Effect of amantadine on the sleep-wake cycle of an inpatient with brain injury.

BACKGROUND: A previous study suggested that the routine use of drugs intended to improve attention and arousal, such as methylphenidate, tend to have a variable but not significant effect on sleep-wake cycles. As amantadine is a frequently employed drug in brain injury rehabilitation, with known effects on fatigue and motor processing speed, this study examined the effect of amantadine on the sleep-wake behaviour of patients with brain injury undergoing rehabilitation. METHOD: This was a naturalistic observation using an observationally defined sleep-wake distribution for a total of 43 subjects with brain injury. Identified patients were observed for a full 24 hours a day 2 weeks before and 2 weeks after starting amantadine. Some of these patients (n = 12) had been administered amantadine on clinical grounds and, for this paper, served as the experimental group, while the drug naive (n = 31) served as a control. Three outcome measures were operationalized: hours of sleep in 24 hours, hours of sleep during daytime and hours of sleep during night-time. RESULT: The average number of hours of sleep during a 24-hour period was not significantly different for the two cohorts. Similarly hours of sleep during daytime and hours of sleep during night-time were on average the same for the two groups. The data suggest that amantadine has no direct bearing on sleep/wake cycles using these parameters. CONCLUSION: This study fails to demonstrate that the use of amantadine on an inpatient brain injury population will affect sleep/wake quantity.

The role of serum testosterone and TBI in the in-patient rehabilitation setting.

OBJECTIVES: To explore the relationship between serum testosterone levels, age, length of stay, admission, discharge and changes in functional capacity over time among patients with traumatic brain injury treated in a rehabilitation hospital. DESIGN: This study used a nonrandomized chart review of 54 males, consecutively admitted to a brain injury rehabilitation hospital. METHODS: The charts of 54 males consecutively admitted to a brain injury rehabilitation unit between the periods of December 2004 and May 2005 were included in this study. Individuals were included in this study if they were 18 years of age or older, had suffered a traumatic brain injury, undergone admission and discharge, functional independence measure (FIM) testing and had received a serum testosterone level check within one to seven days from admission. MAIN OUTCOME AND RESULTS: The main outcome measure of this study was the FIM changes over time, as compared with admission testosterone levels. Low serum testosterone levels on admission to the in-patient rehabilitation unit were associated with longer lengths of stay, lower average admission FIM scores, less improvement in FIM scores, and a lower FIM efficiency. Although not statistically significant, individuals presenting to our unit with low testosterone levels, on average, stayed 26 days longer than did those with normal levels. Age and the presence of multi-trauma did not appear to be factors associated with serum testosterone levels. Changes in discharge cognitive FIM scores between the two groups approached statistical significance (p = 0.06). CONCLUSION: This pilot study suggests that testosterone levels may be important in the recovery of patients with traumatic brain injury, treated at an in-patient rehabilitation hospital.