Multimorbidity, cognitive function, and physical activity.

Area of Science:

• Gerontology
• Cognitive Neuroscience
• Public Health

Background:

• Both physical activity and multimorbidity are known to impact cognitive function in older adults.
• The moderating role of physical activity on the multimorbidity-cognition relationship remains under-explored.

Purpose of the Study:

• To investigate whether physical activity moderates the association between multimorbidity and cognitive function in older adults.
• To evaluate the impact of meeting recommended physical activity levels on cognitive function in the presence of multimorbidity.

Main Methods:

• Utilized data from the 1999-2002 National Health and Nutrition Examination Survey (NHANES).
• Included 2157 participants aged 60 years and older.
• Created a multimorbidity index from physician diagnoses and assessed physical activity via self-report; cognitive function was measured using the Digit Symbol Substitution Test.

Main Results:

• Multimorbidity showed an inverse association with cognitive function in unadjusted and adjusted models.
• This association was largely attenuated for older adults meeting the minimum recommended physical activity level (≥2000 MET-min-month).
• Evidence suggests physical activity moderates the relationship between multimorbidity and cognitive function in this cohort.

Conclusions:

• Physical activity may play a crucial role in preserving cognitive function among older adults with multiple chronic conditions.
• Achieving recommended physical activity levels could be a key strategy to counteract cognitive decline associated with multimorbidity.
• Findings highlight the potential public health benefit of promoting physical activity in aging populations with complex health needs.