Reducing Nontraumatic Lower-Extremity Amputations by 20% by 2030: Time to Get to Our Feet: A Policy Statement From the American Heart Association

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.

Injury Precipitating Tissue Loss and Time to Referral to a Vascular Center in Patients with Chronic Limb-Threatening Ischemia

AIM

This study aimed to report injury precipitating tissue loss and to provide updated information on the time from tissue loss occurrence to referral to a vascular center for patients who developed chronic limb-threatening ischemia (CLTI) in Japan.

METHODS

We examined 450 patients who developed CLTI with tissue loss and were registered in a multicenter prospective study between October 2017 and June 2020. They were referred to the participating vascular centers for revascularization. Information on the injury precipitating tissue loss and time to referral was collected at registration. The severity of tissue loss was evaluated using the Wound, Ischemia, and foot Infection classification.

RESULTS

Injury precipitating tissue loss was absent in 52.0% (95% confidence interval, 47.3%-56.6%) of the patients. The absence was associated with lower albumin levels and preserved pressure sensation. Although the time to referral was significantly shorter in cases without a history of prereferral revascularization, 16.8% (12.8%-20.7%) of the patients were referred to the vascular centers more than 3 months after tissue loss occurrence. Time to referral, but not the lack of a clear precipitant for tissue loss, was significantly associated with the severity of tissue loss.

CONCLUSION

A clear precipitant for tissue loss was often lacking, particularly in patients with low albumin levels and preserved pressure sensation. Delayed referral to a vascular center is still common.

Racial and ethnic disparities in major adverse limb events persist for chronic limb threatening ischemia despite presenting limb threat severity after peripheral vascular intervention

OBJECTIVE

Racial and ethnic disparities have been well-documented in the outcomes for chronic limb threatening ischemia (CLTI). One purported explanation has been the disease severity at presentation. We hypothesized that the disparities in major adverse limb events (MALE) after peripheral vascular intervention (PVI) for CLTI would persist despite controlling for disease severity at presentation using the WIfI (Wound, Ischemia, foot Infection) stage.

METHODS

The Vascular Quality Initiative PVI dataset (2016-2021) was queried for CLTI. Patients were excluded if they were missing the WIfI stage. The primary end point was the incidence of 1-year MALE, defined as major amputation (through the tibia or fibula or more proximally) or reintervention (endovascular or surgical) of the initial treatment limb. A multivariate hierarchical Fine-Gray analysis was performed, controlling for hospital variation, competing risk of death, and presenting WIfI stage, to assess the independent association of Black/African American race and Latinx/Hispanic ethnicity with MALE. A Cox proportional hazard regression model was used for the 1-year survival analysis.

RESULTS

Overall, 47,830 patients (60%) had had WIfI scores reported (73% White, 20% Black, and 7% Latinx). The 1-year unadjusted cumulative incidence of MALE was 13.1% (95% confidence interval [CI], 12.6%-13.5%) for White, 14.3% (95% CI, 13.5%-15.3%) for Black, and 17.0% (95% CI, 15.3%-18.9%) for Latinx patients. On bivariate analysis, the occurrence of MALE was significantly associated with younger age, Black race, Latinx ethnicity, coronary artery disease, cerebrovascular disease, congestive heart failure, hypertension, diabetes, dialysis, intervention level, any prior minor or major amputation, and WIfI stage (P < .001). The cumulative incidence of 1-year MALE increased by increasing WIfI stage: stage 1, 11.7% (95% CI, 10.9%-12.4%); stage 2, 12.4% (95% CI, 11.8%-13.0%); stage 3, 14.8% (95% CI, 13.8%-15.8%); and stage 4, 15.4% (95% CI, 14.3%-16.6%). The cumulative incidence also increased by intervention level: inflow, 10.7% (95% CI, 9.8%-11.7%), femoropopliteal, 12.3% (95% CI, 11.7%-12.9%); and infrapopliteal, 14.1% (95% CI, 13.5%-14.8%). After adjustment for WIfI stage only, Black race (subdistribution hazard ratio [SHR], 1.30; 95% CI, 1.17-1.44; P < .001) and Latinx ethnicity (SHR, 1.58; 95% CI, 1.37-1.81; P < .001) were associated with an increased 1-year hazard of MALE compared with White race. On adjusted multivariable analysis, MALE disparities persisted for Black/African American race (SHR, 1.12; 95% CI, 1.01-1.25; P = .028) and Latinx/Hispanic ethnicity (SHR, 1.34; 95% CI, 1.16-1.54; P < .001) compared with White race.

