Disrupted white matter integrity in primary insomnia and major depressive disorder: relationships to sleep quality and depression severity.

This study examined the integrity of white matter tracts in 25 participants with primary insomnia (PI), 50 participants with major depressive disorder (MDD), and 25 healthy controls. Seven white matter tracts, selected based on prior research, were quantified by fractional anisotropy (FA) as well as by related measures of diffusivity using diffusion tensor imaging (DTI) on a 3-T scanner. All 100 participants were free of significant medical, psychiatric (excluding the MDD group) and sleep disorders (excluding the PI group), were free of central nervous system medications, and completed an extensive clinical assessment. Subjective and objective sleep measures revealed significant sleep disruption in both the PI and MDD groups. Relative to the controls, both the PI and MDD groups demonstrated impaired integrity in three of the seven white matter tracts: the genu of the corpus callosum (GenuCC), the superior longitudinal fasciculus (SLF), and the inferior longitudinal fasciculus (ILF). We demonstrated reduced FA in the GenuCC, reduced FA and reduced axial diffusivity (AD) in the SLF, as well as reduced AD and radial diffusivity in the ILF. Finally, in an exploratory analysis of the combined cohorts, FA in the GenuCC and FA in the SLF were negatively correlated with depression severity and positively correlated with total sleep time. Abnormalities documented in the GenuCC, SLF and ILF, and present in both the PI and MDD groups may suggest some shared neurobiology.

Association Between Subjective-Objective Discrepancy of Sleeping Time and Health-Related Quality of Life: A Community-Based Polysomnographic Study.

OBJECTIVE: This study aimed to investigate the existence of a difference in quality of life (QOL) between individuals with and without significant subjective-objective discrepancy (SOD) in total sleep time (TST). METHODS: From the Sleep Heart Health Study 2, 2540 individuals who had completed polysomnography, a morning sleep survey, and the 36-item Short-Form Health Survey (SF-36) were included in the analyses. The participants were classified as normoestimators (estimation of TST <±60 minutes), underestimators (underestimation of TST ≥60 minutes), or overestimators (overestimation of TST ≥60 minutes). The standardized SF-36 QOL scores were compared among the three groups. An adjusted partial correlation analysis was conducted between SOD and QOL. RESULTS: Of the 2540 participants, 1617 (63.7%), 433 (17.0%), and 490 (19.3%) were assigned to the normoestimator, underestimator, and overestimator groups, respectively. The bodily pain and social functioning components of the SF-36 score were significantly lower in the underestimators than in the normoestimators, whereas the physical functioning component was significantly lower in the overestimators than in the normoestimators. The absolute value of SOD in the TST showed a significant negative correlation with the physical and mental components of the SF-36. CONCLUSIONS: QOL was significantly better in the normoestimator than in the other groups and linearly correlated with the absolute value of SOD. This study suggests that a high prevalence of positive and negative sleep misperception in a community population can be a potential factor associated with poor QOL and potential comorbidities.

Consensus Guidelines on Rodent Models of Restless Legs Syndrome.

Restless legs syndrome (RLS) is a chronic sensorimotor disorder diagnosed by clinical symptoms. It is challenging to translate the diagnostic self-reported features of RLS to animals. To help researchers design their experiments, a task force was convened to develop consensus guidelines for experimental readouts in RLS animal models. The RLS clinical diagnostic criteria were used as a starting point. After soliciting additional important clinical features of RLS, a consensus set of methods and outcome measures intent on capturing these features-in the absence of a face-to-face interview-was generated and subsequently prioritized by the task force. These were, in turn, translated into corresponding methods and outcome measures for research on laboratory rats and mice and used to generate the final recommendations. The task force recommended activity monitoring and polysomnography as principal tools in assessing RLS-like behavior in rodents. Data derived from these methods were determined to be the preferred surrogate measures for the urge to move, the principal defining feature of RLS. The same tools may be used to objectively demonstrate sleep-state features highly associated with RLS, such as sleep disturbance and number and periodicity of limb movements. Pharmacological challenges and dietary or other manipulations that affect iron availability are desirable to aggravate or improve RLS-like behavior and lend greater confidence that the animal model being proffered replicates key clinical features of RLS. These guidelines provide the first consensus experimental framework for researchers to use when developing new rodent models of RLS. © 2020 International Parkinson and Movement Disorder Society.

