Background: The aim of the study was to demonstrate the variety of sleep di
sorders occuring in a working population in Switzerland and to estimate the
prevalence of the main sleep disorders in this Swiss cohort. We also inten
ded to demonstrate that with just a few systematic questions a straightforw
ard diagnostic workup is possible in general practice.
Methods: A questionnaire was sent to all 1473 clerks of the Berne main post
office. The questions allowed a choice between "yes" or "no", or often (=
+++), occasionally (= ++), rarely (= +) and never (= 0). Daytime sleepiness
was assessed by the Epworth Sleepiness Scale.
Results: 668 questionnaires (45%) were available for analysis. Daytime slee
piness, assessed by an Epworth score greater than or equal to 10, was found
in 13% of the respondents. Short sleep (<7 h sleep) was reported in 47%, a
nd long sleep (>9 h sleep) in 5%, of this population. Specific questions cl
early suggested obstructive sleep apnoea in 6%, restless-legs syndrome in 4
%, disorders of initiating and maintaining sleep in 19% and narcolepsy in 0
.5% of respondents.
Conclusion: Chronic sleep insufficiency and sleep complaints appear to be f
requent in this relatively young Swiss working population. The questionnair
e-based estimated prevalence of the main sleep disorders is comparable to p
reviously published international data.