Nocturnal movements in children with atopic dermatitis have a timing pattern: A case-control study

Abstract

Nocturnal atopic dermatitis (AD) flares affect over 60% of children with AD, and are associated with sleep disturbance. 1,2 Little is known about the underlying rhythm of these highly pruritic flares, and whether treatment with sedating antihistamines alters nocturnal motor activity due to itch. 1,3 We hypothesized that nighttime scratching in AD has a rhythm. To evaluate our hypothesis, we performed a case-control study with children aged 6-17 years with moderate/severe AD and healthy age/gender matched controls. Demographic details of the study population have been published. 4 Participants were 65% male, mean age±standard deviation (SD) 11.0±3.2 years in AD (n=20) versus controls (n=20)11.5±3.3(p=0.68). Moderate/severe AD was defined by a SCORing Atopic Dermatitis (SCORAD) score >25, our patients ranged from 28-92, µ±SD=42±17. Disease severity (SCORAD) correlated with Wake After Sleep Onset (WASO), r (spearman) =0.61, p<0.01, n=19.

Timing of scratch and limb movements during sleep in children with atopic dermatitis

“…Patients with more severe disease were on antihistamine medication, which is a potential confounder to these findings. However, our previous work with actigraphy in AD patients off antihistamines demonstrated a similar timing effect 4 . In addition to the small sample size, another limitation to our study was that the software was unable to attribute arousals to scratch versus not scratch events.…”

“…However, our previous work with actigraphy in AD patients off antihistamines demonstrated a similar timing effect. 4 In addition to the small sample size, another limitation to our study was that the software was unable to attribute arousals to scratch versus not scratch events. Subjectively we noted arousals appeared to occur both before and after scratch events.…”

“…Children with atopic dermatitis (AD) experience significant sleep disruption, 1,2 in part due to the vicious itch-scratch cycle, with an estimated 3 million school-aged children in the US impacted. 3 Outpatient actigraphy studies in AD identified that children have a timing pattern to limb movements, 4 and inpatient studies identified this pattern is different than in other sensory motor conditions during sleep, such as periodic limb movement disorder (PLMD). 5 However, the timing of nocturnal atopic dermatitis limb movements has not been evaluated to decipher whether movements are due solely to scratch.…”

Circadian disruption and human health

“…Allergic rhinitis symptoms peak between 4 and 6 am, a time when pollen counts are high; patient is recumbent (sleeping); and when inflammatory rhythms are upregulated -all of which can increase edema of the upper airway (227). Atopic dermatitis (eczema) symptoms also appear to peak in the evening, with overnight scratching peaking approximately 3 hours after bedtime (236).…”