Joint Associations of Physical Activity and Sleep Quality With Cognitive Function Among Older Adults in China

INTRODUCTION: The joint associations of physical activity (PA) and sleep quality with cognitive function remain unclear. METHODS: The study was an observational analysis of an 8-week clustered randomized controlled trial with a 24-month follow-up in rural older Chinese. The trial took place from May 2021 to May 2023, in Sichuan, China. The participants' cognitive function was evaluated using the Telephone Interview for Cognitive Status. Linear mixed effects models and stratified analysis were performed. RESULTS: The study population comprised a total of 498 older adults. The average age was 70.96, and 55.4% were female. The interaction between PA and sleep quality was significant on global cognition ( P =0.04) and memory ( P =0.04). Compared with the low-PA and poor sleep quality group, any category of PA combined with sleep quality had better global cognition function, and the high-PA and good sleep quality group had the best global cognition function ( β =0.58, 95% CI: 0.29-0.92) and memory ( β =0.43, 95% CI: 0.23-0.64). CONCLUSION: Both higher levels of PA and better sleep quality are important for cognitive health, supporting the need for dual-behavior interventions in aging populations.