Sex Disparities in Long Term Outcomes After Open Surgery for Chronic Limb Threatening Ischaemia: A Propensity Score Matched Analysis of Health Insurance Claims

OBJECTIVE: Several studies suggest a disadvantage for women in peri-operative morbidity and mortality after open surgery in peripheral arterial occlusive disease. In addition to their heterogeneity regarding design and analysed cohorts, long term data are mostly missing. This study aimed to determine sex disparities in outcomes after open revascularisation in chronic limb threatening ischaemia (CLTI).

METHODS: Using health insurance claims data of the second largest insurance fund in Germany, BARMER, a large cohort of patients was sampled consecutively for analysis including index open surgical revascularisations of CLTI performed between 1 January 2010, and 31 December 2018. Propensity score matching was used to adjust for confounding. Sex related differences regarding overall survival, amputation free survival (AFS), and cardiovascular event free survival (CVEFS) during the five years after surgery were determined using Kaplan-Meier time to event curves, log rank test, logistic, and Cox regression.

RESULTS: Among 9 526 patients (49.5% women) in the entire cohort, 6 502 patients were matched. Before matching, women were older at presentation (78.0 vs. 71.8 years, p < .001) and suffered more often from multiple comorbidities (van Walraven score > 9, 55.5% vs. 50.6%, p < .001). During the hospital stay, there were 692 (7.3%) deaths, while 4 631 deaths (48.6%) occurred during the follow up. In the matched cohort, the median follow up was 746 days for women and 871 days for men. In the matched analyses, female sex was significantly associated with better overall survival (hazard ratio, HR, 0.80, log rank p < .001), AFS (HR 0.81, log rank p < .0001), and CVEFS (HR 0.84, log rank p < .001) five years after the index treatment.

CONCLUSION: In this largest propensity score matched analysis of health insurance claims to date from Germany, evidence was found for better long term outcomes in women after open surgical revascularisations for chronic limb threatening ischaemia. Future guidelines and studies should address the impact of sex on patient selection practice and outcomes to determine the underlying reasons for existing disparities.