The relative influence of hypoxemia versus hypersomnolence on the behavioral morbidity of sleep apnea

Martha Jane Merrion, Purdue University

Abstract

To evaluate the effect of hypersomnolence and hypoxemia on neuropsychological performance in sleep apnea male patients, 75 subjects (25 males with sleep apnea-OSAS, 26 males with insufficient sleep-IS, and 24 males with chronic obstructive pulmonary disease-COPD) were evaluated with nocturnal polysomnography, the Multiple Sleep Latency Test (MSLT), and neuropsychological testing. Although it was predicted that sleepiness versus hypoxemia would correlate positively with the cognitive deficit found in sleep apnea, it was found that neither sleepiness nor hypoxemia correlated in the expected direction with overall performance in any of the three diagnostic groups. The COPD patients demonstrated the greatest number of tests impaired and the greatest degree of deficit, while OSAS patients exhibited somewhat less impairment. Both groups were found to be mildly impaired on a measure comprised of scaled scores representing overall cognitive decline. The IS group was found to be within the normal range on this variable. It was proposed that the results suggest a profile of impairment, with the COPD and OSAS subjects demonstrating deficits on measures purportedly sensitive to both hypoxemia and sleepiness. While the COPD subjects clearly were more impaired relative to OSAS and IS patients on the tests hypothetically sensitive to hypoxemia, as well as on tests of memory, the results using tests purportedly sensitive to sleepiness were mixed between the COPD and OSAS groups with the OSAS group perhaps demonstrating the greater relative impairment. The results were further discussed with reference to the confounds of age, education, chronic illness, and poly-drug therapy as possible influences on subject performance.

Degree

Ph.D.

Advisors

Tiffany, Purdue University.

Subject Area

Psychotherapy

COinS