Periodic limb movement disorder (PLMD) and restless legs syndrome (RLS) are two sleep
disorders characterized by abnormal leg movements and are responsible for deterioration
in sleep quality. However, the prevalence of these disorders is not well known in
the general population. This study aims to document the prevalence of RLS and PLMD
in the general population and to identify factors associated with these conditions.
Cross-sectional studies were performed in the UK, Germany, Italy, Portugal and Spain.
Overall, 18,980 subjects aged 15 to 100 years old representative of the general population
of these five European countries underwent telephone interviews with the Sleep-EVAL
system. A section of the questionnaire assessed leg symptoms during sleep. The diagnoses
of PLMD and RLS were based on the minimal criteria provided by the International Classification
of Sleep Disorders.
The prevalence of PLMD was 3.9% and RLS was 5.5%. RLS and PLMD were higher in women
than in men. The prevalence of RLS significantly increased with age. In multivariate
models, being a woman, the presence of musculoskeletal disease, heart disease, obstructive
sleep apnea syndrome, cataplexy, doing physical activities close to bedtime and the
presence of a mental disorder were significantly associated with both disorders. Factors
specific to PLMD were: being a shift or night worker, snoring, daily coffee intake,
use of hypnotics and stress. Factors solely associated with RLS were: advanced age,
obesity, hypertension, loud snoring, drinking at least three alcoholic beverages per
day, smoking more than 20 cigarettes per day and use of SSRI.
PLMD and RLS are prevalent in the general population. Both conditions are associated
with several physical and mental disorders and may negatively impact sleep. Greater
recognition of these sleep disorders is needed.