Restless legs syndrome and perceived olfactory and taste dysfunction: A community-based study.

BACKGROUND AND PURPOSE: Restless legs syndrome (RLS) has been suggested as a prodromal symptom of Parkinson disease (PD). Olfactory or taste dysfunction can also occur preceding PD diagnosis. However, whether RLS is associated with chemosensory dysfunction remains unknown. We thus aim to investigate the association between RLS and perceived olfactory and taste dysfunction. METHODS: We performed a cross-sectional analysis including 90,337 Chinese adults free of neurodegenerative diseases in the Kailuan study in 2016. Presence of RLS was defined using revised RLS diagnostic criteria or the Cambridge-Hopkins questionnaire for RLS. Perceived olfactory and taste dysfunction was collected via a questionnaire. The association between RLS and perceived olfactory and taste dysfunction was assessed using logistic regression model, adjusting for potential cofounders such as age, sex, and medical history. RESULTS: RLS was associated with high odds of having perceived olfactory and/or taste dysfunction (adjusted odds ratio = 5.92, 95% confidence interval = 3.11-11.3). The significant association persisted when using the Cambridge-Hopkins questionnaire (adjusted odds ratio = 5.55, 95% confidence interval = 2.37-13.0) or when excluding participants with major chronic diseases. CONCLUSIONS: RLS was associated with increased odds of perceived olfactory and taste dysfunction.

Treatment of restless legs syndrome: Evidence-based review and implications for clinical practice (Revised 2017)§.

The objective of the current review was to update the previous evidence-based medicine review of treatments for restless legs syndrome published in 2008. All randomized, controlled trials (level I) with a high quality score published between January 2007 and January 2017 were reviewed. Forty new studies qualified for efficacy review. Pregabalin, gabapentin enacarbil, and oxycodone/naloxone, which did not appear in the previous review, have accrued data to be considered efficacious. Likewise, new data enable the modification of the level of efficacy for rotigotine from likely efficacious to efficacious. Intravenous ferric carboxymaltose and pneumatic compression devices are considered likely efficacious in idiopathic restless legs syndrome. Bupropion and clonidine were reviewed, but the lack of data determined a rating of insufficient evidence for efficacy. The following interventions continue to be considered efficacious as in 2008: levodopa, ropinirole, pramipexole, cabergoline, pergolide, and gabapentin. Bromocriptine, oxycodone, carbamazepine, and valproic acid are considered likely efficacious. Oral iron is nonefficacious in iron-sufficient subjects, but its benefit for patients with low peripheral iron status has not been adequately evaluated. Restless legs syndrome augmentation has been identified as a significant long-term treatment complication for pramipexole more than pregabalin and possibly for all dopaminergic agents more than α2δ ligands. Therefore, special monitoring for augmentation is required for all dopaminergic medications as well as tramadol. Other drugs also require special safety monitoring: cabergoline, pergolide, oxycodone, methadone, tramadol, carbamazepine, and valproic acid. Finally, we also highlighted gaps and needs for future clinical research and studies of restless legs syndrome. © 2018 International Parkinson and Movement Disorder Society.

Comparison of pregabalin with pramipexole for restless legs syndrome.

