Mortality of first-time amputees in diabetics: a 10-year observation

Effect of MNCQQ Cells on Migration of Human Dermal Fibroblast in Diabetic Condition

A major symptom of diabetes mellitus (DM) is unfit hyperglycemia, which leads to impaired wound healing. It has been reported that the migration of fibroblasts can be suppressed under high glucose (HG) conditions. In our previous study, we introduced a serum-free culture method for mononuclear cells (MNCs) called quantity and quality control culture (QQc), which could improve the vasculogenic and tissue regeneration ability of MNCs. In this study, we described a culture model in which we applied a high glucose condition in human dermal fibroblasts to simulate the hyperglycemia condition in diabetic patients. MNC-QQ cells were cocultured with fibroblasts in this model to evaluate its role in improving fibroblasts dysfunction induced by HG and investigate its molecular mechanism. It was proven in this study that the impaired migration of fibroblasts induced by high glucose could be remarkably enhanced by coculture with MNC-QQ cells. PDGF B is known to play important roles in fibroblasts migration. Quantitative PCR revealed that MNC-QQ cells enhanced the gene expressions of PDGF B in fibroblasts under HG. Taken with these results, our data suggested a possibility that MNC-QQ cells accelerate wound healing via improving the fibroblasts migration and promote the gene expressions of PDGF B under diabetic conditions.

Mortality and Conversion Rates to Below-Knee or Above-Knee Amputation After Transmetatarsal Amputation

INTRODUCTION

The purpose of this study was to identify associated risk factors for complications, need for a higher level of amputation such as below-knee amputation (BKA) or above-knee amputation (AKA), and mortality after transmetatarsal amputation (TMA).

METHODS

We identified 265 patients who underwent 286 TMA procedures between June 2002 and July 2016. Medical records were reviewed for revision surgery and amputation. Mortality was verified using the National Death Index. We identified and documented potential risk factors including diabetes, hemoglobin A1c level, end-stage renal disease, cardiovascular disease, peripheral vascular disease, history of revascularization, contralateral amputation, and neuropathy. Sixty-eight percent were male, the mean age was 56.9 years (SD 12.8; range 24.1 to 92.1), and the median body mass index was 28.6 (interquartile range, 24.5 to 33.1).

RESULTS

Twenty-seven percent of the patients required a subsequent BKA or AKA after the index TMA surgery. The results of a multivariable model indicated that women (odds ratio [OR], 3.63; 95% confidence interval [CI], 1.716 to 7.672), patients aged 57 to 64 years (OR, 0.17; 95% CI, 0.06 to 0.51), and patients with a history of revascularization (OR, 7.06, 95% CI, 2.86 to 17.44) had markedly higher odds than the relevant comparison groups. Forty percent of the patients died after the index TMA at a median of 27 months. After adjusting for all patient factors, history of end-stage renal disease (OR, 2.2; 95% CI, 1.206 to 4.014) and cardiovascular disease (OR, 2.879; 95% CI, 1.615 to 5.131) remained markedly associated with mortality after TMA.

DISCUSSION

There are high rates of additional amputation after nontraumatic TMA and a high mortality rate. Surgeons should set realistic expectations with patients considered for TMA and identify risk factors, which may guide treatment. Treatment is multidisciplinary, requiring attention to surgical details, correction of vascular deficiency or contracture when present, and perioperative medical optimization.

LEVEL OF EVIDENCE

IV.

Phase I/IIa Feasibility Trial of Autologous Quality- and Quantity-Cultured Peripheral Blood Mononuclear Cell Therapy for Non-Healing Extremity Ulcers

Non-healing wounds are among the main causes of morbidity and mortality. We recently described a novel, serum-free ex vivo expansion system, the quantity and quality culture system (QQc), which uses peripheral blood mononuclear cells (PBMNCs) for effective and noninvasive regeneration of tissue and vasculature in murine and porcine models. In this prospective clinical study, we investigated the safety and efficacy of QQ-cultured peripheral blood mononuclear cell (MNC-QQ) therapy for chronic non-healing ischemic extremity wounds. Peripheral blood was collected from 9 patients with 10 chronic (>1 month) non-healing wounds (8 males, 1 female; 64-74 years) corresponding to ischemic extremity ulcers. PBMNCs were isolated and cultured using QQc. Within a 20-cm area surrounding the ulcer, 2 × 107 cells were injected under local anesthesia. Wound healing was monitored photometrically every 2 weeks. The primary endpoint was safety, whereas the secondary endpoint was efficacy at 12-week post-injection. All patients remained ambulant, and no deaths, other serious adverse events, or major amputations were observed for 12 weeks after cell transplantation. Six of the 10 cases showed complete wound closure with an average wound closure rate of 73.2% ± 40.1% at 12 weeks. MNC-QQ therapy increased vascular perfusion, skin perfusion pressure, and decreased pain intensity in all patients. These results indicate the feasibility and safety of MNC-QQ therapy in patients with chronic non-healing ischemic extremity wounds. As the therapy involves transplanting highly vasculogenic cells obtained from a small blood sample, it may be an effective and highly vasculogenic strategy for limb salvage.

Gender Differences in the Risk of Adverse Outcomes After Incident Diabetic Foot Hospitalization: A Population Cohort Study

BACKGROUND

Diabetic Foot Disease (DFD) is more prevalent among males and is associated with an excess risk of cardiovascular events or mortality.

AIMS

This study aimed at exploring the risk of cardiovascular events, renal failure, and all-cause mortality after incident DFD hospitalizations, separately in males and females, to detect any gender difference in a cohort of 322,140 people with diabetes retrospectively followed up through administrative data sources in Tuscany, Italy, over the years 2011-2018.

METHODS

The Hazard Ratio (HR) for incident adverse outcomes after first hospitalizations for DFD, categorized as major/minor amputations (No.=449;3.89%), lower limbs' revascularizations (LLR: No.=2854;24.75%), and lower-extremity-arterial-disease (LEAD) with no procedures (LEAD-no proc: No.=6282;54.49%), was compared to the risk of patients having a background of DFD (ulcers, infections, Charcot-neuroarthropathy: No.=1,944;16.86%).

RESULTS

DFD incidence rate was higher among males compared to females (1.57(95% CI:1.54-1.61) vs. 0.97(0.94-1.00)/100,000p-years]. After DFD, the overall risk of coronary artery disease was significantly associated with the male gender and of stroke with the female gender. LEAD-no proc and LLR were associated with the risk of stroke only in females, whereas they were found to be associated with the risk of coronary artery disease among females to a significantly greater extent compared to males. The incident of renal failure was not associated with any DFD category. Amputations and LEAD-no proc significantly predicted high mortality risk only in females, while LLR showed reduced risk in both genders. Moreover, females had a greater risk of composite outcomes (death or cardiovascular events). Compared to the background of DFD, the risk was found to be 34% higher after amputations (HR: 1.34(1.04-1.72)) and 10% higher after LEAD-no proc (HR:1.10(1.03-1.18)), confirming that after incident DFD associated with vascular pathogenesis, females are at an increased risk of adverse events.

CONCLUSION

After incident DFD hospitalizations, females with DFD associated with amputations or arterial disease are at a greater risk of subsequent adverse cardiovascular events than those with a DFD background.

Survival of Patients Following First Diagnosis of Diabetic Foot Complications: A Nationwide 15-Year Longitudinal Analysis

Background and Aims

The long-term survival in people with type 2 diabetes following first diagnosis of diabetic foot complications (FDDFC) is unclear. The object is to evaluate the mortality rate in subjects with type 2 diabetes following FDDFC and the impacts of the major cardiovascular comorbidities.

Methods

Nationwide data were analyzed for subjects with T2D and DFC between 2003 and 2017 according to ICD-9 coding. DFC was defined with the codes of ulcers, infections, or severe peripheral artery disease that required intervention (PAD) to mimic the real world diagnosis. Criteria of FDDFC were preceded by a period without any DFC for at least 5 years. Major cardiovascular comorbidities: established PAD and cardiovascular diseases (CVD: including coronary heart disease (CHD), stroke, or heart failure) before the index date as well as lower-extremity amputations (LEA) at the index episode were analyzed.

Results

Among 300,115 subjects with DFC, a total of 103,396 patients had FDDFC. The mean 5-year survival rate of these subjects was 81.05%. Using subjects without associated major cardiovascular comorbidity as baseline, the adjusted hazard ratios (aHR) were1.43 (95% confidence interval 1.38-1.49) in group PAD-/CVD+, followed by 1.70 (1.59-1.80) in PAD+/CVD- and 1.98 (1.89-2.08) in PAD+/CVD+. The aHR was further increased in patients with PAD who additionally had heart failure (3.77, 3.50-4.05), stroke (2.06, 1.95-2.18), or CHD (1.89, 1.79-2.00). Subjects with PAD rather than other CVD were associated with LEA at FDDFC. Patients with major LEA (above the ankle) at FDDFC episode had lower 5-year survival rate (65.01%) followed by those with minor LEA (72.24%) and without LEA (81.61%).

Conclusions

Cardiovascular comorbidity as well as LEA status at the event of FDDFCs were both associated with patient survival outcomes. Earlier identification of this large population could lead to higher survival rates.

