Association of neighbourhood deprivation with risks of major amputation and death following lower limb revascularisation

Impact of Regional Differences and Neighborhood Socioeconomic Deprivation on the Outcomes of Patients with Lower Extremity Wounds Evaluated by a Limb-Preservation Service

INTRODUCTION

Management of lower extremity (LE) wounds has evolved with the establishment of specialized limb preservation services. While clinical factors contribute to limb outcomes, socioeconomic status and community factors also influence the risk for limb loss. The Distressed Community Index (DCI) score is a validated index of social deprivation created to provide an objective measure of economic well-being in U.S communities. Few studies have examined the influence of geographic deprivation on outcomes in patients with LE wounds. We examined relationships between socioeconomic deprivation and outcomes of inpatients evaluated by a dedicated limb preservation service (FLEX).

METHODS

Inpatients referred to FLEX over a 5-year period were included. Wound, Ischemia, foot Infection (WIfI) staging was collected. DCI scores were determined using 7 indices based on ZIP Code. Outcomes included any minor or major amputations, any endovascular or open LE revascularization, or wound care procedures. Disease etiology, demographic, and anthropometric data were collected. Associations between neighborhood deprivation and limb-specific outcomes were evaluated in models for the DCI and each of its components separately.

RESULTS

677 patients were included. Thirty-eight percent were female, with a mean age of 64 years. Sixty percent had WIfI stage 3 or 4 risk of amputation, and 43% had WIfI stage 3 or 4 risk of revascularization. Mean (SD) ABI and toe pressure were 0.96 (0.43) and 80 (57) mmhg. Thirty-five percent were non-white. Amputation was performed in 31% of patients while 17% underwent revascularization. The mean (SD) distress score was 64 (24). Mean DCI scores did not differ across WIfI scores. Likewise, overall DCI distress score was not related to any of the outcomes in univariable or multivariable LR models. In univariable LR models for amputation, higher poverty rate (odds ratio (OR) for SD increase 1.20, 95% confidence limits (CL) 1.02-1.42, P=0.025) was significantly associated with the outcome. In multivariable models, neither DCI distress score nor any of its components remained significantly associated with the outcome.

CONCLUSIONS

Despite known racial disparities in limb-specific outcomes, an aggregate measure of community level distress was not found to be related to outcomes. While poverty rate demonstrated a significant relationship with amputation in univariable analysis, this association was not found in multivariable models. Notably, non-white race emerged as a predictor of amputation, underscoring the importance of addressing racial disparities in LE outcomes. Further investigation of potential determinants of LE outcomes is needed, particularly the interaction of such factors with race.

Towards uniform case-identification criteria in observational studies on peripheral arterial disease: A scoping review

OBJECTIVE

The diagnosis peripheral arterial disease (PAD) is commonly applied for symptoms related to atherosclerotic obstructions in the lower extremity, though its clinical manifestations range from an abnormal Ankle Brachial Index to critical limb ischemia. Subsequently, management and prognosis of PAD vary widely with the disease stage. A critical aspect is how this variation is addressed in administrative databases-based studies that rely on diagnosis codes for case identification. The objective of this scoping review is to inventory the identification strategies used in studies on PAD that rely on administrative databases, to map the pros and cons of the ICD codes applied, and propose a first outline for a consensus framework for case identification in administrative databases.

METHODS

Registry-based reports published between 2010 to 2021 were identified through a systematic PubMed search. Studies were sub-categorized on the basis of the expressed study focus: claudication, critical limb ischemia, or general peripheral arterial disease and the ICD code(s) applied for case identification mapped.

RESULTS

Ninety studies were identified, of which thirty-six (40%) did not specify the grade of PAD studied. Forty-nine (54%) articles specified PAD grade studied. Five (6%) articles specified different PAD subgroups in methods and baseline demographics, but not in further analyses. Mapping of the ICD codes applied for case identification for studies that specified the PAD grade studied indicated a remarkable heterogeneity, overlap, and inconsistency.

CONCLUSION

A large proportion of registry-based studies on PAD fails to define the study focus. In addition, inconsistent strategies are used for PAD case-identification in studies that report a focus. These findings challenge study validity, and interfere with inter-study comparison. This scoping review provides a first initiative for a consensus framework for standardized case selection in administrative studies on PAD. It is anticipated that more uniform coding will improve study validity, and facilitate inter-study comparisons.

