Changes in Housework Frequency and Subsequent Cognitive Function and Rate of Decline Among Adults Aged ≥ 65 in the United States, 2008-2018.

Introduction: Physical activity level plays a role in modifying the likelihood of developing Alzheimer's disease and related dementias. However, little is known about how changes in housework affect cognitive function among US adults over the age of 65. This study investigates the correlation between changes in housework frequency and cognitive function over 10 years.

Methods: Data from 8141 adults aged ≥ 65 years in the Health and Retirement Study were analyzed, with changes in housework frequency categorized as "consistently high," "low to high," "high to low," and "consistently low" from 2008 to 2010. Cognitive function was measured from 2010 to 2018 using a composite score (range = 0-35), and mixed-effects linear regression models were fitted.

Results: Of 8141 participants (median age: 75 years [SD: 6.6] and 59.3% female), individuals who reported changes in housework frequency from high to low and consistently low were associated with an additional cognitive decline of 0.079 (95% CI, -0.117 to -0.042) and 0.090 (95% CI, -0.126 to -0.054), respectively, relative to those whose housework frequency remained consistently high. There was no statistically significant additional decline among adults reporting low to high frequency compared with those reporting consistently high housework frequency (β = -0.027; 95% CI, -0.074 to 0.019; P = .252). This association was similar among women and men (P_interaction = .765) and was also similar among adults aged ≥ 80 years and those aged 65-79 years (P_interaction = .069).

Conclusion: Transitioning from low to high or maintaining consistently high housework engagement in later life was associated with a delay in cognitive decline, regardless of gender and age.