Yamamoto K, Kobayashi F, Hori R, Arita A, Sasanabe R, Shiomi T. Association between pupillometric sleepiness measures and sleep latency derived by MSLT in clinically sleepy patients.
Environ Health Prev Med 2013;
18:361-7. [PMID:
23420264 PMCID:
PMC3773097 DOI:
10.1007/s12199-013-0331-0]
[Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Accepted: 01/30/2013] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVES
The multiple sleep latency test (MSLT) has been employed extensively in clinical and research settings as a gold standard for objectively measuring sleepiness. In a general population or in a variety of work settings, however, a more convenient, rapidly administered measuring method is preferable. We examined the potential utility of pupillometry by comparing its objective measures, pupillary unrest index (PUI) and relative pupillary unrest index (RPUI), with MSLT-derived sleep latency (SL).
METHODS
The study cohort comprised 45 patients (39 males, 6 females, mean age 38.9 ± 11.3 years) referred to the Sleep Disorders Center for the two-nap SL test. SL was measured twice before noon, and pupillometric measurement was performed immediately before each SL test. Subjective sleepiness was measured by using the Epworth Sleepiness Scale (ESS).
RESULTS
The association between PUI and SL was significant and far closer than that between RPUI and SL. A significant difference was observed between the two groups, based on each subject's experience of drowsy driving accidents over the past 3 years in the PUI and RPUI, as well as in SL. The subjective sleepiness measure, ESS, did not relate to any other physiological sleepiness measures.
CONCLUSIONS
In our study cohort, the pupillometric sleepiness measure, PUI, was significantly correlated with, and behaved in a manner equivalent to, MSLT-derived SL in clinically sleepy patients. However, several points remain to be carefully examined before applying pupillometry for screening sleepiness in a general population, or in occupational settings.
Collapse