesity, hypertension, and autonomic dysfunction. The researchers hypothesized that because people with RLS are more likely to develop stroke risk factors, they are also more likely to experience stroke.
The study included 72,916 female registered nurses from the Nurses’ Health Study II cohort. At baseline in 2005, the women were aged 41 to 58 and were free of diabetes, stroke, and pregnancy. The researchers used questionnaires based on International RLS Study Group criteria to collect information from each participant. The primary outcome was diagnosis of stroke (ischemic, hemorrhagic, and unknown etiology) over a 6-year follow-up period.
During the follow-up period, the researchers recorded 161 cases of stroke: 139 among participants with no RLS, 10 among participants with RLS <15 times per month, and 12 among participants with RLS ≥15 times per month. Participants who experienced RLS had an increased risk of stroke compared with people who did not experience RLS. Participants who experienced RLS <15 times per month had an adjusted hazard ratio of 1.37, and participants who experienced it ≥15 times per month had an adjusted hazard ratio of 2.07.
RLS was associated particularly strongly with ischemic stroke, with an adjusted hazard ratio of 3.52 in participants with RLS ≥15 times per month.
“We were surprised at the importance of taking into account RLS severity — it was only severe RLS, not milder RLS, that was associated with increased risk of stroke,” said researcher Xiang Gao, MD, PhD, of Pennsylvania State University in University Park, Pa., in a statement.
These results indicate that clinicians should ensure that their patients with RLS appropriately manage their cardiovascular risk factors in order to help prevent stroke.
- Wong JC et al. Abstract 0710. Presented at: SLEEP 2015: the Annual Meeting of the Associated Professional Sleep Societies. June 6-10, 2015; Seattle.