Individuals with Restless Legs Syndrome Tend to have Severe Depressive Symptoms: Findings from a Community-Based Cohort Study

Assessment of Sleep Disturbances on Mental Health in Patients with Restless Legs Syndrome

Background and Objective

In our study, we aimed to evaluate the sleep disturbances of patients diagnosed with restless legs syndrome (RLS) regarding their mental health according to the severity of the disease.

Materials and Methods

The study included 166 patients diagnosed with RLS and 161 healthy controls in the same age interval as patients. Sleep disturbances of patients were defined with the "personal information form" (PIF) prepared by the researchers, while the mental health status of patients was defined with the "Brief Symptom Inventory" (BSI).

Results

All RLS patients had an increase in BSI subscale points, with a positive correlation to disease severity, and subscale points were significantly higher than the control group (p < 0.05). Those with the "frequent waking" problem had higher BSI subscale points compared to those without the problem (p<0.01 or 0.001). Those with "waking with respiratory distress," "daytime sleepiness," "very early waking," and "sleep disorder" problems had statistically significantly high BSI subscale points for all subscales, apart from hostility, compared to those without these problems (p<0.01 or 0.001).

Conclusion

It is considered that assessment of sleep disturbances causing disrupted quality of life and mood disorders is beneficial for the treatment of patients with RLS. Our study data appears to be related to the result that sleep disturbances and mental health disruptions might be associated with the disease severity among RLS patients.

Depressive Symptoms and Suicidal Thoughts in Restless Legs Syndrome

BACKGROUND

Whether depression and suicide thoughts relate to restless legs syndrome (RLS) or comorbidities associated with RLS remain unclear.

OBJECTIVES

To determine frequency of depressive symptoms and suicidal thoughts in patients with RLS and their change after RLS treatment, associated clinical and polysomnographic factors, and current major depressive episode (MDE) frequency and suicide risk in RLS.

METHODS

Overall, 549 untreated patients with RLS and 549 age-, sex-, and education level-matched controls completed a standardized evaluation, including the Beck Depression Inventory-II that has one item on suicide thoughts. Patients underwent a polysomnographic recording and completed the Urgency, Premeditation, Perseverance, Sensation Seeking Impulsive Behavior scale. In a subgroup of 153 patients, current MDE and suicide risk were assessed with the face-to-face Mini-International Neuropsychiatric Interview (MINI). A subgroup of 152 patients were evaluated in untreated and treated conditions.

RESULTS

The frequency of depressive symptoms (32.5%) and suicidal thoughts (28%) was 10-fold and 3-fold higher, respectively, in patients with RLS than controls. Current MDE (10.5%) and suicidal risk (19.9%) (MINI) were also high. Moderate-to-severe depressive symptoms were associated with young age, female sex, insomnia symptoms, and urgency dimension. The suicide risk was associated with depression, impulsiveness, and RLS severity. RLS treatment improved depressive symptoms but not suicidal thoughts.

CONCLUSION

The rate of depressive symptoms, depression, and suicidal thoughts/risk was higher in patients with RLS, with key associations with insomnia symptoms, urgency dimension, and RLS severity. These results emphasize the importance of detecting these symptoms in current practice and of evaluating their change after treatment, especially in young women, to improve RLS management. © 2022 International Parkinson and Movement Disorder Society.

Association Between CLOCK Gene Variants and Restless Legs Syndrome in Koreans

OBJECTIVE

Previous studies have suggested various causes of restless legs syndrome (RLS), including iron and dopamine concentrations in the brain. Genetic influences have also been reported in many studies. There is also a possibility that circadian clock genes may be involved because symptoms of RLS worsen at night. We investigated whether CLOCK and NPAS2 gene polymorphisms were associated with RLS.

METHODS

A total of 227 patients with RLS and 229 non-RLS matched controls were assessed according to the International Restless Legs Syndrome Study Group diagnostic criteria. Genotyping was performed using reverse transcription polymerase chain reaction and high-resolution melting curve analyses.

RESULTS

Although the genotype distributions of the CLOCK variants (rs1801260 and rs2412646) were not significantly different between patients with RLS and non-RLS controls, the allele frequencies of CLOCK rs1801260 showed marginally significant differences between the two groups (X2 =2.98, p=0.085). Furthermore, there was a significant difference in the distribution of CLOCK haplotypes (rs1801260-rs2412646) between patients with RLS and non-RLS controls (p=0.013). The distributions of allelic, genotypic, and haplotypic variants of NPAS2 (rs2305160 and rs6725296) were not significantly different between the two groups.

