Lower-extremity amputations in diabetic and nondiabetic patients. A population-based study in eastern Finland

The Influence of Diabetes Mellitus on Mortality of Patients After Lower Extremity Amputation: A Systematic Review and Meta-analysis

OBJECTIVE

The influence of diabetes mellitus (DM) on mortality following lower extremity amputation (LEA) remains controversial. This systematic review and meta-analysis aimed to determine the influence of DM on long-term mortality (LTM) and short-term mortality (STM) after amputation.

MATERIALS AND METHODS

The Medline, the Cochrane library, and Embase databases were searched. The primary and secondary outcomes were LTM and STM following amputation. One-year and 30-day all-cause mortality after amputation were considered as LTM and STM, respectively. A random-effects model was utilized to pool results. To evaluate the stability of results, subgroup analyses and sensitivity analyses were conducted.

RESULTS

Twenty-three cohort studies with a total of 58,219 patients were included, among which 31,750 (54.5%) patients had DM. The mean score of included studies evaluated by Newcastle-Ottawa Scale was 7.65, indicating moderate to high quality. The pooled results showed no significant difference in 1-year LTM (risk ratio [RR], 0.96; 95% CI 0.86-1.07) after amputation. However, 3-year (RR, 1.22; 95% CI 1.01-1.47) and 5-year (RR, 1.18; 95% CI 1.07-1.31) LTMs of DM patients were obviously higher than that of NDM (non-diabetes mellitus) patients. The STM of the DM group was significantly lower than the NDM group (RR, 0.80; 95% CI 0.64-0.98).

CONCLUSIONS

The current study revealed that DM patients had an obvious lower STM following LEA, but the risk of DM on LTM after amputation was gradually increased with time. More attention should be paid to the long-term survival of DM patients after LEA.

Pathological gait in partial foot amputation versus peripheral neuropathy

Partial foot amputation (PFA) is a common surgical loss of part of either the forefoot or mid-foot. It is usually the sequel to a cascade of physiological foot dysfunction such as peripheral neuropathy (PN). The gait compensation mechanisms associated with these foot disorders aren't well understood yet.

PURPOSE

The aim of the study was to evaluate pathological gait compensation mechanisms in PFA due to PN versus PN alone through a comprehensive gait analysis.

METHODS

Plantar pressure, GRF, load distribution, footprint length and area, foot progression angle, step length, percentage of double limb support, and stance time were measured on 53 participants assigned into two well-matched groups: (A) 25 subjects with healed unilateral PFA and (B) 28 subjects with PN without ulcer. The gait analysis was conducted at a self-preferred walking speed using the FREEMED baropodometric platform and FREESTEP software.

RESULTS

The PFA group showed a significant decrease in load over the remaining toes and metatarsal heads compared to the PN group (p = .001 and p = .003, respectively). Conversely, the PFA group showed a significant increase in load over the mid-foot and peak plantar pressure during mid-stance (p = .007 and p = .016, respectively). All other measured variables showed no significant difference between the two groups (p > .05).

CONCLUSION

Individuals with PFA and PN or PN alone tend to shift their body loads posteriorly and redistribute their loads to compensate for the insufficient support from the forefoot. The PFA group was worse than the PN group. Furthermore, the PFA may not be the primary cause of the altered gait but rather the underlying systemic disease. The PFA surgery only worsens the compensatory mechanism.

Diabetes mellitus in peripheral artery disease: Beyond a risk factor

Peripheral artery disease (PAD) is one of the major cardiovascular diseases that afflicts a large population worldwide. PAD results from occlusion of the peripheral arteries of the lower extremities. Although diabetes is a major risk factor for developing PAD, coexistence of PAD and diabetes poses significantly greater risk of developing critical limb threatening ischemia (CLTI) with poor prognosis for limb amputation and high mortality. Despite the prevalence of PAD, there are no effective therapeutic interventions as the molecular mechanism of how diabetes worsens PAD is not understood. With increasing cases of diabetes worldwide, the risk of complications in PAD have greatly increased. PAD and diabetes affect a complex web of multiple cellular, biochemical and molecular pathways. Therefore, it is important to understand the molecular components that can be targeted for therapeutic purposes. In this review, we describe some major developments in enhancing the understanding of the interactions of PAD and diabetes. We also provide results from our laboratory in this context.

