AI Insight
This study of 946 older Canadian adults found that higher risk of obstructive sleep apnea (OSA), as measured by the STOP-BANG questionnaire, was significantly associated with self-reported memory problems and slower cognitive processing speed. Insomnia alone or combined with OSA showed no association with these cognitive outcomes. The cross-sectional design prevents determination of causality, but OSA risk and diabetes were the strongest predictors of memory problems, correctly classifying 66.6% of cases.
Why it matters
These findings suggest that screening for OSA in older adults presenting with memory complaints could help identify individuals at higher risk for cognitive impairment. The results indicate that the physiological burden of OSA may be more relevant to cognitive function than sleep fragmentation from insomnia, potentially guiding clinical priorities in sleep disorder management for cognitive health.
Understand the Science
BackgroundObstructive sleep apnea (OSA) and insomnia are highly prevalent in older adults and both have been linked to cognitive decline. However, it remains unclear whether the physiological burden of OSA or the sleep fragmentation associated with insomnia more strongly predicts cognitive impairment. This study examined whether OSA risk or insomnia better was associated with memory problems and cognitive slowing among community-dwelling older Canadians. Given the cross-sectional design, the study evaluated associations rather than causal relationships.MethodsData were drawn from 946 participants in the Canadian Longitudinal Study on Aging (CLSA), including 473 individuals reporting a physician-diagnosed memory problem and 473 age- and sex-matched controls. OSA risk was assessed using the validated STOP-BA(N)G questionnaire. At the same time, insomnia was defined using operational research criteria based on sleep onset latency, wake after sleep onset, and duration. Cognitive processing speed was measured via Choice Reaction Time (CRT). General linear models, logistic regression, and discriminant analyses examined associations between sleep parameters and cognitive outcomes, controlling for age, sex, body mass index, income, and diabetes.ResultsParticipants with memory problems had significantly higher STOP-BA(N)G scores (F(1,931) = 7.10, p = 0.008) and slower CRTs (p = 0.05) compared to controls. Insomnia alone or comorbid with OSA (COMISA) was not associated with cognitive outcomes. In discriminant analysis, STOP-BA(N)G score (r = 0.45) and diabetes (r = 0.26) were the strongest predictors of memory problems, correctly classifying 66.6% of cases. Sex-stratified analyses demonstrated that the association between higher STOP-BA(N)G scores and memory problems remained significant in both men and women, although effect sizes were somewhat larger in men.ConclusionHigher OSA risk was associated with poorer memory and slower cognitive processing in older adults, whereas insomnia was not associated with these outcomes. Because of the cross-sectional design, causality cannot be inferred. Screening for OSA and metabolic comorbidities in patients with memory complaints may help identify individuals at increased risk of cognitive impairment.