Racial and Rural Disparities Observed in Diabetic Foot Ulcer Care

Meghan B. Brennan, MD

New data suggest rural patients who self-identified as Black had a more than 10% absolute increased risk of major leg amputation or death in an overall cohort of US patients with diabetic foot ulcers (DFU).

The observed proportion of death or major leg amputation for rural patients was 18.3% (2402 of 13,100), while for rural patients identifying as Black, the proportion was 28.0% (347 of 1239).

“Our findings demonstrate that the forces underlying racial and rural disparities interact to worsen the health of multiply marginalized individuals,” wrote study author Meghan B. Brennan, MD, University of Wisconsin. “Thus, an intersectionality lens is critical to investigate and address the disparities faced by rural US individuals identifying as Black, including dismantling structural forces that perpetuate inequities.”

Within the United States, data show individuals identifying as Black undergo amputation at twice the rate of individuals identifying as non-Hispanic white, while those in rural areas have nearly 35% higher odds of major leg amputation compared to their urban counterparts.

Brennan and colleagues noted that although racial, rural, and neighborhood disadvantages are well-established, mirroring ongoing systems of marginalization, there are still unknowns on how these social identities unite to affect DFU outcomes.

The current study included a 100% national sample of adult Medicare beneficiaries during acute hospitalization from January 2013 - December 2014 from the US National Medicare Claims Data Database.

The primary outcome was a composite of major leg amputation or death during the index hospitalization or within 30 days after hospital discharge. They investigated 3 social identity metrics: race, ethnicity, rurality, and neighborhood disadvantage.

The Research Triangle Institute race variable used an algorithm to collect patient’s identifying race, while rurality was assigned using Rural-Urban Commuting Area (RUCA) codes and neighborhood disadvantage was measured using the Area Deprivation Index.

Over the study period, a total of 124,487 Medicare beneficiaries (n = 71,286 men; mean age, 71.5; 13,100 rural residents [10.5%]) were hospitalized with DFU). Data show 21,649 individuals (17.4%) identified as Black, 10,158 (8.2%) identified as Hispanic, 88,525 (71.1%) identified as White, and 4155 (3.3%) identified as another race or ethnicity.

Overall, a total of 13,451 patients (10.8%) died and 9617 patients (7.7%) underwent a major leg amputation during index hospitalization or within 30 days of hospital discharge. Data show a nearly 2-fold difference among those presenting with gangrenous ulcers between those identifying as Black and those identifying as White (4428 of 21,649 [20.5%] vs 9331 of 88,525 [10.5%]).

Moreover, those identifying as Black who were hospitalized with DFU had a 21.9% rate of death or major leg amputation (4732 of 21,649), compared to the overall cohort proportion of 17.6% (n = 21,919).

In a statistical model supporting intersectionality, investigators found a significant interaction between identifying as Black and rural residence (odds ratio [OR], 1.34; 95% CI, 1.15 - 1.57).

Meanwhile, the adjusted predicted probability of major leg amputation of death for rural patients identifying as black increased to 24.7% (95% CI, 22.4% - 26.9%), when controlling for socioeconomic variables.

Brennan noted the association between rurality and major leg amputation increased after controlling for comorbidities, suggesting “the broadly defined health care system may be one of the structural forces associated with the disparities in major leg amputations.”

“Focusing efforts to improve care further upstream in ambulatory—as opposed to hospital—settings will likely prove to be particularly effective,” Brennan concluded.

The study, “Association of Race, Ethnicity, and Rurality With Major Leg Amputation or Death Among Medicare Beneficiaries Hospitalized With Diabetic Foot Ulcers,” was published in JAMA Network Open.