Restless legs syndrome in an appalachian primary care population: prevalence, demographic and lifestyle correlates, and burden

The Relationship between Serum Selenium Levels and Restless Leg Syndrome in Chronic Kidney Disease Patients

Background and Objectives: Chronic kidney disease (CKD) is a global public health issue with rising incidence linked to substantial morbidity and mortality. Selenium, an antioxidant trace element, has been linked to low serum levels in end-stage renal disease. Restless Leg Syndrome (RLS), a sleep disorder, is prevalent in CKD patients and significantly impacts their quality of life. The objective of this study was to examine the correlation between serum selenium levels and the prevalence of restless leg syndrome in individuals with chronic kidney disease. Materials and Methods: Forty-six CKD patients undergoing serum selenium level assessments between 1 January 2020 and 28 February 2022, at the Hitit University Faculty of Medicine Department of Nephrology Outpatient Clinic or Hemodialysis Unit, were included. Patients over 18 years of age with no history of hematological or oncological diseases or acute or chronic inflammatory conditions were included in the study groups. Patients taking selenium supplements were excluded. Demographic data, comorbidities, and laboratory values were collected, and RLS presence and severity were evaluated. Statistical analyses include descriptive statistics, correlation analysis, the Mann-Whitney U test, Student's t test, and Chi-square test. Results: Among the 46 patients, 16 (34.78%) had RLS symptoms. The patient group included 34.78% predialysis, 34.78% peritoneal dialysis, and 30.44% hemodialysis patients, with a median age of 47.98 years. There was no difference in age, gender, and Charlson comorbidity between patients with or without RLS (p = 0.881, p = 0.702, p = 0.650). RLS prevalence varied across CKD subgroups, with hemodialysis patients having a higher prevalence (p = 0.036). Clinical parameters such as blood urea nitrogen, creatinine, calcium, phosphorus, platelet counts, and parathyroid hormone levels exhibited significant differences between patients with and without RLS (p < 0.05). Serum selenium levels were not significantly different between patients with and without RLS (p = 0.327). Conclusions: With an increased comorbidity burden, CKD poses a significant healthcare challenge. When accompanied by RLS, this burden can be debilitating. The difference in CKD stages between groups has shed light on a critical determinant of RLS in this population, emphasizing the role of the chronic kidney disease stage. In our study, serum selenium levels were not associated with the presence and severity of RLS. However, prospective studies with larger numbers of participants are needed to draw a definitive conclusion.

Socioeconomic status and sleep health: a narrative synthesis of 3 decades of empirical research

STUDY OBJECTIVES

This review aims to assess the association between socioeconomic status (SES) and sleep health in the general population and the mediating effects of lifestyle and mental and physical health in this relationship.

METHODS

Observational studies testing the independent association between objective or subjective SES indicators and behavioral/physiological or clinical sleep health variables in the general population were included. PubMed/MEDLINE was searched for reports published from January 1990 to December 2019. The direction of effect was used as the primary effect measure, testing the hypothesis that low SES is associated with poor sleep health outcomes. Results are presented in the form of direction effect plots and synthesized as binomial proportions.

RESULTS

Overall, 336 studies were identified. A high proportion of effects at the expected direction was noted for measures of sleep continuity (100% for sleep latency, 50-100% for awakenings, 66.7-100% for sleep efficiency), symptoms of disturbed sleep (75-94.1% for insomnia, 66.7-100% for sleep-disordered breathing, 60-100% for hypersomnia), and general sleep satisfaction (62.5-100%), while the effect on sleep duration was inconsistent and depended on the specific SES variable (92.3% for subjective SES, 31.7% for employment status). Lifestyle habits, chronic illnesses, and psychological factors were identified as key mediators of the SES-sleep relationship.

CONCLUSIONS

Unhealthy behaviors, increased stress levels, and limited access to health care in low-SES individuals may explain the SES-sleep health gradient. However, the cross-sectional design of most studies and the high heterogeneity in employed measures of SES and sleep limit the quality of evidence. Further research is warranted due to important implications for health issues and policy changes.