BACKGROUND: Dopaminergic medications relieve symptoms of the restless legs syndrome (RLS) but have the potential to cause iatrogenic worsening (augmentation) of RLS with long-term treatment. Pregabalin may be an effective alternative. METHODS: In this 52-week, randomized, double-blind trial, we assessed efficacy and augmentation in patients with RLS who were treated with pregabalin as compared with placebo and pramipexole. Patients were randomly assigned to receive 52 weeks of treatment with pregabalin at a dose of 300 mg per day or pramipexole at a dose of 0.25 mg or 0.5 mg per day or 12 weeks of placebo followed by 40 weeks of randomly assigned active treatment. The primary analyses involved a comparison of pregabalin and placebo over a period of 12 weeks with use of the International RLS (IRLS) Study Group Rating Scale (on which the score ranges from 0 to 40, with a higher score indicating more severe symptoms), the Clinical Global Impression of Improvement scale (which was used to assess the proportion of patients with symptoms that were "very much improved" or "much improved"), and a comparison of rates of augmentation with pregabalin and pramipexole over a period of 40 or 52 weeks of treatment. RESULTS: A total of 719 participants received daily treatment, 182 with 300 mg of pregabalin, 178 with 0.25 mg of pramipexole, 180 with 0.5 mg of pramipexole, and 179 with placebo. Over a period of 12 weeks, the improvement (reduction) in mean scores on the IRLS scale was greater, by 4.5 points, among participants receiving pregabalin than among those receiving placebo (P<0.001), and the proportion of patients with symptoms that were very much improved or much improved was also greater with pregabalin than with placebo (71.4% vs. 46.8%, P<0.001). The rate of augmentation over a period of 40 or 52 weeks was significantly lower with pregabalin than with pramipexole at a dose of 0.5 mg (2.1% vs. 7.7%, P=0.001) but not at a dose of 0.25 mg (2.1% vs. 5.3%, P=0.08). There were six cases of suicidal ideation in the group receiving pregabalin, three in the group receiving 0.25 mg of pramipexole, and two in the group receiving 0.5 mg of pramipexole. CONCLUSIONS: Pregabalin provided significantly improved treatment outcomes as compared with placebo, and augmentation rates were significantly lower with pregabalin than with 0.5 mg of pramipexole. (Funded by Pfizer; ClinicalTrials.gov number, NCT00806026.).

Association between sleeping difficulty and type 2 diabetes in women.

AIMS/HYPOTHESIS: Sleeping difficulty has been associated with type 2 diabetes in some prior studies. Whether the observed associations are independent of health behaviours, other cardiovascular risk factors or other sleep disorders is unclear. METHODS: We analysed data from 133,353 women without diabetes, cardiovascular disease and cancer at baseline in the Nurses' Health Study (NHS, 2000-2010) and the NHSII (2001-2011). Sleeping difficulty was assessed as having difficulty falling or staying asleep 'all of the time' or 'most of the time' at baseline (2000 in NHS and 2001 in NHSII). RESULTS: We documented 6,407 incident cases of type 2 diabetes during up to 10 years of follow-up. After adjustment for lifestyle factors at baseline, comparing women with and without sleeping difficulty, the multivariate-adjusted HR (95% CI) for type 2 diabetes was 1.45 (95% CI 1.33, 1.58), which changed to 1.22 (95% CI 1.12, 1.34) after further adjustment for hypertension, depression and BMI based on the updated repeated measurements. Women who reported all four sleep conditions (sleeping difficulty, frequent snoring, sleep duration ≤6 h and sleep apnoea in NHS or rotating shift work in NHSII) had more than a fourfold increased likelihood of type 2 diabetes (HR 4.17, 95% CI 2.93, 5.91). CONCLUSIONS/INTERPRETATION: Sleeping difficulty was significantly associated with type 2 diabetes. This association was partially explained by associations with hypertension, BMI and depression symptoms, and was particularly strong when combined with other sleep disorders. Our findings highlight the importance of sleep disturbance in the development and prevention of type 2 diabetes.

Rotigotine in Hemodialysis-Associated Restless Legs Syndrome: A Randomized Controlled Trial.