CONCLUSION

Our results suggest that CLOCK variants may be associated with decreased susceptibility to RLS.

Leg Movements during Sleep in Children Treated with Serotonergic Antidepressants

STUDY OBJECTIVES

To evaluate leg movements during sleep (LMS) in children taking serotonergic antidepressants, compared to those of children with restless legs syndrome (RLS) and controls, and to assess the time structure of intermovement intervals (IMI).

METHODS

Twenty-three children (12 girls, mean age 14.1 years) on antidepressants and with a total LMS index ≥15/hour, 21 drug-naïve RLS children (11 girls, mean age 13.6 years) also with total LMS index ≥15/hour, and 35 control children (17 girls, mean age 14.3 years) were recruited. LMS were scored and a series of parameters was calculated, along with the analysis of their time structure.

RESULTS

Children taking antidepressants showed higher total and periodic LMS (PLMS) indexes than both controls and RLS children, as well as higher short-interval and isolated LMS indexes than controls. LMS periodicity was highest in children on antidepressants. In children taking antidepressants, a well-defined PLMS IMI peak corresponding to ~10-60 s, with a maximum at ~20 s was present, which was much less evident in RLS patients and absent in controls. A progressive decrease of PLMS during the night and more frequent arousals were found in children on antidepressants and with RLS.

CONCLUSIONS

Children taking serotonergic antidepressants show higher periodicity LMS than children with RLS or controls and have a higher number of PLMS through the night. Antidepressant-associated PLMS in children seem to have features similar to PLMS of adults with RLS. Whether this is a marker of an increased risk to develop RLS later in life needs to be determined.

The Long-Term Psychiatric and Cardiovascular Morbidity and Mortality of Restless Legs Syndrome and Periodic Limb Movements of Sleep

Restless legs syndrome (RLS) is a sensory-motor neurological disorder that is associated with high levels of distress and sleep disturbance. Cross-sectional and longitudinal evidence suggests that individuals suffering from RLS may be at an increased risk of certain psychiatric illnesses and cardiovascular diseases. There also is evidence for increased mortality rates in RLS patients, although contrasting results do exist. Periodic limb movements of sleep (PLMS), repetitive leg movement observed in most RLS patients, and sleep disturbance may mediate the relationship between RLS and long-term morbidity. This article summarizes the literature investigating the potential consequences of both RLS and PLMS.

Risk factors for sleep disorders in patients undergoing peritoneal dialysis

Sleep disorders in patients with end-stage renal disease are common but have rarely been reported in previous studies. Therefore, we examined the prevalence of sleep disorders and the risk factors for declining sleep quality in patients undergoing peritoneal dialysis (PD). A multicenter prospective cohort study was conducted at five PD centers across different provinces in China. A total of 449 patients who underwent PD between March to November 2013 were enrolled. Demographic data, laboratory indicators, presence of depression, and sleep assessment data were collected. Sleep questionnaires reflecting five categories of sleep disorders, namely, insomnia, restless legs syndrome, excessive daytime sleepiness, possible narcolepsy, and sleepwalking and nightmares, were administered at baseline and at 24 months postoperatively. Sleep disorders were diagnosed when a patient had at least one sleep problem. At baseline, 335 (74.6%) patients had at least one type of sleep disorder. Depression, diabetes mellitus (DM), and male were found to be associated with the presence of a sleep disorder. At follow-up, the prevalence of insomnia, restless legs syndrome, and excessive daytime sleepiness had significantly increased in 285 patients. Furthermore, cardiovascular disease (CVD) was found to be associated with the presence of sleep disorders in patients with one or more disorders at baseline, whereas a low serum albumin level was found to be associated with sleep disorders in patients without any sleep disorders at baseline. The prevalence of sleep disorders was relatively high among PD patients at baseline and increased afterthe2-year follow-up. Depression, DM, and male were associated with all sleep disorders at baseline. CVD was associated with the presence of a sleep disorder at baseline and worse sleep quality at the 2-year follow-up; whereas a low serum albumin level was associated with the risk of acquiring a sleep disorder at the 2-year follow-up among patients with normal sleep status at baseline.

