Impact of Diabetes Mellitus on Critical Limb Ischemia With Below the Knee Disease: Japan Below-the-Knee Artery Treatment Subanalysis

Nationwide Study of the Outcome of Treatment of Lower Extremity Atherosclerotic Lesions With Endovascular Surgery With or Without Drug Eluting Methods in Patients With Diabetes

CLINICAL IMPACT

This retrospective observational registry trial combines national registries for vascular surgical procedures and diabetes mellitus to clarify results of drug eluting technology in treating diabetic subjects with intermittent claudication or chronic limb threatening ischemia compared to treatment of non-diabetic subjects. As earlier proposed and showed in this trial, there may be an implication for a beneficial treatment efficacy with drug eluting therapy in the diabetic population with PAD compared to the non-diabetic population. A finding worth further exploration.

Diabetes mellitus and outcomes of lower extremity revascularization for peripheral artery disease

AIMS

The impact of diabetes mellitus (DM) on outcomes of lower extremity revascularization (LER) for peripheral artery disease (PAD) is uncertain. We characterized associations between DM and post-procedural outcomes in PAD patients undergoing LER.

METHODS AND RESULTS

Adults undergoing surgical or endovascular LER were identified from the 2014 Nationwide Readmissions Database. DM was defined by ICD-9 diagnosis codes and sub-classified based on the presence or absence of complications (poor glycaemic control or end-organ damage). Major adverse cardiovascular and limb events (MACLEs) were defined as the composite of death, myocardial infarction, ischaemic stroke, or major limb amputation during the index hospitalization for LER. For survivors, all-cause 6-month hospital readmission was determined. Among 39 441 patients with PAD hospitalized for LER, 50.8% had DM. The composite of MACLE after LER was not different in patients with and without DM after covariate adjustment, but patients with DM were more likely to require major limb amputation [5.5% vs. 3.2%, P < 0.001; adjusted odds ratio (aOR) 1.22, 95% confidence interval (CI) 1.03-1.44] and hospital readmission (59.2% vs. 41.3%, P < 0.001; aOR 1.44, 95% CI 1.34-1.55). Of 20 039 patients with DM hospitalized for LER, 55.7% had DM with complications. These patients were more likely to have MACLE after LER (11.1% vs. 5.2%, P < 0.001; aOR 1.56 95% CI 1.28-1.89) and require hospital readmission (61.1% vs. 47.2%, P < 0.001; aOR 1.41 95% CI 1.27-1.57) than patients with uncomplicated DM.

CONCLUSIONS

DM is present in ≈50% of patients undergoing LER for PAD and is an independent risk factor for major limb amputation and 6-month hospital readmission.

Predictors of outcome in diabetic patients undergoing infrapopliteal endovascular revascularization for chronic limb-threatening ischemia

OBJECTIVE

The incidence of chronic limb-threatening ischemia in diabetic patients is increasing. The factors influencing outcome after infrapopliteal revascularization in these patients are largely unknown. Therefore, this study aims to identify the impact of perioperative glucose control on the long-term outcomes in this patient cohort, and furthermore to identify other factors independently associated with outcome.

METHODS

Consecutive diabetic patients undergoing infrapopliteal endovascular revascularization for chronic limb-threatening ischemia were identified. Patients' demographics, procedural details, daily capillary blood glucose, and hemoglobin A1C levels were collected and analyzed against the study end points using Kaplan-Meier and Cox regression analysis.

RESULTS

A total of 437 infrapopliteal target vessels were successfully crossed in 203 patients. Amputation-free survival by Kaplan-Meier (estimate (standard error)%) was 74 (3.3)% and 63 (3.7)%, primary patency was 61 (4.2)% and 50 (4.9)%, assisted primary patency was 69 (5.2)% and 55 (6.1)%, and secondary patency was 71 (3.8)% and 59 (4.1)% at 1 year and 2 years, respectively. Cox regression analysis showed high perioperative capillary blood glucose levels to be an independent predictor of binary restenosis (hazard ratio [HR], 1.49; 95% confidence interval [CI], 1.31-1.1.78; P = .015). Postprocedural dual-antiplatelet therapy was found to be an independent predictor of amputation-free survival (HR, 1.69; 95% CI, 1.04-2.75; P = .033), and freedom from major adverse limb events (HR: 1.96; 95% CI, 1.16-3.27; P = .023) and baseline estimated glomerular filtration rate was significantly associated with better amputation-free survival (HR, 0.52; 95% CI, 0.31-0.87; P = .014).

