Sleep disordered breathing at work : Cause and effects

Abstract: The recent discovery of obstructive sleep apnea syndrome (OSAS) as a prevalent disorder has highlightedthe fact that snoring is not just a harmless noise. Snoring and OSAS in the work milieu has hardly beeninvestigated, which makes it important to identify both risk factors and consequences in the work place.Two different studies were undertaken to investigate whether occupational exposure to organicsolvents might be an independent risk factor in causing both snoring and OSAS. In two other studies theeffects on subjective work performance from snoring and OSAS, and the occurence of occupationalaccidents of traumatic origin among patients with sleep disordered breathing (SDB) were investigated.Among 66 male patients from Dalacarlia county, occupationally exposed to solvents and referred tothe Department of Occupational and Environmental Medicine, University Hospital, Uppsala, between1984 and 1988, a prevalence of 19.7% of OSAS was conservatively estimated, giving a relative riskestimate of 15.2 (95% CI 10.4-27.7).A questionnaire was used to investigate whether patients with OSAS and snoring are more frequentlyexposed to organic solvents during work than the general population. Men with OSAS or snoring, andwomen with snoring had more often been occupationally exposed to organic solvents than the samplefrom the general population, showing an almost twofold increase in risk for those exposed during wholeworking days. For men, the risk of OSAS or snoring increased with increasing exposure.The same questionnaire was used to evaluate the frequency of subjective excessive daytime sleepinessat work and self perceived work performance among males suffering from heavy snoring and OSAS. Theodds ratios for reporting sleepiness at work were thirtyfold for OSAS patients and tenfold for heavysnorers as compared to the referents. Patients with OSAS and snoring also both showed an increased oddsratios on measures of difficulties with concentration, learning new tasks and performing monotonoustasks when compared to the referent group. Snoring males in the population also had more problems withself-perceived sleepiness at work than nonsnoring man.A ten-year retrospective investigation of reported traumatic occupational injuries among patients withSDB was performed. The risk of being involved in an occupational accident related to inattention wasabout twofold among male heavy snorers and increased by 50% among males suffering from OSAS. Forfemales, the risk increased by at least threefold among heavy snorers and OSAS patients. Reducedvigilance and attention often seen among patients with SDB are the proposed mechanisms for the results.In conclusion, the results in this thesis give further support that exposure to organic solvents is a riskfactor for both snoring and OSAS. Sleep disordered breathing may impair subjective work performance,and increase proneness of being involved in occupational accidents.