Excessive daytime sleepiness: a 1-year study in an unselected inpatient population.

A prospective epidemiological investigation of excessive daytime sleepiness (EDS) was carried out in an unselected inpatient population admitted to a general hospital during a 1-year period. The study comprised 2518 patients, 1347 female and 1171 male, aged 6-92 years (mean, 55.2). On the basis of histories and clinical and polysomnographic data, EDS was found in 28 cases (1.11%). Of these, 25 (0.99%; 18 female and 7 male; mean age, 61.3) had sleep apnea syndromes (SAS) with predominantly obstructive apnea. Two patients (0.07%; one female and one male; mean age, 65.5) had idiopathic CNS hypersomnia, and one male patient (0.03%) aged 48 years had a combination of narcolepsy and SAS. Differences and agreements of our findings with previous literature data are discussed. The present study shows that in an unselected inpatient population, EDS is a relatively common sleep disorder, usually found in mild to moderate forms. Because it is not severe, it disturbs only relatively domestic activities of elderly retired patients or others who do not work outside the home, and is often masked by other troubles. For these reasons, EDS in the aging population may pass unnoticed in epidemiological studies based only on data from sleep disorder centers.