Differential sleep, sleepiness, and neurophysiology in the insomnia phenotypes of shift work disorder.
Sleep
; 38(1): 119-26, 2015 Jan 01.
Article
en En
| MEDLINE
| ID: mdl-25325466
ABSTRACT
STUDY OBJECTIVES:
To characterize and compare insomnia symptoms within two common phenotypes of Shift Work Disorder.DESIGN:
Observational laboratory and field study.SETTING:
Hospital sleep center.PARTICIPANTS:
34 permanent night workers. Subjects were classified by Epworth Sleepiness Scale and Insomnia Severity Index into 3 subgroups asymptomatic controls, alert insomniacs (AI), and sleepy insomniacs (SI). MEASUREMENTS Sleep parameters were assessed by sleep diary. Circadian phase was evaluated by dim-light salivary melatonin onset (DLMO). Objective sleepiness was measured using the multiple sleep latency test (MSLT). Brain activity was measured using the N1 event-related potential (ERP). A tandem repeat in PER3 was genotyped from saliva DNA.RESULTS:
(1) AI group showed normal MSLT scores but elevated N1 amplitudes indicating cortical hyperarousal. (2) SI group showed pathologically low MSLT scores but normal N1 amplitudes. (3) AI and SI groups were not significantly different from one another in circadian phase, while controls were significantly phase-delayed relative to both SWD groups. (4) AI showed significantly longer sleep latencies and lower sleep efficiency than controls during both nocturnal and diurnal sleep. SI significantly differed from controls in nocturnal sleep parameters, but differences during diurnal sleep periods were smaller and not statistically significant. (5) Genotype × phenotype χ² analysis showed significant differences in the PER3 VNTR 9 of 10 shift workers reporting sleepiness in a post hoc genetic substudy were found to carry the long tandem repeat on PER3, while 4 of 14 shift workers without excessive sleepiness carried the long allele.CONCLUSIONS:
Our results suggest that the sleepy insomnia phenotype is comprehensively explained by circadian misalignment, while the alert insomnia phenotype resembles an insomnia disorder precipitated by shift work.Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Fenotipo
/
Fases del Sueño
/
Trastornos del Sueño del Ritmo Circadiano
/
Trastornos del Inicio y del Mantenimiento del Sueño
Tipo de estudio:
Observational_studies
/
Risk_factors_studies
Límite:
Female
/
Humans
/
Male
Idioma:
En
Revista:
Sleep
Año:
2015
Tipo del documento:
Article
Pais de publicación:
EEUU
/
ESTADOS UNIDOS
/
ESTADOS UNIDOS DA AMERICA
/
EUA
/
UNITED STATES
/
UNITED STATES OF AMERICA
/
US
/
USA