This study was designed to evaluate the prevalence and consequences of sleepiness and sleep disorders after traumatic brain injury (TBI).
Subjects over 18 years old with TBI, at least 3 months post brain injury, were prospectively recruited and underwent physical examination, nocturnal polysomnography (NPSG), multiple sleep latency test (MSLT) and neuropsychological testing. The latter was done on all patients at the same time of day (after the 2nd MSLT nap) and consisted of Psychomotor Vigilance Test (PVT), Profile of Mood States (POMS) and Functional Outcome of Sleep Questionnaire (FOSQ).
Of the 87 patients who completed the protocol, there were 24 women (28%) and 63 men (72%) with an average age of 38.3 ± 15.2 (SD) years. Forty one subjects (47%) had abnormal sleep studies. Nineteen patients (22%) were diagnosed with obstructive sleep apnea (OSA), 10 (15%) had posttraumatic hypersomnia (PTH), 6 (7%) had narcolepsy and 6 (7%) had periodic limb moovements in sleep (PLM). Twenty three subjects (23.4%) were categorized as objectively sleepy on the basis of MSLT score < 10 minutes. There were no differences between the sleepy and non-sleepy subjects in age, race, gender, education, GCS scores, cause of injury, CT findings, injury severity or months post injury. Sleepy patients had a greater body mass index (BMI) than the non-sleepy (p = 0.01). Obese patients (BMI ≥ 30) were more likely to have OSA (p < 0.0001). Sleepy subjects had slower fastest reaction times (p < 0.05), slower slow reaction times (p < 0.05)and more lapses (p < 0.05)on PVT. PMS did not differ significantly. Sleepy patients had higher FOSQ scores (p < 0.05), indicating better quality of life.
Almost half (47%) of an unselected TBI population can be expected to have a sleep disorder with OSA being the most common (22%), followed by PTH (15%). Sleepy TBI patients have impaired cognitive functioning and PVT performance, but may be unaware of problems.
All TBI patients should be evaluated for sleep disorders with NPSG and MSLT.
Richard Castriotta, Grant monies (from industry related sources) Cephalon, Inc. contributed to the funding of this research.; Consultant fee, speaker bureau, advisory committee, etc. I have spoken at conferences sponsored by Cephalon