Epidemiology of restless legs syndrome: a synthesis of the literature

Abstract

Restless legs syndrome (RLS) has gained considerable attention in the recent years: nearly 50 community-based studies have been published in the last decade around the world. The development of strict diagnostic criteria in 1995 and their revision in 2003 helped to stimulate research interest on this syndrome. In community-based surveys, RLS has been studied as: 1) a symptom only, 2) a set of symptoms meeting minimal diagnostic criteria of the international restless legs syndrome study group (IRLSSG), 3) meeting minimal criteria accompanied with a specific frequency and/or severity, and 4) a differential diagnosis. In the first case, prevalence estimates in the general adult population ranged from 9.4% to 15%. In the second case, prevalence ranged from 3.9% to 14.3%. When frequency/severity is added, prevalence ranged from 2.2% to 7.9% and when differential diagnosis is applied prevalence estimates are between 1.9% and 4.6%. In all instances, RLS prevalence is higher in women than in men. It also increases with age in European and North American countries but not in Asian countries. Symptoms of anxiety and depression have been consistently associated with RLS. Overall, individuals with RLS have a poorer health than non-RLS but evidence for specific disease associations is mixed. Future epidemiological studies should focus on systematically adding frequency and severity in the definition of the syndrome in order to minimize the inclusion of cases mimicking RLS.

Figure 1

Changes in RLS prevalence rates in North America and Europe general population according to used definitions *Prevalence rates for differential diagnosis came from primary care samples. Prevalence estimates are based on samples including participants from 18 to >= 65 years.

Figure 2a

Prevalence of RLS in men – North America and Europe Included 12 studies that had provided prevalence by age groups for men. These studies are based on minimal IRLSSG criteria. A total of 23,282 men aged >=18 are included in the scatter plot.

Figure 2b

Prevalence of RLS in men – Asia Included 5 studies that had provided prevalence by age groups for men. These studies are based on minimal IRLSSG criteria. A total of 8,081 men aged >=18 are included in the scatter plot.

Figure 2c

Prevalence of RLS in women – North America and Europe Included 12 studies that had provided prevalence by age groups for women. These studies are based on minimal IRLSSG criteria. A total of 26,150 women aged >=18 are included in the scatter plot.

Figure 2d

Prevalence of RLS in women – Asia Included 6 studies that had provided prevalence by age groups for women. These studies are based on minimal IRLSSG criteria. A total of 11,253 women aged >=18 are included in the scatter plot.