Restless Legs Syndrome During Pregnancy and 12 Weeks Postpartum and its Links to Cardiovascular Diseases, Stressful Life Events, and Psychiatric History

Restless legs syndrome (RLS) is highly prevalent among pregnant women. In the present study, a neurological-obstetrical sample of 561 postpartum women was retrospectively screened for RLS symptoms during pregnancy and in the first 12 weeks postpartum. The first screening took place within 1 to 6 days of delivery (T0) and the second 12 weeks after childbirth (T1). The pregnancy-related RLS prevalence rate was found to be 21% (n = 119), with the women suffering from RLS being more often affected by psychiatric history and having been more exposed to stressful life events. They were also found to have experienced baby blues more frequently shortly after childbirth. However, RLS in pregnancy did not appear to have any effect on the development of postpartum depression. Additionally, a positive trend was observed toward an association between pregnancy-related RLS and gestational diabetes and hypertension. Of the 119 women, 23 (19.3%) remained affected by RLS 12 weeks postpartum. Body mass index (BMI), weight gain, parity, childbearing history, or chronic stress exposure in pregnancy as measured by hair cortisol were not found to be linked to RLS. In summary, a comprehensive understanding of the interaction of clinical, environmental, and anamnestic factors can help shed valuable light on this pregnancy-related condition.

Association between leg motor restlessness and depression among Chinese males living at high-altitude: the mediating role of insomnia

OBJECTIVE

Previous research has documented an association between insomnia and depression among patients with restless legs syndrome (RLS)/Willis-Ekbom disease. Given that leg motor restlessness (LMR) is closely related to RLS, the purpose of this study was to investigate the prevalence of insomnia and depression among individuals with LMR. In addition, we examined the associations among LMR, insomnia, and depression in a sample of young Chinese men living in high-altitude areas.

METHODS

Chinese military personnel working on the Qinghai Tibet Plateau (Lhasa, an altitude of 3600 m) were recruited in 2019 to complete a series of questionnaires. Participants having the urge to move their legs but not meeting the diagnostic criteria for RLS were classified as having LMR. Hierarchical linear regressions and mediational analyses using the SPSS PROCESS macro in SPSS were conducted to examine the associations among LMR, insomnia, and depression.

RESULTS

Of 196 participants, 36 (18%) had LMR. Only 1 participant was diagnosed with RLS. The proportions of participants suffering from insomnia who had LMR and did not have LMR were 44% and 22%, respectively. For depression, the proportions were 47% and 28%, respectively. Results of the hierarchical linear regressions showed that both LMR and depression were associated with increased insomnia symptoms. In addition, results from the mediational analyses indicated that the indirect effect of LMR on depression was significant and accounted for 52% of the total effect.

CONCLUSIONS

Participants with LMR had a higher prevalence of insomnia and depression compared with those without LMR. In addition, LMR was correlated with depression, and insomnia played a significant role in this co-occurrence.

The influence of restless legs symptoms on musculoskeletal pain in depression

Background and aims Restless legs syndrome is a sensorimotor disorder associated with mental health conditions notably depression. Restless legs symptoms and depression are commonly associated with pain. The study investigated the influence of restless legs symptoms on musculoskeletal pain in patients with depression or with increased depressive symptoms. Methods A cross-sectional study of primary care patients in the Central Finland Hospital District. The prevalence of restless legs symptoms was studied in patients with depressive symptoms (n = 695) and controls without a psychiatric diagnosis (n = 410) by using a structured questionnaire. The depressive symptoms were evaluated with the Beck Depression Inventory and the psychiatric diagnosis was confirmed by means of a diagnostic interview (MINI). The prevalence and intensity of musculoskeletal pain was captured with form-based questions. A single-question screen for restless legs symptoms was applied. Results There was a significant difference in the prevalence of continuous widespread musculoskeletal pain between the three study groups: the controls 4.6% (95% CI: 2.8-7.1), the patients with symptoms of depression without a diagnosis 16.0% (11.7-21.1), and the patients with diagnosed depression 22.1% (18.3-23.3) (p = 0.006 after being adjusted for age, sex, smoking, use of alcohol, education years, body mass index, use of antidepressants, and physical activity, after multiple corrections, all groups were significantly different from each other). Compared with those not having restless legs symptoms, subjects with restless legs symptoms had more often continuous widespread musculoskeletal pain in the control subjects (p = 0.001; 2.3% vs. 10.5%) and in the patients with depressive symptoms without a depression diagnosis (p = 0.024; 9.1 vs. 18.7%) but not in those with diagnosed depression (p = 0.98; 19.5 vs. 19.4%). The restless legs symptoms were associated with the intensity of pain in all groups (p < 0.001). Conclusions Restless legs symptoms were related to continuous widespread musculoskeletal pain in subjects without depressive symptoms and in patients with depressive symptoms without a depression diagnosis. Pain intensity was higher in the subjects with restless legs symptoms regardless of depressive symtoms or depression. Implications Clinical management of pain in patients with restless legs symptoms should include an increased focus on the prevention and treatment of either conditions.

