Periodic limb movements on 713 consecutive video supported polysomnography VPSG

Abstract

Introduction Periodic limb movements during sleep (PLMs) can be an incidental finding, or they can be associated with several sleep disorders. They can even be a biological marker of diseases such as Restless Legs Syndrome (RLS). Materials and methods 713 adult patients underwent vPSG during 2012. We describe the epidemiology, clinical complaints, sleep diary data, symptoms, suspected diagnosis, associated diseases, vPSG measures, medication management and evolution of those (115) in which pathological PLMs index was reported. Results In 84/115 the study was done because of a clinical suspicion of sleep disorders: 57 sleep related breathing disorders (SRBD), 15 sleep disruption (insomnia ± daytime sleepiness), and 12 suspected parasomnias. 20/115 were conducted because of poor improvement after RLS treatment. Finally, 11/115 were to check PLMs as a supportive feature when essential criteria for RLS failed. Group data: 30 patients had a previous diagnosis of RLS (7 were not medicated and 12 were taking inappropriate drugs). 42 had never been asked about RLS symptoms. 57/115 had PLMs index higher than 15. Final diagnosis: Using vPSG data (mainly sleep disturbance and PLMs) and after an exhaustive clinical interview, 50 new RLS/PLMs diagnoses were made: In the suspected SRBD group 10/57 showed just RLS/PLMs and 14/57 showed an OSA as well, 11/15 had been sent to us because of insomnia, 9/12 from suspected parasomnia group fulfilled RLS criteria, and 6/11 showed PLMs as an associated feature when an RLS diagnosis was previously established just as possible, helping to resolve clinical uncertainty. In 4 patients, the previous diagnosis of RLS was changed by periodic limb movement disorder (PLMD). In 35 cases, the registered PLMs could be an incidental finding. Conclusion Although a simple questionnaire about RLS symptoms is a mandatory item to fill in before sending a patient to our sleep unit, when SRBD is suspected clinicians in our area overlooked it in a large percentage of cases (over 68%) Strong association was observed between PLMs index > 15 and severe RLS diagnosis, as well as for augmentation and PLMs index and/or PLM while awake (PLMw) data. We have found inappropriate therapy prescribed by both specialist and primary care doctors. Specialists working closely with a sleep unit, follow better treatment guidelines. When the specialist just suggests medication by therapeutic group with no concrete trade or generic name, clinicians in primary care do not follow practice guidelines. During the first months after the treatment, the patient should be closely followed up to check the effectiveness of the given pharmacological agents. That is not as common as it should be. Educational activities should still be done in primary care as well as in a specialized environment.