Poor sleep quality linked to worse physical, mental health outcomes in older adults

Key takeaways:

• Individuals who did not have good sleep had a higher risk of incident motoric cognitive risk syndrome.
• Those who reported excessive sleepiness and lower enthusiasm had a significant risk of MCR.

In a cohort of community-dwelling older adults, poor sleep quality was indicative of incident motoric cognitive risk syndrome as well as increased physical and mental disability, according to research published in Neurology.

“Sleep disturbances and cognitive impairment frequently coexist in aging and the association between the two may be bidirectional,” Victoire Leroy, MD, PhD, of the department of neurology at Albert Einstein College of Medicine, and colleagues wrote. “Poor sleep quality has been shown to be associated with higher risk of dementia.”

Sleep disturbances are linked with cognitive impairment risk, but research has not yet verified the associations between sleep and motoric cognitive risk syndrome (MCR), which includes slow gait speed and cognitive complaints, Leroy and colleagues wrote.

They sought to examine the association of sleep disturbances with both incidence and prevalence of MCR in those aged 65 years and older and living in a community of similarly aged individuals.

Their study recruited 445 adults (mean age, 75.9 years; 57% women) without dementia from the Central Control of Mobility and Aging cohort, for inclusion in the study conducted at Albert Einstein College of Medicine.

MCR was defined as self-reported cognitive issues on standardized questionnaires, while gait speed was recorded on an electronic treadmill and examined both at baseline and annual follow-up visits.

Participants were subdivided into “good” sleepers (5) and “poor” sleepers (>5) based on an established cut score from the 18-item Pittsburgh Sleep Quality Index (PSQI), which encompasses seven individual components of sleep quality.

Symptoms of depression and anxiety were assessed via the 30-item Geriatric Depression Scale and the Beck Anxiety Inventory, with additional metrics applied to social and health concerns in this population.

Data analysis included hazard models adjusted for age, sex and education collectively and for comorbidity index, Geriatric Depression Scale score and global cognitive score, as well as to examine associations between poor sleep quality and prevalent MCR at baseline in the overall study population.

According to results, 36 out of 403 MCR-free participants at baseline developed MCR across a mean follow-up of 2.9 years.

Data showed that poor sleepers recorded a higher risk of incident MCR (HR = 2.7; 1.2-5.2) compared with those who were good sleepers; however, this association was not significant when adjusting for depressive symptoms (aHR = 1.6; 0.7–3.4).

Leroy and colleagues also reported that, among PSQI components, only those who reported excessive sleepiness and lower enthusiasm had a significant risk of MCR in fully adjusted models (aHR = 3.3; 1.5–7.4). Poor sleepers tended to be significantly older than good sleepers, were more frequently disabled and demonstrated more depressive symptoms than better-sleeping counterparts.

Conversely, prevalent MCR was not associated with poor sleep quality.

“Our findings emphasize the need for an early screening of sleep disturbances as a potential preventive intervention for cognitive decline, whether depressive symptoms are present,” Leroy and colleagues wrote.