Fetal bovine acellular dermal matrix for the closure of diabetic foot ulcers: a prospective randomised controlled trial

AIM

The purpose of this clinical trial was to evaluate the safety and efficacy of a fetal bovine acellular dermal matrix (FBADM) plus standard of care (SOC) for treating hard-to-heal diabetic foot ulcers (DFUs).

METHOD

A prospective, multi-centre, randomised controlled trial was carried out. The study included a 2-week run-in period, a 12-week treatment phase and a 4-week follow-up phase. The primary endpoint was complete wound closure at 12 weeks.

RESULTS

Twenty-one US sites enrolled and randomised 226 patients with hard-to-heal DFUs. The study was terminated early due to the COVID-19 pandemic, which led to a modified intent-to-treat (mITT) population of 207 patients, with 103 in the FBADM group and 104 in the SOC group. Of these participants, 161 completed the study per protocol (mPP population), with 79 receiving FBADM, and 82 without. At the first analysis point, patients treated with FBADM were found to be significantly more likely to achieve complete wound closure compared with SOC alone (mITT: 45.6% versus 27.9% p=0.008; mPP: 59.5% versus 35.6% p=0.002). The difference in outcome yielded an odds ratio of 2.2 (95% confidence interval (CI): 1.2, 3.9; p=0.008). Median time to closure within 12 weeks was 43 days for the FBADM group compared to 57 days for the SOC group (p=0.36). The median number of applications of FBADM to achieve closure was one. Adverse events were similar between groups and no product-related serious adverse events occurred.

CONCLUSIONS

These results indicate that in many cases a single application of FBADM in conjunction with SOC offers a safe, faster and more effective treatment of DFUs than SOC alone.

Common late complications of longitudinal forefoot amputations in neuropathic foot treatment

OBJECTIVE

To describe and quantify the complications arising in consecutive neuropathic patients undergoing partial longitudinal amputations of the foot.

METHOD

A retrospective study was conducted with data collected from the medical records of patients monitored at the Insensitive Foot Clinic of the Foot and Ankle Group of our institution who underwent partial amputation of foot rays from 2000 to 2016.

RESULTS

A total of 28 patients met the inclusion criteria, with a total of 31 amputated/partially amputated feet. Of these, 18 (58.1%) feet were amputated/partially amputated due to diabetes, seven (22.6%) due to leprosy, two (6.5%) due to alcoholic neuropathy, two (6.5%) secondary to traumatic peripheral nerve injury, and two (6.5%) due to other causes. Fifth ray amputation was the most frequent type (n=12). The cause of amputation was the presence of an infected ulcer in 93.6% of the samples. At a mean follow-up time of 60 months, 13 (41.9%) feet required new amputations-five (38.5%) transtibial, five (38.5%) transmetatarsal, two (15.4%) of the toes, and one (7.7%) at Chopart's joint. Patients with diabetes had a 50.0% reamputation rate. Patients who initially underwent amputation of the fifth ray had a 58.3% reamputation rate.

CONCLUSION

Partial longitudinal amputation of the foot in neuropathic patients exhibited a high reoperation rate, especially in patients with diabetes or in patients with initial amputation of the peripheral rays. Declaration of interest: The authors have no conflicts of interest.

Long-term Mortality After Nontraumatic Major Lower Extremity Amputation: A Systematic Review and Meta-analysis

Chronic wounds that lead to major lower extremity amputation have immense consequences on quality of life, and ultimately, mortality. However, mortality rates after lower extremity amputation for a chronic wound are broad within the literature and have escaped precise definition. This systematic review aims to quantify long-term mortality rates after major lower extremity amputation in the chronic wound population available in the existing literature. Ovid MEDLINE was searched for publications which provided mortality data after major, nontraumatic, primary lower extremity amputations. Lower extremity amputations were defined as below and above the knee amputation. Data from included studies was analyzed to obtain pooled 1-, 2-, 3-, 5- and 10-year mortality rates. Sixty-one studies satisfied inclusion criteria representing 36,037 patients who underwent nontraumatic major lower extremity amputation. Pooled mortality rates were 33.7%, 51.5%, 53%, 64.4%, and 80% at 1-, 2-, 3-, 5- and 10-year follow-up, respectively. Within the 8184 diabetic patients (types 1 and 2), 1- and 5-year mortality was 27.3% and 63.2%. Sources of mortality data were varied and included electronic medical records, national health and insurance registries, and government databases. Mortality after nontraumatic major lower extremity amputation is high, both in patients with diabetes as well as those without. Methods used to measure and report mortality are inconsistent, lack reliability, and may underestimate true mortality rates. These findings illustrate the need for a paradigm shift in wound management and improved outcomes reporting. A focus on amputation prevention and care within a multidisciplinary team is critical for recalcitrant ulcers.

Effectiveness, Safety, and Acceptance of an Interim Orthosis in Patients with Diabetes in the Immediate Postoperative Chopart Surgery

Chopart amputation is the consequence of severe diabetes-related foot complications. A new interim orthosis allowing the patient a greater degree of mobility after Chopart surgery than currently used systems is now available. The aim of this study was to evaluate the effectiveness of the new orthosis compared with traditional treatment. Safety and level of patient acceptance of the device were also investigated. We performed a retrospective case-control observational study involving people with diabetes who underwent Chopart amputation between January 2016 and January 2018. The sample of subjects treated with the innovative orthosis was compared with consecutive patients, who were treated with traditional management. The main study outcomes include major amputation occurrence, ulcer recurrence, healing time, and patient acceptance of the orthosis. Patient satisfaction was evaluated using the Italian validated version of the Orthotic Prosthetic User's Survey (OPUS) questionnaire. Overall, 27 subjects were enrolled using the new device (mean age 68.7 ± 8.4 years, 70.4% males, mean diabetes duration 22.7 ± 15 years). Clinical baseline characteristics were comparable between the cases and the controls. There was no difference between the groups in the healed wound rate (81.5% vs 80.0% for cases and the control group, respectively, P = .53). The ulcer recurrence rate was higher in the control group compared with subjects using the new orthosis (62.5% vs 24.0%, respectively, P = .04). The use of the innovative orthosis was associated with an 81% lower probability to have ulcer recurrence (odds ratio 0.19, 95% confidence interval 0.04-1.04). No between groups difference was detected for a major amputation rate. The wound healing time was faster for cases compared with controls (160.4 ± 114.1 vs 256.5 ± 112.9 days, P = .05). No adverse events related to the use of the new orthosis were recorded. Patient acceptance of the new orthosis was high. This orthosis can be recommended as an efficient, safe, and well-accepted device after Chopart amputation.

Transmetatarsal and Minor Amputation Versus Major Leg Amputation: 30-Day Readmissions, Reamputations, and Complications

AIMS

The optimal level of lower-extremity amputation, particularly in diabetic patients with ulceration, is debated. Proximal amputations more greatly decrease function versus distal amputations, but healing and complication rates may differ between the 2 types. This study compares early postoperative outcomes after transmetatarsal and other partial foot amputations and major leg amputations.

METHODS

Data were derived from National Surgical Quality Improvement Program datasets covering 2012 to 2014. Outcomes studied include 30-day rates of readmission to hospital for wound complications. We matched the 2 types of amputation patients by propensity score to fairly compare between levels of amputation when either type of amputation might be indicated. The same analysis was then performed with emphasis on diabetic patients.

RESULTS

Major amputation patients were more likely to have dependent functional status, although their surgeries tended to be more complicated. Minor amputation patients had 2.5 times the odds of irrigation and debridement compared with major amputation patients, but only 0.49 and 0.47 times the odds of urinary tract infection or transfusion, respectively.

CONCLUSIONS

Although short-term complications, readmissions, and reoperations were more common in distal amputation, UTI and the need for transfusion were higher in major amputation.

Reconstructive Amputations of the Foot

In the diabetic and peripheral vascular disease population there is a high risk of further amputation following a primary amputation. Amputation surgery is often approached negating the biomechanics of the lower extremity leading to complications or additional surgery. Implementing appropriate tendon balancing of stump and applying orthoplastic techniques will improve outcomes. This article introduces the basic techniques to a wider audience of foot and ankle surgeons. Specifically, this article is intended to be a descriptive guide for the use of tendon balancing and intrinsic muscle advancements in the various levels of foot amputations.

An economic evaluation examining the cost-effectiveness of continuous diffusion of oxygen therapy for individuals with diabetic foot ulcers

Continuous delivery of oxygen therapy has been observed to improve healing for individuals with an advanced diabetic foot ulcer (DFU). However, this intervention requires the purchasing of an oxygen delivery device and moist dressings. It is unknown whether this upfront financial investment represents good value for money. Thus the aim of this project is to evaluate the cost-effectiveness of treating advanced DFU using continuous delivery of oxygen compared with negative pressure wound therapy from the perspective of the public health care payer in Ontario, Canada. A microsimulation model was constructed with inputs from peer-reviewed journal publications and publicly available reports. The 5-year costs and quality-adjusted life-years were compared between treatment and comparator. Sensitivity analyses were conducted to evaluate the robustness of results. The model predicted that continuous delivery of oxygen would cost $4800 less compared with negative pressure wound therapy and increased quality-adjusted life years by 0.025. Lower cost and improved outcomes were observed in most scenario analyses. The results of this economic evaluation suggest that CDO therapy may reduce health care economic burden with a modest increase in quality of life outcomes. Health care decision-makers should consider the inclusion of CDO for the treatment of DFU.