CONCLUSIONS

Black/African American and Latinx/Hispanic patients had a higher associated hazard of MALE after PVI for CLTI compared with White patients despite an adjustment for WIfI stage at presentation. These results suggest that disease severity at presentation does not account for disparities in outcomes. Further work should focus on better understanding the underlying mechanisms for disparities in historically marginalized racial and ethnic groups presenting with CLTI.

Numerical Analysis of a Transtibial Prosthesis Socket Using 3D-Printed Bio-Based PLA

Lower-limb prosthesis design and manufacturing still rely mostly on the workshop process of trial-and-error using expensive unrecyclable composite materials, resulting in time-consuming, material-wasting, and, ultimately, expensive prostheses. Therefore, we investigated the possibility of utilizing Fused Deposition Modeling 3D-printing technology with inexpensive bio-based and bio-degradable Polylactic Acid (PLA) material for prosthesis socket development and manufacturing. The safety and stability of the proposed 3D-printed PLA socket were analyzed using a recently developed generic transtibial numeric model, with boundary conditions of donning and newly developed realistic gait cycle phases of a heel strike and forefoot loading according to ISO 10328. The material properties of the 3D-printed PLA were determined using uniaxial tensile and compression tests on transverse and longitudinal samples. Numerical simulations with all boundary conditions were performed for the 3D-printed PLA and traditional polystyrene check and definitive composite socket. The results showed that the 3D-printed PLA socket withstands the occurring von-Mises stresses of 5.4 MPa and 10.8 MPa under heel strike and push-off gait conditions, respectively. Furthermore, the maximum deformations observed in the 3D-printed PLA socket of 0.74 mm and 2.66 mm were similar to the check socket deformations of 0.67 mm and 2.52 mm during heel strike and push-off, respectively, hence providing the same stability for the amputees. We have shown that an inexpensive, bio-based, and bio-degradable PLA material can be considered for manufacturing the lower-limb prosthesis, resulting in an environmentally friendly and inexpensive solution.

Surgery or Endovascular Therapy for Chronic Limb-Threatening Ischemia

BACKGROUND

Patients with chronic limb-threatening ischemia (CLTI) require revascularization to improve limb perfusion and thereby limit the risk of amputation. It is uncertain whether an initial strategy of endovascular therapy or surgical revascularization for CLTI is superior for improving limb outcomes.

METHODS

In this international, randomized trial, we enrolled 1830 patients with CLTI and infrainguinal peripheral artery disease in two parallel-cohort trials. Patients who had a single segment of great saphenous vein that could be used for surgery were assigned to cohort 1. Patients who needed an alternative bypass conduit were assigned to cohort 2. The primary outcome was a composite of a major adverse limb event - which was defined as amputation above the ankle or a major limb reintervention (a new bypass graft or graft revision, thrombectomy, or thrombolysis) - or death from any cause.

RESULTS

In cohort 1, after a median follow-up of 2.7 years, a primary-outcome event occurred in 302 of 709 patients (42.6%) in the surgical group and in 408 of 711 patients (57.4%) in the endovascular group (hazard ratio, 0.68; 95% confidence interval [CI], 0.59 to 0.79; P<0.001). In cohort 2, a primary-outcome event occurred in 83 of 194 patients (42.8%) in the surgical group and in 95 of 199 patients (47.7%) in the endovascular group (hazard ratio, 0.79; 95% CI, 0.58 to 1.06; P = 0.12) after a median follow-up of 1.6 years. The incidence of adverse events was similar in the two groups in the two cohorts.

CONCLUSIONS

Among patients with CLTI who had an adequate great saphenous vein for surgical revascularization (cohort 1), the incidence of a major adverse limb event or death was significantly lower in the surgical group than in the endovascular group. Among the patients who lacked an adequate saphenous vein conduit (cohort 2), the outcomes in the two groups were similar. (Funded by the National Heart, Lung, and Blood Institute; BEST-CLI ClinicalTrials.gov number, NCT02060630.).

Temporal Trends, Practice Variation, and Associated Outcomes With IVUS Use During Peripheral Arterial Intervention

BACKGROUND

Intravascular ultrasound (IVUS) has been shown in limited prospective studies to improve procedural outcomes for patients undergoing lower extremity peripheral arterial intervention (PVI).

OBJECTIVES

The authors aimed to study temporal trends, practice variation, and associated outcomes with the use of IVUS during PVI among Medicare beneficiaries.

METHODS

All PVIs performed from 2016 to 2019 among Medicare beneficiaries aged >65 years were included. Temporal trends in IVUS use were stratified by procedural location (inpatient, outpatient, or ambulatory surgery center [ASC]/office-based laboratory [OBL]) and physician specialty. The primary outcome was major adverse limb events (MALE). Inverse probability weighting was used to account for differences in baseline characteristics. Cox regression with competing risks was used to estimate weighted hazard ratios.