Racial, ethnic, and socioeconomic inequities in amputation risk for patients with peripheral artery disease and diabetes

Peripheral artery disease and diabetes are highly prevalent diseases and the leading cause of limb loss. Despite advances in medical and surgical techniques, there are stark differences in delivery and outcomes of lower extremity amputation among populations when stratified by race, ethnicity, and socioeconomic status. We reviewed studies from the last 2 decades (1999-2022) to provide a comprehensive assessment of the current impact of disparities on the risk for, and management of, lower extremity amputation and offer action items that can optimize health outcomes.

Spatial analysis of factors impacting lower limb major amputation rates in Hungary

Summary: Background: Lower limb major amputations represent a substantial public health burden in Hungary, where previous research revealed markedly high rates with significant spatial variations. Therefore, we aimed to assess to what extent healthcare and socio-economic factors in the local environment explain the regional disparity. Patients and methods: In a retrospective cohort analysis, based on the healthcare administrative data of the Hungarian population, lower limb major amputations were identified from 1st of January 2017 to 31st of December 2019. The permanent residence of the amputees on the local administrative level (197 geographic units) was used to identify potential healthcare (outpatient care, revascularisation activity) and socio-economic (educational attainment, local infrastructure and services, income and employment) determinants of amputations. Spatial effects were modelled using the spatial Durbin error regression model. Results: 10,209 patients underwent 11,649 lower limb major amputations in the observational period. In our spatial analysis, outpatient care was not associated with local amputation rates. However, revascularisation activity in a geographic unit entailed an increased rate of amputations, while revascularisations in the neighbouring areas were associated with a lower rate of amputations, resulting in an overall neutral effect (β=−0.002, 95% CI: −0.05 – 0.04, p=0.96). The local socio-economic environment had a significant direct inverse association with amputations (β=−7.45, 95% CI: −10.50 – −4.42, p<0.0001) . Our spatial model showed better performance than the traditional statistical modelling (ordinary least squares regression), explaining 37% of the variation in amputations rates. Conclusions: Regional environmental factors explain a substantial portion of spatial disparities in amputation practice. While the socio-economic environment shows a significant inverse relationship with the regional amputation rates, the impact of the local healthcare-related factors (outpatient care, revascularisation activity) is not straightforward. Unravelling the impact of the location on amputation practice requires complex spatial modelling, which may guide efficient healthcare policy decisions.

Income Deprivation and Groin Wound Surgical Site Infection: Cross-Sectional Analysis from the Groin Wound Infection after Vascular Exposure Multicenter Cohort Study

Background: Living in deprived areas is associated with poorer outcomes after certain vascular procedures and surgical site infection in other specialties. Our primary objective was to determine whether living in more income-deprived areas was associated with groin wound surgical site infection after arterial intervention. Secondary objectives were to determine whether living in more income-deprived areas was associated with mortality and clinical consequences of surgical site infection. Methods: Postal code data for patients from the United Kingdom who were included in the Groin Wound Infection after Vascular Exposure (GIVE) multicenter cohort study was used to determine income deprivation, based on index of multiple deprivation (IMD) data. Patients were divided into three IMD groups for descriptive analysis. Income deprivation score was integrated into the final multivariable model for predicting surgical site infection. Results: Only patients from England had sufficient postal code data, analysis included 772 groin incisions (624 patients from 22 centers). Surgical site infection occurred in 9.7% incisions (10.3% of patients). Surgical site infection was equivalent between income deprivation tertiles (tertile 1 = 9.5%; tertile 2 = 10.3%; tertile 3 = 8.6%; p = 0.828) as were the clinical consequences of surgical site infection and mortality. Income deprivation was not associated with surgical site infection in multivariable regression analysis (odds ratio [OR], 0.574; 95% confidence interval [CI], 0.038-8.747; p = 0.689). Median age at time of procedure was lower for patients living in more income-deprived areas (tertile 1 = 68 years; tertile 2 = 72 years; tertile 3 = 74 years; p < 0.001). Conclusions: We found no association between living in an income-deprived area and groin wound surgical site infection, clinical consequences of surgical site infection and mortality after arterial intervention. Patients living in more income-deprived areas presented for operative intervention at a younger age, with similar rates of comorbidities to patients living in less income-deprived areas.