Variation in treatment and outcomes for patients with chronic limb-threatening ischaemia in New South Wales, Australia

Background Chronic limb-threatening ischaemia (CLTI) carries significant amputation and mortality risks. Australian population-based outcomes for CLTI are inadequately known. This study aimed to distinguish factors associated with outcomes in the first 2 years after CLTI surgery. Methods By linking routinely collected health administrative and mortality data from New South Wales, this population-based cohort study identified patients with ischaemic rest pain, gangrene or ulceration undergoing vascular surgery in public hospitals between 2010 and 2012. The primary outcome was 2-year amputation-free survival (AFS), and secondary outcomes included readmission and reoperation rates. Multivariable regression analysis identified prognostic factors adjusted for patient, hospital and geographic factors. Results Primary CLTI surgery was performed on 4898 patients. Almost half the cohort had minor amputations without concurrent revascularization (2398, 49%), and the remaining patients had open (652, 13%) or endovascular (1848, 38%) surgery. At 2-years, the AFS rate was 72%. Significant disparity was seen between age groups, with the 2-year AFS 71% in patients aged 75 years or older, compared to 95% in patients aged less than 75 years (P < 0.001). Place of residence or hospital training status did not significantly influence AFS or readmission, but non-training hospitals had higher rates of reoperation. Conclusion This population-based cohort study demonstrated variable outcomes for patients with CLTI, particularly with respect to older age, admission acuity and comorbidity. Results may guide service improvements however further research is needed into how population-wide health initiatives can address age-related disparities in CLTI.