Five year mortality and direct costs of care for people with diabetic foot complications are comparable to cancer

BACKGROUND

In 2007, we reported a summary of data comparing diabetic foot complications to cancer. The purpose of this brief report was to refresh this with the best available data as they currently exist. Since that time, more reports have emerged both on cancer mortality and mortality associated with diabetic foot ulcer (DFU), Charcot arthropathy, and diabetes-associated lower extremity amputation.

METHODS

We collected data reporting 5-year mortality from studies published following 2007 and calculated a pooled mean. We evaluated data from DFU, Charcot arthropathy and lower extremity amputation. We dichotomized high and low amputation as proximal and distal to the ankle, respectively. This was compared with cancer mortality as reported by the American Cancer Society and the National Cancer Institute.

RESULTS

Five year mortality for Charcot, DFU, minor and major amputations were 29.0, 30.5, 46.2 and 56.6%, respectively. This is compared to 9.0% for breast cancer and 80.0% for lung cancer. 5 year pooled mortality for all reported cancer was 31.0%. Direct costs of care for diabetes in general was $237 billion in 2017. This is compared to $80 billion for cancer in 2015. As up to one-third of the direct costs of care for diabetes may be attributed to the lower extremity, these are also readily comparable.

CONCLUSION

Diabetic lower extremity complications remain enormously burdensome. Most notably, DFU and LEA appear to be more than just a marker of poor health. They are independent risk factors associated with premature death. While advances continue to improve outcomes of care for people with DFU and amputation, efforts should be directed at primary prevention as well as those for patients in diabetic foot ulcer remission to maximize ulcer-free, hospital-free and activity-rich days.

Epigenetic Regulation of TLR4 in Diabetic Macrophages Modulates Immunometabolism and Wound Repair

Macrophages are critical for the initiation and resolution of the inflammatory phase of wound healing. In diabetes, macrophages display a prolonged inflammatory phenotype preventing tissue repair. TLRs, particularly TLR4, have been shown to regulate myeloid-mediated inflammation in wounds. We examined macrophages isolated from wounds of patients afflicted with diabetes and healthy controls as well as a murine diabetic model demonstrating dynamic expression of TLR4 results in altered metabolic pathways in diabetic macrophages. Further, using a myeloid-specific mixed-lineage leukemia 1 (MLL1) knockout (Mll1^f/fLyz2^Cre+ ), we determined that MLL1 drives Tlr4 expression in diabetic macrophages by regulating levels of histone H3 lysine 4 trimethylation on the Tlr4 promoter. Mechanistically, MLL1-mediated epigenetic alterations influence diabetic macrophage responsiveness to TLR4 stimulation and inhibit tissue repair. Pharmacological inhibition of the TLR4 pathway using a small molecule inhibitor (TAK-242) as well as genetic depletion of either Tlr4 (Tlr4^-/- ) or myeloid-specific Tlr4 (Tlr4^f/fLyz2^Cre+) resulted in improved diabetic wound healing. These results define an important role for MLL1-mediated epigenetic regulation of TLR4 in pathologic diabetic wound repair and suggest a target for therapeutic manipulation.

Mortality, Reamputation, and Preoperative Comorbidities in Patients Undergoing Dysvascular Lower Limb Amputation

BACKGROUND

Historically, mortality rates after major lower limb amputations (LLAs) have been very high. However, there are inconsistencies regarding the risk factors. The reamputation rate after major LLAs is largely unknown. The aim of this study is to report the 30-day and 1-year mortality and 1-year reamputation rates after major LLA and to identify potential risk factors.

METHODS

An observational cohort study in which all patients undergoing dysvascular major LLA in 2012-2013 in 12 hospitals in the northern region of the Netherlands is included.

RESULTS

Of total 382 patients, who underwent major LLA, 65% were male and the mean age (standard deviation [SD]) was 71.9 ± 12.5 years. Peripheral arterial disease was observed in 88% and diabetes mellitus (DM), in 56% of patients. No revascularization or prior LLA on the amputated side was observed among 26%, whereas 56% had no minor or major LLA on either limb before the study period. The 30-day and 1-year mortality rates were 14% and 34%, respectively. Patients aged 75-84 and >85 years had 3-4 times higher odds of dying within 1 year. Transfemoral amputations (odds ratio [OR], 2.2), history of heart failure (OR, 2.3), myocardial infarction (OR, 1.7), hemodialysis (OR, 5.7), immunosuppressive medication (OR, 2.8), and guillotine amputations (OR, 5.1) were independently associated with 1-year mortality. Twenty-six percent underwent ipsilateral reamputation within 1 year, for which no risk factors were identified.

CONCLUSIONS

The mortality rate in the first year after major LLA is high, particularly among those undergoing transfemoral amputations, which is likely to be indicative of more severe vascular disease. Higher mortality among the most elderly patients, those with more severe cardiac disease and who underwent hemodialysis reflects the frailty of this population. Interestingly, DM, revascularization history, and prior minor or major LLA were not associated with mortality rates.

Time Trends in the Incidence of Long-Term Mortality in T2DM Patients Who Have Undergone a Lower Extremity Amputation. Results of a Descriptive and Retrospective Cohort Study

(1) Background: The aims of this study were to examine the incidence of lower extremity amputations (LEAs) among patients with type 2 diabetes mellitus (T2DM) and to compare the mortality risk of diabetic individuals who underwent LEA with age and sex-matched diabetic individuals without LEA. (2) Methods: We performed a descriptive observational study to assess the trend in the incidence of LEA and a retrospective cohort study to evaluate whether undergoing LEA is a risk factor for long-term mortality among T2DM patients. Data were obtained from the Hospital Discharge Database for the Autonomous Community of Madrid, Spain (2006–2015). (3) Results: The incidence rates of major below-knee and above-knee amputations decreased significantly from 24.9 to 17.1 and from 63.9 to 48.2 per 100000 T2DM individuals from 2006 to 2015, respectively. However, the incidence of minor LEAs increased over time. Mortality was significantly higher among T2DM patients who underwent LEA compared with those who did not undergo this procedure (HR 1.75; 95% CI 1.65–1.87). Male sex, older age, and comorbidity were independently associated with higher mortality after LEA. (4) Conclusions: Undergoing a LEA is a significant risk factor for long term mortality among T2DM patients, and those who underwent a major above-knee LEAs have the highest risk.

Influence of Microbiota on Diabetic Foot Wound in Comparison with Adjacent Normal Skin Based on the Clinical Features

Diabetic foot ulcer (DFU) is a complication experienced by diabetic patients and does not heal well in an altered wound environment. Although diverse microbes in DFU were detected, little is known about their influences on diabetic foot wound (DFW) and the association with the skin microbiota in normal tissue from the same patients according to clinical features. We aimed to analyze the microbiota in normal skin and DFW tissue from the same subject and predict their roles based on clinical features. We analyzed the microbiota in normal skin and DFW tissue from the same subject and compared the associated members of microbiota with clinical parameters. The diversity of skin microbiota was higher than that of DFW tissues, along with compositional differences. In addition, different microbes were associated with clinical features. The proportions of Bacteroidetes, Prevotella, Peptoniphilus, Porphyromonas, and Dialister were higher in the severe groups than of the mild groups, whereas that of Firmicutes was lower in the severe groups. According to wound severity, the microbiota could be related to inflammation, damaging host cell membrane, and pathogenicity through lipopolysaccharide biosynthesis, cellular antigens, and protein digestion metabolism. The predicted DFW microbiota functions according to systemic diabetic status defined by ESRD and HbA1c, differed from those presented by wound severity. Results indicate that the microbiota in normal skin is related to the colonizing microbes in DFW tissue according to clinical features and the different microbes can play important roles in DFW prognosis. This information can be applied to prevent and manage DFW by modulating the microbiota.

The Histone Methyltransferase Setdb2 Modulates Macrophage Phenotype and Uric Acid Production in Diabetic Wound Repair

Macrophage plasticity is critical for normal tissue repair to ensure transition from the inflammatory to the proliferative phase of healing. We examined macrophages isolated from wounds of patients afflicted with diabetes and of healthy controls and found differential expression of the methyltransferase Setdb2. Myeloid-specific deletion of Setdb2 impaired the transition of macrophages from an inflammatory phenotype to a reparative one in normal wound healing. Mechanistically, Setdb2 trimethylated histone 3 at NF-κB binding sites on inflammatory cytokine gene promoters to suppress transcription. Setdb2 expression in wound macrophages was regulated by interferon (IFN) β, and under diabetic conditions, this IFNβ-Setdb2 axis was impaired, leading to a persistent inflammatory macrophage phenotype in diabetic wounds. Setdb2 regulated the expression of xanthine oxidase and thereby the uric acid (UA) pathway of purine catabolism in macrophages, and pharmacologic targeting of Setdb2 or the UA pathway improved healing. Thus, Setdb2 regulates macrophage plasticity during normal and pathologic wound repair and is a target for therapeutic manipulation.

