OBJECTIVE: Restless legs syndrome (RLS) is a common sleep disorder in which patients feel unpleasent leg sensations and urge to move the legs during rest, especially at night, and symptoms are improved by leg movement. Prior studies analyzing the associations between cardiovascular disease and restless legs syndrome has shown controversial results. The goal of the study was to estimate the relationship between restless legs syndrome and slow coronary flow (SCF).
METHODS: The present study was cross-sectional and observational and consists of 176 individuals who underwent coronary angiography and had angiographically normal coronary arteries of varying coronary flow rates. The study included 86 patients with isolated SCF and 90 control participants with normal coronary flow (NCF). RLS was assessed the day after the coronry flow was evaluated, using a self-administered questionnaire based on the International Restless Legs Study Group criteria. The following question was asked: "Do you have unpleasant leg sensations (like crawling, paraesthesia, or pain) combined with motor restlessness and an urge to move?" The possible responses were as follows: no, less than once/month, 2-4 times/month, 5-14 times/month, and 15 or more times per month. Those who answered that they had these feelings were asked the following two more questions: 1) "Do these symptoms occur only at rest and does moving improve them?" and 2) "Are these symptoms worsen in the evening/at night compared with the morning?" RLS is considered to be probable if the participant has answered "yes" for all three of the above questions, and has a frequency of ≥5 times/month. Student's t-test, Mann-Whitney U test, multiple logistic regression analysis were used for statistical analysis.
RESULTS: The prevalence of restless legs syndrome was 48 (27%) and increased significantly with age. Patients with SCF have more likely had RLS than the control group (p<0.001). The age-adjusted prevalence odds of SCF were 3.11 times higher (95% CI: 1.54-6.29; P<0.001) among patients with RLS symptoms. Significant associations between RLS and SCF did not materially change after further adjustment for other potential covariates, such as sex, BMI, BMI squared, smoking.
CONCLUSION: Our study concluded that there is a strong link between SCF and RLS.