CONCLUSIONS

Poor perioperative glycemic control is associated with a higher incidence of restenosis after infrapopliteal revascularization in diabetic patients. Dual antiplatelet therapy is associated with better outcomes in this group.

Editor's Choice - Mortality and Major Amputation after Revascularisation in Octogenarians Versus Non-Octogenarians with Chronic Limb Threatening Ischaemia: A Systematic Review and Meta-Analysis

OBJECTIVE

The aim of this systematic review and meta-analysis was to assess the clinical outcomes after revascularisation in octogenarians with chronic limb threatening ischaemia (CLTI).

METHODS

This was a systematic review and meta-analysis, in which the Medline, Embase, and Cochrane Library databases were searched systematically by two independent researchers. Meta-analyses were performed to analyse one year mortality, one year major amputation, and one year amputation free survival (AFS) after revascularisation. Pooled outcome estimates were reported as percentages and odds ratio (OR) with 95% confidence intervals (CI). In addition, sensitivity and subgroup analyses were performed and the quality of evidence was determined according to the GRADE system.

RESULTS

The review includes 21 observational studies with patients who were treated for CLTI. Meta-analysis of 12 studies with a total of 17 118 patients was performed. A mortality rate of 32% was found in octogenarians (95% CI 27-37%), which was significantly higher than in the non-octogenarians (17%, 95% CI 11-22%/OR 2.52, 95% CI 1.93-3.29; GRADE: "low"). No significant difference in amputation rate was found (octogenarians 15%, 95% CI 11-18%; non-octogenarians 12%, 95% CI 7-14%; GRADE: "very low"). AFS was significantly lower in the octogenarian group (OR 1.55, 95% CI 1.03-2.43; GRADE: "very low"). In a subgroup analysis differentiating between endovascular and surgical revascularisation, amputation rates were comparable. For octogenarians, those treated conservatively had a mortality rate significantly higher than those treated by revascularisation (OR 1.76, 95% CI 1.19-2.60; GRADE: "very low"). No significant difference in mortality rate was found between primary amputation and revascularisation in octogenarians (OR 0.70, 95% CI 0.24-2.03; GRADE: "very low").

CONCLUSION

In octogenarians with CLTI, a substantial one year mortality rate of 32% was found after revascularisation. The amputation rates were comparable between both age groups. However, only low quality evidence could be obtained supporting the results of this meta-analysis because only observational studies were available for inclusion.

Evaluation of Risk Factors for Major Amputation in Patients With Diabetes and Peripheral Artery Disease Receiving Antiplatelet Therapy - Post Hoc Analysis of a Prospective Observational Multicenter Cohort Study (SEASON)

BACKGROUND

Guidelines for peripheral arterial disease (PAD) recommend long-term antiplatelet therapy in symptomatic patients to reduce cardiovascular morbidity and mortality risk. Although diabetes is a known risk factor for PAD, PAD has been undertreated in these patients. This study aimed to evaluate risk factors for major amputation in patients with diabetes undergoing antiplatelet therapy for PAD.Methods and Results:This retrospective analysis of a 2-year observational cohort study (1,745 clinics in Japan, September 2009-2013) evaluated predictors of amputation in patients with diabetes undergoing antiplatelet therapy for PAD. Among 4,016 eligible patients, 52 had an amputation during follow-up. Amputation risk (Cox regression analysis) was predicted at baseline by history of lower extremity revascularization/amputation (hazard ratio [HR]: 2.92; 95% confidence interval [CI]: 1.39, 6.14), chronic kidney disease (HR: 4.19; 95% CI: 1.95, 8.97), and comorbid cerebrovascular and heart disease (HR: 3.32; 95% CI: 1.19, 9.30), and was unaffected by choice of oral antiplatelet therapy. In patients with PAD and diabetes, amputation event rate was highest for those with ankle-brachial pressure index (ABI) <0.40 and progressively decreased at higher ABI cut-offs.

