Periodic leg movement during sleep, which is a characteristic of restless legs syndrome (RLS), led to increased blood pressure among patients participating in a newly reported study from the University of Montreal.
Blood pressure increases were greatest among older patients with RLS, suggesting that these patients may be particularly vulnerable, says cardiologist Paola Lanfranchi, MD, MSc, one of the researchers in the study.
“We are learning more and more about the important role of sleep disturbances in heart disease,” she tells WebMD. “We have seen this with other sleep disorders. This study shows that we need to look closer at restless leg.”
BP Recorded During Sleep
Restless legs syndrome is considered both a neurological and sleep disorder because patients typically experience the worst symptoms when they lie down to sleep.
More than 80% of patients experience involuntary leg twitching or jerking movements during sleep that typically occur at intervals of 20 to 40 seconds.
As a result, patients may repeatedly awaken during the night and, like people with other sleep disorders, they many experience daytime fatigue, impaired memory, and concentration problems.
RLS patients have also been shown to have an increased risk for high blood pressure (hypertension) and heart disease in several previous studies, but it has not been clear if the sleep disorder contributed to the cardiovascular disease or visa versa, Lanfranchi says.
In an effort to answer this question, the University of Montreal researchers asked 10 patients with untreated RLS to spend the night in a sleep lab, where researchers monitored leg movements and blood pressure changes.
Lanfranchi and colleagues found that blood pressure rates linked to sleep-related periodic leg movement rose by an average of 22 points for the systolic reading (top number of a blood pressure reading) and 11 points for the diastolic reading (bottom number of blood pressure reading).