Increased mortality among patients with diabetes following first-ever transfemoral amputation

AIMS

Transfemoral amputation (TFA) is associated with a high postoperative mortality though it is unclear whether diabetes is associated with an increased mortality or not. The aim was to examine mortality at 1 week and 1 year after first-ever TFA with special reference to diabetes.

METHODS

We included 162 first-ever TFAs from 1996 to 2012. Mortality data were collected with the use of the Swedish personal identification number.

RESULTS

The median age was 85 years. Diabetes mellitus were present in 19% (n = 30) of the patients and 67% (n = 109) had cardiovascular disease. Mortality was significantly higher for patients with diabetes compared to patients without diabetes at 1 week (30% vs. 8%, p = 0.001) and at 1 year (80% vs. 57%, p = 0.02). This difference was significant in multivariable analysis.

CONCLUSIONS

We conclude that postoperative mortality was high. The high mortality rate emphasizes the need for early and adequate evaluation of every patient́s overall condition and whether amputation is beneficial or not. Although further studies are needed to analyze the specific causes of early death in amputees and we suggest close monitoring of blood-sugar in patients with diabetes and early treatment of infections and cardiac events in all patients.

Acceleration of Diabetic Wound Healing with PHD2- and miR-210-Targeting Oligonucleotides

In diabetes-associated chronic wounds, the normal response to hypoxia is impaired and many cellular processes involved in wound healing are hindered. Central to the hypoxia response is hypoxia-inducible factor-1α (HIF-1α), which activates multiple factors that enhance wound healing by promoting cellular motility and proliferation, new vessel formation, and re-epithelialization. Prolyl hydroxylase domain-containing protein 2 (PHD2) regulates HIF-1α activity by targeting it for degradation under normoxia. HIF-1α also upregulates microRNA miR-210, which in turn regulates proteins involved in cell cycle control, DNA repair, and mitochondrial respiration in ways that are antagonistic to wound repair. We have identified a highly potent short synthetic hairpin RNA (sshRNA) that inhibits expression of PHD2 and an antisense oligonucleotide (antimiR) that inhibits miR-210. Both oligonucleotides were chemically modified for improved biostability and to mitigate potential immunostimulatory effects. Using the sshRNA to silence PHD2 transcripts stabilizes HIF-1α and, in combination with the antimiR targeting miR-210, increases proliferation and migration of keratinocytes in vitro. To assess activity and delivery in an impaired wound healing model in diabetic mice, PHD2-targeting sshRNAs and miR-210 antimiRs both alone and in combination were formulated for local delivery to wounds using layer-by-layer (LbL) technology. LbL nanofabrication was applied to incorporate sshRNA into a thin polymer coating on a Tegaderm mesh. This coating gradually degrades under physiological conditions, releasing sshRNA and antimiR for sustained cellular uptake. Formulated treatments were applied directly to splinted full-thickness excisional wounds in db/db mice. Cellular uptake was confirmed using fluorescent sshRNA. Wounds treated with a single application of PHD2 sshRNA or antimiR-210 closed 4 days faster than untreated wounds, and wounds treated with both oligonucleotides closed on average 4.75 days faster. Markers for neovascularization and cell proliferation (CD31 and Ki67, respectively) were increased in the wound area following treatment, and vascular endothelial growth factor (VEGF) was increased in sshRNA-treated wounds. Our results suggest that silencing of PHD2 and miR-210 either together or separately by localized delivery of sshRNAs and antimiRs is a promising approach for the treatment of chronic wounds, with the potential for rapid clinical translation.

Therapeutic Apheresis in Metabolic Syndrome

BACKGROUND

The metabolic syndrome unites three pathologies of the person - obesity, arterial hypertension and diabetes. In recent years the progressing of such distribution covering from 2.5% to 3.8% of the population with increase twice each 10-15 years is noted. Even at maintenance of level of sugar at diabetes accumulation of the secondary metabolites breaking small vessels isn't excluded. At the same time many life-endangering complications develop.

OBJECTIVE

To identify the possibilities of plasmapheresis in the prevention and treatment of complications of metabolic syndrome.

METHOD

Analysis of the world literature data on complications of metabolic syndrome and methods of their treatment.

RESULTS

At metabolic syndrome the frequency of strokes and myocardial infarctions there is twice more often than in population. For 5-9 years the general life expectancy decreases. Disorders of microcirculation at diabetes lead to a retinopathy with total loss of sight, a nephropathy from the outcome in a renal failure, to polyneuropathy and diabetic foot syndrome with high risk of high level amputations of the lower extremities. At the same time medicamentous therapy is not able to prevent such complications and almost only way of removal of these pathological metabolites is therapeutic apheresis, mainly the plasmapheresis. Data from our own studies confirm the effectiveness of such tactics.

CONCLUSION

Plasmapheresis has to be applied not only to the correction of already critical conditions, but also to their prevention.

Survival and associated risk factors in patients with diabetes and amputations caused by infectious foot gangrene

Background

Infectious gangrene of the foot is a serious complication of diabetes that usually leads to a certain level of lower-extremity amputation (LEA). Nevertheless, the long-term survival and factors associated with mortality in such patients have yet to be elucidated.

Methods

A total of 157 patients with type 2 diabetes who received treatment for infectious foot gangrene at a major diabetic foot center in Taiwan from 2002 to 2009 were enrolled, of whom 90 had major LEAs (above the ankle) and 67 had minor LEAs (below the ankle). Clinical data during treatment were used for the analysis of survival and LEA, and survival was tracked after treatment until December 2012.

Results

Of the 157 patients, 109 died, with a median survival time of 3.12 years and 5-year survival rate of 40%. Age [hazard ratio 1.04 (95% confidence interval 1.01–1.06)], and major LEA [1.80 (1.05–3.09)] were independent factors associated with mortality. Patients with minor LEAs had a better median survival than those with major LEAs (5.5 and 1.9 years, respectively, P < 0.01). An abnormal ankle-brachial index was an independent risk factor [odds ratio 3.12 (95% CI 1.18–8.24)] for a poor outcome (major LEA) after adjusting for age, smoking status, hypertension, major adverse cardiac events, and renal function.

Conclusions

Efforts to limit amputations below the ankle resulted in better survival of patients with infectious foot gangrene. An abnormal ankle-brachial index may guide physicians to make appropriate decisions with regards to the amputation level.

The Histone Methyltransferase MLL1 Directs Macrophage-Mediated Inflammation in Wound Healing and Is Altered in a Murine Model of Obesity and Type 2 Diabetes

Macrophages are critical for the initiation and resolution of the inflammatory phase of wound repair. In diabetes, macrophages display a prolonged inflammatory phenotype in late wound healing. Mixed-lineage leukemia-1 (MLL1) has been shown to direct gene expression by regulating nuclear factor-κB (NF-κB)-mediated inflammatory gene transcription. Thus, we hypothesized that MLL1 influences macrophage-mediated inflammation in wound repair. We used a myeloid-specific Mll1 knockout (Mll1^f/fLyz2^Cre+ ) to determine the function of MLL1 in wound healing. Mll1^f/fLyz2^Cre+ mice display delayed wound healing and decreased wound macrophage inflammatory cytokine production compared with control animals. Furthermore, wound macrophages from Mll1^f/fLyz2^Cre+ mice demonstrated decreased histone H3 lysine 4 trimethylation (H3K4me3) (activation mark) at NF-κB binding sites on inflammatory gene promoters. Of note, early wound macrophages from prediabetic mice displayed similarly decreased MLL1, H3K4me3 at inflammatory gene promoters, and inflammatory cytokines compared with controls. Late wound macrophages from prediabetic mice demonstrated an increase in MLL1, H3K4me3 at inflammatory gene promoters, and inflammatory cytokines. Prediabetic macrophages treated with an MLL1 inhibitor demonstrated reduced inflammation. Finally, monocytes from patients with type 2 diabetes had increased Mll1 compared with control subjects without diabetes. These results define an important role for MLL1 in regulating macrophage-mediated inflammation in wound repair and identify a potential target for the treatment of chronic inflammation in diabetic wounds.

While Mortality Rates Differ After Dysvascular Partial Foot and Transtibial Amputation, Should They Influence the Choice of Amputation Level?

Although there is strong evidence to show that the risk of dying after transtibial amputation is higher than partial foot amputation, we are concerned by the implication that amputation level influences mortality, and that such interpretations of the evidence may be used to inform decisions about the choice of amputation level. We argue that the choice of partial foot or transtibial amputation does not influence the risk of mortality. The highest mortality rates are observed in studies with older people with more advanced systemic disease and multiple comorbidities. Studies that control for the confounding influence of these factors have shown no differences in mortality rates by amputation level. These insights have important implications in terms of how we help inform difficult decisions about amputation at either the partial foot or transtibial level, given a more thoughtful interpretation of the published mortality rates.

Influence of Epidemiologic and Patient Behavior–Related Predictors on Amputation Rates in Diabetic Patients

Amputation of patients with diabetic foot is a major issue worldwide, particularly from a medical and economic standpoint. This meta-analysis aimed to identify significant risk factors of high amputation rate among epidemiologic and patient behavior–related predictors in diabetic patients. A systematic literature review and meta-analysis were performed using MEDLINE, EMBASE, and Cochrane databases. Seven variables were extracted from the included studies and evaluated based on amputation rate. The Newcastle-Ottawa scale was used to assess the quality of the studies. The search strategy identified 101 publications. After screening, 33 articles were selected for review. Male sex and smoking were identified as significant risk factors of high amputation rate of diabetic foot. Although further investigation of long-term and randomized controlled studies is needed, we identified 2 variables as significant risk factors for high amputation rate in diabetic patients in this meta-analysis.

