Vascular risk factors such as diabetes, hypercholesterolemia, body mass index, smoking status, and exercise were associated with the prevalence of restless legs syndrome in 12% of women aged older than 45 years, although a link was not found with cardiovascular events such as stroke or myocardial infarction, according to a study.
Previous studies have indicated that an unhealthy vascular profile might be the mechanism linking restless legs syndrome with cardiovascular disease (CVD) in women, but the data are inconsistent.
Dr. Tobias Kurth
Dr. Tobias Kurth of Inserm Research Center for Epidemiology and Biostatistics and the University of Bordeaux, France, and his colleagues, sought a more definitive connection in a cross-sectional study of 30,262 women who participated in the Women’s Health Study (WHS). In the 9th year of the study, validated criteria from the International Restless Legs Study Group were added to the follow-up survey.
Dr. Kurth and his investigators applied age-adjusted and multivariable-adjusted logistic regression models to the complete data provided by 30,262 respondents (mean age 63.6 years) to evaluate the association between restless legs syndrome and independent vascular risk factors such as diabetes, hypertension, hypercholesterolemia, BMI, alcohol, smoking, exercise, and family history of MI. They adjusted for age, aspirin use, postmenopausal status, postmenopausal hormone use, and history of oral contraceptive use (Am. J. Med. 2013;126:220-7 [doi:10.1016/j.amjmed.2012.06.040]).
Patient-reported data on cardiovascular events were confirmed by medical record review.
A total of 3,634 (12%) of the women had restless legs syndrome. Women with several vascular risk factors were at greater odds of having restless legs syndrome, BMI greater than 35 (OR 1.35), diabetes (OR 1.19), hypercholesterolemia (OR 1.17), smoking 15 or more cigarettes per day (OR 1.41), and exercise less than four times per week (OR 0.84). Those who underwent coronary revascularization had a multivariable-adjusted OR of 1.39 for restless legs syndrome.
Noting that genetics, endocrine disturbances, and lifestyle-related comorbidities such as smoking have been theorized as mechanisms of restless legs syndrome, the authors wrote that "the cross-sectional design of our study and previous reports does not allow drawing conclusions regarding direction and causality of the association."
Furthermore, while reports cited by the investigators found similar prevalence rates between restless legs syndrome and vascular risk, the authors concluded they "could not confirm results from previous studies indicating an association between prevalent cardiovascular disease and restless legs syndrome."
The study was funded by the National Heart, Lung, and Blood Institute. The Women’s Health Study was underwritten by NHBLI and the National Cancer Institute. The investigators listed multiple financial conflicts of interest regarding restless legs syndrome research and treatments.