In a study of over 7,000 chronic limb-threatening ischaemia (CLTI) patients, researchers found that Black and Hispanic patients had higher three-year amputation and reintervention rates; survival, however, was higher among Black patients and similar between Hispanic and White patients. Aderike Anjorin (Duke University Medical Center, Durham, USA) delivered these findings at this year’s Society for Vascular Surgery (SVS) Vascular Annual Meeting (VAM 2022; 15–18 June, Boston, USA).
Framing the research, Anjorin stated that Black and Hispanic patients have higher rates of CLTI and suffer worse outcomes after lower extremity bypass compared with White patients. The underlying reasons for these disparities are unclear, she said, specifying that data on long-term outcomes are limited. In order to address this gap in the literature, Anjorin and colleagues examined differences in three-year outcomes after open infrainguinal revascularisation for CLTI by race/ethnicity and explored potential factors contributing to these differences.
The research team identified all CLTI patients undergoing primary open infrainguinal revascularisation in the Vascular Quality Initiative (VQI) registry from 2003–2017 with linkage to Medicare through 2018 for long-term outcomes, the presenter detailed. She communicated that primary outcomes were three-year amputation, reintervention, and survival, and that secondary outcomes were factors associated with disparate outcomes.
Anjorin informed the VAM audience that a total of 7,108 CLTI patients were included in the study. Of these patients, she specified, 5,599 (79%) were non-Hispanic White, 1,053 (15%) were Black, 48 (1%) were Asian, and 408 (6%) were Hispanic.
Presenting the study findings, Anjorin reported that Black patients had higher rates of three-year amputation (32% vs. 19%; hazard ratio [HR]: 1.9 [95% confidence interval: 1.7–2.2]), reintervention (61% vs. 57%; HR: 1.2 [1.1–1.3]), and survival (62% vs. 58%; HR: 1.1 [1.01–1.2]) compared with White patients. Hispanic patients, the speaker added, experienced higher rates of amputation (27% vs. 19%; HR: 1.6 [1.3–2]) and reintervention (70% vs. 57%; HR 1.4 [1.2–1.6]) compared with White patients; however, survival was similar between the groups (62% vs. 58%; HR: 1.1 [0.98–1.3]).
In addition, Anjorin relayed that the low number of Asian patients prevented meaningful assessment of amputation (20% vs. 19%; HR: 0.9 [0.4–2]), reintervention (55% vs. 57%; HR: 0.8 [0.5–1.2]), or survival (64% vs. 58%; HR: 1.2 [0.8–1.9]) in this group.
In adjusted analyses, the speaker communicated, the association of Black and Hispanic race with amputation and reintervention was explained primarily by differences in demographic characteristics (age, sex) and baseline comorbidities (tobacco use, diabetes, renal disease).
Anjorin concluded that disparities in amputation and reintervention rates are partly attributable to demographic characteristics and the higher prevalence of comorbidities in Black and Hispanic patients with CLTI. “Interventions to improve early diagnosis, risk factor modification, and postoperative surveillance in these populations may confer long-term limb salvage benefits,” the speaker told VAM attendees.
“Is ethnicity simply a marker for socioeconomic status, and is that driving these outcomes?” was the first question in the discussion following Anjorin’s presentation. “It is very likely that socioeconomic status plays a role,” the speaker responded. However, she stressed that the data used in the team’s study make it hard to establish exactly how big a role it plays, in part because all patients that have been included are insured, and therefore likely do not represent the entire CLTI population.
Expanding on this point in response to another question, Anjorin remarked that there are other factors at play in the differing outcomes. She emphasized the importance of considering social determinants of health, such as health literacy and geographic location affecting access to centres for exercise therapy, for example. “Unfortunately, we do not have these variables in the current dataset,” she said.
SVS president and session moderator Ali AbuRahma (West Virginia University, Charleston, USA) was keen to get Adjorin’s take on whether CLTI patients were visiting a physician too late and therefore presenting with too advanced disease for treatment. The speaker replied: “We did look at urgency status, and in our adjusted analysis this did not really play a huge role for amputation or reintervention, so it really was the higher burden of comorbidities that drove these differences.”
In another question from the audience, a delegate asked whether the presenter could comment on racial disparities as they pertain to the decision to undergo primary amputation, i.e. those who have an upfront decision to undergo primary amputation as opposed to revascularization and then amputation. Given that the research team used VQI data, Anjorin responded that they do not have the data on individual patient decision-making.
Honing in on the specifics of the study, one delegate asked whether the study group looked at target artery for their analysis. The team looked at distal bypass, Anjorin communicated, noting that they focused on bypass into an infrapopliteal target specifically. “For Black patients, the association with amputation was slightly attenuated, I think by 0.1, and for Hispanic patients, when we looked at distal bypass reinterventions specifically, the association for Hispanic patients and reintervention was attenuated.”
Anjorin performed the analysis and delivered the presentation “Racial and ethnic disparities in long-term outcomes following open revascularization for chronic limb-threatening ischemia” under the guidance of senior author Marc L Schermerhorn (Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, USA).