Abstract
The aim of our study was to investigate age-related changes in sleepiness symptoms associated with sleep disordered breathing (SDB).
Wisconsin Sleep Cohort participants were assessed using polysomnography, the Epworth Sleepiness Scale (ESS) and the multiple sleep latency test (MSLT). SDB was defined as an apnoea/hypopnoea index ≥15 events·h−1, and sleepiness as ESS ≥10 and MSLT ≤5 min. Odds ratios were calculated using generalised estimating equations associating sleepiness with SDB, and conditional logistic regression examining changes in longitudinal sleepiness status (ESS only). Models were a priori stratified by sex.
ESS was measured in 1,281 participants and MSLT in 998 at multiple time-points (ESS n=3,695; MSLT n=1,846). Significant interactions were found between SDB and age in males, but not females. The odds ratios modelled for sleepiness in a 40-yr-old male with SDB were significant compared to a male without SDB (ESS 2.1 and MSLT 2.9); however, these associations were not significant at 60 yrs of age. The within-subject odds ratio for sleepiness was also significant at 40 yrs of age (OR 3.4), but not at 60 yrs of age.
The age-related reductions in the association between sleepiness and SDB may have clinical implications for the diagnosis and treatment of SDB in older people as sleepiness is often used as a therapeutic target.
Footnotes
Support Statement
This study was supported by the US National Institute of Health (grants R01HL62252, R01AG14124, RR03186 and 1UL1RR025011). A. McMillan was funded by a National Institute of Health research grant. The study was supported by the NIHR Respiratory Disease Biomedical Research Unit at the Royal Brompton and Harefield NHS Foundation Trust and Imperial College London (London, UK).
Statement of Interest
Statements of interest for M.J. Morrell and L. Finn can be found at www.erj.ersjournals.com/site/misc/statements.xhtml
- Received October 12, 2011.
- Accepted December 10, 2011.
- ©ERS 2012