Prevalence of restless legs syndrome and sleep problems in Korean children and adolescents with attention deficit hyperactivity disorder: a single institution study

Restless Legs Syndrome in Children and Adolescents

Children with psychiatric comorbidities frequently are referred for evaluation of sleep complaints. Common sleep symptoms can include difficulty falling asleep, frequent nocturnal awakening, restless sleep, and symptoms of restless legs syndrome (RLS). The understanding of the sleep condition in relation to the psychiatric comorbidity often is a challenge to the physician and often sleep disorders remain undiagnosed, untreated, or undertreated. Restless legs syndrome has been associated with psychiatric comorbidities and with certain medications, such as antidepressants, antihistamines, and antipsychotics. This article reviews the presentation of RLS and restless sleep, the association with psychiatric comorbidities, and treatment options.

Attention deficit hyperactivity disorder and restless leg syndrome across the lifespan: A systematic review and meta-analysis

This systematic review aims to assess the association between attention deficit hyperactivity disorder (ADHD) and restless legs syndrome (RLS) in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Databases were searched for original articles that reported prevalence data on ADHD and RLS until January 24th, 2023. Two independent reviewers evaluated the quality of the articles using the National Institutes of Health assessment tool. Among the 208 articles identified between 1996 and 2022, 29 were included. In large general population studies, 2.6-15.3% of participants met the RLS criteria, of which 3.2-17.4% presented with ADHD. In the ADHD group, RLS symptoms ranged from 11 to 42.9% in children and 20-33.0% in adults. This suggests a strong co-occurrence between RLS and ADHD. A common characteristic of these conditions is sleep fragmentation, as discussed in the reviewed papers. Although large-scale studies with comparable diagnostic criteria across the lifespan are required, our findings may advocate a possible common physiological pathway, including sleep fragmentation and dopaminergic system impairment.

A Systematic Review of Sleep and Circadian Rhythms in Children with Attention Deficit Hyperactivity Disorder

OBJECTIVE

Children and adults with ADHD often report sleep disturbances that may form part of the etiology and/or symptomatology of ADHD. We review the evidence for sleep changes in children with ADHD.

METHODS

Systematic review with narrative synthesis assessing sleep and circadian function in children aged 5 to 13 years old with a diagnosis of ADHD.

RESULTS

148 studies were included for review, incorporating data from 42,353 children. We found that sleep disturbances in ADHD are common and that they may worsen behavioral outcomes; moreover, sleep interventions may improve ADHD symptoms, and pharmacotherapy for ADHD may impact sleep.

CONCLUSION

Sleep disturbance may represent a clinically important feature of ADHD in children, which might be therapeutically targeted in a useful way. There are a number of important gaps in the literature. We set out a manifesto for future research in the area of sleep, circadian rhythms, and ADHD.

Restless Legs Syndrome in Children and Adolescents

Children with psychiatric comorbidities frequently are referred for evaluation of sleep complaints. Common sleep symptoms can include difficulty falling asleep, frequent nocturnal awakening, restless sleep, and symptoms of restless legs syndrome (RLS). The understanding of the sleep condition in relation to the psychiatric comorbidity often is a challenge to the physician and often sleep disorders remain undiagnosed, untreated, or undertreated. Restless legs syndrome has been associated with psychiatric comorbidities and with certain medications, such as antidepressants, antihistamines, and antipsychotics. This article reviews the presentation of RLS and restless sleep, the association with psychiatric comorbidities, and treatment options.

Restless legs syndrome and iron deficiency in adults with attention-deficit/hyperactivity disorder

STUDY OBJECTIVE

The association between restless legs syndrome (RLS), periodic leg movements during sleep (PLMS) and iron deficiency has been reported in children with attention-deficit/hyperactivity disorder (ADHD); however little is known in adults. The aim of this study was to assess frequencies of RLS, PLMS and other leg movements (LM) and iron deficiency and their relationships with ADHD phenotype in adults with ADHD.

METHODS

Two hundred adults with ADHD (112 males, median age 31 years) were evaluated on lifetime ADHD symptoms and sleep characteristics. RLS was diagnosed according to standard criteria. Serum ferritin levels were measured, with iron deficiency defined as <50 ng/mL. A subgroup of 48 ADHD patients with RLS, 48 ADHD without RLS and 48 controls underwent a polysomnography to record sleep, LM, and PLMS.

RESULTS

RLS was diagnosed in 33.0%, associated with earlier onset of ADHD, hyperactive presentation and more severe lifetime ADHD symptoms. Iron deficiency was found in 35.5% with higher frequency in patients with RLS. LM were more frequent in ADHD patients, with higher LM periodicity levels in those with comorbid RLS in comparison to controls. However, PLMS index did not differ between groups. Patients with ADHD and RLS had higher frequency of iron deficiency than other groups.

CONCLUSIONS

In a large sample of adults with ADHD, we individualized a subgroup characterized by earlier and severe ADHD symptoms, RLS, higher LM during sleep and iron deficiency. This endophenotype may reflect a different neurobiological mechanism that remains to be further studied.