BACKGROUND: Restless legs syndrome (RLS) has been associated with insomnia, decreased quality of life, and increased morbidity and mortality in end-stage renal disease. This randomized controlled trial investigated effects of rotigotine in patients with RLS and end-stage renal disease. STUDY DESIGN: Double-blind placebo-controlled study. SETTING & PARTICIPANTS: Adults with moderate to severe RLS (International RLS Study Group Rating Scale [IRLS] ≥ 15) and Periodic Limb Movement Index (PLMI) ≥ 15 who were receiving thrice-weekly hemodialysis enrolled from sites in the United States and Europe. INTERVENTION: Following randomization and titration (≤21 + 3 days) to optimal-dose rotigotine (1-3mg/24 h) or placebo, patients entered a 2-week maintenance period. Polysomnography was performed at baseline and the end of maintenance. OUTCOMES & MEASUREMENTS: Primary efficacy outcome: reduction in PLMI, assessed by ratio of PLMI at end of maintenance to baseline. Secondary/other outcomes (P values exploratory) included mean changes from baseline in PLMI, IRLS, and Clinical Global Impression item 1 (CGI-1 [severity of illness]) score. RESULTS: 30 patients were randomly assigned (rotigotine, 20; placebo, 10); 25 (15; 10) completed the study with evaluable data. Mean (SD) PLMI ratio (end of maintenance to baseline) was 0.7±0.4 for rotigotine and 1.3±0.7 for placebo (analysis of covariance treatment ratio, 0.44; 95% CI, 0.22 to 0.88; P=0.02). Numerical improvements were observed with rotigotine versus placebo in IRLS and CGI-1 (least squares mean treatment differences of -6.08 [95% CI, -12.18 to 0.02; P=0.05] and -0.81 [95% CI, -1.94 to 0.33; P=0.2]). 10 of 15 rotigotine and 2 of 10 placebo patients were CGI-1 responders (≥50% improvement). Hemodialysis did not affect unconjugated rotigotine concentrations. The most common adverse events (≥2 patients) were nausea (rotigotine, 4 [20%]; placebo, 0); vomiting (3 [15%]; 0); diarrhea (1 [5%]; 2 [20%]); headache (2 [10%]; 0); dyspnea (2 [10%]; 0); and hypertension (2 [10%]; 0). LIMITATIONS: Small sample size and short duration. CONCLUSIONS: Rotigotine improved periodic limb movements and RLS symptoms in the short term among ESRD patients requiring hemodialysis in a small-scale study. No dose adjustments are necessary for hemodialysis patients.

Sleep disordered breathing and cardiovascular risk in older patients initiating dialysis in the United States: a retrospective observational study using medicare data.

BACKGROUND: Sleep disordered breathing (SDB) such as sleep apnea is associated with cardiovascular disease in the general population. However, little is known about the cardiovascular risks of SDB in patients with end-stage renal disease (ESRD). METHODS: We identified Medicare fee-for-service beneficiaries aged ≥67 years initiating dialysis between 2004 and 2009. Outcomes of interest included all-cause mortality, incident myocardial infarction, ischemic stroke, and atrial fibrillation. We compared patients with and without diagnosed SDB using Cox proportional hazards regression. RESULTS: Between 2004 and 2009, 184,217 older patients developed ESRD, of whom 15,121 (8.2 %) were previously diagnosed with SDB. Patients diagnosed with SDB were younger, more likely to be male and Caucasian, less Medicaid eligible, had more non-Nephrology clinic visits, higher body mass index, and more comorbidity. In analyses adjusting for demographics and BMI, diagnosed SDB was associated with higher risk of death and atrial fibrillation, but not associated with myocardial infarction or ischemic stroke risk. After further adjustment for all baseline characteristics, diagnosed SDB was associated with slightly lower risks of death (hazard ratio [HR]: 0.93, 95 % confidence interval [CI]: 0.91-0.96), myocardial infarction (HR: 0.92, CI: 0.87-0.98), and ischemic stroke (HR: 0.90, 95 % CI: 0.82-0.98), and not associated with atrial fibrillation (HR: 1.02, CI: 0.98-1.07). CONCLUSIONS: In older patients initiating dialysis in the U.S., diagnosed SDB was weakly associated with lower risks of death and important cardiovascular outcomes, thus adding to the list of established risk factors that are paradoxically associated with cardiovascular outcomes in the ESRD population.

Association between insomnia symptoms and mortality: a prospective study of U.S. men.

