Increased Disability in Pain Patients with Restless Legs Syndrome Per Grünwald Andersen1 , Eva McGehee1, Regitze Vrads2, Henrik Bjarke Vaegter1,3 1Pain Research Group, Pain Center South, University Hospital Odense, Denmark. Contact: per.g.andersen@rsyd.dk 2Pain Center South, University Hospital Odense, Denmark 3Department of Clinical Research, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark IASP 2016 Japan 1 Background Restless Legs Syndrome (RLS) is  characterized by throbbing, pulling, creeping, or other unpleasant sensations in the legs and an uncontrollable, and sometimes overwhelming, urge to move them. The prevalence of RLS in the general population is approximately 5% [1]. The prevalence of RLS is increased in patients with multiple pain sites [2], and in patients with fibromyalgia and somatoform pain disorders, the prevalence of RLS is above 30% [3,4]. The prevalence of RLS in patients with localized and regional chronic pain is currently unknown. Methods (cont.) Results (cont.) Results Results According to the diagnostic criteria described by The International Restless Legs Syndrome Study Group [5], patients were asked to reply with a ‘Yes’ or a ‘No’ to the following four questions: Urge to move the legs. The urge to move the legs worsen during periods of rest or inactivity such as lying down or sitting. The urge to move the legs and any accompanying unpleasant sensations are partially or totally relieved by movement . The urge to move the legs and any accompanying unpleasant sensations during rest or inactivity are worse in the evening or night than during the day. Chi-square test was used to analyse the distribution of RLS between groups (CWP, LBP, and MSPA). Univariate analyses with age as covariate were performed to assess potential differences in pain intensity, disability and quality of life between patients with or without RLS. RLS impact on clinical pain, disability and quality of life Age and disability was significantly increased in patients with RLS compared with patients without RLS (Fig. 2; P<0.05). No significant differences in pain intensity and quality of life were found between patients with and without RLS. Primary hyperalgesia on the left foot 2 Aim The primary aim of this study was to investigate the prevalence of (RLS) in patients with localized, regional and widespread chronic pain. Secondary aim was to compare clinical pain, disability and quality of life between patients with and without RLS. 4 Results Prevalence of RLS Thirty-five patients (29.7%) fullfilled the criteria for RLS by answering ‘YES’ to all 4 questions. No significant difference in the proportion of patients with RLS between CWP (12/34, 35%), LBP (11/24, 46%), and MSPA (12/25, 48%) were found (Fig. 2; Chi-square, P>0.7). Methods In total, 118 chronic pain patients (mean age: 47.3±13.4 years [range: 18-83]; 79 women) referred to a University Hospital Pain Clinic were included in this cross-sectional study. Prior to commencing treatment, patients completed the questionnaires on pain intensity, disability and health-related quality of life via an electronic software system (PainData, Denmark): Based on the clinical presentation, patients were divided into three groups (see Fig. 1); A low back pain group (LBP): primary pain in the lower back without pain referral below the knees (N = 35). Multiple spinal pain areas (MSPA): pain in the more than one spinal area, including primary pain in the lower back (N = 37). Chronic widespread pain (CWP: spinal pain + pain in all four extremities; N = 46). 3 Fig. 3: Mean (+SEM) pain disability scores between patients with and without RLS. Significant difference between groups (*,P<0.05). 5 Conclusions Restless Legs Syndrome has a high prevalence in patients with chronic pain across different chronic pain conditions. Patients with RLS demonstrate higher levels of disability compared with patients without RLS. Early assessment, diagnosis, and management of RLS may reduce disability and improve reatment outcomes References Ohayon MM, O’Hara R, Vitiell NV. Epidemiology of restless legs syndrome: A synthesis of the literature. Sleep Med Rev, 2012;16:283-95. Hoogwout SJ, Paananen MV, Smith AJ et al. Musculoskeletal pain is associated with restless les syndrome in young adults. BMC Musculoskeletal Disord, 2015;16:294. Aigner M, Prause W, Freidl M, Weiss M, Izadi S, Bach M, Saletu B. High prevalence of restless legs syndrome in somatoform pain disorder. Eur Arch Psychiatri Clin Neurosci, 2007;257:54-7. Viola-Saltzman M, Watson NF, Bogart A, Goldberg J, Buchwald D. High prevalence of Restless Legs Syndrome among Patients with Fibromyalgia: A controlled Crosse-Sectional Study. J Clin Sleep Med, 2010;6:423-27. Allen RP, Picchietti DL, Garcia-Borreguero D et al. Restless legs syndrome/Willis-Ekbom disease diagnostic criteria: upadated International Restless Legs Syndrome Study Group (IRLSSG) consensus criteria – history, rationale, description, and significance. Sleep Med, 2014;15:860-873. Fig. 2: Proportion of patients with CWP, LBP and MPSA fulfilling the criteria for RLS. Fig. 1: Pain distributions in the 3 groups.