CONCLUSIONS

These findings inform real-world understanding of PAD in diabetic patients receiving antiplatelet therapy in Japan, and showed that ABI <0.4 was the strongest risk factor for amputation.

Human diabetic mesenchymal stem cells from peripheral arterial disease patients promote angiogenesis through unique secretome signatures

BACKGROUND

Diabetic patients are at increased risk of complications from severe peripheral arterial disease. Mesenchymal stem cells (MSC) may be useful in limiting these complications. Our objective is to test the angiogenic potential of diabetic versus healthy MSCs.

METHODS

MSCs' angiogenic potential was tested by endothelial cell (EC) proliferation, migration, and 3-dimensional sprouting. Diabetic conditions were simulated with 5.5, 20, or 40 mM glucose. MSC secretome was quantified by enzyme-linked immunosorbent assay.

RESULTS

Human aortic ECs were most sensitive to glucose conditions and were used for all MSC experiments. Diabetic MSCs had greater 3-dimensional invasion than healthy MSCs (P<.05), but EC sprouting was decreased in high glucose conditions in both diabetic and healthy MSCs. Secretome analysis demonstrated that 20mM glucose stimulated epidermal growth factor (EGF) expression in diabetic and healthy MSCs, but that diabetic MSCs had a unique secretome with increased levels of chemokine (C-X-C motif) ligand 1 (CXCL-1), interleukin six (IL-6), and monocyte chemoattractant protein 1 (MCP-1) (P<.05).

CONCLUSION

Despite having similar in vitro angiogenic activity, diabetic MSCs secrete a unique and inflammatory angiogenic signature that may influence MSC survival and function after transplantation in cell therapy applications. Strategies that normalize secretome in diabetic patients may improve the utility of autologous MSCs in this population of patients.

Promoting Limb Salvage through Multi-Disciplinary Care of the Diabetic Patient

OPINION STATEMENT

Despite an explosion in the number of options available for helping diabetic patients heal wounds, major amputation remains a critical issue for these persons. Since diabetes prematurely ages tissues and no organ system is immune to its presence, it makes inherent sense that multi-disciplinary team approaches to these patients is necessary to make significant strides forward. Here, we present literature from the fields of podiatric surgery/medicine, vascular and plastic surgery and introduce the successes that a multi-disciplinary limb salvage center can have on the lives and limbs of patients with diabetes.

Impact of diabetes on outcome in critical limb ischemia with tissue loss: a large-scaled routine data analysis

BACKGROUND

Patients with diabetes concomitant to critical limb ischemia (CLI) represent a sub-group at particular risk. Objective of this analysis is to evaluate the actual impact of diabetes on treatment, outcome, and costs in a real-world scenario in Germany.

METHODS

We obtained routine-data on 15,332 patients with CLI with tissue loss from the largest German health insurance, BARMER GEK from 2009 to 2011, including a follow-up until 2013. Patient data were analyzed regarding co-diagnosis with diabetes with respect to risk profiles, treatment strategy, in-hospital and long-term outcome including costs.

RESULTS

Diabetic patients received less overall revascularizations in Rutherford grades 5 and 6 (Rutherford grade 5: 45.0 vs. 55.5%; Rutherford grade 6: 46.5 vs. 51.8; p < 0.001) and less vascular surgery (Rutherford grade 5: 13.4 vs. 23.4; Rutherford grade 6: 19.7 vs. 29.6; p < 0.001), however more often endovascular revascularization in Rutherford grade 6 (31.0 vs. 28.1; p = 0.004) compared to non-diabetic patients. Diabetes was associated with a higher observed ratio of infections (35.3 vs. 23.5% Rutherford grade 5; 44.3 vs. 27.4% Rutherford grade 6; p < 0.001) and in-hospital amputations (13.0 vs. 7.3% Rutherford grade 5; 47.5 vs. 36.7% Ruth6; p < 0.001). Diabetes further increased the risk for amputation during follow-up [Rutherford grade 5: HR 1.51 (1.38-1.67); Rutherford grade 6: HR 1.33 (1.25-1.41); p < 0.001], but not for death.

