For older adults' restful sleep, ambient temperature should be 20-25 degrees Celsius: Study

Ambient night-time temperature for older adults to have a restful sleep should be between 20 and 25 degrees Celsius, according to newly published research.

Further, sleep efficiency in the older adults, aged 65 years or above, was found to drop by 5-10 per cent as the ambient night-time bedroom temperature rose to 30 degrees Celsius, the study found, despite substantial differences among the individuals studied.

A lowered sleep quality in the long-term has been linked with cognitive decline and dementia in older adults, along with impacting their mood by making them irritable and less productive in the day.

Sleep quality in older adults could, thus, potentially be enhanced by optimising home thermal environments, the study from Marcus Institute for Aging Research and Harvard Medical School, Boston, US, said about its findings which, it said, emphasised the importance of personalised temperature adjustments based on individual needs and circumstances.

From a climate adaptation point of view, the study findings are important as cities are projected to become warmer due to a combination of both climate change and urban induced warming, it said.

"The study underscores the potential impact of climate change on sleep quality in older adults, particularly those with lower socioeconomic status, and supports increasing their adaptive capacity as nighttime temperatures increase in cities across the country," said Amir Baniassadi, lead researcher of the study published in the journal Science of The Total Environment.

Older adults often experience inadequate, restless, and disrupted sleep, in turn, influencing their health-outcomes with regards to diabetes management and risk of developing cardiovascular diseases.

While numerous medical and behavioural interventions have been developed to improve outcomes related to sleep, the potential of environmental interventions has largely been overlooked, the study said, pointing to the important influence that sleep environment has on the elderly.

The long-term observational study collected sleep and environmental data over 212 nights from each of the 50 community dwelling older adults included for analysis. In total, the study had 10,903 person-nights of data.

The researchers thus monitored sleep duration, efficiency, and restlessness over an extended period within participants' homes.

Further research was needed to identify sleep-related outcomes that would have most impact on short and long- term health and wellbeing of older adults, they said. For example, establishing which outcome related to habitual sleep presents the strongest association with the rate of long-term cognitive decline.

Understanding these links could enable researchers and health care providers to fine tune their environmental interventions based on most important outcomes related to sleep, they said.