Restless Legs Syndrome: Associated Risk Factors in Hemodialysis Patients

Association between Chronic kidney disease and restless leg syndrome (RLS): a systematic review and meta-analysis

Restless leg syndrome (RLS) is characterized by unpleasant nocturnal sensations in the lower limbs, and it has emerged as the fourth leading cause of insomnia and is often an underdiagnosed medical condition among sleep disorders. The symptoms of RLS are more common in chronic kidney disease patients than in the general population. Therefore, we performed the first meta-analysis to estimate the risk of RLS among chronic kidney disease patients. We conducted a comprehensive search in Embase, Ovid-MEDLINE, PubMed, Scopus, Web of Science, and CINAHL databases. Data were analyzed with the random-effects model using Comprehensive Meta-Analysis (CMA) software to find the odds ratio (OR). The heterogeneity was checked with the I2 test and Cochran's Q-statistic, and we performed the moderator analysis to find potential sources of heterogeneity. The study quality was assessed using the Newcastle-Ottawa Scale. Of 1175 studies, we found nine studies, with a total of 18,983 participants. The pooled OR of RLS among chronic kidney disease was 5.64 (95%CI 2.70-11.78). Regarding moderator analysis results, it was observed that higher body mass index and abnormal laboratory results would increase the risk of RLS; however, the statistical test was not significant in the current study. The findings reveal a substantial sixfold increase in the likelihood of RLS when compared to the general population. Therefore, health professionals should encourage patients to adhere to the treatment and practice a healthy lifestyle to manage their condition and reduce the risk of RLS. Moreover, future research can develop an intervention to reduce RLS symptoms.

Supplementary Information

The online version contains supplementary material available at 10.1007/s41105-024-00513-4.

Prevalence of restless legs syndrome in maintenance hemodialysis patients: A systematic review and meta-analysis

BACKGROUND

Restless legs syndrome is associated with quality of life and risk of death in maintenance hemodialysis patients. Although relevant meta-analyses have been conducted, epidemiological studies of restless legs syndrome have increased in recent years.

OBJECTIVE

Our aim was to systematically assess the prevalence of restless legs syndrome in maintenance hemodialysis patients and to evaluate the effect of different geographic regions, genders, study designs, and years of publication on the prevalence of restless legs syndrome.

METHODS

PubMed, Web of Science, EMBASE, The Cochrane Library, China Knowledge Resource Integrated Database, Wanfang Database, Weipu, and Chinese Biomedical Database were searched before March 16, 2023 for the published literature. Two investigators independently performed literature screening, data extraction for eligible studies, and risk of bias assessment. A random-effects model using the stata 15.0 software was used to assess the pooled prevalence of restless legs syndrome.

RESULTS

Fifty-seven articles were included in this meta-analysis, and the pooled prevalence of restless legs syndrome in 12,573 maintenance hemodialysis patients was 24.0 % (95 % CI: 21.0%-26.0 %). Maintenance hemodialysis patients from the Americas region and females had severe symptoms of restless legs syndrome, and the prevalence of restless legs syndrome increased from year to year. The prevalence of restless legs syndrome was higher in maintenance hemodialysis patients in cross-sectional studies and cohort studies compared to case-control studies.

CONCLUSIONS

Maintenance hemodialysis patients have a significantly higher prevalence of restless legs syndrome. These findings may provide some reference value for hospital nursing staff to focus on the management and treatment of restless legs syndrome in maintenance hemodialysis patients.

Association between thyroid function and disease severity in restless legs syndrome

Background

Restless Legs Syndrome (RLS) is a common neurological disorder. Growing evidence shows that dopaminergic dysfunction and iron deficiency are associated with the pathogenesis of RLS. Additionally, the dopaminergic system is linked with the hypothalamic-pituitary-thyroid (HPT) axis. Thus, the current study aimed to compare thyroid function between RLS patients and healthy subjects and investigate the associations with clinical characteristics of RLS.

Methods

Serum levels of thyroid hormones were investigated in 102 first-episode drug-naïve RLS patients and 80 matched healthy controls (HCs). Baseline data and clinical characteristics were performed by professional personnel. In addition, multivariate regression was used to analyze the relationship between thyroid function and RLS.

