Skeletal Muscle Function Deficit Longitudinal Associations With Inflammation and Caloric Intake in Elderly. The...

Area of Science:

• Gerontology
• Muscle Physiology
• Nutritional Science

Background:

• The Skeletal Muscle Function Deficit (SMFD) score is a composite measure of muscle health, integrating mass, strength, power, and quality.
• Aging is associated with a decline in muscle function, impacting overall health and independence in older adults.

Purpose of the Study:

• To investigate the longitudinal associations between systemic inflammation (Interleukin-6, IL-6) and caloric intake with SMFD-score trajectories in older adults.
• To determine how inflammation and caloric intake influence the decline of muscle function over time.

Main Methods:

• Utilized data from the InCHIANTI longitudinal cohort study, including 1035 community-dwelling older adults.
• Assessed SMFD-score, IL-6 levels, and caloric intake across four study waves using linear mixed-effects models.
• Adjusted for baseline age, sex, multimorbidity, and body mass index in longitudinal analyses.

Main Results:

• SMFD-score significantly declined over follow-up, while IL-6 levels increased.
• Higher IL-6 levels were associated with accelerated SMFD-score decline.
• Higher caloric intake was linked to a higher SMFD-score and slower functional decline, partially attenuating the negative effects of IL-6.

Conclusions:

• The SMFD-score effectively captures longitudinal muscle function decline in aging.
• Systemic inflammation and caloric intake exert opposing influences on muscle health trajectories.
• Findings highlight the SMFD-score's clinical relevance for identifying modifiable factors in muscle aging and functional decline.