Evaluation of determinants of walking fitness in patients attending cardiac rehabilitation

AIM: This study aims to investigate the ability of patients’ baseline characteristics to predict the distance walked during the incremental shuttle walk test (ISWT) in the cardiac rehabilitation (CR) population and to produce reference values to guide practice. METHODS: Secondary analysis was conducted on National Audit Cardiac Rehabilitation data collected between 2010 and 2015. Patients (n=8863) were included if they were aged ≥18 years and had a recorded ISWT score assessed before starting CR. Stepwise regression was used to identify factors predicting the ISWT distance. Age, gender, body mass index, height, weight; presence of hypertension, dyslipidemia or diabetes; smoking and physical activity were independent variables. ISWT distance was the dependent variable. The 25th, 50th and 75th percentiles of the ISWT distance were used as reference values. RESULTS: Age and gender explained 27% of the variance of the distance covered in the ISWT (R(2)=0.27, adjusted R(2)=0.27,Standard Error of the Estimate (SEE) = 148.7, p<0.001). Reference values using age and gender categories were developed. CONCLUSION: Age and gender were the significant factors for predicting the walking fitness in the CR population, with age being the best predictor. The age and gender reference values produced represent a potentially valuable tool to be used in the clinical setting.