Results

Compared with control group, RLS patients had significantly higher serum thyroid-stimulating hormone (TSH) levels (p < 0.001), and higher prevalence of subclinical hypothyroidism [Odds ratio (OR) 8.00; 95% confidence interval (CI) = 3.50–18.30; p < 0.001]. The Subclinical hypothyroidism rate (47.1 vs. 10%, p < 0.001) in RLS patients was higher than the HCs group. Regression analysis revealed that serum TSH (OR = 1.77; 95% CI = 1.41–2.23; p < 0.001) was independently associated with RLS. There was a statistically significant positive correlation between TSH and the Pittsburgh sleep quality index (PSQI) scores (r = 0.728, p < 0.001), and the International Restless Legs Scales (IRLS) points (r = 0.627, p < 0.001). Spearman correlation analysis showed that FT₃ was positive correlated with HAMA₁₄ score (r = 0.239, p = 0.015). In addition, compared with the good-sleeper group, poor-sleeper patients had significantly higher serum TSH levels (p < 0.001).

Conclusion

Serum levels of TSH and the prevalence of subclinical hypothyroidism were higher in RLS patients, indicating the imbalance between thyroid hormones (TH) and the dopaminergic system may contribute to the development of primary RLS. Additionally, the TH axis may influence the quality of sleep in RLS patients.

El efecto de la relajación muscular progresiva en la reducción del síndrome de las piernas inquietas entre los pacientes sometidos a hemodiálisis en una unidad periférica en Indonesia

Introducción: La relajación muscular se considera una terapia alternativa para el síndrome de las piernas inquietas (SPI). Objetivo: Determinar el efecto de la relajación muscular progresiva (RMP) sobre el síndrome de piernasinquietas en pacientes sometidos a hemodiálisis. Metodología: Se llevó a cabo un estudio con diseño cuasi-experimental en la unidad de hemodiálisis. Lamuestra reclutada fue de 12 encuestados tanto en el grupo de intervención como en el de control, siendo elmuestreo de conveniencia. El instrumento de investigación utilizado fue la Escala Internacional del Grupo de Estudio del SPI. Resultados: En el grupo de intervención, las puntuaciones medias del SPI antes y después fueron de22,92 y 17,42, respectivamente. En el grupo de control, las puntuaciones medias del SPI antes y despuésde la intervención fueron de 24,33 y 23,50, respectivamente. La RPM fue eficaz para mejorar el SPI (p<0,005). Conclusión: La RMP podría ser una alternativa para reducir el SPI en pacientes sometidos a hemodiálisis. Se necesitan estudios futuros para aclarar los hallazgos utilizando métodos más robustos y un tamaño de muestra mayor.

Analysis of Serum Vitamin D Level and Related Factors in Patients With Restless Legs Syndrome

Objective: This study aimed to detect serum vitamin D (VitD) levels in patients with primary restless legs syndrome (RLS). The further objective was to analyze the relationship of VitD levels with the severity of RLS symptoms, sleep, anxiety, and depression.

Methods: The serum 25-hydroxyvitamin D [25(OH)D] levels of 57 patients with primary RLS and the healthy physical examinees in our hospital during the same period were detected. The International Restless Legs Syndrome Study Group (IRLSSG) rating scale for measuring RLS severity and Pittsburgh Sleep Quality Index (PSQI) Scale, 24-item Hamilton Depression Rating Scale (HAMD₂₄), and 14-item Hamilton Anxiety Scale (HAMA₁₄) were used to assess the severity of symptoms, sleep, and emotional state of patients with RLS. Based on VitD level and IRLSSG score, they were grouped for analysis.

Results: The serum 25(OH)D level was significantly lower in patients with RLS than in healthy controls, and the incidence of insufficient serum VitD levels was significantly higher in patients with RLS than in healthy people (both P < 0.05). The serum VitD level was significantly lower in (extremely) severe patients with RLS than in mild to moderate patients with RLS (P < 0.05). The IRLSSG scale score and HAMD₂₄ score were significantly higher in patients with RLS with insufficient serum VitD levels than those with normal serum VitD levels (both P < 0.05). Correlation analysis of IRLSSG scale score with serum VitD level and each scale score in patients with RLS showed that IRLSSG scale score was negatively correlated with VitD level, but positively correlated with PSQI, HAMA₁₄, and HAMD₂₄ scores. The results of correlation analysis between serum VitD levels and each scale score in patients with RLS indicated that serum VitD levels were negatively correlated with IRLSSG scale scores, PSQI scores, and HAMD₂₄ scores.

Conclusion: The serum VitD level is generally lower in patients with RLS than in healthy people, and lower serum VitD level is associated with more severe symptoms of RLS, worse quality of sleep, and worse depression.