CITATION

Papadopoulos D, Etindele Sosso FA. Socioeconomic status and sleep health: a narrative synthesis of 3 decades of empirical research. J Clin Sleep Med. 2023;19(3):605-620.

Sex differences in the effects of sleep disorders on cognitive dysfunction

Sleep is an essential physiological function that sustains human life. Sleep disorders involve problems with the quality, duration, and abnormal behaviour of sleep. Insomnia is the most common sleep disorder, followed by sleep-disordered breathing (SDB). Sleep disorders often occur along with medical conditions or other mental health conditions. Of particular interest to researchers is the role of sleep disorders in cognitive dysfunction. Sleep disorder is a risk factor for cognitive dysfunction, yet the exact pathogenesis is still far from agreement. Little is known about how sex differences influence the changes in cognitive functions caused by sleep disorders. This narrative review examines how sleep disorders might affect cognitive impairment, and then explores the sex-specific consequences of sleep disorders as a risk factor for dementia and the potential underlying mechanisms. Some insights on the direction of further research are also presented.

Sleep Quality and Nocturnal Symptoms in a Community-Based COPD Cohort

Small studies have suggested that patients with chronic obstructive pulmonary disease (COPD) have poor sleep quality. Our aim was to examine the prevalence of subjective sleep-related complaints and predictors of poor sleep quality in a large community-based COPD cohort. We analyzed cross-sectional data on sleep questionnaire responses from the Canadian Cohort of Obstructive Lung Disease (CanCOLD) study, a population-based, prospective longitudinal cohort study across Canada. The cohort comprises a COPD group and two matched non-COPD (never-smokers and ever-smokers) groups. Sleep-related symptoms were assessed using questionnaires including Pittsburgh Sleep Quality Index (PSQI). A total score of PSQI > 5 is indicative of poor sleep quality. Health-related quality of life measures and the presence of mood disturbance were assessed using Short Form-36™ Health Survey (SF-36) multi-item questionnaires and Hospital Anxiety and Depression Scale (HADS), respectively. Predictors of poor sleep quality were analyzed using multivariable logistic regression analysis. Of the 1123 subjects, 263 were healthy controls, 323 at-risk controls, and 537 had COPD (297 had mild, 240 with moderate to severe disease). The mean PSQI score was not significantly different between groups. COPD patients with poor sleep quality had lower diffusion capacity, higher HADS anxiety and depression scores and lower SF-36 mental and physical component summary scores than COPD patients classified as good sleepers. The presence of restless legs and obstructive sleep apnea symptoms, waist circumference, predicted diffusion capacity and HADS anxiety and depression scores were identified as independent predictors of poor sleep quality.

Impact of Sleep Disorder as a Risk Factor for Dementia in Men and Women

Sleep is an essential physiological process, especially for proper brain function through the formation of new pathways and processing information and cognition. Therefore, when sleep is insufficient, this can result in pathophysiologic conditions. Sleep deficiency is a risk factor for various conditions, including dementia, diabetes, and obesity. Recent studies have shown that there are differences in the prevalence of sleep disorders between genders. Insomnia, the most common type of sleep disorder, has been reported to have a higher incidence in females than in males. However, sex/gender differences in other sleep disorder subtypes are not thoroughly understood. Currently, increasing evidence suggests that gender issues should be considered important when prescribing medicine. Therefore, an investigation of the gender-dependent differences in sleep disorders is required. In this review, we first describe sex/gender differences not only in the prevalence of sleep disorders by category but in the efficacy of sleep medications. In addition, we summarize sex/gender differences in the impact of sleep disorders on incident dementia. This may help understand gender-dependent pathogenesis of sleep disorders and develop therapeutic strategies in men and women.