Outcomes of dysvascular partial foot amputation and how these compare to transtibial amputation: a systematic review for the development of shared decision-making resources

BACKGROUND

Dysvascular partial foot amputation (PFA) is a common sequel to advanced peripheral vascular disease. Helping inform difficult discussions between patients and practitioners about the level of PFA, or the decision to have a transtibial amputation (TTA) as an alternative, requires an understanding of the current research evidence on a wide range of topics including wound healing, reamputation, quality of life, mobility, functional ability, participation, pain and psychosocial outcomes, and mortality. The aim of this review was to describe a comprehensive range of outcomes of dysvascular PFA and compare these between levels of PFA and TTA.

METHODS

The review protocol was registered in PROSPERO (CRD42015029186). A systematic search of the literature was conducted using MEDLINE, EMBASE, psychINFO, AMED, CINAHL, ProQuest Nursing and Allied Health, and Web of Science. These databases were searched using MeSH terms and keywords relating to different amputation levels and outcomes of interest. Peer reviewed studies of original research-irrespective of the study design-were included if published in English between 1 January 2000, and 31 December 2015, and included discrete cohort(s) with dysvascular PFA or PFA and TTA. Outcomes of interest were rate of wound healing and complications, rate of ipsilateral reamputation, quality of life, functional ability, mobility, pain (i.e., residual limb or phantom pain), psychosocial outcomes (i.e., depression, anxiety, body image and self-esteem), participation, and mortality rate. Included studies were independently appraised by two reviewers. The McMaster Critical Review Forms were used to assess methodological quality and identify sources of bias. Data were extracted based on the Cochrane Consumers and Communication Review Group's data extraction template by a primary reviewer and checked for accuracy and clarity by a second reviewer. Findings are reported as narrative summaries given the heterogeneity of the literature, except for mortality and ipsilateral reamputation where data allowed for proportional meta-analyses.

RESULTS

Twenty-nine unique articles were included in the review, acknowledging that some studies reported multiple outcomes. Eighteen studies reported all-cause proportionate mortality. A smaller number of studies reported outcomes related to functional ability (two), mobility (four), quality of life (three), ipsilateral reamputation (six) as well as wound healing and complications (four). No studies related to pain, participation or psychosocial outcomes met the inclusion criteria. Subjects were typically older and male and had diabetes among other comorbidities. More detailed information about the cohorts such as race or sociodemographic factors were reported in an ad hoc manner. Common sources of bias included contamination, co-intervention, or lack of operational definition for some outcomes (e.g., wound healing) as illustrative examples.

CONCLUSIONS

Aside from mortality, there was limited evidence regarding outcomes of dysvascular PFA, particularly how outcomes differ between levels of PFA and TTA. Acknowledging that there is considerable uncertainty given the small body of literature on many topics where the risk of bias is high, the available evidence suggests that a large proportion of people with PFA experience delayed wound healing and ipsilateral reamputation. People with TTA have increased risk of mortality compared to those with PFA, which may reflect that those considered suitable candidates for TTA have more advanced systemic disease that also increases the risk of dying. Mobility and quality of life may be similar in people with PFA and TTA.

SYSTEMATIC REVIEW REGISTRATION

CRD42015029186.

The impact of gender, level of amputation and diabetes on prosthetic fit rates following major lower extremity amputation

BACKGROUND

Diabetes mellitus is a leading cause of major lower extremity amputation.

OBJECTIVE

To examine the influence of gender, level of amputation and diabetes mellitus status on being fit with a prosthetic limb following lower extremity amputation for peripheral arterial disease.

STUDY DESIGN

Retrospective analysis of the Scottish Physiotherapy Amputee Research Group dataset.

RESULTS

Within the cohort with peripheral arterial disease ( n = 1735), 64% were men ( n = 1112) and 48% ( n = 834) had diabetes mellitus. Those with diabetes mellitus were younger than those without: mean 67.5 and 71.1 years, respectively ( p < 0.001). Trans-tibial amputation:trans-femoral amputation ratio was 2.33 in those with diabetes mellitus, and 0.93 in those without. A total of 41% of those with diabetes mellitus were successfully fit with a prosthetic limb compared to 38% of those without diabetes mellitus. Male gender positively predicted fitting with a prosthetic limb at both trans-tibial amputation ( p = 0.001) and trans-femoral amputation ( p = 0.001) levels. Bilateral amputations and increasing age were negative predictors of fitting with a prosthetic limb ( p < 0.001). Diabetes mellitus negatively predicted fitting with a prosthetic limb at trans-femoral amputation level ( p < 0.001). Mortality was 17% for the cohort, 22% when the amputation was at trans-femoral amputation level.

CONCLUSION

Of those with lower extremity amputation as a result of peripheral arterial disease, those with diabetes mellitus were younger, and more had trans-tibial amputation. Although both age and amputation level are good predictors of fitting with a prosthetic limb, successful limb fit rates were no better than those without diabetes mellitus. Clinical relevance This is of clinical relevance to those who are involved in the decision-making process of prosthetic fitting following major amputation for dysvascular and diabetes aetiologies.

Effect of limb preservation status and body mass index on the survival of patients with limb-threatening diabetic foot ulcers

AIMS

To evaluate the effect of limb preservation status and body mass index (BMI) on the survival of patients with diabetic foot ulcers (DFUs).

METHODS

A total of 1346 patients treated for limb-threatening DFUs at a major diabetic foot center in Taiwan from 2002 to 2009 were tracked until December 2012. The patients were classified into three groups: limb-preserved (n=858), minor lower-extremity amputation (LEA) (n=249), and major LEA (n=239). Clinical data during treatment were used for survival analysis.

RESULTS

With 729 deaths, the median survival time (MST) was 6.14 (95% CI 5.63-6.65) years. Major LEA and BMI were two independent factors associated with mortality after adjusting for age, diabetic duration, HbA1c level, comorbidities and peripheral artery diseases. The mortality hazard ratios for the minor and major LEA groups were 0.92 (95% CI 0.74-1.16) and 1.34 (95% CI 1.07-1.68), respectively, to the reference group (limb-preserved). After stratifying BMI into four categories (underweight, normal weight, overweight and obesity, according to the Taiwanese definition), the MSTs for each category were 2.57, 5.24, 7.47 and 7.85years, respectively (P for trend <0.01). This "obesity paradox" was not observed in the major LEA group (P for trend 0.25). For patients with LEA, the obesity patients had lower MST than those in overweight category (7.97 and 8.84 in minor and 3.25 and 5.42 in major LEA, respectively).

CONCLUSIONS

For the patients treated for DFUs, major - but not minor - LEA was associated with poor survival compared with the limb-preserved group. The MST had positive correlation with BMI levels for patients with limb-preserved and minor LEA, but not for those with major LEA.

The Geriatric Nutritional Risk Index Independently Predicts Mortality in Diabetic Foot Ulcers Patients Undergoing Amputations

Objective. Patients with diabetic foot ulcers undergoing amputations have poor prognosis. Malnutrition usually occurs in this population and is associated with increased risk of mortality. The geriatric nutritional risk index (GNRI) is a widely used, simple, and well-established tool to assess nutritional risk. The purpose of this study was to assess the association between GNRI and all-cause mortality in diabetic foot ulcers patients undergoing minor or major amputations. Methods. This was a retrospective cohort study including 271 adult patients. Patients were divided into two groups according to a GNRI cutoff value of 92, and characteristics and mortality were compared between the two groups. Cox proportional hazard analysis was performed to explore the association between GNRI and mortality. Result. GNRI (p < 0.001), age (p < 0.001), and eGFR (p = 0.002) were independent predictors of mortality. Among a subgroup of 230 patients with minor amputation, increased age (p < 0.001), coronary artery disease (p = 0.030), and increased GNRI (p < 0.001) were major risk factors. Conclusion. GNRI on admission might be a novel clinical predictor for the incidence of death in patients with diabetic foot ulcers who were undergoing amputations.

Invasive Systemic Infection After Hospital Treatment for Diabetic Foot Ulcer: Risk of Occurrence and Effect on Survival

BACKGROUND

Diabetic foot ulcers (DFUs) threaten limbs and prompt hospitalization. After hospitalization, remote-site invasive systemic infection related to DFU (DFU-ISI) may occur. The characteristics of DFU-ISIs and their effect on mortality risk have not been defined.

METHODS

We conducted a retrospective cohort study of 819 diabetic patients hospitalized for treatment of 1212 unique DFUs during a 9-year period. We defined the index ulcer as that present at the first (index) DFU admission to our hospital. We defined DFU-ISI as a nonfoot infection that occurred after the index hospitalization and was caused by a microorganism concomitantly or previously cultured from the index ulcer. We determined the frequency, risk factors, and mortality risk associated with DFU-ISIs.