RESULTS

During the study period, 543,488 PVIs were included, of which 63,372 (11.7%) used IVUS. A substantial growth in IVUS use was observed, which was driven by procedures performed in ASCs/OBLs (23.6% increase from quarter 1 of 2016 through quarter 4 of 2019). Among operators who used IVUS, there was also notable variation in use (median operator use 5.4% of cases; IQR: 2.2%-15.0%; range, <1%-100%). In weighted analysis, IVUS use during PVI was associated with a lower risk of MALE through a median of 514 days (adjusted hazard ratio: 0.73; 95% CI: 0.70-0.75; P < 0.0001).

CONCLUSIONS

In contemporary nationwide data, IVUS use during PVI has increased since 2016, driven by growth in the ASC/OBL setting. However, there remains substantial variation in operator practice. When used during PVI, IVUS was associated with a lower risk of short- and long-term MALE.

Knowledge, attitude and perception towards lower limb amputation amongst persons living with diabetes in rural South Africa: A qualitative study

Background

South Africa has a high prevalence of diabetes mellitus (DM), a leading risk factor for lower limb amputation (LLA). Lower limb amputation is associated with significant morbidity and mortality. Lower limb amputation incidence can be mitigated through prompt identification and treatment of individuals at risk and engagement in self-management practices. Also, when LLA is inevitable, outcomes or prognosis can be improved with timely surgery.

Aim

This study explored the knowledge, attitude and perception of persons living with diabetes towards LLA and its prevention.

Setting

Nqamakwe, a rural community in the Eastern Cape province of South Africa.

Method

This was a descriptive, qualitative study involving persons living with DM, with and without LLA, and community leaders. Fifteen participants were recruited purposively and conveniently from a rural community in the Eastern Cape, South Africa. Data collection took place through semistructured interviews, in English and a local language, Xhosa. Interviews were transcribed and translated, and an inductive approach was used for thematic analysis.

Results

A total of 15 individual interviews were conducted. Of those, 13 were persons with DM, five with LLA, including one with bilateral LLA. There was a gap in knowledge on foot self-examination as a measure of preventing LLA amongst persons with DM. The attitude of persons without LLA was mostly fearful and their fears centred around perioperative death, risk for contralateral amputation, loss of limb and independence. Consent to LLA procedure was a last resort and only when pain levels were unbearable. Family support and information on rehabilitation services and assistive devices also fostered consent to LLA surgery.

Conclusion

There is a need for awareness creation and adequate health education for persons living with DM on LLA and its prevention measures, especially foot care practices. Also, health education programmes for persons living with DM in rural areas should address the various misperceptions of LLA to reduce delays.

Contribution

The article revealed gaps in knowledge on LLA and its prevention among individuals living with diabetes as well as areas of concerns that may potentially delay acceptance when LLA is inevitable. Findings from our study may assist primary health care providers to determine important issues to be addressed during routine and pre-operative patient education.

Peripheral artery disease and the risk of venous thromboembolism

Summary: Background: Peripheral artery disease (PAD) impacts 3–12% of patients worldwide and is characterized by endothelial dysfunction and inflammatory pathways which are also common to venous thromboembolism (VTE), but there is a paucity of evidence regarding VTE risk in PAD patients. We investigated whether PAD is an independent risk factor for VTE. Patients and methods: We reviewed medical records of patients undergoing ABI studies at Mayo Clinic from 01/1996-02/2020. We classified patients by ABI (low [<1.0], normal [1.0–1.4], or elevated [>1.4]), as well as by specific low ABI subgroup: severely reduced (ABI: 0.00–0.39), moderately reduced (0.40–0.69), mildly reduced (0.70–0.90), and borderline reduced (0.91–0.99). The primary outcome was incident VTE event (acute lower extremity deep vein thrombosis or pulmonary embolism) after ABI measurement. Multivariable Cox proportional regression was used to calculate hazard ratios (HR) with 95% confidence intervals (CI) after adjusting for age, sex, active smoking, cancer, previous VTE, thrombophilia, anticoagulation, and revascularization. Results: 39,834 unique patients (mean age 66.3±14.3 years, median follow-up 34 months) were identified. 2,305 VTE events occurred in patients without PAD (13.0%), 2,218 in low ABI patients (13.0%), and 751 in elevated ABI patients (14.8%). After risk factor adjustment, VTE risk was modestly increased for PAD overall (HR: 1.12, 95% CI [1.06, 1.18]), including low ABI (HR: 1.11, 95% CI [1.04, 1.18]) and elevated ABI groups (HR: 1.15, 95% CI [1.04, 1.26]), compared to patients without PAD. The greatest VTE risk was in severely low ABI patients (HR: 1.46, 95% CI [1.31, 1.64]). Conclusions: In a large longitudinal cohort, we present strong clinical evidence of PAD, with low and elevated ABI, as an independent VTE risk factor, with the highest risk seen in patients with severely low ABI. Continued research is required to further investigate this relationship and its intersection with functional performance status to optimize VTE risk reduction or anticoagulation strategies in the PAD population.

