What are the determinants of change in walking fitness in patients with a history of depression following cardiac rehabilitation?

Aims This study aims to investigate the demographic, clinical, and service-level factors determining change in walking fitness in cardiac rehabilitation (CR) patients with a history of depression following the CR programme. Methods and results The National Audit of Cardiac Rehabilitation clinical data were used to identify 1476 patients with a history of depression who had their pre- and post-incremental shuttle walk test (ISWT) recorded between 1 January 2016 and 31 January 2020. A multiple linear regression was conducted to examine the determinants of change in walking fitness (m) following CR. Mean age was 61 (SD 10.45), and mean ISWT distance at baseline and outcome was 352.06 m (SD 169.48) and 463.43 m (SD 197.65), respectively. Multivariate analysis revealed that change in walking distance reduced by 1.6 m for each year increase in age at baseline (P < 0.001). Females and unemployed patients had less improvement in walking fitness (23.1 and 21.5 m, respectively). Having a body mass index (BMI) > 30 was associated with lower improvement (24.2 m, P < 0.001), while physically active patients had 14.6 m higher change. Higher baseline ISWT quintiles were associated with less improvement, and increased waiting time to start CR was associated with reduced change in walking fitness following CR. Conclusion Older age, female gender, unemployment, higher baseline BMI, longer waiting time, and lower physical activity were associated with reduced walking fitness improvement in patients with a history of depression. Targeted intervention and prompt access to CR can optimize outcomes. {Graphical Abstract}