It is also very current, having been conducted in late 2004, while the data from the Third National Health and Nutrition Examination Survey were collected more than a decade ago. The age ranges and definitions of geographic areas covered by each study are different. Yet, the findings are striking, since both anemia and RLS symptoms appear to be more prevalent in the south. While this association can be considered hypothesis-generating at best, it supports the biological basis of iron deficiency as a factor in the pathogenesis RLS. We found a tendency for the endorsement of RLS symptoms to increase with age until the age of 65 years, as has been reported by others,” and we noted a trend toward increased prevalence in women compared with men. We also confirmed the association between RLS symptoms and both cigarette smoking and being overweight. There was a strong association between physical and mental health problems and RLS symptoms, as has consistently been reported by others.’ this
Our findings both differ from and support the results from the RLS Epidemiology, Symptoms, and Treatment (REST) study, which reported a 5% prevalence of weekly symptoms and a 2.7% prevalence of at least twice weekly symptoms that were moderately or severely distressing. The REST study involved 15,391 completed questionnaires from several western European countries and the United States. The REST study employed six questions relative to RLS (in addition to prescreening and postscreening questions), so the resulting RLS prevalence estimate is, not unexpectedly, more conservative. On the other hand, the prevalence of about 10% that we found in the current study is very similar to that reported in other large-scale population studies.