RESULTS

After 1212 index DFU hospitalizations, 141 patients had 172 DFU-ISIs. Of the initial 141 DFU-ISIs, 64% were bacteremia, 13% deep abscesses, 10% pneumonia, 7% endocarditis, and 6% skeletal infections. Methicillin-resistant Staphylococcus aureus (MRSA) caused 57% of the ISIs. Patients with initial DFU cultures yielding MRSA and protracted open ulcers had a high 24-month cumulative probability of DFU-ISI (31%) and all-cause mortality rate (13%). Analysis with Cox regression modeling showed that complicated ulcer healing (hazard ratio, 3.812; 95% confidence interval, 2.434-5.971) and initial DFU culture yielding MRSA (2.030; 1.452-2.838) predicted DFU-ISIs and that DFU-ISIs were associated with increased mortality risk (1.987; 1.106-3.568).

CONCLUSIONS

DFU-ISIs are important late complications of DFUs. Prevention of DFU-ISIs should be studied prospectively. Meanwhile, clinicians should aggressively incorporate treatment to accelerate ulcer healing and address MRSA into the care of diabetic patients with foot ulcers.

The emerging role of microdialysis in diabetic patients undergoing amputation for limb ischemia

Lower limb ischemia in diabetic patients is a result of macro- and microcirculation dysfunction. Diabetic patients undergoing limb amputation carry high mortality and morbidity rates, and decision making concerning the level of amputation is critical. Aim of this study is to evaluate a novel microdialysis technique to monitor tissue microcirculation preoperatively and predict the success of limb amputation in such patients. Overall, 165 patients with type 2 diabetes mellitus undergoing lower limb amputation were enrolled. A microdialysis catheter was placed preoperatively at the level of the intended flap for the stump reconstruction, and the levels of glucose, glycerol, lactate and pyruvate were measured for 24 consecutive hours. Patients were then amputated and monitored for 30 days regarding the outcome of amputation. Failure of amputation was defined as delayed healing or stump ischemia. Patients were divided into two groups based on the success of amputation. There was no difference between the two groups regarding gender, ASA score, body mass index, comorbidities, diagnostic modality used, level of amputation, as well as glucose, glycerol, and pyruvate levels. However, local concentrations of lactate were significantly different between the two groups and lactate/pyruvate (L/P) ratio was independently associated with failed amputation (threshold defined at 25.35). Elevated preoperative tissue L/P ratio is independently associated with worse outcomes in diabetic patients undergoing limb amputation. Therefore, preoperative tissue L/P ratio could be used as a predicting tool for limb amputation's outcome, although more clinical data are needed to provide safer conclusions.

Long-term mortality after lower-limb amputation

BACKGROUND

Mortality after amputation is known to be extremely high and is associated with a number of patient features. We wished to calculate this mortality after first-time lower-limb amputation and investigate whether any population or treatment factors are associated with worse mortality.

OBJECTIVE

To follow up individuals after lower limb amputation and ascertain the mortality rate as well as population or treatment features associated with mortality.

STUDY DESIGN

A prospective cohort study.

METHODS

Prospective lower-limb amputations over 1 year (N = 105) at a Regional Rehabilitation Centre were followed up for 3 years.

RESULTS

After 3 years, 35 individuals in the cohort had died, representing a mortality of 33%. On initial univariate analysis, those who died were more likely to have diabetes mellitus (χ(2) = 7.16, df = 1, p = 0.007) and less likely to have been fitted with a prosthesis (χ(2) = 5.84, df = 1, p = 0.016). There was no association with age, gender, level of amputation, social isolation, significant medical co-morbidity other than diabetes or presence of mood disorders. A multi-variable logistic regression (backward step) confirmed that diabetes (odds ratio = 3.04, confidence intervals = 1.25-7.40, p = 0.014) and absence of prosthesis-fitting (odds ratio = 2.60, confidence interval = 1.16-6.25, p = 0.028) were independent predictors of mortality.

CONCLUSION

Mortality after amputation is extremely high and is increased in individuals with diabetes or in those who are not fitted with a prosthesis after amputation.

CLINICAL RELEVANCE

The link between diabetes and mortality after amputation has been noted by others, but this is the first study to find an effect from prosthetic limb-wearing. This requires further investigation to ascertain why the wearing of a prosthetic limb, confers an independent survival benefit that is not related to the presence of medical co-morbidity.

Neuropathic Minimally Invasive Surgeries (NEMESIS):: Percutaneous Diabetic Foot Surgery and Reconstruction

Patients with peripheral neuropathy associated with ulceration are the nemesis of the orthopedic foot and ankle surgeon. Diabetic foot syndrome is the leading cause of peripheral neuropathy, and its prevalence continues to increase at an alarming rate. Poor wound healing, nonunion, infection, and risk of amputation contribute to the understandable caution toward this patient group. Significant metalwork is required to hold these technically challenging deformities. Neuropathic Minimally Invasive Surgeries is an addition to the toolbox of management of the diabetic foot. It may potentially reduce the risk associated with large wounds and bony correction in this patient group.

Inflammation as a Therapeutic Target for Diabetic Neuropathies

Diabetic neuropathies (DNs) are one of the most prevalent chronic complications of diabetes and a major cause of disability, high mortality, and poor quality of life. Given the complex anatomy of the peripheral nervous system and types of fiber dysfunction, DNs have a wide spectrum of clinical manifestations. The treatment of DNs continues to be challenging, likely due to the complex pathogenesis that involves an array of systemic and cellular imbalances in glucose and lipids metabolism. These lead to the activation of various biochemical pathways, including increased oxidative/nitrosative stress, activation of the polyol and protein kinase C pathways, activation of polyADP ribosylation, and activation of genes involved in neuronal damage, cyclooxygenase-2 activation, endothelial dysfunction, altered Na(+)/K(+)-ATPase pump function, impaired C-peptide-related signaling pathways, endoplasmic reticulum stress, and low-grade inflammation. This review summarizes current evidence regarding the role of low-grade inflammation as a potential therapeutic target for DNs.

Skin grafting and tissue replacement for treating foot ulcers in people with diabetes

BACKGROUND

Foot ulceration is a major problem in people with diabetes and is the leading cause of hospitalisation and limb amputations. Skin grafts and tissue replacements can be used to reconstruct skin defects for people with diabetic foot ulcers in addition to providing them with standard care. Skin substitutes can consist of bioengineered or artificial skin, autografts (taken from the patient), allografts (taken from another person) or xenografts (taken from animals).

OBJECTIVES

To determine the benefits and harms of skin grafting and tissue replacement for treating foot ulcers in people with diabetes.

SEARCH METHODS

In April 2015 we searched: The Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library); Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid EMBASE and EBSCO CINAHL. We also searched clinical trial registries to identify ongoing studies. We did not apply restrictions to language, date of publication or study setting.

SELECTION CRITERIA

Randomised clinical trials (RCTs) of skin grafts or tissue replacements for treating foot ulcers in people with diabetes.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed the quality of the included studies.

MAIN RESULTS

We included seventeen studies with a total of 1655 randomised participants in this review. Risk of bias was variable among studies. Blinding of participants, personnel and outcome assessment was not possible in most trials because of obvious differences between the treatments. The lack of a blinded outcome assessor may have caused detection bias when ulcer healing was assessed. However, possible detection bias is hard to prevent due to the nature of the skin replacement products we assessed, and the fact that they are easily recognisable. Strikingly, nearly all studies (15/17) reported industry involvement; at least one of the authors was connected to a commercial organisation or the study was funded by a commercial organisation. In addition, the funnel plot for assessing risk of bias appeared to be asymmetrical; suggesting that small studies with 'negative' results are less likely to be published.Thirteen of the studies included in this review compared a skin graft or tissue replacement with standard care. Four studies compared two grafts or tissue replacements with each other. When we pooled the results of all the individual studies, the skin grafts and tissue replacement products that were used in the trials increased the healing rate of foot ulcers in patients with diabetes compared to standard care (risk ratio (RR) 1.55, 95% confidence interval (CI) 1.30 to 1.85, low quality of evidence). However, the strength of effect was variable depending on the specific product that was used (e.g. EpiFix® RR 11.08, 95% CI 1.69 to 72.82 and OrCel® RR 1.75, 95% CI 0.61 to 5.05). Based on the four included studies that directly compared two products, no specific type of skin graft or tissue replacement showed a superior effect on ulcer healing over another type of skin graft or tissue replacement.Sixteen of the included studies reported on adverse events in various ways. No study reported a statistically significant difference in the occurrence of adverse events between the intervention and the control group.Only two of the included studies reported on total incidence of lower limb amputations. We found fewer amputations in the experimental group compared with the standard care group when we pooled the results of these two studies, although the absolute risk reduction for amputation was small (RR 0.43, 95% CI 0.23 to 0.81; risk difference (RD) -0.06, 95% CI -0.10 to -0.01, very low quality of evidence).

AUTHORS' CONCLUSIONS

Based on the studies included in this review, the overall therapeutic effect of skin grafts and tissue replacements used in conjunction with standard care shows an increase in the healing rate of foot ulcers and slightly fewer amputations in people with diabetes compared with standard care alone. However, the data available to us was insufficient for us to draw conclusions on the effectiveness of different types of skin grafts or tissue replacement therapies. In addition, evidence of long term effectiveness is lacking and cost-effectiveness is uncertain.