Differences in Comorbidities Explain Black-White Disparities in Outcomes After Femoropopliteal Endovascular Intervention

BACKGROUND

Black adults have a higher incidence of peripheral artery disease and limb amputations than White adults in the United States. Given that peripheral endovascular intervention (PVI) is now the primary revascularization strategy for peripheral artery disease, it is important to understand whether racial differences exist in PVI incidence and outcomes.

METHODS

Data from fee-for-service Medicare beneficiaries ≥66 years of age from 2016 to 2018 were evaluated to determine age- and sex-standardized population-level incidences of femoropopliteal PVI among Black and White adults over the 3-year study period. Patients' first inpatient or outpatient PVIs were identified through claims codes. Age- and sex-standardized risks of the composite outcome of death and major amputation within 1 year of PVI were examined by race.

RESULTS

Black adults underwent 928 PVIs per 100 000 Black beneficiaries compared with 530 PVIs per 100 000 White beneficiaries (risk ratio, 1.75 [95% CI, 1.73-1.77]; P<0.01). Black adults who underwent PVI were younger (mean age, 74.5 years versus 76.4 years; P<0.01), were more likely to be female (52.8% versus 42.7%; P<0.01), and had a higher burden of diabetes (70.6% versus 56.0%; P<0.01), chronic kidney disease (67.5% versus 56.6%; P<0.01), and heart failure (47.4% versus 41.7%; P<0.01) than White adults. When analyzed by indication for revascularization, Black adults were more likely to undergo PVI for chronic limb-threatening ischemia than White adults (13 023 per 21 352 [61.0%] versus 59 956 per 120 049 [49.9%]; P<0.01). There was a strong association between Black race and the composite outcome at 1 year (odds ratio, 1.21 [95% CI, 1.16-1.25]). This association persisted after adjustment for socioeconomic status (odds ratio, 1.08 [95% CI, 1.03-1.13]) but was eliminated after adjustment for comorbidities (odds ratio, 0.96 [95% CI, 0.92-1.01]).

CONCLUSIONS

Among fee-for-service Medicare beneficiaries, Black adults had substantially higher population-level PVI incidence and were significantly more likely to experience adverse events after PVI than White adults. The association between Black race and adverse outcomes appears to be driven by a higher burden of comorbidities. This analysis emphasizes the critical need for early identification and aggressive management of peripheral artery disease risk factors and comorbidities to reduce Black-White disparities in the development and progression of peripheral artery disease and the risk of adverse events after PVI.

Lower Extremity Amputations Among Veterans: Have Ambulatory Outcomes and Survival Improved?

OBJECTIVE

We hypothesize among patients undergoing lower extremity amputation, access to pre, and post operative rehabilitation services; as well as improved medical care, have led to higher rates of postoperative ambulation, and improved survival.

METHODS

Retrospective single center review of all major lower extremity amputations performed at the Greater Los Angeles Veterans Affairs Healthcare System from 2000 - 2020 stratified into multiyear cohorts. We abstracted demographics, operative indication, comorbidities, preoperative medical management, perioperative complications, discharge location, and pre- and postoperative ambulatory status. Odds of ambulation after amputation were analyzed using multivariate logistic regression. Survival was analyzed using multivariate logistic regression and Kaplan-Meier survival analysis. Multivariate logistic predictors were selected based on prior literature and clinical experience.

RESULTS

We identified 654 operations in our study, noting less amputations performed in the latest three cohort years as compared to the initial cohort (2000 - 2004). Patients undergoing below-knee amputations (BKA) had 2.7 times (p < 0.05) greater odds of postoperative ambulation and 86% (p < 0.05) increased odds of survival compared to above-knee amputations (AKA). The odds of ambulation increased by 8.8% (p < 0.05) for each consecutive study year. Ambulation post-amputation conferred 13.2 times (p < 0.05) greater odds of survival. The odds of survival in "emergent" operations decreased by 48% (p < 0.05) compared to an "elective" operation. For each additional comorbidity, the odds of survival decreased by 18% (p < 0.05). Patients with any perioperative complication had a 48% (p < 0.05) lower odds of survival. Kaplan Meier survival estimates demonstrated significant survival difference between patients by amputation level and postoperative ambulatory status (p < 0.05).

