Biomarkers Associated with Physical Resilience After Hip Fracture.

Area of Science:

• Gerontology
• Molecular Biology
• Biomarker Discovery

Background:

• Older adults exhibit heterogeneous responses to health stressors, linked to physical resilience.
• Molecular underpinnings of physical resilience remain largely unknown.
• Physical resilience after hip fracture can be measured by the expected recovery differential (ERD).

Purpose of the Study:

• To identify molecular biomarkers associated with physical resilience after hip fracture.
• To investigate the relationship between specific biomarkers and the expected recovery differential (ERD).

Main Methods:

• Quantified biomarkers of inflammation, metabolic/mitochondrial function, and epigenetic dysregulation in serum from the Baltimore Hip Studies (N=304).
• Employed principal component analysis, canonical correlation, and LASSO regression to identify biomarker associations with ERD.
• Assessed biomarkers including TNFR-I, TNFR-II, sVCAM-1, IL-6, metabolic factors, and circulating microRNAs.

Main Results:

• A comprehensive biomarker set explained 37% of the variance in ERD (p < .001).
• LASSO regression identified a subset of biomarkers accounting for 27% of ERD variance.
• Key predictors included a metabolic factor (aspartate/asparagine, C22, C5:1, lactate, glutamate/mine), TNFR-I, miR-376a-3p, and miR-16-5p.

Conclusions:

• Identified a specific set of biomarkers predicting 27% of the variance in physical resilience (ERD) after hip fracture.
• These ERD-associated biomarkers may aid in predicting physical resilience in older adults facing acute health stressors like hip fracture.