A recent study has revealed a surprising early warning sign of dementia: large jumps in daytime sleepiness, including frequent or heavy napping. Researchers believe this change in sleep behaviour may come well before more familiar symptoms like memory loss or confusion.
The study followed 733 women in their 80s using sleep trackers, over a period of five years. At follow-up, 164 of these women had developed mild cognitive impairment, and 93 were diagnosed with dementia. The scientists found that those who began to sleep more in the day, especially those who experienced big increases in sleepiness or who napped often, were more likely to show cognitive decline.
While doctors already watch for warning signs such as getting lost, trouble speaking, or repeating questions, this new finding suggests that changes in sleep patterns could act as an early marker. In particular, consistent or excessive napping during the day might be one of the first visible clues.
Dr. Clifford Segil, a neurologist involved in commenting on the research, noted the importance of sleep in memory consolidation and the process by which short-term memories become long-term memories. He suggested that good nighttime sleep may be more vital for people in their eighties than daytime naps.
The researchers caution that not all sleep changes lead to dementia, and scientists do not yet fully understand why sleep and cognitive decline are linked in this way. However, they argue this new symptom might help with earlier detection of dementia in older women, potentially allowing for interventions sooner.
Health experts recommend that anyone noticing a marked increase in daytime sleepiness especially in older age should consult a healthcare provider. Early evaluation may include tracking sleep habits, assessing memory, and ruling out other conditions that could cause fatigue or napping.
