The frequency and clinical associations of restless legs syndrome in australian patients with fibromyalgia.

Abstract

Aim: Fibromyalgia is a common disorder characterized by musculoskeletal pain, fatigue, unrefreshing sleep and cognitive problems thought to reflect the underlying pathophysiological process of central sensitization. Fibromyalgia is often associated with other clinical syndromes such as Irritable Bowel Syndrome (IBS), headache and temporomandibular joint disorder that are also linked to central sensitization. Restless Legs Syndrome (RLS) is found with increased frequency in fibromyalgia1 however the pathophysiology of RLS relates to an alteration in dopamine neurotransmission rather than central sensitisation. Our aim was to investigate the prevalence of RLS in an Australian fibromyalgia population, and identify clinical features associated with RLS in the Monash Fibromyalgia Cohort. Method(s): Consecutive fibromyalgia patients seen in a public outpatient clinic were questioned regarding the features of RLS. Demographic and comorbidity information, a tender-point count and BMI were recorded. A Fibromyalgia Impact Questionnaire (FIQ), and the Widespread Pain Index and Symptom Severity Score were calculated. Result(s): 288 patients from the Monash Fibromyalgia Cohort were included (female 90.6%, mean age 46 years). 195 patients (67.7%) fulfilled RLS criteria. Compared to fibromyalgia patients without RLS, fibromyalgia patients with RLS showed a higher rate of IBS (p = 0.03), higher tender point counts (p = 0.02) and reported more wide-spread pain (p = 0.02). They also reported more severe levels of pain (p = 0.03), worse sleep disturbance (p = 0.006) and higher FIQ scores (p = 0.031). No group differences were observed for demographic variables, fatigue or physical function. Conclusion(s): RLS frequently coexists in patients with fibromyalgia. Patients with both fibromyalgia and RLS reported more severe fibromyalgia illness, particularly pain, tenderness and sleep disturbance. Dopamine agonists, such as pramipexole, are useful in RLS and may also improve symptoms of fibromyalgia2. Further exploration of dopaminergic mechanisms in fibromyalgia is warranted.