Prevalence of restless legs syndrome among adults in Iceland and Sweden: Lung function, comorbidity, ferritin, biomarkers and quality of life
ABSTRACT This study investigates the prevalence and the association between restless legs syndrome (RLS) and a large variety of health variables in two well-characterized random samples from the general population in Reykjavik, Iceland, and Uppsala, Sweden.
Using the national registries of inhabitants, a random sample from adults aged 40 and over living in Reykjavík, Iceland (n=939), and Uppsala, Sweden (n=998), were invited to participate in a study on the prevalence of COPD (response rate 81.1% and 62.2%). In addition, the participants were asked to answer the following questionnaires: International RLS Rating Scale, Short Form-12, the Epworth Sleepiness Scale, and questions about sleep, gastroeosophageal reflux, diabetes and hypertension, as well as pharmacological treatment. Interleukin-6 (IL-6), C-reactive protein (CRP) and ferritin were measured in serum.
RLS was more commonly reported in Reykjavik (18.3%) than in Uppsala (11.5%). Icelandic women reported RLS almost twice as often as Swedish women (24.4 vs. 13.9% p=0.001), but there was no difference in prevalence of RLS between Icelandic and Swedish men. RLS was strongly associated with sleep disturbances and excessive daytime sleepiness. Subjects with RLS were more likely to be ex- and current smokers than subjects without RLS (p<0.001). Respiratory symptoms and airway obstruction were more prevalent among those reporting RLS and they also estimated their physical quality of life lower than those without RLS (p<0.001). RLS was not associated with symptoms of the metabolic syndrome like hypertension, obesity, markers of systemic inflammation (IL-6 and CRP) or cardiovascular diseases. Ferritin levels were significantly lower in RLS participants (p=0.0002), but not (p=0.07) after adjustment for center, age, sex and smoking history.
Restless legs syndrome was twice as common among Icelandic women compared to Swedish women. No such difference was seen for men. RLS was strongly associated with smoking and respiratory symptoms, decreased lung function, sleep disturbances, excessive daytime sleepiness, and physical aspects of life quality. RLS was not associated with markers of the metabolic syndrome like hypertension, obesity, cardiovascular diseases or biomarkers of systemic inflammation.
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ABSTRACT: In recent years, there have been a number of advances in the field of restless legs syndrome (RLS) or Willis-Ekbom disease (WED). Here, we review recent studies pertaining to the diagnosis and clinical features, pathogenesis, and treatment of RLS/WED.
Article: Sleep Disorders in Pregnancy[Show abstract] [Hide abstract]
ABSTRACT: Sleep disturbances are common in pregnancy and may be influenced by a multitude of factors. Pregnancy physiology may predispose to sleep disruption but may also result in worsening of some underlying sleep disorders, and the de novo development of others. Apart from sleep disordered breathing, the impact of sleep disorders on pregnancy, fetal, and neonatal outcomes is poorly understood. In this article, we review the literature and discuss available data pertaining to the most common sleep disorders in perinatal women. These include restless legs syndrome, insomnia, circadian pattern disturbances, narcolepsy, and sleep-disordered breathing.Clinics in Chest Medicine 09/2014; DOI:10.1016/j.ccm.2014.06.012 · 2.17 Impact Factor
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ABSTRACT: Restless legs syndrome (RLS), also known as Willis-Ekbom Disease (WED), is a sensorimotor disorder for which the exact pathophysiology remains unclear. Brain iron insufficiency and altered dopaminergic function appear to play important roles in the etiology of the disorder. This concept is based partly on extensive research studies using CSF, autopsy material, and brain imaging indicating reduce regional brain iron and on the clinical efficacy of dopamine receptor agonists for alleviating RLS symptoms. Finding causal relations, linking low brain iron to altered dopaminergic function in RLS, has required however the use of animal models. These models have provided insights into how alterations in brain iron homeostasis and dopaminergic system may be involved in RLS. The results of animal models of RLS and biochemical, postmortem, and imaging studies in patients with the disease suggest that disruptions in brain iron-trafficking lead to disturbances in striatal dopamine neurotransmission for at least some patients with RLS. This review examines the data supporting an iron deficiency–dopamine metabolic theory of RLS by relating the results from animal model investigations of the influence of brain iron deficiency on dopaminergic systems to data from clinical studies in patients with RLS.Sleep Medicine 11/2014; 15(11). DOI:10.1016/j.sleep.2014.05.009 · 3.10 Impact Factor