New research into the effects of age on sleep suggests the elderly sleep less, but report better quality sleep, and feel more awake during the day.

“Although sleep is a biomarker for general health and pathological conditions, its changes across age and gender are poorly understood,” says researchers from the University of Lausanne, Switzerland, who have responded to this gap in sleep research in a recent paper published in Annals of Medicine: “Age and gender variations of sleep in subjects without sleep disorders.

To assess individuals’ sleep patterns Gianina Luca et al carried out a mixture of subjective and objective evaluation of sleep, ranging from questionnaires to sleep studies. This enabled them to examine both the physical differences in sleep and whether individuals of different ages interpreted their sleep quality differently. The research team studied 6,733 participants, aged 35-75 years, all of whom were “randomly selected between 2003 and 2006 from the adult general population of Lausanne.” They were also keen to exclude individuals who had declared sleep disorders, in order to focus their study on the sleep changes of healthy individuals over the years.

The study  revealed, “Aging was associated with a gradual shift towards morningness,” with the older population going to bed earlier and rising earlier than their younger counterparts. It was also observed that they slept for less time. Despite this reduced sleep-time, the paper says, “Older subjects complain less about sleepiness, and pathological sleepiness is significantly lower than younger subjects,” suggesting that they actually require less sleep.

Sleep latency, the length of time it takes you to fall asleep at night, is shown to increase with age, but only for women, with little difference in men’s speed of getting to sleep. However, “sleep efficiency decreases with age in both genders,” with older people more restless during sleep and more likely to wake up than younger individuals. Although they experienced decreased sleep efficiency, the older participants themselves reported better sleep quality and daytime functioning. Luca et al suggest: “One possible explanation for better rating of daytime and sleep quality is an adaptation of expectations about sleep in older populations, or an acclimatization to sleep changes over time.”

The authors conclude: “Sleep complaints in older subjects are not normal and should prompt the identification of underlying causes.”