2. Institute for Community Medicine, University of Greifswald, Germany.
3. Department of Neurology, Inselspital, Universitätsspital Bern, Bern, Switzerland.
4. Robert Koch-Institute, Berlin, Germany.
We report results from three independently conducted studies on the prevalence of cancer in restless legs syndrome (RLS) cases and non RLS cases. Already in 1955 Ekbom observed RLS in patients with subsequently detected cancer. Since then only three case reports and one article assessed the relationship between RLS and cancer patients undergoing chemotherapy. The observed proportion of RLS in these cancer patients (18.3%) was about twice as high as in general population studies. Two of our studies were general population based studies (Dortmund Health Study (DHS); Study of Health in Pomerania (SHIP)) and one was performed among members of the German and Swiss RLS patient organizations (Course of Restless Legs Syndrome-Study (COR-S)). Additionally we used data from the population based, regional cancer registry of the Muenster district for comparisons. Our data show that in all three studies the prevalence of cancer was higher in RLS cases than in non cases for both genders. In two of the studies the increased risk was in part explained by age. The data of the COR-Study revealed a statistically significant higher risk for cancer in RLS subjects compared to the population based data of the regional cancer registry of Muenster. Our results suggest a higher proportion of cancer among RLS cases compared to individuals without RLS. Given an RLS prevalence of about 5 to 10 percent in the general population, a need to rule out cancer in patients with a new onset of RLS, especially among the elderly patients is important.
Keywords: Restless legs syndrome, cancer, prevalence, epidemiology