Objective
To determine the ability of three performance-based measures [Short
Physical Performance Battery (SPPB), gait speed, and Grip Strength] and a
self-report measure [Vulnerable Elders Survey (VES-13)] to predict
functional decline among older women with breast cancer.
Patients and Methods
Longitudinal data from a study of women ≥ 65 years, with newly
diagnosed stage I–III breast cancer, recruited from ambulatory oncology clinics
between July 2010 and April 2014, was used. The primary outcome was functional decline,
Yes or No, defined as a decrease in ≥ 1-point from baseline
to 12 months, on Activities of Daily Living Scales. Multivariable logistic regression
and Receiver Operator Curve analyses were conducted
Results
Among 123 participants 18 (15%) developed functional decline. The
predictive abilities for measures were: SPPB [Adjusted odds ratio (AOR)
= 1.65 per unit decrease in scores, 95% confidence interval (CI)
=1.33–2.05; area under the receiver operator curve (AUC) = 0.93;
sensitivity=94%, specificity=80%]; gait speed
(AOR = 1.76 per unit increase in usual walking time,
CI=1.29–2.41; AUC=0.93; sensitivity=87%,
specificity=79%); VES-13 (AOR = 1.64 per unit increase in
scores, CI=1.31–2.05; AUC=0.87; sensitivity=83%,
specificity=84%); and grip strength: (AOR = 1.18 per unit
decrease in grip strength, CI=1.06–1.30; AUC=0.80;
sensitivity=67%, specificity=77%).
Conclusion
SPPB, gait speed, grip strength and VES-13 all demonstrated excellent
predictive abilities for functional decline. Larger studies are warranted to confirm the
utility of these measures for identifying older adults with cancer at increased risk for
functional decline, who may then be targeted for studies to explore the effects of
interventions to improve function.