DEMENTIA onset is significantly more likely if a person experiences sleep disturbances during midlife or late life, according to a new study from the Karolinska Institutet, Solna, Sweden. The findings suggest that more targeted interventions for sleep disturbances are required to help combat dementia.
Lifestyle and Dementia
The recently published FINGER trial has shown how lifestyle changes can positively impact cognitive functioning, including diet, exercise, and management of vascular risk factors. Currently, however, there is limited understanding on the effect of sleep on dementia risk.
Link Between Sleep and Dementia
In this new study, the team analysed the relationship between sleep and dementia in over 2,000 men and women from three population-based studies from Finland and Sweden. This assessed multiple sleep parameters and standardised dementia diagnoses and included long follow-up duration. Adjustments were made for factors that could influence the results, such as levels of physical activity, genetics, and sleep medications.
It was found that insomnia was linked with a 24% increased risk of dementia onset later in life among people in midlife (aged in their 40s or 50s). In late life participants (aged in their 60s or 70s), terminal insomnia (waking up too early) was associated with a two-fold greater risk for later development of dementia; in the same cohort, long sleep duration (>9 hours of sleep per night) was associated with a four-fold increased chance of later dementia onset. The team acknowledged that the latter of these findings may be influenced by undiagnosed, pre-existing dementia-related pathology.
Targeting Sleep Disturbances
The study therefore suggests that improving sleep, in addition to other lifestyle factors previously identified as being associated with increased risk of dementia, should be a major focus for combatting the condition. “Our findings have direct clinical implications and combined with previous studies they indicate that different stages in the life course are sensitive to sleep disturbances, which in turn increase the risk for dementia. These sleep disturbances necessitate closer clinical attention and the implementation of tailored interventions,” commented lead author Dr Shireen Sindi, Karolinska Institutet.
The team are now planning to investigate the association between sleep disturbance and cognitive function and dementia further among different populations, such as memory clinic patients. Additionally, they want to study the biological mechanisms that underpin this link.
James Coker, Reporter
For the source and further information about the study, click here.