VICTORIA, Australia—Traumatic brain injury (TBI) may adversely affect the body’s ability to produce melatonin, which may account for sleep disturbances commonly seen in TBI patients, according to a new study (Neurology. 2010;74:1732-1738). Researchers from Monash University, Victoria, investigated sleep-wake disturbances and their underlying mechanisms in a cohort of 23 patients with TBI and 23 age- and gender-matched volunteers.
TBI patients reported higher anxiety and depressive symptoms and sleep disturbance than control subjects. The TBI patients also had decreased sleep efficiency and increased wake after sleep onset, although there were no differences in self-reported sleep timing. Patients with TBI had significantly lower levels of evening melatonin production, and levels of melatonin were significantly correlated with REM sleep. The researchers concluded the reduced melatonin production suggests a disruption in circadian regulation of melatonin synthesis.
Bill Hendrick reported on the study for WebMD, and interviewed one of the researchers, Shantha Rajaratnam, Ph.D., who noted researchers were aware that people with brain injuries often have sleep problems, but the etiology has been unknown. He said, “These results suggest that the brain injury may disrupt the brain structures that regulate sleep, including production of melatonin.” Rajaratnam added the study results suggest future trials could explore whether taking melatonin supplements could improve sleep in people with brain injuries.