CONCLUSIONS

Ambulatory status following distal amputation has improved over time and is significantly associated with increased survival post-amputation. Patients undergoing a BKA or discharged home were most likely to ambulate postoperatively. Amputation level, preoperative comorbidities, and perioperative complications remain strong predictors of survival.

Disparities In Diabetes-Related Lower Extremity Amputations In The United States: A Systematic Review

Disparities in rates of peripheral diabetic neuropathy and lower extremity amputation exist in the United States. To investigate the factors linked to this disparity, we performed a systematic review of the literature on the subject published during the period 2000-20. Nineteen observational studies were included. Disparities in rates of lower extremity amputation were reported according to patient race, ethnicity, sex, and age; across hospital referral regions, residential area characteristics, and income estimates; and on the basis of payer type and hospital characteristics. Several of these factors were interrelated. There was a reduction in major lower extremity amputation rates among Black, Hispanic, and White patients with diabetes over time, suggesting narrowing disparities in the odds of this procedure among Black and White patients. There is a need for a national strategy that integrates public awareness, screening, early initiated multidisciplinary care, and quality measures for peripheral artery disease management, as well as neighborhood-level public health interventions, to reduce the disproportionate burden of lower extremity amputation in underserved communities.

PBMNCs Treatment in Critical Limb Ischemia and Candidate Biomarkers of Efficacy

When in critical limb ischemia (CLI) the healing process aborts or does not follow an orderly and timely sequence, a chronic vascular wound develops. The latter is major problem today, as their epidemiology is continuously increasing due to the aging population and a growth in the incidence of the underlying diseases. In the US, the mean annualized prevalence of necrotic wounds due to the fact of CLI is 1.33% (95% CI, 1.32–1.34%), and the cost of dressings alone has been estimated at USD 5 billion per year from healthcare budgets. A promising cell treatment in wound healing is the local injection of peripheral blood mononuclear cells (PBMNCs). The treatment is aimed to induce angiogenesis as well to switch inflammatory macrophages, called the M1 phenotype, into anti-inflammatory macrophages, called M2, a phenotype devoted to tissue repair. This mechanism is called polarization and is a critical step for the healing of all human tissues. Regarding the clinical efficacy of PBMNCs, the level of evidence is still low, and a considerable effort is necessary for completing the translational process toward the patient bed site. From this point of view, it is crucial to identify some candidate biomarkers to detect the switching process from M1 to M2 in response to the cell treatment.

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.

Comparative mortality according to peripheral artery disease and coronary heart disease/stroke in the United States

BACKGROUND AND AIMS

A recent trial reported that patients with peripheral artery disease (PAD) without coronary heart disease or stroke (CHD/stroke) had worse prognosis than those with CHD/stroke without PAD. However, community-based data are lacking. The purpose of this study was to compare mortality according to the status of PAD and CHD/stroke in the general population.

METHODS

In 6780 participants (aged ≥40 years) from the National Health and Nutrition Examination Surveys 1999-2004, we compared mortality risk according to PAD (ankle-brachial index ≤0.9) and CHD/stroke (self-report) at baseline using the Kaplan-Meier method and multivariable Cox models accounting for sampling weights.

RESULTS

The prevalence of having both PAD and CHD/stroke was 1.6%. The prevalence of PAD without CHD/stroke and CHD/stroke without PAD was 4.1% and 8.5%, respectively (85.8% without PAD or CHD/stroke). Over a median follow-up of 12.8 years, 21.2% died. Individuals with both PAD and CHD/stroke had the worst survival (25.5% at 12 years). Those with PAD without CHD/stroke had the second worst prognosis (47.7%), followed by those with CHD/stroke without PAD (53.2%) and those without CHD/stroke or PAD (87.2%). Adjusted hazard ratio of mortality was 2.70 (95% CI, 2.07-3.53) for PAD with CHD/stroke, 1.81 (1.54-2.12) in CHD/stroke without PAD, and 1.68 (1.35-2.08) in PAD without CHD/stroke vs. no CHD/stroke or PAD.

CONCLUSIONS

In the US adults, PAD contributed to increased mortality in persons with and without CHD/stroke. The prognosis of PAD without CHD/stroke was no better than that of CHD/stroke without PAD. These results suggest the importance of recognizing the presence of PAD in the community.

