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

Cardiorespiratory fitness (CRF) is a strong predictor of health and mortality. However, its gold-standard assessment, peak oxygen uptake (V̇O2peak) via cardiopulmonary exercise testing (CPX), is not always feasible in clinical practice. This study aimed to 1) develop exercise-based CRF prediction models for people with vestibular hypofunction (VH) and 2) evaluate the applicability of existing models to this population. Fifty-four adults with unilateral or bilateral VH (56% women) completed maximal CPX for V̇O2peak determination. CRF prediction models were developed using maximal (VHmax) and submaximal (with [VHsub G] and without [VHsub N-G] gas exchange analysis) test characteristics. A 100-fold repeated cross-validation assessed model accuracy. VHmax (r = 0.90, SEE = 3.0), VHsub G (r = 0.86, SEE = 3.6), and VHsub N-G (r = 0.79, SEE = 4.3) showed high predictive accuracy, with minimal bias (<1%). Existing equations misestimated CRF (ES = 0.56–0.68, large). Predictions within ±1 MET were higher for VH models, reaching up to 8–9 out of 10 individual cases. The newly developed VH-specific models offer more accurate, clinically applicable tools for CRF estimation across various clinical scenarios, including settings where maximal testing is not feasible. An automated calculator was developed to support clinical implementation in VH management.