Cardiorespiratory Fitness Prediction Models For Vestibular Hypofunction. Does One Size Fit All?

Cardiorespiratory fitness (CRF) is an independent predictor of mortality risk. The gold standard for CRF assessment is peak oxygen uptake (V̇O2peak). Low-cost prediction equations are available for the estimation of V̇O2peak. Nevertheless, V̇O2peak population-specific prediction models for people with vestibular hypofunction (VH) have not been developed yet. PURPOSE: To 1) develop two V̇O2peak prediction models, with (VHG) and without (VHN-G) expired gas analysis, for people with VH; 2) cross-validate the developed predictions models; and 3) compare the precision of these models with the ones available in the literature. METHODS: A progressive ramp protocol (40 W + 10 W/min) to symptom-limited maximum on a cycle ergometer was used for gas exchange threshold (GET), peak power output (Wpeak) and V̇O2peak determination. Descriptive patients’ data (n = 54, 58 ± 10 yr old) and exercise test characteristics were used to develop VH-specific V̇O2peak prediction models. A 100-fold repeated cross-validation was performed using the newly developed equations. Three V̇O2peak prediction equations (ACSM, ACSM Corrected, and FRIEND formulas) available in the literature were applied to VH participants. RESULTS: The developed prediction models were extremely accurate in predicting V̇O2peak (Figure 1). Repeated cross-validation analysis showed a mean bias of 0.1 ± 3.0 and 0.6 ± 3.5 mL·min-1·kg-1 for VHG and VHN-G, respectively. ACSM equation significantly (P < 0.001; mean bias: -2.4 ± 3.3 mL·min-1·kg-1) overestimated V̇O2peak, while ACSM Corrected (mean bias: 1.7 ± 3.0 mL·min-1·kg-1) and FRIEND (mean bias: 1.4 ± 3.5 mL·min-1·kg-1) equations significantly (P < 0.001) underestimated V̇O2peak. CONCLUSIONS: VH-specific prediction models offer lower estimation errors compared to prediction models available in the literature. These findings facilitate the evaluation of CRF and the ongoing adjustments of exercise-based treatment programs in people with VH. Supported by: Vital Fundazioa (VITAL21/14). Vital Fundazioa-Bioaraba (BAFV22-012). PREDOCTORAL GRANT (PIF21/160)