Association of quality of life, anxiety, and depression with restless leg syndrome in the hemodialysis patients

OBJECTIVES

Restless Legs Syndrome (RLS) is commonly known to cause morbidity in patients on hemodialysis, making them prone to chronic mental health illnesses such as depression and anxiety, and also adversely impact quality of life. In this study, we examined the association of quality of life, anxiety, and depression with restless leg syndrome in the hemodialysis patients at Karachi Institute of Kidney Diseases.

RESULTS

About 26.7% of the participants reported RLS among the sample size Presence of RLS was not associated with quality of life, depression, and anxiety. However, p-values < 0.05 were significant for body-mass index (BMI), diabetes mellitus as a cause of end-stage renal disease, and serum albumin levels. Majority (82.5%) of the RLS-diagnosed patients had moderate to severe symptoms with 16 (40%) and 17 (42.5%) clients, respectively.

Are serum vitamin D, calcium and phosphorous associated with restless leg syndrome? A systematic review and meta-analysis

BACKGROUND

It is hypothesized that vitamin D deficiency, and calcium/phosphate imbalance could be involved in the pathophysiology of restless leg syndrome (RLS). This systematic review and meta-analysis of observational studies were carried out to reach a firm conclusion regarding the possible association between vitamin D, calcium and phosphorous levels with RLS in end-stage renal disease (ESRD) patients, other comorbidities and healthy population.

METHODS

PubMed, Scopus, ISI Web of Science, and Cochrane's library were systematically searched up to June 2020. Quality assessment of the included observational studies was performed using Newcastle-Ottawa Quality Assessment Scale. Statistical analyses were done using STATA 11.2. A P-value <0.05 were considered statistically significant.

RESULTS

A total of 36 studies involving 9590 participants were included in this systematic review and meta-analysis. We found that serum vitamin D level is significantly lower (WMD -3.39 ng/mL; 95% CI, -5.96 to -0.81; P = 0.010; I² = 86.2%) and phosphorous (SMD 0.19; 95% CI, 0.04-0.34; P = 0.011; I² = 83.6%) is significantly higher in RLS individuals compared to the non-RLS individuals. However, the mean difference of serum calcium was not significant in comparison between RLS and control groups (SMD -0.01; 95% CI, -0.19 to 0.18; P = 0.957; I² = 89.2%).

CONCLUSION

Results revealed a significant association between serum vitamin D and phosphorous with RLS. However, further prospective cohort studies and clinical trials are needed for better understanding of the relationship between these variables.

Restless legs syndrome in end stage renal disease patients undergoing hemodialysis

BACKGROUND

The prevalence of Restless legs syndrome (RLS) in End Stage Renal Disease (ESRD) patients is higher than that in the general population. However, the associations of RLS within the ESRD population are inconsistent and RLS is usually neglected in dialysis centers, although it impairs the life quality among ESRD patients. We aim to investigate the prevalence of RLS in patients with ESRD undergoing maintenance hemodialysis and evaluate the risk factors of developing RLS and the effect of RLS on quality of life among ESRD patients.

METHODS

ESRD patients undergoing maintenance hemodialysis in Shanghai General Hospital dialysis unit from July 2016 to October 2016 were enrolled in the study. RLS was diagnosed according to the criteria of the International Restless Legs Syndrome Study Group (IRLSSG). IRLSSG Severity Scale was used to evaluate the severity of RLS. Pittsburgh Sleep Quality Index (PSQI) was used to evaluate sleep quality, and Hospital Anxiety and Depression Scale (HADS) was used to estimate anxiety and depression. Serologic and historic variables were analyzed to determine predictors of RLS in the ESRD population.

RESULTS

A total of 137 ESRD patients were enrolled. The prevalence of RLS among the ESRD patients was 20.44%. The risk of RLS was increased significantly in females (OR = 2.729, p = 0.032) and daily alcohol drinkers (OR = 4.716, p = 0.022). RLS increased the risks of sleep disorders (25/28, 89.3% vs 73/109, 67.0%, p = 0.02) and sedative hypnotics intake (7/28, 25.0% vs 10/109, 9.2%, p = 0.047) and impaired the sleep quality (7/109 vs 11/28, p = 0.001) according to PSQI sum scores.

CONCLUSION

A high RLS prevalence among the ESRD patients undergoing hemodialysis was confirmed. ESRD patients who are women and drinking alcohol have a higher risk of RLS. The sleep quality was significantly impaired and sleeping medication use was more common among the ESRD patients with RLS.

