Prevalence and predictors of restless legs syndrome among patients having stable chronic obstructive pulmonary disease

Background: Patients having COPD share some factors, e.g., chronic hypoxemia, anemia of chronic disease and nicotine use, which are also the risk factors for RLS hence predispose them to experience RLS in higher then general population. There are limited studies with methodological constraints evaluating the prevalence and/or correlates of RLS among patients with COPD. Methods: Consecutive adult patients of either gender, having stable COPD as per GOLD guidelines 2021, were assessed for RLS using IRLSSG (2014) criteria (excluding RLS mimics) and the severity of RLS was determined in participants having RLS. Phenomenology of RLS, past medical history and laboratory parameters were gathered. Insomnia and depression were assessed using the insomnia severity index and PHQ-9, respectively. Results: Participants' (N = 210) mean age was 63.02 +/- 8.19 years, and 83.8% of subjects were men. 12.9% of participants were found to have RLS. Among those having RLS, nearly half (51.9%) had moderate symptoms, and 18.5% experienced severe symptoms. RLS was more prevalent among younger, females, those having severe COPD, participants having exacerbation of COPD in the previous year, lower post-bronchodilator FEV1, higher dyspnea and COPD assessment test score. Multivariate analysis showed that younger age, female gender, lower post-bronchodilator FEV1, lower FEV1/FVC ratio and higher serum creatinine increased the odds of having RLS. Depressive symptoms were more frequent in participants having RLS. Conclusions: The present study found that the prevalence of RLS among patients with stable COPD was higher than the general population. Female gender, younger age, higher airflow limitation and higher serum creatinine (though in the physiological range) increase the odds of having RLS. Stable patients with COPD having these characteristics must be screened for RLS.