BACKGROUND: Insomnia complaints are common in older adults and may be associated with mortality risk. However, evidence regarding this association is mixed. Thus, we prospectively examined whether men with insomnia symptoms had an increased risk of mortality during 6 years of follow-up. METHODS AND RESULTS: A prospective cohort study of 23,447 US men participating in the Health Professionals Follow-Up Study and free of cancer, reported on insomnia symptoms in 2004, were followed through 2010. Deaths were identified from state vital statistic records, the National Death Index, family reports, and the postal system. We documented 2025 deaths during 6 years of follow-up (2004-2010). The multivariable-adjusted hazard ratios of total mortality were 1.25 (95% confidence interval [CI], 1.04-1.50) for difficulty initiating sleep, 1.09 (95% CI, 0.97-1.24) for difficulty maintaining sleep, 1.04 (95% CI, 0.88-1.22) for early-morning awakenings, and 1.24 (95% CI, 1.05-1.46) for nonrestorative sleep, comparing men with those symptoms most of the time with men without those symptoms, after adjusting for age, lifestyle factors, and presence of common chronic conditions. Men with difficulty initiating sleep and nonrestorative sleep most of the time had a 55% (hazard ratio, 1.55; 95% CI, 1.19-2.04; P-trend=0.01) and 32% (hazard ratio, 1.32; 95% CI, 1.02-1.72; P-trend=0.002) increased risk of cardiovascular disease mortality, respectively, relative to men without those symptoms. CONCLUSION: Some insomnia symptoms, especially difficulty initiating asleep and nonrestorative sleep, are associated with a modestly higher risk of mortality.

Clinical Efficacy and Safety of Intravenous Ferric Carboxymaltose for Treatment of Restless Legs Syndrome: A Multicenter, Randomized, Placebo-controlled Clinical Trial.

STUDY OBJECTIVES: Iron therapy is associated with improvements in restless legs syndrome (RLS). This multicenter, randomized, double-blind study evaluated the effect of intravenous ferric carboxymaltose (FCM) on RLS. METHODS: A total of 209 adult patients with a baseline International Restless Legs Syndrome (IRLS) score ≥15 were randomized (1:1) to FCM (750 mg/15 mL) or placebo on study Days 0 and 5. Ongoing RLS medication was tapered starting on Day 5, with the goal of discontinuing treatment or achieving the lowest effective dose. Co-primary efficacy endpoints were change from baseline in IRLS total score and the proportion of patients rated as much/very much improved on the Clinical Global Impression-investigator (CGI-I) scale at Day 42 in the "As-Treated" population. RESULTS: The "As-Treated" population comprised 107 FCM and 101 placebo recipients; 88 (82.2%) and 68 (67.3%), respectively, completed the Day 42 assessment. The IRLS score reduction was significantly greater with FCM versus placebo: least-squares mean (95% confidence interval [CI]) -8.0 (-9.5, -6.4) versus -4.8 (-6.4, -3.1); P = 0.0036. No significant difference was observed in the proportion of FCM (35.5%) and placebo (28.7%) recipients with a CGI-I response (odds ratio 1.37 [95% CI: 0.76, 2.47]; P = 0.2987). Fewer patients treated with FCM (32.7%) than placebo (59.4%) received RLS interventions between Day 5 and study end (P = 0.0002). FCM was well tolerated. CONCLUSION: The IRLS score improved with intravenous FCM versus placebo, although the combination of both co-primary endpoints was not met. Potential methodological problems in the study design are discussed.

Restless legs syndrome, neuroleptic-induced akathisia, and opioid-withdrawal restlessness: shared neuronal mechanisms?

Restlessness is a core symptom underlying restless legs syndrome (RLS), neuroleptic-induced akathisia, and opioid withdrawal. These three conditions also share other clinical components suggesting some overlap in their pathophysiology. Recent prospective studies demonstrate the frequent incidence of RLS-like symptoms during opioid withdrawal and supervised prescription opioid tapering. Based on the therapeutic role of µ-opioid receptor (MOR) agonists in the three clinical conditions and recent preclinical experimental data in rodents, we provide a coherent and unifying neurobiological basis for the restlessness observed in these three clinical syndromes and propose a heuristic hypothesis of a key role of the specific striatal neurons that express MORs in akathisia/restlessness.

The Role of Circadian Rhythms and Sleep in Anorexia Nervosa.