Sleep problems increase the risk of musculoskeletal pain in boys but not girls: a prospective cohort study

Adults with sleep problems are at higher risk for onset of musculoskeletal pain, but the evidence is less clear for children. This prospective cohort study investigated whether children with sleep problems are at higher risk for onset of musculoskeletal pain and explored whether sex is a modifier of this association. In a prospective cohort study of Australian schoolchildren (n = 1239, mean age 9 years), the associations between sleep problems at baseline and new onset of both musculoskeletal pain and persistent musculoskeletal pain (pain lasting > 3 months) 1 year later were investigated using logistic regression. The potential modifying effect of sex was also assessed. One-year incidence proportion for musculoskeletal pain onset is 43% and 7% for persistent musculoskeletal pain. Sleep problems were associated with musculoskeletal pain onset and persistent musculoskeletal pain onset in boys, odds ratio 2.80 (95% CI 1.39, 5.62) and OR 3.70 (1.30, 10.54), respectively, but not girls OR 0.58 (0.28, 1.19) and OR 1.43 (0.41, 4.95), respectively.Conclusions: Rates of musculoskeletal pain are high in children. Boys with sleep problems are at greater risk of onset of musculoskeletal pain, but girls do not appear to have higher risk. Consideration of sleep health may help prevent persistent musculoskeletal pain in children. What is Known: • Sleep problems are associated with the onset of musculoskeletal pain in adults. • It is not clear if the association between sleep problems and the onset of musculoskeletal pain is present also in children and if sex plays a role in this association. What is New: • This is the first large population-based study that has prospectively investigated the relationship between sleep problems and onset of musculoskeletal pain in school-aged children. • Children, especially boys with sleep problems, were at increased risk for the development of persistent musculoskeletal pain.

Prevalence and Clinical Characteristics of the Restless Legs Syndrome (RLS) in Patients Diagnosed with Attention-Deficit Hyperactivity Disorder (ADHD) in Antioquia

Introduction:

Attention Deficit Hyperactivity Disorder (ADHD) is the most common behavioral issue for children. One of the sleeping disorders most frequently related to ADHD is the Restless Legs Syndrome (RLS), characterized by an irresistible urge to move the legs, something that is generally associated with paresthesias and motor restlessness. The prevalence rate of RLS in children diagnosed with ADHD is close to 18%, but in Colombia, these cases have been hardly studied.

Objective:

To determine the frequency of RLS, in children with ADHD.

Methods:

A cross-sectional study, filled out by parents of children diagnosed with ADHD, were analyzed. This questionnaire contained clinical criteria for classifying ADHD according to the DSM-IV, as well as diagnostic criteria for RLS by the National Institutes of Health (2003).

Results:

A predominance rate of 65.6% in combined ADHD was observed in children with RLS criteria. Upon carrying out an exploratory data analysis, it was found that having a family history of RLS and belonging to the middle or low socioeconomic strata are conditions associated with the presence of RLS in children with ADHD, with a significant p (p < 0.000) and a PR of 4.47 (3.16-6.32).

Conclusions:

The prevalence of RLS was similar to the findings of other clinical investigations. However, it highlights new prevalence values in relation to the comorbidity between ADHD and RLS, suggesting the need for new clinical and therapeutic alternatives amidst the presence of both syndromes.

Prevalence of Restless Legs Syndrome in Adult ADHD and Its Subtypes

In this observational cross-sectional study, 49 subjects were assessed for sleep disorders and for ADHD symptoms. Thirty-six received an ADHD diagnosis (29: combined type (ADHD-C); 7: inattentive type). An RLS and RLS symptoms prevalence of 34.5% was found, with a higher prevalence rate in the ADHD-C subgroup, although not significantly (p = 0.066). RLS symptoms were correlated with particularly hyperactivity-impulsivity (ρ = 0.742; p: 0.000). ADHD patients with positive RLS scores reported higher scores on the ADHD-Rating scale compared with patients with negative RLS scores (Z: -2.968, p = 0.003), mainly due to higher hyperactivity-impulsivity scores (Z: -3.145; p = 0.002). Our findings show that clinicians need to be aware of RLS among adult ADHD patients, particularly those with severe hyperactivity-impulsivity symptoms.

Sleep Difficulties are Associated with Parent Report of Sluggish Cognitive Tempo

OBJECTIVE

Sleep disturbance is considered both a behavioral symptom of and a contributor to functional difficulties in children with attention-deficit/hyperactivity disorder (ADHD). The construct of sluggish cognitive tempo (SCT) has also been linked to ADHD; however, little is known regarding the effects of sleep specifically on SCT symptoms. This study examined the association between parent-reported sleep disturbance and parent- and teacher-reported SCT, while controlling for the effects of ADHD and mood symptoms.

METHOD

Participants included 746 clinically referred children (65% male, age range: 5-18 years) with both parent and teacher ratings assessing symptoms of ADHD, mood symptoms (depression, anxiety), and SCT. Parents/caregivers also rated their child's sleep problems with regard to 4 core concerns: falling asleep, sleep restlessness, difficulty waking, and breathing difficulties. The SCT scale included three empirically derived subscales: sleepy/sluggish, low initiation/persistence, and daydreamy.

RESULTS

After accounting for age, medication status, ADHD symptoms, depressive symptoms, and anxiety, sleep problems accounted for a small but significant proportion of additional variance in the prediction of parent-reported sleepy/sluggish SCT. Difficulty waking showed the strongest associations with parent-reported SCT. There were no significant relationships found between parent-reported sleep difficulties and teacher-reported SCT.

CONCLUSIONS

Some elements of sluggishness and lethargy inherent to the SCT construct may be associated with sleep difficulties, even after accounting for ADHD and mood symptoms; however, these associations are not consistent across SCT subscales and sleep problem domains.