Many patients experience sleep problems in ICU and up to a week after leaving but the researchers said there was previously little research onlong-term effects.
The team studied 497 patients aged 17–74 who were admitted for more than 24 hours to ICUs at three hospitals.
At six and 12 months after discharge, patients were surveyed on sleep disturbances and quality of life. A random sample of 10,000 other patients was used as a reference group.
Nearly 40% of ICU patients experienced disturbed sleep for up to a year after discharge. ICU patients had more difficulty falling asleep, poorer quality of sleep and slept for shorter periods than controls.
But, at both six and 12 months, the main factor that affected sleep in those in the ICU group was underlying illness such as asthma, diabetes and psychiatric conditions, the authors said. ‘Concurrent disease was found to be most important as an underlying cause,’ they said.
However, Tracy Pilcher, a consultant nurse in critical care at United Lincolnshire Hospitals NHS Trust, said she was not convinced by the findings. She said it was difficult to determine whether it was underlying disease, ICU or a combination of both that contributed to ongoing sleep disturbances.
Whatever the cause, Ms Pilcher said, staff in ICU should focus on what they could do to try and limit sleep disturbances.
Measures to maintain day and night-time cycles of wakefulness and sleep already took place. They could also look at delirium management, she added.
Diane Miller, a lead critical care outreach nurse from South Tyneside District Hospital, was previously a patient in the ICU where she then worked and had nightmares and hallucinations for a long period after being discharged. ‘Before I never anticipated that you could have hallucinations and nightmares, memory problems and flashbacks and that it feels like you are losing your mind,’ she said.