Importance: Observational studies have associated anorexia nervosa with circadian rhythms and sleep traits. However, the direction of causality and the extent of confounding by psychosocial comorbidities in these associations are unknown. Objectives: To investigate the association between anorexia nervosa and circadian and sleep traits through mendelian randomization and to test the associations between a polygenic risk score (PRS) for anorexia nervosa and sleep disorders in a clinical biobank. Design, Setting, and Participants: This genetic association study used bidirectional 2-sample mendelian randomization with summary-level genetic associations between anorexia nervosa (from the Psychiatric Genomics Consortium) and chronotype and sleep traits (primarily from the UK Biobank). The inverse-variance weighted method, in addition to other sensitivity approaches, was used. From the clinical Mass General Brigham (MGB) Biobank (n = 47 082), a PRS for anorexia nervosa was calculated for each patient and associations were tested with prevalent sleep disorders derived from electronic health records. Patients were of European ancestry. All analyses were performed between February and August 2023. Exposures: Genetic instruments for anorexia nervosa, chronotype, daytime napping, daytime sleepiness, insomnia, and sleep duration. Main Outcomes and Measures: Chronotype, sleep traits, risk of anorexia nervosa, and sleep disorders derived from a clinical biobank. Results: The anorexia nervosa genome-wide association study included 16 992 cases (87.7%-97.4% female) and 55 525 controls (49.6%-63.4% female). Genetic liability for anorexia nervosa was associated with a more morning chronotype (ß = 0.039; 95% CI, 0.006-0.072), and conversely, genetic liability for morning chronotype was associated with increased risk of anorexia nervosa (ß = 0.178; 95% CI, 0.042-0.315). Associations were robust in sensitivity and secondary analyses. Genetic liability for insomnia was associated with increased risk of anorexia nervosa (ß = 0.369; 95% CI, 0.073-0.666); however, sensitivity analyses indicated bias due to horizontal pleiotropy. The MGB Biobank analysis included 47 082 participants with a mean (SD) age of 60.4 (17.0) years and 25 318 (53.8%) were female. A PRS for anorexia nervosa was associated with organic or persistent insomnia in the MGB Biobank (odds ratio, 1.10; 95% CI, 1.03-1.17). No associations were evident for anorexia nervosa with other sleep traits. Conclusions and Relevance: The results of this study suggest that in contrast to other metabo-psychiatric diseases, anorexia nervosa is a morningness eating disorder and further corroborate findings implicating insomnia in anorexia nervosa. Future studies in diverse populations and with subtypes of anorexia nervosa are warranted.

Prospective study of restless legs syndrome and coronary heart disease among women.

BACKGROUND: Previous cross-sectional studies suggested a positive association between restless legs syndrome (RLS) and coronary heart disease (CHD). This observation was not confirmed by subsequent prospective studies. However, these prospective studies did not take into account the duration of RLS symptoms. Therefore, we prospectively examined whether RLS was associated with an increased risk of CHD in women who participated in the Nurses' Health Study, taking into account the duration of RLS symptoms. METHODS AND RESULTS: A total of 70 977 women (mean age, 67 years) who were free of CHD and stroke at baseline (2002) were followed up until 2008. Physician-diagnosed RLS was collected via questionnaire. CHD was defined as nonfatal myocardial infarction or fatal CHD. Women with RLS at baseline had a marginally higher risk of developing CHD (multivariable-adjusted hazard ratio, 1.46; 95% confidence interval, 0.97-2.18) compared with women without RLS. The risk was dependent on duration of symptoms: 0.98 (95% confidence interval, 0.44-2.19) for women with RLS for <3 years and 1.72 (95% confidence interval, 1.09-2.73) for women with RLS for ≥3 years (P trend=0.03). The multivariable-adjusted hazard ratios of women with RLS for ≥3 years were 1.80 (95% confidence interval, 1.07-3.01) for nonfatal myocardial infarction and 1.49 (95% confidence interval, 0.55-4.04) for fatal CHD relative to women without RLS. CONCLUSIONS: We observed that women with RLS for at least 3 years had an elevated risk of CHD. These results suggest that RLS or RLS-associated conditions may contribute to the origin of cardiovascular disease.

Neuroimaging studies in insomnia.

