Sex-specific differences between C-reactive protein and appendicular lean soft tissue index in heart failure: findings from the National Health and Nutrition Examination Survey.

Higher CRP was not associated with ALSTI in unadjusted models but showed a significant negative association in fully adjusted models in HF patients.

• Study analyzed 73 HF patients (36 males, 37 females) aged ≥18 years from NHANES
• Higher CRP defined as the top 50th percentile of the cohort
• Unadjusted model: p = 0.39 (non-significant)
• Fully adjusted model: b = -0.41 kg/m2, 95% CI -0.79 to -0.02, p = 0.04
• ALSTI was calculated using lean soft tissue adjusted for height squared (kg/m2) and CRP was measured via latex-enhanced nephelometry

Sex-stratified analyses revealed a significant negative association between higher CRP and ALSTI in males with HF, but not in females.

• Males: b = -0.69 kg/m2, 95% CI -1.23 to -0.16, p = 0.01
• Females: p = 0.47 (non-significant)
• Sample included 36 males and 37 females with HF
• Linear regression models were employed to assess the association between CRP and ALSTI

In patients aged ≥50 years, the negative association between higher CRP and ALSTI remained significant in males but not in females.

• Males ≥50 years: b = -0.70 kg/m2, 95% CI -1.33 to -0.08, p = 0.03
• Females ≥50 years: b = 0.69 kg/m2, 95% CI -1.59 to 2.96, p = 0.51 (non-significant)
• The direction of the association was opposite between sexes in this age group

Elevated CRP demonstrated significantly negative female-male differences in associations with ALSTI for both 18–59- and 50–59-year-olds.

• Significant sex interaction for both the 18–59 and 50–59 age groups (p < 0.01)
• These findings indicate that the relationship between CRP and ALSTI differs significantly by sex in these age ranges
• The pattern suggests males bear a disproportionately greater burden of inflammation-related muscle loss in HF

Heart failure in this study population was accompanied by muscle wasting assessed via appendicular lean soft tissue index and elevated CRP as a marker of inflammation.

• ALSTI used as a measure of appendicular muscle mass, calculated as lean soft tissue (kg) divided by height squared (m2)
• CRP measured via latex-enhanced nephelometry
• The study focused on potential sex differences in the CRP–ALSTI relationship within HF patients from the NHANES database
• Total sample size was 73 HF patients aged ≥18 years