Alteraciones del sueño más frecuentes en las personas en diálisis

Introducción: La persona con enfermedad renal crónica en terapia dialítica presenta alteraciones en diferentes dimensiones de su vida, entre ellos el sueño, considerado una de las necesidades biológicas más importantes del organismo. Objetivo: Conocer las principales alteraciones del sueño en pacientes con ERC en tratamiento dialítico, los factores que influyen en su aparición y cuidados de enfermería. Metodología: Revisión narrativa de la literatura. Los criterios de inclusión fueron estudios primarios y revisiones sistemáticas, tanto cualitativos como cuantitativos, sobre alteraciones del sueño en pacientes adultos con ERC en terapia dialítica. Se consultaron las bases de datos Medline, Scielo y Epistemonikos. Resultados: La prevalencia de trastornos del sueño es alta en personas con enfermedad renal crónica que se someten a diálisis, las principales son síndrome de piernas inquietas y síndrome de apnea obstructiva del sueño. En el primero, el principal factor causal es el déficit de hierro y disfunción de dopamina, mientras que en el segundo son la sobrecarga de volumen y estrechez de vías respiratorias. El manejo responde a medidas farmacológicas como administración de hierro, agentes dopaminérgicos y uso de CPAP, además de medidas no farmacológicas que son transversales a ambos, como higiene del sueño. Conclusión: Las alteraciones del sueño en los pacientes en diálisis claramente repercuten en su calidad de vida, por lo que es un aspecto en que los profesionales de salud debiesen adquirir conocimientos y otorgar cuidados de enfermería específicos para prevenir, atenuar síntomas y evitar complicaciones.

Association of Hemodialysis Inadequacy and Duration with Restless Legs Syndrome: A Cross-sectional Study

Restless legs syndrome (RLS) is a common neurological disorder in hemodialysis (HD) patients. It is associated with poor sleep and decreased quality of life. The precipitants for the disorder are still poorly understood. The condition has not been studied extensively in Pakistan, which has a vast majority of end-stage renal disease patients on maintenance HD. We aimed to determine the prevalence of this condition in patients attending HD units of the largest renal dialysis center in Northern Pakistan. We also strived to determine any associations with dialysis inadequacy and the total duration of HD. This was an observational study comprising 279 patients. RLS was diagnosed using the International Restless Leg Syndrome Study Group criteria. Dialysis adequacy was determined using the Urea Reduction Ratio and the Kt/V technique. The prevalence of RLS in this large HD population was 24%. Our results show that a longer duration and greater number of HD sessions were significantly associated with the development of RLS (p<0.05). Dialysis inadequacy was not associated with the development of the disorder. These results may indicate that the pro-inflammatory nature of hemodialysis may have a role in the pathophysiology of RLS in HD patients and prolonged exposure to it may make them more prone to developing the disorder.

Exploring sleep disorders in patients with chronic kidney disease

Kidney disorders have been associated with a variety of sleep-related disorders. Therefore, researchers are placing greater emphasis on finding the role of chronic kidney disease (CKD) in the development of obstructive sleep apnea and restless legs syndrome. Unfortunately, the presence of other sleep-related disorders with CKDs and non-CKDs has not been investigated with the same clinical rigor. Recent studies have revealed that myriad of sleep disorders are associated with CKDs. Furthermore, there are a few non-CKD-related disorders that are associated with sleep disorders. In this narrative review, we provide a balanced view of the spectrum of sleep disorders (as identified in International Classification of Sleep disorders-3) related to different types of renal disorders prominently including but not exclusively limited to CKD.

Restless legs syndrome in hemodialysis patients

Restless legs syndrome (RLS) is a neurological disorder characterized by uncomfortable sensation of paresthesia in legs that subsequently causes involuntary and continuous movement of the lower limbs, especially at rest. Its prevalence in hemodialysis is more than that in the general population. Different risk factors have been suggested for RLS. We studied the prevalence and risk factors of RLS in 137 hemodialysis patients followed up at our center. The patients completed at least three months on dialysis and fulfilled four criteria for the diagnosis of RLS. We compared the patients with and without RLS, and the odds ratios (ORs) were estimated by the logistic regression models. The prevalence of RLS was 36.5% in the study patients. Among the variables, diabetes was the only predicting factor for the development of RLS. The diabetic patients may be afflicted with RLS 2.25 times more than the non-diabetics. Women developed severe RLS 5.23 times more than men. Neurodegeneration, decrease in dopamine level, higher total oxidant status, and neuropathy in diabetic patients may explain the RLS symptoms.