Clinical Study of Restless Leg Syndrome Accompanied by Psychological Symptoms Induced by High-Dose Treatment With Madopar

Objectives: Some neurological disorders demonstrate indistinguishable psychological symptoms at an early stage, especially when accompanied by jitters similar to those in Parkinson's disease. During dopamine replacement therapy, some patients display restless leg syndrome (RLS)-like symptoms. Therefore, we aimed to analyze treatment strategies and the prognosis of RLS caused by high-dose Madopar. Methods: Nine patients who were misdiagnosed with Parkinson's disease, taking a high dose of Madopar, and showed symptoms of anxiety, depression, and somatization were recruited. Clinical data were collected, and strategies of treatment and prognosis were analyzed. Results: Seven patients demonstrated varying degrees of anxiety and depression, and the other two cases were misdiagnosed as Parkinson's disease. During Madopar treatment, patients gradually showed aggravated symptoms, including swelling, numbness, pain, and other sensory abnormalities in both lower extremities, which spread to both upper extremities in a few patients. Among the seven patients, symptoms of anxiety, depression, insomnia, and somatization significantly worsened during the observation period. The average time from taking Madopar to the appearance of RLS was 2.6 ± 0.6 months, the average time to clinical diagnosis was 18.17 ± 9.40 months, and the average dosage of Madopar was 1.44 ± 0.21 g per day. Gradually reducing the Madopar dosage and administering a small dose of long-acting dopamine preparation greatly alleviated the symptoms after 3 months. Conclusion: A high dose of Madopar can cause RLS-like symptoms accompanied by anxiety, depression, insomnia, and other mental health symptoms. These symptoms should be more closely monitored by clinicians.

Neuroimaging of Sleep Disturbances in Movement Disorders

Sleep dysfunction is recognized as a distinct clinical manifestation in movement disorders, often reported early on in the disease course. Excessive daytime sleepiness, rapid eye movement sleep behavior disorder and restless leg syndrome, amidst several others, are common sleep disturbances that often result in significant morbidity. In this article, we review the spectrum of sleep abnormalities across atypical Parkinsonian disorders including multiple system atrophy (MSA), progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS), as well as Parkinson's disease (PD) and Huntington's disease (HD). We also explore the current concepts on the neurobiological underpinnings of sleep disorders, including the role of dopaminergic and non-dopaminergic pathways, by evaluating the molecular, structural and functional neuroimaging evidence based on several novel techniques including magnetic resonance imaging (MRI), functional magnetic resonance imaging (fMRI), diffusion tensor imaging (DTI), single-photon emission computed tomography (SPECT) and positron emission tomography (PET). Based on the current state of research, we suggest that neuroimaging is an invaluable tool for assessing structural and functional correlates of sleep disturbances, harboring the ability to shed light on the sleep problems attached to the limited treatment options available today. As our understanding of the pathophysiology of sleep and wake disruption heightens, novel therapeutic approaches are certain to transpire.

Occupational Health and Sleep Issues in Underserved Populations

Sleep disorders and occupational hazards, injuries, and illnesses impact an individual's overall health. In the United States, substantial racial, ethnic, and socioeconomic disparities exist in sleep and occupational health. Primary care physicians working in underserved communities should be aware of this disparity and target these higher-risk populations for focused evaluation and intervention.

Restless Legs Syndrome in a Nigerian Elderly Population

STUDY OBJECTIVES

The prevalence of restless legs syndrome (RLS) is highest in the elderly in Caucasian populations; the prevalence of RLS in elderly Africans is not known. This study aimed at determining the frequency and associations of RLS in a Nigerian elderly population.

METHODS

The study population comprised of 633 consecutive elderly individuals aged 65-105 years attending the general outpatient clinic of the State Hospital, Ilesa, for minor complaints and routine check-up. The diagnosis of RLS was made using the 2003 minimal criteria of the International Restless Legs Syndrome Study Group. Relevant sociodemographic and clinical data, including sleep duration, were also obtained.

RESULTS

Restless legs syndrome was found in 3.5% of the study population with a male-female ratio of 2:1. There was no significant age (p = 0.427) or gender (p = 0.178) influence on the prevalence of RLS except in the 75- to 84-year age group where there was significant male preponderance (p = 0.044). A strong independent association between RLS and sleep duration (OR, 3.229; 95% CI, 1.283-8.486; p = 0.013) and past history of head injury (OR, 4.691; 95% CI, 1.750-12.577; p = 0.002) was found.

CONCLUSIONS

Our finding support previous reports of a possible lower prevalence of RLS in Africans. Restless legs syndrome independently increases the odds of habitual sleep curtailment in elderly individuals. Head injury may be a risk factor for future RLS; this requires further investigation as indirect evidence for a possible link between RLS and traumatic brain injury exists.

