Untreated sleep apnea can affect sleep in many ways. The respiratory disturbances caused by sleep apnea can keep sleep shallow, meaning the deep healing stages of sleep may not be reached. Untreated sleep apnea also typically causes more awakenings. As you may have noticed, there is a relationship between awakenings and dreams. Awakening during REM sometimes brings about awareness of a dream, meaning increased awakenings during REM could cause a feeling of more intense or frequent dreams. What’s more, people often have more severe sleep apnea during REM sleep than during non-REM stages. So for those who experience many nightmares and who also have untreated sleep apnea, can treatment help to alleviate the issue?
Those suffering from post-traumatic stress disorder (PTSD) often report frequently occurring vivid nightmares and that are often very frightening and unpleasant. Using a population of subjects with PTSD, a research team set out investigate whether sleep apnea treatment (CPAP) would reduce the number of nightmares by reducing awakenings. Before the initiation of CPAP, subjects estimated the amount of nightmares they had per week. Subjects were then treated with CPAP for 6 months and were brought back to the clinic for examination. Data of their CPAP usage and information about their apnea severity were extracted from the recording chip inside the CPAP machine. Subjects were again questioned about their nightmare frequency at follow-up.
Results showed that CPAP initiation did indeed reduce nightmare frequency. Before treatment, subjects reported about 10 nightmares per week and after treatment they reported about 5. Additionally, the amount of CPAP usage predicted the reduction of nightmares. In other words, for every 10% increase in CPAP usage, there was a decrease of 1 nightmare per week. Importantly, sleepiness was also reduced in those who were effectively using their CPAP devices1.
Although many think that dreams (and therefore nightmares) are a natural part of sleep, sometimes we only become aware of them when sleep is disturbed. Because of this, improving sleep quality does seem to decrease the frequency of nightmares in a population with PTSD. Overall, this study is not only relevant to those with PTSD, but also to others as it clearly illustrates the improvement in sleep quality in general, which has major implications for quality of life.
1. Pre-publication: Journal of Clinical Sleep Medicine: The effect of continuous positive airway pressure (CPAP) therapy on nightmares in patients with post-traumatic stress disorder (PTSD) and obstructive sleep apnea (OSA).