Assessment of serum uric acid levels in patients with restless legs syndrome

In our study, the aim was to collect data in relation to our hypothesis that oxidative stress is effective in the etiopathogenesis of restless legs syndrome (RLS) by assessing the serum uric acid levels, an important biomarker of oxidative stress, among RLS patients. The study included a total of 281 patients with restless legs syndrome diagnosis according to the "2012 Revised International Restless Legs Syndrome Study Group Diagnostic Criteria". Disease severity was assessed according to the "International Restless Legs Syndrome Study Group Severity Scale". The control group comprised 237 healthy individuals with the same age and gender features as the control group. The result showed no statistically significant difference in the mean age and gender between RLS and control group (p = 0.923; p = 0.433). The hemoglobin, ferritin, and uric acid levels of patients with RLS were found to be low (p < 0.001). Total iron-binding capacity level was higher in patients (p < 0.01; p < 0.05). In RLS patients, the serum uric acid level was not affected by disease severity (p > 0.05). Variables affecting uric acid level in RLS patients were determined to be age, disease duration, and hemoglobin level. The hypothesis that uric acid level, accepted as a biomarker of oxidative stress, is important in the pathogenesis of restless legs syndrome is supported by our study.

Association of Restless Legs Syndrome With Risk of Suicide and Self-harm

IMPORTANCE

Restless legs syndrome (RLS) is a common neurologic disorder that has been previously found to be associated with higher odds of suicidal ideation. In the context of the increasing suicide rate in the United States, the evidence regarding the association between RLS and the risk of suicide and self-harm is limited.

OBJECTIVE

To investigate the association between RLS and risk of suicide and self-harm.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study was performed using Truven Health MarketScan national claims data from 2006 to 2014; the baseline data were from 2006 to 2008, and the follow-up data covered 6 years (January 1, 2009, to December 31, 2014). Included were 24 179 nonpregnant participants with RLS and 145 194 age- and sex-matched participants without RLS at baseline (2006-2008), who were free of suicide, self-harm, cardiovascular disease, or cancer at study baseline. Data analysis was performed from February 1, 2018, to January 1, 2019.

EXPOSURE

Diagnosis of RLS, as identified by the International Classification of Diseases, Ninth Revision code.

MAIN OUTCOMES AND MEASURES

Incident suicide and self-harm event, identified by the International Classification of Diseases, Ninth Revision diagnosis code.

RESULTS

Among 169 373 participants in the current analysis, the mean (SD) age was 49.4 (9.1) years; 53 426 (31.5%) participants were men. During a mean (SD) follow-up duration of 5.2 (2.2) years, 119 incident suicide and self-harm cases were identified. Individuals with RLS had a higher risk of suicide or self-harm compared with those without RLS (adjusted hazard ratio, 2.66; 95% CI, 1.70-4.15), after adjusting for lifestyle factors (eg, alcohol and obesity), presence of chronic diseases (eg, depression, insomnia, diabetes, chronic kidney disease, peripheral neuropathy, iron-deficiency anemia, and Parkinson disease), and use of medications. Excluding those with depression, insomnia, obstructive sleep apnea, and other common chronic conditions, the significant association between RLS and suicide or self-harm persisted (adjusted hazard ratio, 4.14; 95% CI, 2.17-7.92).

CONCLUSIONS AND RELEVANCE

Restless legs syndrome was associated with a high risk of suicide and self-harm, and the risk was independent of most identified diseases and conditions.

Serum C-reactive protein/albumin ratio and restless legs syndrome

OBJECTIVES

Our study aimed to assess the variation in serum C-reactive protein/albumin ratio (CAR), a biomarker of peripheral inflammation and oxidative stress, in patients with restless legs syndrome (RLS).

METHODS

The study included a total of 380 individuals including 197 with RLS diagnosis. RLS diagnosis was determined according to the "International Restless Legs Syndrome Study Group" questionnaire. Disease severity was assessed according to the "International Restless Legs Syndrome Study Group Severity Scale''.