The Relationship of Restless Legs Syndrome to History of Pregnancy-Induced Hypertension

BACKGROUND

Restless legs syndrome (RLS), a burdensome sleep disorder, has been associated with cardiovascular disease (CVD), hypertension, diabetes, and related disorders. However, the relationship of RLS to history of pregnancy-induced hypertension (PIH), a predictor of subsequent CVD, diabetes, and associated conditions, remains little explored. In this study, we investigated the relationship of RLS to history of PIH in a sample of primary care patients.

METHODS

Participants were women aged ≥40 years drawn from an anonymous survey study of West Virginia primary care patients. Data collected included detailed information on demographics, lifestyle factors, sleep patterns, and reproductive/medical history; the survey also included an RLS diagnostic questionnaire. Women who were pregnant or unsure about their pregnancy status were excluded from the analyses.

RESULTS

Of the 498 participants in the final analytic sample, 24.5% met diagnostic criteria for RLS (17.9% with symptoms ≥once/week, 11.9% with symptoms ≥3 times/week); 73 (16.5% of parous women) reported a history of PIH, defined as physician-diagnosed preeclampsia or gestational hypertension. After adjustment for demographics, lifestyle characteristics, obesity, reproductive history, health conditions, and other factors, those reporting a history of PIH were approximately twice as likely to meet criteria for RLS (odds ratio [OR] = 1.9; 95% confidence interval [CI] = 1.1, 3.6). These associations increased in magnitude with increasing symptom frequency (adjusted OR for RLS with symptoms ≥3 times/week = 3.8; CI 1.9, 7.6; p for trend = 0.003).

CONCLUSIONS

History of PIH was strongly and positively related to current RLS in this study of primary care patients; these findings further support a possible role for metabolic dysregulation in RLS etiology.

The Humanistic and Economic Burden of Restless Legs Syndrome

Objectives

To evaluate the humanistic and economic burden of a restless legs syndrome (RLS) diagnosis with regard to health-related quality of life, work productivity loss, healthcare resource use, and direct and indirect costs.

Study Design

Self-reported data came from the 2012 National Health and Wellness Survey (NHWS), a large, annual, nationally representative cross-sectional general health survey of US adults.

Methods

RLS patients (n = 2,392) were matched on demographic and health characteristics to Non-RLS respondents via propensity score matching differences between groups were tested with Bivariate and multivariable analyses.

Results

RLS patients had significantly lower health-related quality of life scores: Mental Component Summary (44.60 vs. 48.92, p<.001), Physical Component Summary (40.57 vs. 46.78, p<.001), Health Utilities (.63 vs. .71, p<.001) and higher levels of work productivity loss in the past seven days including absenteeism (8.1% vs. 9.3%, p<.001), presenteeism (26.5% vs. 15.8%, p<.001), and overall productivity loss (30.1% vs. 18.1%, p<.001) as well as general activity impairment (46.1% vs. 29.7%, p<.001). RLS patients had significantly higher healthcare resource use in the past 6 months than non-RLS patients: healthcare provider visits (7.46 vs. 4.42%, p<.001), ER visits (0.45 vs. 0.24, p<.001), and hospitalizations (0.24 vs. 0.15, p<.001). RLS patients also had higher estimated direct and indirect costs than non-RLS patients. Finally, it was found that across outcomes increasing severity is associated with increased economic and humanistic burden for RLS patients.

Conclusions

RLS patients suffer a greater humanistic and economic burden than those without RLS. Moreover as severity increases so does the burden of RLS.

The Association of Restless Legs Syndrome to History of Gestational Diabetes in an Appalachian Primary Care Population

OBJECTIVES

Restless legs syndrome (RLS) is a burdensome sensorimotor disorder that has been linked to diabetes and obesity. However, the relationship of RLS to gestational diabetes mellitus (GDM), a common pregnancy complication strongly associated with obesity and a harbinger of diabetes, remains unknown. In this study, we examined the association of RLS to history of GDM in a sample of older female primary care patients.

