Supervised Exercise Therapy for Intermittent Claudication: A Propensity Score Matched Analysis of Retrospective Data on Long Term Cardiovascular Outcomes

Ravindhran, Bharadhwaj; Lim, Arthur J.M.; Kurian, Thomas; Walshaw, Josephine; Hitchman, Louise H.; Lathan, Ross; Smith, George E.; Carradice, Daniel; Chetter, Ian C.; Pymer, Sean

Abstract

Objective: This study aimed to explore the long term outcomes of patients with intermittent claudication (IC) who completed supervised exercise therapy (SET) vs. those who declined or prematurely discontinued SET, focusing on the incidence of chronic limb threatening ischaemia (CLTI), revascularisation, major adverse limb events (MALE), and major adverse cardiovascular events (MACE). Methods: A retrospective registry analysis of consecutive patients with IC who were referred for SET between March 2015 and August 2016 and followed up for a minimum of five years. Serial univariable analysis and logistic regression were performed to identify the statistically significant clinical variables that were independent predictors of each outcome measure. The resulting statistically significant variables were used to guide 1:1 propensity score matching (PSM) using the nearest neighbour method with a calliper of 0.2. Cox proportional hazards regression was used to estimate the hazard ratio (HR) and 95% confidence interval (CI) for the association between SET and the outcomes of interest. Results: Two hundred and sixty-six patients were referred to SET between March 2015 and August 2016. Of these, 64 patients completed SET and 202 patients did not. After PSM, 49 patients were analysed in each cohort. The Cox proportional hazards analysis revealed a significant association between completion of SET and revascularisation requirement (HR 0.46 95% CI 0.25 – 0.84; p = .011), completion of SET and progression to CLTI (HR 0.091, 95% CI 0.04 – 0.24; p < .001), completion of SET and MACE (HR 0.52; 95% CI 0.28 – 0.99; p = .05) and completion of SET and MALE (HR 0.28, 95% CI 0.13 – 0.65; p = .003). The Harrell's C index for all of these models was greater than 0.75, indicating good predictive accuracy. Conclusion: Completion of SET is associated with better outcomes in patients who completed SET compared with patients who declined or discontinued SET with respect to clinically important cardiovascular outcomes over seven years.

Citation

Ravindhran, B., Lim, A. J., Kurian, T., Walshaw, J., Hitchman, L. H., Lathan, R., Smith, G. E., Carradice, D., Chetter, I. C., & Pymer, S. (in press). Supervised Exercise Therapy for Intermittent Claudication: A Propensity Score Matched Analysis of Retrospective Data on Long Term Cardiovascular Outcomes. European journal of vascular and endovascular surgery : the official journal of the European Society for Vascular Surgery, https://doi.org/10.1016/j.ejvs.2023.11.040

• Journal Article Type: Article
• Acceptance Date: Nov 24, 2023
• Online Publication Date: Nov 30, 2023
• Deposit Date: Dec 15, 2023
• Publicly Available Date: Dec 1, 2024
• Journal: European Journal of Vascular and Endovascular Surgery
• Print ISSN: 1078-5884
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• DOI: https://doi.org/10.1016/j.ejvs.2023.11.040
• Keywords: Cardiology and Cardiovascular Medicine; Surgery
• Public URL: https://hull-repository.worktribe.com/output/4483783
• Publisher URL: https://www.sciencedirect.com/science/article/abs/pii/S107858842300970X