RESULTS

The mean age of patients with restless legs syndrome was 52.5 ± 12.7 years, while the mean age in the control group was 50.8 ± 11.2, with no statistically significant difference found (p = 0.156). The hemoglobin, iron and ferritin levels in the patient group were lower than in the control group (p < 0.001; p < 0.01; p < 0.001), with total iron binding capacity levels higher than the control group (p < 0.001). The mean ferritin in the RLS group (49.8 ± 51.2) was lower than the control group (76.9 ± 44.7). In patients, the c-reactive protein, albumin and c-reactive protein/albumin ratio were found to be 0.21 ± 0.18, 4.43 ± 0.31 and 0.07 ± 0.05, respectively. When compared with the control group, the patient group had high c-reactive protein (CRP), CAR and low albumin levels (p < 0.001). Among patients with "very severe" disease severity, ferritin levels were found to be lower than those with "moderate" disease severity. Additionally, patients with "very severe" disease had albumin levels which were significantly low compared to those with "mild" disease severity (p < 0.05).

CONCLUSION

Our study supports the hypothesis that serum albumin level, ferritin, CRP, and CAR may be associated with restless legs syndrome.

Depression is differently associated with sleep measurement in obstructive sleep apnea, restless leg syndrome and periodic limb movement disorder

Depression causes sleep disturbance and is associated with various sleep-related disorders. However, how depression affects the symptomatic presentation of different sleep-related disorders is unclear. In this study, we investigated the sleep parameters of different sleep-related disorders between depressive and non-depressive patients. A total of 785 patients underwent polysomnography in a mental hospital from Jan 2012 to Jun 2013. We first analyzed variables between the depressive and non-depressive groups. The patients were then divided into four groups: obstructive sleep apnea (OSA, n = 339), restless leg syndrome (RLS, n = 51), periodic limb movement disorder (PLMD, n = 58) and comorbid group (OSA and RLS, n = 46). We next compared sleep measures between the depressive and non-depressive subjects within each groups. The patients with OSA and depression were significantly associated with a higher periodic limb movement index. Significantly more patients with RLS patients and depression had initial insomnia complaints. However, significantly more patients with PLMD and depression middle insomnia. Compared with non-depressive population, depressive patients had higher comorbidity with RLS and PLMD. Depression may have different association with the sleep parameters in different sleep-related disorders. Further investigations are needed to investigate how these findings may affect patients' awareness and clinicians' diagnosis and management of sleep-related disorders.

Comorbidities, treatment, and pathophysiology in restless legs syndrome

Restless legs syndrome, also known as Willis-Ekbom disease, is a common neurological condition whose manifestation is affected by complex environmental and genetic interactions. Restless legs syndrome can occur on its own, mostly at a young age, or with comorbidities such as cardiovascular disease, diabetes, and arterial hypertension, making it a difficult condition to properly diagnose. However, the concept of restless legs syndrome as being two entities, primary or secondary to another condition, has been challenged with genetic data providing further insight into the pathophysiology of the condition. Although dopaminergic treatment was formerly the first-line therapy, prolonged use can result in a serious worsening of symptoms known as augmentation. Clinical studies on pregabalin, gabapentin enacarbil, oxycodone-naloxone, and iron preparations have provided new treatment options, but most patients still report inadequate long-term management of symptoms. Studies of the hypoxic pathway activation and iron deficiency have provided valuable information about the pathophysiology of restless legs syndrome that should now be translated into new, more effective treatments for restless legs syndrome.

Investigation of alexithymia and levels of anxiety and depression among patients with restless legs syndrome

PURPOSE

The purpose of this study was to examine alexithymia among restless legs syndrome (RLS) patients, compare with healthy controls, and argue the clinical inferences of this relationship. We searched for anxiety and depression and their clinical outcomes among patients and searched whether the results are similar to previous studies.

PATIENTS AND METHODS

Eighty-seven RLS patients and 88 age, gender, and educationally matched healthy controls were assessed in Bezmialem Foundation University Hospital. RLS patients and healthy controls were assessed with the Sociodemographic Data Form constructed for the present study, 20-item Toronto Alexithymia Scale (TAS-20), Beck Depression Inventory (BDI), and Beck Anxiety Scale (BAS). The patient group was also assessed with the International Restless Legs Syndrome Study Group (IRLSSG) RLS Severity Scale.

RESULTS

RLS patients were found to have greater TAS-20, BDI, and BAS scores compared with the control group (P < 0.05). RLS severity score was positively correlated with the scores of anxiety and depression scales. However, no significant relationship was found between scores of IRLSSG RLS scale and TAS-20 total and subscale scores.

CONCLUSION

RLS patients were found to be more alexithymic than healthy controls, whereas no significant relationship was found between RLS severity and levels of alexithymia. Still, alexithymia might be a predictor for early diagnosis and may be considered in the treatment and follow-up of RLS. RLS patients have higher depression and anxiety scores than healthy individuals. Thus, depression and anxiety should be taken into consideration throughout the RLS treatment.