METHODS

Participants were community-dwelling women aged ≥ 40 years drawn from an anonymous survey study of West Virginia adult primary care patients. Data gathered included detailed information on demographics, lifestyle factors, reproductive history, sleep patterns, and medical history; the survey also included an RLS diagnostic questionnaire. Women who were pregnant or had missing data on key variables were excluded from the analyses.

RESULTS

Of the 498 participants included in the final analytic sample, 24.5% met diagnostic criteria for RLS (17.9% with symptoms at least once/week). After adjustment for demographics, lifestyle characteristics, body mass index, diabetes and other comorbid conditions, parity, and other factors, those reporting history of GDM were almost three times as likely to meet criteria for RLS (odds ratio [OR] = 2.7, 95% confidence interval [CI] = 1.3, 5.3). This association increased in magnitude with increasing symptom frequency (adjusted OR for RLS symptoms ≥ 3×/week = 4.8, CI 2.1, 11.2, p for trend = 0.004).

CONCLUSIONS

History of GDM was strongly and positively related to RLS in this study of older female primary care patients, offering further support for a possible role of metabolic dysregulation in RLS development.

Restless legs syndrome in Egyptian medical students using a validated Arabic version of the Restless Legs Syndrome Rating Scale

OBJECTIVE

Restless legs syndrome (RLS) is a common movement disorder that has a variable prevalence and impact reported from different countries and specific populations. The current study validated an Arabic version of the International Restless Legs Syndrome Study Group (IRLSSG) rating scale (IRLS) and investigated the prevalence and impact of RLS in medical students at Ain Shams University in Cairo.

METHODS

Translation of IRLS was done according to standard recognized guidelines provided by the publisher. A total of 389 medical students (217 female and 172 male) participated in the study and answered four questions to detect RLS as proposed by the IRLSSG. Subjects who answered positively the first three questions were recruited for face-to-face interview to exclude RLS mimics and to answer the IRLS.

RESULTS

A total of 46 subjects (11.8%; 27 female and 19 male) met the four criteria for RLS. Of these, 39 subjects (10%) had idiopathic RLS. Five subjects (1.3%) and two subjects (0.5%) reported association with history of anemia and diabetes mellitus respectively. Their mean total IRLS score was 16.33 ± 5.3, with moderate severity (11.62 ± 3.9) and low impact (3.1 ± 1.8). The prevalence of individuals who had two or more episodes of RLS of at least moderate severity per week was 5.9%.

CONCLUSION

In this specific population of Egyptian medical students, a within-average prevalence of RLS was found with low impact on quality of life similar to worldwide reported populations. RLS sufferers were of high prevalence among this cohort. The Arabic version of IRLS is reliable and valid for further research in Arabic countries.

Racial differences in the prevalence of restless legs syndrome in a primary care setting

STUDY OBJECTIVE

To assess the prevalence of restless legs syndrome (RLS) in a primary care clinic and in African American (AA) and non-African American (NAA) racial groups.

METHODS

We examined the prevalence of RLS using 1-on-1 interviews in general medicine clinics. Subjects were interviewed using John Hopkins Telephone Diagnostic Interview. All interviews were conducted by trained physicians.

RESULTS

A total of 190 patients were interviewed: 103 AA (58.3% were female) and 87 NAA (59.8% were female). The overall prevalence of definite RLS was 22.6%. The average age was 53 years (standard deviation, 15) in AA and 50 years (standard deviation, 13) in NAA. Among AA, the diagnosis of RLS was definite in 11.65%, probable in 3.88%, negative in 83.5%, and unknown in 0.97%. Among NAA, patients were either identified as definite RLS (35.63%) or not RLS (64.37%); no patients were diagnosed as probable RLS or unknown. Logistic regression analysis was done to determine whether age, race, and sex were statistically significant predictors of an RLS diagnosis. When accounting for the other variables, the association between NAA and RLS prevalence was statistically significant (P = 0.002).

CONCLUSION

Restless legs syndrome is common among primary care clinic patients. Its prevalence in the NAA population is approximately 3 times higher than in the AA group. We found the association between NAA race and RLS prevalence to be statistically significant. Larger studies are needed to further examine the relation between race and RLS prevalence.