Lower limb amputations among individuals living with diabetes mellitus in low- and middle-income countries: A systematic review protocol

Background

The burden of diabetes mellitus (DM) and its associated complications continue to burgeon, particularly in low- and middle-income countries (LMICs). Lower limb amputation (LLA) is one of the most life-altering complications of DM, associated with significant morbidity, mortality and socio-economic impacts. High-income countries have reported a decreasing incidence of DM-associated LLA, but the situation in many LMICs is unknown. We aim to conduct a systematic review to determine the incidence and prevalence of DM-associated LLA in LMICs to better inform appropriate interventions and health system response.

Methods and analysis

A systematic search of the literature will be conducted on five databases: MEDLINE, Embase, Cumulative Index of Nursing and Allied Health Literature (CINAHL), Scopus and African Journal Online (AJOL). Only observational, quantitative studies reporting the incidence and/or prevalence of DM-related LLA will be considered. A validated study design-specific critical appraisal tool will be used to assess the risk of bias in individual studies. We will determine the incidence of LLA by examining the number of new cases of LLA among individuals with confirmed DM diagnosis during the specified period, while the prevalence will be based on the total number of all new and existing LLAs in a population. LLA will be considered as the resection of the lower limb from just above the knee to any point down to the toe. If heterogeneity is low to moderate, a random-effects meta-analysis will be conducted on extracted crude prevalence/incidence rates, with the median and interquartile range also reported. The systematic review will be performed in accordance with the JBI guideline for prevalence and incidence review. Study reporting will follow the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guideline.

Prospero registration number

CRD42021238656.

Smoking cessation: health system challenges and opportunities

The systematic integration of evidence-based tobacco treatment has yet to be broadly viewed as a standard-of-care. The Framework Convention on Tobacco Control recommends the provision of support for tobacco cessation. We argue that the provision of smoking cessation services in clinical settings is a fundamental clinical responsibility and permits the opportunity to more effectively assist with cessation. The role of clinicians in prioritising smoking cessation is essential in all settings. Clinical benefits of implementing cessation services in hospital settings have been recognised for three decades-but have not been consistently provided. The Ottawa Model for Smoking Cessation has used an 'organisational change' approach to its introduction and has served as the basis for the introduction of cessation programmes in hospital and primary care settings in Canada and elsewhere. The significance of smoking cessation dwarfs that of many preventive interventions in primary care. Compelling evidence attests to the importance of providing cessation services as part of cancer treatment, but implementation of such programmes has been slow. We recognise that the provision of such services must reflect the realities and resources of a particular health system. In low-income and middle-income countries, access to treatment facilities pose unique challenges. The integration of cessation programmes with tuberculosis control services may offer opportunities; and standardisation of peri-operative care to include smoking cessation may not require additional resources. Mobile phones afford unique opportunities for interactive cessation programming. Health system change is fundamental to improving the provision of cessation services; clinicians can be powerful advocates for such change.

Lower Limb Amputation Rates in Germany

Background and Objectives: The current epidemiology of lower limb amputations is unknown. Therefore, the purpose of this study was to determine (1) lower extremity amputation rates as a function of age, gender, and amputation level between 2015 and 2019, (2) main diagnoses indicating amputation, (3) revision rates after lower extremity amputation. Materials and Methods: Lower extremity amputation rates were quantified based on annual Operation and Procedure Classification System (OPS) and International Classifications of Disease (ICD)-10 codes from all German medical institutions between 2015 through 2019, provided by the Federal Statistical Office of Germany (Destatis). Results: In 2019, 62,016 performed amputations were registered in Germany. Out of these 16,452 procedures (26.5%) were major amputations and 45,564 patients (73.5%) underwent minor amputations. Compared to 2015, the incidence of major amputations decreased by 7.3% to 24.2/100,000 inhabitants, whereas the incidence of minor amputation increased by 11.8% to 67.1/100,000 inhabitants. Highest incidence was found for male patients aged 80-89 years. Patients were mainly diagnosed with peripheral arterial disease (50.7% for major and 35.7% for minor amputations) and diabetes mellitus (18.5% for major and 44.2% for minor amputations). Conclusions: Lower limb amputations remain a serious problem. Further efforts in terms of multidisciplinary team approaches and patient optimization strategies are required to reduce lower limb amputation rates.

The association between socioeconomic distress communities index and amputation among patients with peripheral artery disease

Background

Socioeconomic factors have been shown to be associated with amputation in peripheral artery disease (PAD); however, analyses have normally focused on insurance status, race, or median income. We sought to determine whether community-level socioeconomic distress was associated with major amputation and if that association differed by race.

