Periodic limb movements and restless legs syndrome in children with a history of prematurity

Abstract

Introduction Little is known about which children are at increased risk for restless legs syndrome (RLS) and periodic limb movement disorder (PLMD). Polysomnographic data from the Caffeine for Apnea of Prematurity-Sleep (CAPS) study showed a high prevalence of elevated periodic limb movement index in a cohort of ex-preterm children, but the clinical importance of this finding, such as association with RLS, is unknown. We hypothesized that ex-preterm children would have a high prevalence of RLS and PLMD. Methods Ex-preterm children enrolled in CAPS, now aged 5-12 years, completed home polysomnography and standardized questionnaires. A diagnosis of RLS or PLMD was established by participants meeting the International Classification of Sleep Disorders, 3rd edition criteria based on questionnaires and polysomnograms. Clinically available serum ferritin levels were assessed. Results 167 participants underwent polysomnography and completed all questionnaires. The overall prevalence of RLS was 14/167 (8.4%). An additional 13 subjects (7.8%) were found to have PLMD. Of the 26 participants who had >5 periodic limb movements/hour, 7 (26.9%) had RLS and 13 (50%) had PLMD. Serum ferritin levels were <50 mcg/L (range 11 to 38.4) for all 8 participants referred for testing. Conclusions Children with a history of prematurity have a high prevalence of RLS, particularly those with elevated periodic limb movements. Iron deficiency likely contributes to RLS and PLMD symptoms in this population. Clinicians evaluating ex-preterm children with sleep disturbances should evaluate for RLS and PLMD. Further studies including serum ferritin evaluation are needed to confirm these findings.

Efectos fisiológicos y cognitivos de la cafeína en la infancia: Revisión sistemática de la literatura

“…En el mismo orden de ideas, Watson et al 45 reportaron que el alcaloide podría estar directamente relacionado con trastornos del sueño, como el insomnio. No obstante, Cielo et al 46 indicaron que la cafeína no eleva la incidencia de otro tipo de trastornos del sueño, particularmente del síndrome de piernas inquietas (SPI).…”

“…De las 20 investigaciones analizadas 16 tuvieron una calificación de calidad fuerte. Las cuatro restantes 45,46,50,53 lograron una calificación moderada. Dos de estos estudios 45,46 corresponden a los efectos fisiológicos, uno 50 versa sobre los efectos cognitivos de la cafeína, y uno más 53 trata sobre los efectos del alcaloide en los trastornos paidopsiquiátricos.…”

Long-Term Healthcare Outcomes of Preterm Birth: An Executive Summary of a Conference Sponsored by the National Institutes of Health

“…44 Children born preterm also have a higher prevalence of periodic limb movements, which may disrupt their sleep. 47 However, there is no clear understanding of the mechanistic roles of ventilatory-control abnormalities, upper airway muscle hypotonia, palatal deformation (owing to prolonged neonatal endotracheal intubation), adenotonsillar hypertrophy, and obesity in causing sleep-related disturbances. The causes and mechanisms for these conditions during childhood and adolescence remain to be addressed.…”

Restless Legs Syndrome and Periodic Limb Movement Disorder in Children

“…Only half of the studies listed reported a diagnosis of PLMD which was based either on parental report 31 or the current ICSD criteria at publication time. 14,34 Considering these caveats, and using current diagnostic criteria, clinically significant PLMD in children is probably even less common than currently assumed. Periodic limb movement disorder tends to run in families.…”