Validation of the Essener Questionnaire of Age and Sleepiness in the elderly using pupillometry

In the elderly population, daytime sleepiness (DS) is a burden that affects quality of life, cognitive and physical functioning as well as health status and morbidity. The measurement of DS in older subjects continues to be a challenge, as there are only few elderly-specific assessment tools available. Therefore, we compared the newly developed Essener Questionnaire of Age and Sleepiness (EQAS) with pupillography, a physiological measure of sleepiness. The aim was to identify EQAS cut-off values for increased daytime sleepiness. For the validation study, we determined EQAS scores and the pupillary unrest index (PUI) of the pupillographic sleepiness test (PST) in 88 geriatric in-patients. We also collected data on age, gender, co-morbidities, and geriatric assessment in these subjects. Of all included patients 37 (42%) completed the PST. Fourteen (16%) subjects refused to participate and 37 (42%) subjects could not complete 11 min required for a valid PUI. Subjects with complete and incomplete pupillometry did not differ in basic assessment parameters of health status or cognitive functioning. EQAS scores correlated significantly with PUI values (r = 0.70; p < 0.001) demonstrating a dose-response relationship. Based on ROC analysis, an EQAS score above 3 was optimal to distinguished sleepy from non-sleepy participants with sensitivity of 67%, specificity of 93% and positive and negative predictive values of 75% and 90%, respectively. In conclusion, the high negative and positive predictive values of the EQAS indicate that this instrument is a useful and valid assessment tool for daytime sleepiness in the elderly. The easy administration of this observational instrument favors its adoption in geriatric medicine.