Study of Disease Progression and Relevant Risk Factors in Diabetic Foot Patients Using a Multistate Continuous-Time Markov Chain Model

The diabetic foot is a lifelong disease. The longer patients with diabetes and foot ulcers are observed, the higher the likelihood that they will develop comorbidities that adversely influence ulcer recurrence, amputation and survival (for example peripheral arterial disease, renal failure or ischaemic heart disease). The purpose of our study was to quantify person and limb-related disease progression and the time-dependent influence of any associated factors (present at baseline or appearing during observation) based on which effective prevention and/or treatment strategies could be developed. Using a nine-state continuous-time Markov chain model with time-dependent risk factors, all living patients were divided into eight groups based on their ulceration (previous or current) and previous amputation (none, minor or major) status. State nine is an absorbing state (death). If all transitions are fully observable, this model can be decomposed into eight submodels, which can be analyzed using the methods of survival analysis for competing risks. The dependencies of the risk factors (covariates) were included in the submodels using Cox-like regression. The transition intensities and relative risks for covariates were calculated from long-term data of patients with diabetic foot ulcers collected in a single specialized center in North-Rhine Westphalia (Germany). The detected estimates were in line with previously published, but scarce, data. Together with the interesting new results obtained, this indicates that the proposed model may be useful for studying disease progression in larger samples of patients with diabetic foot ulcers.

Foot Complications and Mortality: Results from Translating Research Into Action for Diabetes (TRIAD)

BACKGROUND

We sought to study the impact of foot complications on 10-year mortality independent of other demographic and biological risk factors in a racially and socioeconomically diverse managed-care population with access to high-quality medical care.

METHODS

We studied 6,992 patients with diabetes in Translating Research Into Action for Diabetes (TRIAD), a prospective observational study of diabetes care in managed care. Foot complications were assessed using administrative claims data. The National Death Index was searched for deaths across 10 years of follow-up (2000-2009).

RESULTS

Charcot's neuro-osteoarthropathy and diabetic foot ulcer with debridement were associated with an increased risk of mortality; however, the associations were not significant in fully adjusted models. Lower-extremity amputation (LEA) was associated with an increased risk of mortality in unadjusted (hazard ratio [HR], 3.21; 95% confidence interval [CI], 2.50-4.12) and fully adjusted (HR, 1.84; 95% CI, 1.28-2.63) models. When we examined the associations between LEA and mortality stratified by sex and race, risk was increased in men (HR, 1.96; 95% CI, 1.25-3.07), Hispanic individuals (HR, 5.17; 95% CI, 1.48-18.01), and white individuals (HR, 2.18; 95% CI, 1.37-3.47). In sensitivity analyses, minor LEA tended to increase the risk of mortality (HR, 1.48; 95% CI, 0.92-2.40), and major LEA was associated with a significantly higher risk of death at 10 years (HR, 1.89; 95% CI, 1.18-3.01).

CONCLUSIONS

In this managed-care population with access to high-quality medical care, LEA remained a robust independent predictor of mortality. The association was strongest in men and differed by race.

Baseline characteristics and risk factors for ulcer, amputation and severe neuropathy in diabetic foot at risk: the BRAZUPA study

BACKGROUND

Studies on diabetic foot and its complications involving a significant and representative sample of patients in South American countries are scarce. The main objective of this study was to acquire clinical and epidemiological data on a large cohort of diabetic patients from 19 centers from Brazil and focus on factors that could be associated with the risk of ulcer and amputation.

METHODS

This study presents cross sectional, baseline results of the BRAZUPA Study. A total of 1455 patients were included. Parameters recorded included age, gender, ethnicity, diabetes and comorbidity-related records, previous ulcer or amputation, clinical symptomatic score, foot classification and microvascular complications.

RESULTS

Patients with ulcer had longer disease duration (17.2 ± 9.9 vs. 13.2 ± 9.4 years; p < 0.001), and poorer glycemic control (HbA1c 9.23 ± 2.03 vs. 8.35 ± 1.99; p < 0.001). Independent risk factors for ulcer were male gender (OR 1.71; 95 % CI 1.2-3.7), smoking (OR 1.78; 95 % CI 1.09-2.89), neuroischemic foot (OR 20.34; 95 % CI 9.31-44.38), region of origin (higher risk for those from developed regions, OR 2.39; 95 % CI 1.47-3.87), presence of retinopathy (OR 1.68; 95 % CI 1.08-2.62) and absence of vibratory sensation (OR 7.95; 95 % CI 4.65-13.59). Risk factors for amputation were male gender (OR 2.12; 95 % CI 1.2-3.73), type 2 diabetes (OR 3.33; 95 % CI 1.01-11.1), foot at risk classification (higher risk for ischemic foot, OR 19.63; 95 % CI 3.43-112.5), hypertension (lower risk, OR 0.3; 95 % CI 0.14-0.63), region of origin (South/Southeast, OR 2.2; 95 % CI 1.1-4.42), previous history of ulcer (OR 9.66; 95 % CI 4.67-19.98) and altered vibratory sensation (OR 3.46; 95 % CI 1.64-7.33). There was no association between either outcome and ethnicity.

CONCLUSIONS

Ulcer and amputation rates were high. Age at presentation was low and patients with ulcer presented a higher prevalence of neuropathy compared to ischemic foot at risk. Ischemic disease was more associated with amputations. Ethnical differences were not of great importance in a miscegenated population.

Growth factors for treating diabetic foot ulcers

BACKGROUND

Foot ulcers are a major complication of diabetes mellitus, often leading to amputation. Growth factors derived from blood platelets, endothelium, or macrophages could potentially be an important treatment for these wounds but they may also confer risks.

OBJECTIVES

To assess the benefits and harms of growth factors for foot ulcers in patients with type 1 or type 2 diabetes mellitus.

SEARCH METHODS

In March 2015 we searched the Cochrane Wounds Group Specialised Register, The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), Ovid MEDLINE, Ovid MEDLINE (In-Process & Other Non-Indexed Citations, Ovid EMBASE and EBSCO CINAHL. There were no restrictions with respect to language, date of publication or study setting.

SELECTION CRITERIA

Randomised clinical trials in any setting, recruiting people with type 1 or type 2 diabetes mellitus diagnosed with a foot ulcer. Trials were eligible for inclusion if they compared a growth factor plus standard care (e.g., antibiotic therapy, debridement, wound dressings) versus placebo or no growth factor plus standard care, or compared different growth factors against each other. We considered lower limb amputation (minimum of one toe), complete healing of the foot ulcer, and time to complete healing of the diabetic foot ulcer as the primary outcomes.

DATA COLLECTION AND ANALYSIS

Independently, we selected randomised clinical trials, assessed risk of bias, and extracted data in duplicate. We estimated risk ratios (RR) for dichotomous outcomes. We measured statistical heterogeneity using the I(2) statistic. We subjected our analyses to both fixed-effect and random-effects model analyses.

MAIN RESULTS

We identified 28 randomised clinical trials involving 2365 participants. The cause of foot ulcer (neurologic, vascular, or combined) was poorly defined in all trials. The trials were conducted in ten countries. The trials assessed 11 growth factors in 30 comparisons: platelet-derived wound healing formula, autologous growth factor, allogeneic platelet-derived growth factor, transforming growth factor β2, arginine-glycine-aspartic acid peptide matrix, recombinant human platelet-derived growth factor (becaplermin), recombinant human epidermal growth factor, recombinant human basic fibroblast growth factor, recombinant human vascular endothelial growth factor, recombinant human lactoferrin, and recombinant human acidic fibroblast growth factor. Topical intervention was the most frequent route of administration. All the trials were underpowered and had a high risk of bias. Pharmaceutical industry sponsored 50% of the trials.Any growth factor compared with placebo or no growth factor increased the number of participants with complete wound healing (345/657 (52.51%) versus 167/482 (34.64%); RR 1.51, 95% CI 1.31 to 1.73; I(2) = 51%, 12 trials; low quality evidence). The result is mainly based on platelet-derived wound healing formula (36/56 (64.28%) versus 7/27 (25.92%); RR 2.45, 95% 1.27 to 4.74; I(2) = 0%, two trials), and recombinant human platelet-derived growth factor (becaplermin) (205/428 (47.89%) versus 109/335 (32.53%); RR 1.47, 95% CI 1.23 to 1.76, I(2)= 74%, five trials).In terms of lower limb amputation (minimum of one toe), there was no clear evidence of a difference between any growth factor and placebo or no growth factor (19/150 (12.66%) versus 12/69 (17.39%); RR 0.74, 95% CI 0.39 to 1.39; I(2) = 0%, two trials; very low quality evidence). One trial involving 55 participants showed no clear evidence of a difference between recombinant human vascular endothelial growth factor and placebo in terms of ulcer-free days following treatment for diabetic foot ulcers (RR 0.64, 95% CI 0.14 to 2.94; P value 0.56, low quality of evidence)Although 11 trials reported time to complete healing of the foot ulcers in people with diabetes , meta-analysis was not possible for this outcome due to the unique comparisons within each trial, failure to report data, and high number of withdrawals. Data on quality of life were not reported. Growth factors showed an increasing risk of overall adverse event rate compared with compared with placebo or no growth factor (255/498 (51.20%) versus 169/332 (50.90%); RR 0.83; 95% CI 0.72 to 0.96; I(2) = 48%; eight trials; low quality evidence). Overall, safety data were poorly reported and adverse events may have been underestimated.