CONCLUSIONS

Diabetes increases markedly the risk of amputation attended by higher costs in CLI patients with tissue loss (OR 1.67 at Rutherford 5, OR 1.53 at Rutherford 6; p < 0.001), but is associated with lower revascularizations. However, in Rutherford grades 5 and 6, concomitant diabetes does not further worsen the overall poor survival.

Impact of diabetes on mortality in peripheral artery disease: a meta-analysis

BACKGROUND

There are accumulating studies showing the association between diabetes and all-cause mortality in peripheral vascular disease. However, the results in these studies are conflicting regarding the impact of diabetes on outcome.

HYPOTHESIS

Diabetes is associated with increased risk of mortality in peripheral artery disease.

METHODS

Using MEDLINE and Scopus, we searched for studies published before January 2016. Additionally, studies were identified by manual search of references of original articles or review studies on this topic. Of the 1072 initially identified records, 21 studies with 15,857 patients were included in the final analysis.

RESULTS

Diabetes was associated with a statistically significant increased risk of all-cause mortality (odds ratio: 1.89, 95% confidence interval: 1.51-2.35, P < 0.001), without detected publication bias (Egger bias = 0.75, P = 0.631). The stronger effect on outcome was obtained in patients with critical limb ischemia (odds ratio: 2.38, 95% confidence interval: 1.22-4.63, P < 0.001) as the most severe form of peripheral vascular disease.

CONCLUSIONS

Diabetes is associated with an increased risk of mortality in peripheral vascular disease, and the effect is even more pronounced in patients with critical limb ischemia.

Association of impaired fasting glucose, diabetes and their management with the presentation and outcome of peripheral artery disease: a cohort study

Background

Pre-diabetes and untreated diabetes are common in patients with peripheral artery disease however their impact on outcome has not been evaluated. We examined the association of impaired fasting glucose, diabetes and their treatment with the presentation, mortality and requirement for intervention in peripheral artery disease patients.

Methods

We prospectively recruited 1637 patients with peripheral artery disease, measured fasting glucose, recorded medications for diabetes and categorised them by diabetes status. Patients were followed for a median of 1.7 years.

Results

At entry 22.7% patients were receiving treatment for type 2 diabetes by oral hypoglycaemics alone (18.1%) or insulin (4.6%). 9.2% patients had non-medicated diabetes. 28.1% of patients had impaired fasting glucose (5.6-6.9 mM). Patients with non-medicated diabetes had increased mortality and requirement for peripheral artery intervention (hazards ratio 1.62 and 1.31 respectively). Patients with diabetes prescribed insulin had increased mortality (hazard ratio 1.97). Patients with impaired fasting glucose or diabetes prescribed oral hypoglycaemics only had similar outcomes to patients with no diabetes.

Conclusions

Non-medicated diabetes is common in peripheral artery disease patients and associated with poor outcomes. Impaired fasting glucose is also common but does not increase intermediate term complications. Peripheral artery disease patients with diabetes requiring insulin are at high risk of intermediate term mortality.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-014-0147-2) contains supplementary material, which is available to authorized users.

Clinical Predictors of Long-Term Outcomes in Patients With Critical Limb Ischemia Who have Undergone Endovascular Therapy

Clinical predictors of long-term outcomes in patients with critical limb ischemia (CLI) treated with endovascular therapy (EVT) remain unclear. In this study, clinical predictors of long-term outcomes in EVT-treated patients with CLI were investigated. In this prospective, observational study, we analyzed a total of 253 Taiwanese patients with CLI with 314 limbs who underwent EVT between 2005 and 2012. Cox models were used to estimate hazard ratios of death, limb loss, and sustained clinical success (SCS). Multivariate analysis showed that age, atrial fibrillation (AF), end-stage renal disease (ESRD), and albumin were significant predictors of mortality. Patients with coronary artery disease and low albumin levels had a significant risk of major limb amputation, while AF, ESRD, and albumin were significant, independent predictors of SCS. In addition to previously reported predictors, we showed that AF and malnutrition can be used to predict long-term outcome in EVT-treated patients with CLI.