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Frailty Assessment in an Aging Mouse Model
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A quantile frailty index without dichotomization.

Garrett Stubbings1, Kenneth Rockwood2, Arnold Mitnitski2

  • 1Department of Physics and Atmospheric Science, Dalhousie University, Halifax, Nova Scotia, Canada B3H 4R2.

Mechanisms of Ageing and Development
|September 13, 2021
PubMed
Summary
This summary is machine-generated.

A new quantile frailty index (QFI) offers a better way to measure health and aging. This improved frailty index (FI) is interpretable and predicts adverse outcomes more effectively than previous methods.

Keywords:
AgingDichotomizationFrailty index (FI)QuantileSummary measures of health

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Area of Science:

  • Gerontology
  • Biostatistics
  • Public Health

Background:

  • Quantifying individual aging processes is crucial for health assessment.
  • Existing frailty index (FI) measures require improvement in interpretability and predictive accuracy for adverse outcomes.

Purpose of the Study:

  • To introduce and validate a novel quantile frailty index (QFI) for health and aging assessment.
  • To compare the performance of QFI against traditional FI measures using diverse datasets.

Main Methods:

  • Developed a QFI by rank-ordering individual risk within a population, avoiding dichotomization.
  • Utilized sex-specific and age-matched reference populations to refine QFI construction.
  • Evaluated QFI performance on cross-sectional laboratory data from NHANES, CSHA, and ELSA.

Main Results:

  • The QFI demonstrated superior performance compared to previous FI measures across multiple datasets.
  • Sex-specific reference populations reduced age-related male-female FI disparities and enhanced predictive power.
  • Controlling for age, either through age-matched populations or as an auxiliary variable, significantly improved predictive performance.

Conclusions:

  • The QFI is a convenient, interpretable, and robust measure of health and aging.
  • Age must be controlled when assessing the predictive performance of health summary measures.
  • The QFI provides a straightforward method for age-controlled health assessment.