Research

Mixed

Poor sleep quality is modestly but consistently associated with poorer cognitive performance, particularly verbal phonemic fluency, across the entire adult lifespan (18-98 years).

Maintain good sleep hygiene throughout your life, not just as you age. This study shows that poor sleep quality consistently impacts cognitive performance, especially verbal fluency, from young adulthood to old age. Prioritizing sleep is a key strategy for maintaining cognitive health at any age.

GoodSupportsMEDIUM confidence
our findings suggests this task, dependent on multiple executive processes, is particularly affected by poor sleep quality... the negative associations between sleep and cognitive performance are a constant feature across the lifespan, rather than specifically in elderly individuals.
Andrew Gadie et al. · BMJ Open · 2017

Why this rating

Large sample size and use of Bayesian regression to quantify evidence for the null in other domains strengthens the credibility of this modest positive finding.

Source

How are age-related differences in sleep quality associated with health outcomes? An epidemiological investigation in a UK cohort of 2406 adults

Andrew Gadie et al. · BMJ Open · 2017

DOI 10.1136/bmjopen-2016-014920

cross_sectional · n=2406Cited 208×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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