Health-related quality of life in Italian patients with narcolepsy: the SF-36 health survey.
OBJECTIVE
To evaluate the psychometric performances of the 36-item short form (SF-36), a tool measuring health-related quality of life (HRQoL) in patients with narcolepsy or other sleep disorders, presenting excessive daytime sleepiness (EDS) as the main symptom. To compare the HRQoL of patients with narcolepsy with the Italian norm. To disclose the clinical predictors influencing the HRQoL.


METHODS
One hundred and eight adults with narcolepsy, 115 with obstructive sleep apnea syndrome (OSAS) and 42 with idiopathic hypersomnia (IH) enrolled for a multicentric cross-section study employing self-administered questionnaires investigating the HRQoL (SF-36), EDS and cataplexy. A psychometric analysis and the standardized scoring of the 8 scales of the SF-36 were performed. The correlation between SF-36 scales and clinical features of narcolepsy was measured by a multiple linear regression analysis.


RESULTS
SF-36 satisfied the recommended psychometric standards. Patients with narcolepsy had all domains except Bodily Pain lower than the Italian norm. Some of the variance of Physical Functioning (R(2) 0.07), Role functioning-Physical (R(2) 0.31), General Health (R(2) 0.15), Vitality (R(2) 0.10), Social Functioning (R(2) 0.21) and Role functioning-Emotional (R(2) 0.15) was explained both by EDS (inverse correlation) and disease duration (direct correlation).


CONCLUSIONS
The SF-36 form is a reliable outcome measure for hypersomniac disorders. Narcolepsy seriously impacts patients' HRQoL in terms of physical and mental well-being and impairs physical and emotional functions, restricting social life. EDS is the main symptom determining this impairment. However, disease duration plays a role in counterbalancing this feature, probably by means of adaptation.
Vignatelli
Luca
L
Dipartimento di Scienze Neurologiche, Università degli Studi di Bologna, Via Ugo Foscolo 7, 40123 Bologna, Italy.
D'Alessandro
Roberto
R
Mosconi
Paola
P
Ferini-Strambi
Luigi
L
Guidolin
Loredana
L
De Vincentiis
Armando
A
Plazzi
Giuseppe
G
D000203:Activities of Daily Living / Q000523:psychology; D000293:Adolescent; D000328:Adult; D000368:Aged; D001294:Attitude to Health; D002385:Cataplexy / Q000523:psychology; D003430:Cross-Sectional Studies; D006970:Disorders of Excessive Somnolence / Q000523:psychology; D005260:Female; D006306:Health Surveys; D006801:Humans; D007558:Italy; D008297:Male; D008875:Middle Aged; D009290:Narcolepsy / Q000523:psychology*; D011594:Psychometrics / Q000706:statistics & numerical data; D011788:Quality of Life / Q000523:psychology*; D015203:Reproducibility of Results; D020181:Sleep Apnea, Obstructive / Q000523:psychology; D012917:Social Adjustment; D011795:Surveys and Questionnaires