Study objectives: Sleep disturbance is the primary clinical morbidity of restless legs syndrome (RLS). To date, sleep disturbance in RLS has been measured in (1) clinical samples with polysomnography (PSG) or (2) population-based samples by self-report. The objective of this study was to analyze sleep by PSG in a population-based sample with symptoms of RLS.
Design: Cross-sectional observational study.
Participants: 3433 older men and women.
Measurements and results: RLS was evaluated using an 8-item self-administered questionnaire based on NIH diagnostic criteria and required symptoms occurring > or = five times per month and associated with at least moderate distress. Health-related quality of life (HRQOL) was determined using the SF-36. Unattended, in-home PSG was performed. Data were assessed using general linear models with adjustment for demographic, health-related variables, and apnea-hypopnea index (AHI). Subjects with RLS had longer adjusted mean sleep latency (39.8 vs 26.4 min, P < 0.0001) and higher arousal index (20.1 vs 18.0, P = 0.0145) than those without RLS. Sleep latency increased progressively as the frequency of RLS symptoms increased from 5-15 days per month to 6-7 days per week. No differences in sleep stage percentages were observed between participants with and without RLS. Subjects with RLS also reported poorer HRQOL in all physical domains as well as in the Mental Health and Vitality domains.
Conclusions: These novel PSG data from a nonclinical, community-based sample of individuals with RLS document sleep disturbance in the home even in individuals with intermittent symptoms.