Materials and methods

Community-level socioeconomic distress was measured using the distressed communities index (DCI). The DCI is a zip code level compositive socioeconomic score (0-100) that accounts for unemployment, education level, poverty rate, median income, business growth, and housing vacancies. A distressed community was defined as a zip code with DCI of 40 or greater. We calculated one-year risk of major amputation by DCI score for individuals with peripheral artery disease in South Carolina, 2012-2017. Treating death as competing event, we reported Fine and Gray subdistribution hazards ratios (sdHR), adjusted for patient demographic and clinical comorbidities associated with amputation. Further analyses were completed to identify potential differences in outcomes within strata of race and DCI.

Results

Among 82,848 individuals with peripheral artery disease, the one-year incidence of amputation was 3.5% (95% CI: 3.3%, 3.6%) and was significantly greater in distressed communities than non-distressed communities (3.9%; 95% CI: 3.8%, 4.1% vs. 2.4%; 95% CI: 2.2%, 2.6%). After controlling for death and adjusting for covariates, we found an increased hazard of amputation among individuals in a distressed community (sdHR: 1.25; 95% CI: 1.14, 1.37), which persisted across racial strata. However, regardless of DCI score, Black individuals had the highest incidence of amputation.

Conclusion

Socioeconomic status is independently predictive of limb amputation after controlling for demographic characteristics and clinical comorbidities. Race continues to be an important risk factor, with Black individuals having higher incidence of amputation, even in non-distressed communities, than White individuals had in distressed communities.

Treatment of Peripheral Arterial Occlusive Disease around the Globe: Malta

INTRODUCTION

Malta is a small island in the middle of the Mediterranean with a population of 514,564 inhabitants and is served by one public tertiary hospital, Mater Dei Hospital. The Vascular unit was set up in 2007. The aim of this review is to analyse the work related to peripheral arterial occlusive disease (PAOD) in Malta with an in-depth focus on amputations and revascularisation procedures since the introduction of the Vascular unit.

METHOD

Various sources of data have been interrogated to address this subject. Population and prevalence data on obesity and type II diabetes mellitus from 2003 to 2019 was obtained from the National Statistics Office, the World Health Organization, and the International Diabetes Federation, respectively. The Maltese Vascular Register (MaltaVasc), and in-hospital reports from 2003 to 2019 was used to obtain data on revascularisation procedures, major amputations and minor amputation rates in Malta.

RESULTS

Malta has one of the highest rates of obesity in Europe. In 2015, the prevalence rate was 30.6%. Similarly, data from the International Diabetes Federation Atlas showed that the prevalence rate of T2DM among adults was 14% in 2017. There was a mean of 33 open/hybrid procedures per 100,000 population (28-38, 95% confidence interval) between 2005 and 2009 and a mean of 57 endovascular procedures per 100,000 population (46-68, 95% confidence interval) during the same time-period. From 2009 to 2019, there was a mean of 16 major amputations and 78 minor amputations per 100,000 population.

CONCLUSION

A significant reduction in major amputation rates with an increase in minor amputation rates and revascularisation rates has been noted since the establishment of the vascular unit in Malta. During this period, there has been an increase in prevalence in obesity and T2DM together with an aging population.

Up and down waves of glycemic control and lower-extremity amputation in diabetes

Lower extremity amputations (LEA) are associated with a high mortality and medical expenditure. Diabetes accounts for 45% to 70% of LEA and is one of the most potent risk factors for peripheral artery diseases (PAD). The existence of a link between the recent relaxation of glycemic targets and the resurgence of LEA is suggested from the analysis of adult participants in the National Health and Nutrition Examination Survey (NHANES) between 2010 and 2015, when diabetes-related LEA increased by more than 25% associated with a decline in glycemic control. Indeed, in “the perfect wave” of NHANES, including the years 2007–2010, there was the highest number of diabetic people with hemoglobin A1c (HbA1c), non-high-density lipoprotein (HDL) cholesterol and blood pressure levels at their respective targets, associated with the lowest number of LEA. Until now, the ACCORD study, testing the role of aggressive vs conventional glucose control, and the LEADER trial, evaluating the effects of liraglutide versus placebo, have shown a reduced incidence of LEA in people with type 2 diabetes. The results of ongoing clinical trials involving glucagon-like peptide-1 receptor agonists (GLP-1RA, liraglutide or semaglutide) hopefully will tell us whether the wider use of these drugs may provide additional vascular benefits for diabetic people affected by PAD to decrease their risk of LEA.