Chronic insomnia is one of the most prevalent psychiatric disorders and has a significant impact on individual's health. However, the pathophysiology of the disorder is poorly understood. The current review focuses on neuroimaging findings in insomnia. In summary, the current data suggest the following: (1) insomnia is characterized by corticolimbic overactivity during sleep and wakefulness that interferes with sleep initiation and/or maintenance; (2) insomnia patients' daytime performance is associated with a hypoactivation of task-related areas; (3) neurochemically, insomnia patients are probably characterized by reduced cortical GABA levels; (4) insomnia may be associated with abnormal brain morphometry in the frontal cortex, hippocampus and/or anterior cingulate cortex. Future investigations should include larger sample sizes or longitudinal within-subject comparisons. Other possible methodological improvements are discussed.

Prevalence of Current Restless Legs Syndrome Symptoms Among Patients Treated with Buprenorphine/Naloxone for Opioid Use Disorder.

Objective: The purpose of this study was to determine the prevalence of Restless Legs Syndrome (RLS) in patients with Opioid Use Disorder (OUD) taking buprenorphine/naloxone maintenance therapy, and to assess symptom frequency, severity, and sleep disruption due to RLS. Methods: Surveys inquired about demographic information, amount of time on maintenance treatment, previous drug use, current prescribed medications and alcohol use, and RLS symptoms. Participants were determined to have definite, probable, possible, or no RLS symptoms based on pre-established criteria from the Cambridge-Hopkins Questionnaire. Results: The sample (n=129) was 33.3% female, 81.5% white, and the mean age was 40.6 years (SD=11.9). The median duration of buprenorphine/naloxone use was 3 years. 13.2% of participants had definite/probable RLS symptoms; these symptoms tended to be of moderate severity, occur at least 5-15 times a month, and disrupt sleep to a moderate degree. Of the 17 participants with definite/probable RLS symptoms, just four were taking a medication commonly used to alleviate RLS. An additional 7.0% had possible RLS symptoms. Conclusion: Relatively high rates of current RLS symptoms were observed; the prevalence of clinically significant RLS was notably higher than that seen in the general population or in previously assessed clinical populations. RLS is common in those acutely withdrawing from opioids, and our data demonstrate that these symptoms are present in a sizable portion of patients on OUD maintenance therapy. Most patients with definite/probable current RLS symptoms did not report taking prescribed medications that have established efficacy for RLS.

Lack of Efficacy of Suvorexant in People with Insomnia and Poorly Controlled Type 2 Diabetes.

Objective/Background: Sleep disturbance is a common and underappreciated feature of diabetes and sleep may contribute to glycemic control in people with type 2 diabetes (T2D). We conducted a 3-month trial to examine the efficacy of suvorexant in improving sleep and health outcomes in people with suboptimally controlled T2D and insomnia. Participants/Methods: This parallel, double-blind, randomized placebo-controlled trial was conducted using the sequential parallel comparison design (SPCD). Sixty-nine people with poorly controlled T2D (HbA1c ≥ 6.5) were randomized to placebo and/or suvorexant (10-20 mg). The primary outcome was subjective total sleep time (sTST), and secondary outcomes were Insomnia Severity Index (ISI) score and wake time after sleep onset (WASO). Exploratory outcomes included sleep efficiency, hemoglobin A1c (HbA1c), and C-reactive protein (CRP). Exploratory analyses were conducted on relationships between sleep and diabetes outcomes. Results: There were no significant improvements in sTST (p = 0.27), ISI (p = 0.86), or WASO (p = 0.94) among participants taking suvorexant compared to placebo. There were also no significant changes in any of the exploratory endpoints. Improvements in sleep were associated with improvements in both objective (ie, HbA1c) and subjective (ie, Diabetes Distress Scale) measures of diabetes, as well as reductions in depressive symptoms, independent of treatment assignment. Conclusion: The study did not find evidence that suvorexant is efficacious for insomnia in people with poorly controlled T2D. The associations of improved sleep with improvements in both diabetes-related metrics and depressive symptoms across groups highlight the importance of identifying and treating sleeping difficulties in this population. CT Registration #: Nct03818581.