Operationalizing a frailty index using routine blood and urine tests

Area of Science:

• Geriatric Medicine
• Clinical Biochemistry
• Biomarkers

Background:

• Developing uncomplicated frailty instruments is crucial for busy clinical settings.
• Frailty assessment is essential for managing older adults.

Purpose of the Study:

• To operationalize a frailty index (FI-Lab) using routine blood and urine tests.
• To evaluate the properties and predictive accuracy of the FI-Lab compared to other frailty instruments.

Main Methods:

• Secondary analysis of a prospective cohort study involving 306 patients aged ≥65 years.
• Operationalized FI-Lab (22 blood parameters, 1 urine parameter) and other frailty measures (FI-CGA, FI-combined, CFS, etc.).
• Follow-up data collected up to 1 year post-discharge.

Main Results:

• FI-Lab correlated significantly with all other frailty instruments (P<0.001).
• FI-Lab demonstrated good predictive accuracy for 6-month and 1-year mortality (AUCs ~0.76-0.77).
• Each 0.01 increment in FI-Lab increased mortality risk by 7.2% (6-month) and 7.1% (1-year), adjusted for age and sex.

Conclusions:

• The FI-Lab exhibits key characteristics of a valid frailty index.
• FI-Lab can be utilized as a standalone frailty measure.
• FI-Lab is suitable for combined use with other frailty assessment tools.