Sarcopenic obesity and inflammation in the InCHIANTI study

Area of Science:

• Gerontology
• Obesity Research
• Inflammation Biology

Background:

• Aging is associated with increased fat mass and decreased muscle mass.
• Sarcopenic obesity, an extreme manifestation, involves both muscle loss and excess fat.
• Adipose tissue, particularly visceral fat, releases inflammatory cytokines that may accelerate muscle breakdown.

Purpose of the Study:

• To investigate the association between obesity, muscle strength, and circulating proinflammatory cytokines.
• To test the hypothesis that sarcopenic obesity components correlate with elevated inflammatory markers.

Main Methods:

• Cross-sectional study of 378 men and 493 women aged 65+ in Tuscany, Italy.
• Data collected on anthropometrics, handgrip strength, and inflammatory markers (IL-6, C-reactive protein, IL-1 receptor antagonist, soluble IL-6 receptor).
• Participants classified by sex-specific tertiles of waist circumference and grip strength, and BMI for obesity.

Main Results:

• Components of sarcopenic obesity were associated with elevated levels of IL-6, C-reactive protein, IL-1 receptor antagonist, and soluble IL-6 receptor.
• Adjustments were made for age, sex, education, smoking, physical activity, and comorbid diseases.
• Central obesity showed a stronger association with inflammation than global obesity.

Conclusions:

• Obesity, especially central obesity, directly influences inflammation.
• Inflammation negatively impacts muscle strength, contributing to sarcopenic obesity development and progression.
• Proinflammatory cytokines may play a critical role in the pathogenesis of sarcopenic obesity.