AUTHORS' CONCLUSIONS

This Cochrane systematic review analysed a heterogeneous group of trials that assessed 11 different growth factors for diabetic foot ulcers. We found evidence suggesting that growth factors may increase the likelihood that people will have complete healing of foot ulcers in people with diabetes. However, this conclusion is based on randomised clinical trials with high risk of systematic errors (bias). Assessment of the quality of the available evidence (GRADE) showed that further trials investigating the effect of growth factors are needed before firm conclusions can be drawn. The safety profiles of the growth factors are unclear. Future trials should be conducted according to SPIRIT statement and reported according to the CONSORT statement by independent investigators and using the Foundation of Patient-Centered Outcomes Research recommendations.

National trends in incidence and outcomes in lower extremity amputations in people with and without diabetes in Spain, 2001-2012

AIMS

To describe trends in the incidence and outcomes of lower-extremity amputations (LEAs) in patients with T1DM and T2DM in Spain, 2001-2012.

METHODS

We used national hospital discharge data. Incidence of discharges attributed to LEA procedures were calculated stratified by diabetes status and type of LEA. Joinpoint log-linear regression for incidence trends and logistic regression for factors associated with in-hospital mortality were used.

RESULTS

From 2001 to 2012, 73,302 minor LEAs and 64,710 major LEAs were performed. We found that incidence of minor LEA procedures in T1DM patients decreased by 9.84% per year from 2001 to 2008 and then remained stable through 2012. In T2DM patients, LEA increased by 1.89% per year over the entire study period. Among patients with T1DM, major LEA incidence rate decreased by 10.5% from 2001 to 2012. In patients with T2DM, it increased by 4.29% from 2001 to 2004, and then decreased by 1.85% through 2012. In-hospital mortality after major or minor LEAs was associated with older age in all groups and with being female in T2DM and in people without diabetes.

CONCLUSIONS

Our national data show a decrease in the incidence of minor LEAs in patients with diabetes and in major LEAS in patients with T1DM over the period of study. In patients with T2DM, we found a decrease between 2004 and 2012. An additional improvement in preventive care, such as the introduction of diabetes foot units in hospitals, is necessary.

The major predictors of amputation and length of stay in diabetic patients with acute foot ulceration

BACKGROUND

Diabetic foot infections are associated with substantial morbidity and mortality. Prediction of diabetic foot ulcer outcome may be helpful for optimizing management strategy. This study aimed to determine the major predictors of amputation and length of stay in diabetic patients with acute foot ulceration.

METHODS

A total of 55 type 2 diabetic patients with diabetic foot infection were enrolled. The patients were evaluated according to the Infectious Diseases Society of America and International Working Group on the Diabetic Foot criteria and also the Wagner's classification. Blood samples were taken at the start of hospitalization for the measurement of glucose, hemoglobin A1C (HbA1C), white blood cells (WBC), C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR). Length of stay in hospital was recorded.

RESULTS

WBC and CRP were significantly higher in lower-extremity amputation (LEA) group (p = 0.001 and p = 0.008, respectively); also, ESR was higher in this group, but there was no statistical significance. Wagner grade and infection severity were significantly higher in the LEA group as compared with the non-LEA group (both p values < 0.001). Glycemic control parameters (i.e., HbA1C, plasma glucose) were not different in LEA and non-LEA groups. In correlation analyses, amputation rate was negatively correlated (r = - 0.512, p < 0.001) with length of stay. WBC, ESR, CRP, Wagner grade, and severity of infection showed positive correlation with length of stay (r = 0.493, p < 0.001; r = 0.271, p = 0.045; r = 0.299, p = 0.027; r = 0.434, p = 0.001; and r = 0.464, p < 0.001, respectively).

CONCLUSIONS

Baseline levels of acute-phase reactants, especially CRP, WBC, ESR, and increased Wagner grade, appeared to be helpful in predicting amputation and length of stay in diabetic patients with acute foot ulceration. However, duration of diabetes and glucose control seems to have no effect.

Migratory activity of circulating mononuclear cells is associated with cardiovascular mortality in type 2 diabetic patients with critical limb ischemia

OBJECTIVE

Prediction of clinical outcome in diabetic patients with critical limb ischemia (CLI) is unsatisfactory. This prospective study investigates if the abundance and migratory activity of a subpopulation of circulating mononuclear cells, namely, CD45(dim)CD34(pos)CXCR4(pos)KDR(pos) cells, predict major amputation and cardiovascular death in type 2 diabetic patients undergoing percutaneous transluminal angioplasty for CLI.

RESEARCH DESIGN AND METHODS

A consecutive series of 119 type 2 diabetic patients with CLI was enrolled. CD45(dim)CD34(pos)CXCR4(pos)KDR(pos) cells were assessed by flow cytometry upon isolation and also after spontaneous or stromal cell-derived factor 1α-directed migration in an in vitro assay. The association between basal cell counts and migratory activity and the risk of an event at 18-month follow-up was evaluated in a multivariable regression analysis.

RESULTS

Time-to-event analysis of amputation (n = 13) showed no association with the candidate predictors. Sixteen cardiovascular deaths occurred during 18 months of follow-up. Abundance of CD45(dim)CD34(pos)CXCR4(pos)KDR(pos) cells was not associated with cardiovascular mortality. Interestingly, in vitro migration of CD45(dim)CD34(pos)CXCR4(pos)KDR(pos) cells was higher in patients with cardiovascular death compared with event-free subjects (percentage of migrated cells median value and interquartile range, 0.03 [0.02-0.07] vs. 0.01 [0.01-0.03]; P = 0.0095). Multivariable regression model analysis showed that cell migration forecasts cardiovascular mortality independently of other validated predictors, such as age, diagnosed coronary artery disease, serum C-reactive protein, and estimated glomerular filtration rate. In this model, doubling of migrated cell counts increases the cardiovascular death hazard by 100% (P < 0.0001).

CONCLUSIONS

The new predictor could aid in the identification of high-risk patients with type 2 diabetes requiring special diagnostic and therapeutic care after revascularization.

Risk factors for ulceration and amputation in diabetic foot: study in a cohort of 496 patients

Treatment strategies for foot at risk and diabetic foot are mainly preventive. Studies describing demographic data, clinical and impacting factors continue to be, however, scarce. Our objective was to determine the epidemiological presentation of diabetic foot and understand whether there were easily assessable variables capable of predicting the development of diabetic foot. This was a retrospective study of 496 patients with established foot at risk or diabetic foot, who were evaluated based on age, gender, type and duration of diabetes, foot at risk classification, and the presence of deformities, ulceration, and amputation. The presence of deformities, ulceration, and amputation was recorded in 45.9, 25.3, and 12.9 % of patients, respectively. As for diabetic foot classification, the great majority of our cohort had diabetic neuropathy (92.9 %). Approximately 30 % had neuro-ischemic disease and only 7.1 % had ischemic disease alone. Sixty-two percent of patients presented neuropathy with no signs of arteriopathy. Foot classification was as a significant predictor for the presence of ulcer (p = 0.009; OR = 3.2; 95 % CI = 1.18-7.3). Only male gender was a significant predictor for ulceration (p < 0.001). Predictors of amputation were male gender (p < 0.001; OR = 3.44 95 % CI = 1.81-6.56) and neuro-ischemic diabetic foot (p < 0.049; OR = 4.6; 95 % CI = 1.01-20.9). The predictors for diabetic foot were male gender and the presence of neuropathy. The combination of neuropathy and peripheral vascular disease adds significantly to the risk for amputation among patients with the diabetic foot syndrome. Men, presenting combined risk factors, should be a group receiving special attention and in the foot clinic, due to their potentially worse evolution.

Distal amputations for the diabetic foot

Minor amputations in diabetic patients with foot complications have been well studied in the literature but controversy still remains as to what constitutes successful or non-successful limb salvage. In addition, there is a lack of consensus on the definition of a minor or distal amputation and a major or proximal amputation for the diabetic population. In this article, the authors review the existing literature to evaluate the efficacy of minor amputations in this selected group of patients in terms of diabetic limb salvage and also propose several definitions regarding diabetic foot amputations.

A multidisciplinary approach and surgical tips in major amputations of diabetic patients

We aim to describe the results obtained in major amputations (transtibial and transfemoral) of diabetic patients followed with a close combined approach (medical and surgical). We evaluated 37 cases with an average age of 73.55 years. All were admitted in our Diabetology Department where they were monitored and treated in order to reach a new balance concerning cardiac failure, anemia, and other pathologies. Then, the orthopedic surgeons operate choosing an adequate level for amputation and pointing about adequate stump covering, accurate vessel, perineural and periosteal hemostasis, and nerve thermoablation. Reading literature we discovered in our series an improvement concerning perioperative mortality, considering the high average age and the bad general conditions of our patients; at the same time, we obtained an improvement about neuromas and ghost limb syndrome versus literature. About walking capabilities we had similar results compared to previous papers, obtaining the worst results for thigh amputations.