Contemporary Medical Management of Peripheral Artery Disease

Peripheral artery disease (PAD) is a manifestation of systemic atherosclerosis. Modifiable risk factors including cigarette smoking, dyslipidemia, diabetes, poor diet quality, obesity, and physical inactivity, along with underlying genetic factors contribute to lower extremity atherosclerosis. Patients with PAD often have coexistent coronary or cerebrovascular disease, and increased likelihood of major adverse cardiovascular events, including myocardial infarction, stroke and cardiovascular death. Patients with PAD often have reduced walking capacity and are at risk of acute and chronic critical limb ischemia leading to major adverse limb events, such as peripheral revascularization or amputation. The presence of polyvascular disease identifies the highest risk patient group for major adverse cardiovascular events, and patients with prior critical limb ischemia, prior lower extremity revascularization, or amputation have a heightened risk of major adverse limb events. Medical therapies have demonstrated efficacy in reducing the risk of major adverse cardiovascular events and major adverse limb events, and improving function in patients with PAD by modulating key disease determining pathways including inflammation, vascular dysfunction, and metabolic disturbances. Treatment with guideline-recommended therapies, including smoking cessation, lipid lowering drugs, optimal glucose control, and antithrombotic medications lowers the incidence of major adverse cardiovascular events and major adverse limb events. Exercise training and cilostazol improve walking capacity. The heterogeneity of risk profile in patients with PAD supports a personalized approach, with consideration of treatment intensification in those at high risk of adverse events. This review highlights the medical therapies currently available to improve outcomes in patients with PAD.

Advances in Revascularization for Peripheral Artery Disease: Revascularization in PAD

Effective revascularization of the patient with peripheral artery disease is about more than the procedure. The approach to the patient with symptom-limiting intermittent claudication or limb-threatening ischemia begins with understanding the population at risk and variation in clinical presentation. The urgency of revascularization varies significantly by presentation; from patients with intermittent claudication who should undergo structured exercise rehabilitation before revascularization (if needed) to those with acute limb ischemia, a medical emergency, who require revascularization within hours. Recent years have seen the rapid development of new tools including wires, catheters, drug-eluting technology, specialized balloons, and biomimetic stents. Open surgical bypass remains an important option for those with advanced disease. The strategy and techniques employed vary by clinical presentation, lesion location, and lesion severity. There is limited level 1 evidence to guide practice, but factors that determine technical success and anatomic durability are largely understood and incorporated into decision-making. Following revascularization, medical therapy to reduce adverse limb outcomes and a surveillance plan should be put in place. There are many hurdles to overcome to improve the efficacy of lower extremity revascularization, such as restenosis, calcification, microvascular disease, silent embolization, and tools for perfusion assessment. This review highlights the current state of revascularization in peripheral artery disease with an eye toward technologies at the cusp, which may significantly impact current practice.

Racial and Ethnic Disparities in Peripheral Artery Disease

Peripheral artery disease is an obstructive, atherosclerotic disease of the lower extremities causing significant morbidity and mortality. Black Americans are disproportionately affected by this disease while they are also less likely to be diagnosed and promptly treated. The consequences of this disparity can be grim as Black Americans bear the burden of lower extremity amputation resulting from severe peripheral artery disease. The risk factors of peripheral artery disease and how they differentially affect certain groups are discussed in addition to a review of pharmacological and nonpharmacological treatment modalities. The purpose of this review is to highlight health care inequities and provide a review and resource of available recommendations for clinical management of all patients with peripheral artery disease.

Lower extremity reamputation in people with diabetes: a systematic review and meta-analysis

In this study, we determined the reamputation-free survival to both limbs and to the contralateral limb only following an index amputation of any-level and assessed whether reamputation rates have changed over time. We completed a systematic search using PubMed and screened a total of 205 articles for data on reamputation rates. We reported qualitative characteristics of 56 studies that included data on reamputation rates and completed a meta-analysis on 22 of the studies which enrolled exclusively participants with diabetes. The random-effects meta-analysis fit a parametric survival distribution to the data for reamputations to both limbs and to the contralateral limb only. We assessed whether there was a temporal trend in the reamputation rate using the Mann-Kendall test. Incidence rates were high for reamputation to both limbs and to the contralateral limb only. At 1 year, the reamputation rate for all contralateral and ipsilateral reamputations was found to be 19% (IQR=5.1%-31.6%), and at 5 years, it was found to be 37.1% (IQR=27.0%-47.2%). The contralateral reamputation rate at 5 years was found to be 20.5% (IQR=13.3%-27.2%). We found no evidence of a trend in the reamputation rates over more than two decades of literature analyzed. The incidence of lower extremity reamputation is high among patients with diabetes who have undergone initial amputations secondary to diabetes, and rates of reamputation have not changed over at least two decades.