TY - JOUR
T1 - Validation of the Pittsburgh Performance Fatigability Index in the Study of Muscle, Mobility and Aging
AU - Harezlak, Jaroslaw
AU - Cawthon, Peggy M.
AU - Cummings, Steven R.
AU - Forman, Daniel E.
AU - Goodpaster, Bret H.
AU - Hawkins, Marquis
AU - Moored, Kyle D.
AU - Nicklas, Barbara J.
AU - Toledo, Frederico G.S.
AU - Toto, Pamela E.
AU - Santanasto, Adam J.
AU - Strotmeyer, Elsa S.
AU - Newman, Anne B.
AU - Glynn, Nancy W.
AU - Qiao, Yujia
N1 - Publisher Copyright:
© 2023 Oxford University Press. All rights reserved.
PY - 2023/12/1
Y1 - 2023/12/1
N2 - Background: The Pittsburgh Performance Fatigability Index (PPFI) quantifies the percent decline in cadence using accelerometry during standardized walking tasks. Although PPFI has shown strong correlations with physical performance, the developmental sample was relatively homogenous and small, necessitating further validation. Methods: Participants from the Study of Muscle, Mobility and Aging (N = 805, age = 76.4 ± 5.0 years, 58% women, 85% White) wore an ActiGraph GT9X on the nondominant wrist during usual-paced 400 m walk. Tri-axial accelerations were analyzed to compute PPFI (higher score = greater fatigability). To evaluate construct and discriminant validity, Spearman correlations (rs) between PPFI and gait speed, Short Physical Performance Battery (SPPB), chair stand speed, leg peak power, VO2peak, perceived fatigability, and mood were examined. Sex-specific PPFI cut-points that optimally discriminated gait speed using classification and regression tree were then generated. Their discriminate power in relation to aforementioned physical performance were further evaluated. Results: Median PPFI score was 1.4% (25th–75th percentile range: 0%–21.7%), higher among women than men (p < .001). PPFI score was moderate-to-strongly correlated with gait speed (rs = −0.75), SPPB score (rs = −0.38), chair stand speed (rs = −0.36), leg peak power (rs = −0.34) and VO2peak (rs = −0.40), and less strongly with perceived fatigability (rs = 0.28–0.29), all p < .001. PPFI score was not correlated with mood (|rs| < 0.08). Sex-specific PPFI cut-points (no performance fatigability: PPFI = 0%; mild performance fatigability: 0% < PPFI < 3.5% [women], 0% < PPFI < 5.4% [men]; moderate-to-severe performance fatigability: PPFI ≥ 3.5% [women], PPFI ≥ 5.4% [men]) discriminated physical performance (all p < .001), adjusted for demographics and smoking status. Conclusion: Our work underscores the utility of PPFI as a valid measure to quantify performance fatigability in future longitudinal epidemiologic studies and clinical/pharmaceutical trials.
AB - Background: The Pittsburgh Performance Fatigability Index (PPFI) quantifies the percent decline in cadence using accelerometry during standardized walking tasks. Although PPFI has shown strong correlations with physical performance, the developmental sample was relatively homogenous and small, necessitating further validation. Methods: Participants from the Study of Muscle, Mobility and Aging (N = 805, age = 76.4 ± 5.0 years, 58% women, 85% White) wore an ActiGraph GT9X on the nondominant wrist during usual-paced 400 m walk. Tri-axial accelerations were analyzed to compute PPFI (higher score = greater fatigability). To evaluate construct and discriminant validity, Spearman correlations (rs) between PPFI and gait speed, Short Physical Performance Battery (SPPB), chair stand speed, leg peak power, VO2peak, perceived fatigability, and mood were examined. Sex-specific PPFI cut-points that optimally discriminated gait speed using classification and regression tree were then generated. Their discriminate power in relation to aforementioned physical performance were further evaluated. Results: Median PPFI score was 1.4% (25th–75th percentile range: 0%–21.7%), higher among women than men (p < .001). PPFI score was moderate-to-strongly correlated with gait speed (rs = −0.75), SPPB score (rs = −0.38), chair stand speed (rs = −0.36), leg peak power (rs = −0.34) and VO2peak (rs = −0.40), and less strongly with perceived fatigability (rs = 0.28–0.29), all p < .001. PPFI score was not correlated with mood (|rs| < 0.08). Sex-specific PPFI cut-points (no performance fatigability: PPFI = 0%; mild performance fatigability: 0% < PPFI < 3.5% [women], 0% < PPFI < 5.4% [men]; moderate-to-severe performance fatigability: PPFI ≥ 3.5% [women], PPFI ≥ 5.4% [men]) discriminated physical performance (all p < .001), adjusted for demographics and smoking status. Conclusion: Our work underscores the utility of PPFI as a valid measure to quantify performance fatigability in future longitudinal epidemiologic studies and clinical/pharmaceutical trials.
KW - Accelerometry
KW - Fatigue
KW - Gait speed
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U2 - 10.1093/gerona/glad197
DO - 10.1093/gerona/glad197
M3 - Article
C2 - 37566383
AN - SCOPUS:85174311357
SN - 1079-5006
VL - 78
SP - 2387
EP - 2395
JO - Journals of Gerontology - Series A Biological Sciences and Medical Sciences
JF - Journals of Gerontology - Series A Biological Sciences and Medical Sciences
IS - 12
ER -