Many people with ASD report problems with sleep, but most ASD sleep research to date has focused on children and adolescents, with only a few studies involving adults with ASD. We also know very little about which aspects of sleep are problematic; is it difficulties with going to sleep (sleep onset latency), staying asleep (total sleep time), frequent waking during the night (wake after sleep onset), or less total sleep. There is also very little research into how daytime functioning is affected in adults with ASD who sleep poorly. One of our students, Emma Baker, has therefore decided to study sleep problems and how they are related to daytime functioning in adults with ASD. Emma is studying for her PhD under the supervision of Associate Professor Amanda Richdale who is one of the international experts on sleep problems associated with ASD.

Emma asked 36 adults with a confirmed, clinical diagnosis of high-functioning ASD to participate in her study and compared their results to those of 36 neuro-typical adults. Both groups were on average 30-35 years old. They completed several questionnaires to measure sleep quality and patterns and daytime functioning, such as feeling refreshed after waking (refreshment), feeling like going to sleep during the day (sleep propensity), and feeling tired (fatigue). They also kept a sleep/wake diary for two weeks to record when they went to bed, sleep onset latencies, total sleep time and how many times they woke after sleep onset. These subjective recording were verified by an ‘actigraph monitor’, which is a watch-like apparatus that is worn overnight.

Emma found that, while there were problematic sleepers in both groups, adults with ASD were more likely to exhibit poorer sleep quality. Compared to neurotypical adults, they took longer to fall asleep, did not sleep as long and woke more frequently during the night. They also did not feel as refreshed upon waking and reported to be more sleepy and fatigued. Interestingly, several adults with ASD reported anxiety/stress disrupted their sleep, which confirms previous findings that certain mental health issues, such as anxiety and/or depression appear to play an important role in the manifestation of sleep problems. Some of the neurotypical control adults also reported anxiety and stress as a problem associated with poor sleep. In addition, three HFASD adults reported that noises disturbed their sleep, which was not reported by any neurotypical adult. Noise sensitivity may be a reflection of sensory issues common to ASD and now part of the diagnostic criteria.

Thus poor sleep persists into adulthood in individuals with ASD and impacts negatively on their daytime functioning. Future research should investigate the causes of these sleep disturbances and how they can be prevented from occurring across the life-span. Additionally, the relationship between sleep problems and other health issues should be investigated. This knowledge will allow the development of tailored interventions and supports.