Patients who complain of restless leg syndrome (RLS) often have pain as one of the common symptoms of the disorder and they often seek medical treatment for relief of that pain, researchers reported here at SLEEP 2015, the 29th Annual Meeting of the Associated Professional Sleep Societies (APSS).
About 58% of adult patients were responders for both pain and International Restless Leg Score total score in a pooled analysis of 3 randomised controlled clinical trials, reported Gordon Irving, MD, University of Washington/Swedish Medical Center, Seattle, Washington.
The pooled trials (XPo52, XP053, and XP08) included 671 patients. The researchers observed that 24% of the patients did not respond to either decreases in pain or RLS, 13% responded just to pain, and 6% responded only to the restless leg total score.
Of that group, 366 reported mean pain scores of ≥4 on an 11-point numerical rating scale, indicating moderate pain levels.
The trials are part of a series of studies testing the effectiveness of gabapentin enarcarbil among people with mild to moderate RLS. Patients were either assigned to placebo, 600 mg of gabapentin enacarbil or 1200 mg of gabapentin enacarbil.
“Our findings suggest that pain is an important feature of RLS and impacts how adult patients rate the severity of their disease,” said Dr. Irving at his poster presentation on June 10. “This study highlights the importance of considering RLS as an underlying diagnosis when adult patients present solely with pain, particularly since adult patients with restless leg syndrome are often under diagnosed.”
For the patients who were diagnosed with mild-to-moderate RLS and mild-to moderate pain, the treatment emergent adverse events were mainly somnolence (17%), dizziness (11%), and headache (12%).
Dr. Irving said those adverse events are consistent with what has been observed for patients with just RLS treated with gabapentin enacarbil.
The patients in the study were on average 49 years, 60% were women, and 95% were white. Their mean years of living with RLS symptoms were more than 12 years. Only about one-third of the patients in the trial had been previously treated for RLS.