Endothelial-to-mesenchymal transition: An underappreciated mediator of diabetic complications

Diabetes and its complications represent a great burden on the global healthcare system. Diabetic complications are fundamentally diseases of the vasculature, with endothelial cells being the centerpiece of early hyperglycemia-induced changes. Endothelial-to-mesenchymal transition is a tightly regulated process that results in endothelial cells losing endothelial characteristics and developing mesenchymal traits. Although endothelial-to-mesenchymal transition has been found to occur within most of the major complications of diabetes, it has not been a major focus of study or a common target in the treatment or prevention of diabetic complications. In this review we summarize the importance of endothelial-to-mesenchymal transition in each major diabetic complication, examine specific mechanisms at play, and highlight potential mechanisms to prevent endothelial-to-mesenchymal transition in each of the major chronic complications of diabetes.

Debridement of Diabetic Foot Ulcers

Diabetic foot ulcerations have devastating complications, including amputations, poor quality of life, and life-threatening infections. Diabetic wounds can be protracted, take significant time to heal, and can recur after healing. They are costly consuming health care resources. These consequences have serious public health and clinical implications. Debridement is often used as a standard of care. Debridement consists of both nonmechanical (autolytic, enzymatic) and mechanical methods (sharp/surgical, wet to dry debridement, aqueous high-pressure lavage, ultrasound, and biosurgery/maggot debridement therapy). It is used to remove nonviable tissue, to facilitate wound healing, and help prevent these serious outcomes. What are the various forms and rationale behind debridement? This article comprehensively reviews cutting-edge methods and the science behind debridement and diabetic foot ulcers.

Two-Stage Gene Therapy (VEGF, HGF and ANG1 Plasmids) as Adjunctive Therapy in the Treatment of Critical Lower Limb Ischemia in Diabetic Foot Syndrome

One of the most serious problems in people with diabetes is diabetic foot syndrome. Due to the peripheral location of atherosclerotic lesions in the arterial system of the lower extremities, endovascular treatment plays a dominant role. However, carrying out these procedures is not always possible and does not always bring the expected results. Gene therapy, which stimulates angiogenesis, improves not only the inflow from the proximal limb but also the blood redistribution in individual angiosomes. Due to the encouraging results of sequential treatment consisting of intramuscular injections of VEGF/HGF bicistronic plasmids followed by a month of ANG1 plasmids, we decided to use the described method for the treatment of critical ischemia of the lower limbs in the course of diabetes and, more specifically, in diabetic foot syndrome. Twenty-four patients meeting the inclusion criteria were enrolled in the study. They were randomly divided into two equal groups. The first group of patients was subjected to gene therapy, where the patients received intramuscular injections of pIRES/VEGF165/HGF plasmids and 1 month of ANG-1 plasmids. The remaining patients constituted the control group. Gene therapy was well tolerated by most patients. The wounds healed significantly better in Group 1. The minimal value of ABI increased significantly in Group 1 from 0.44 ± 0.14 (± standard deviation) to 0.47 ± 0.12 (with p = 0.028) at the end of the study. There were no significant differences in the control group. In the gene treatment group, PtcO2 increased significantly (from 28.71 ± 10.89 mmHg to 33.9 ± 6.33 mmHg with p = 0.001), while in Group 2, no statistically significant changes were found. The observed resting pain decreased significantly in both groups (Group 1 decreased from 6.80 ± 1.48 to 2.10 ± 1.10; p < 0.001; the control group decreased from 7.44 ± 1.42 to 3.78 ± 1.64 with p < 0.001). In our study, we evaluated the effectiveness of gene therapy with the growth factors described above in patients with CLI in the course of complicated DM. The therapy was shown to be effective with minimal side effects. No serious complications were observed.

Relationship between cognitive function in individuals with diabetic foot ulcer and mortality

BACKGROUND

Diabetic foot ulcer (DFU) is a common diabetes mellitus (DM) complication. Individuals with DM and a DFU achieved significantly lower scores in cognitive tests than those without a DFU. We investigated whether baseline cognitive function in individuals with a DFU is a determinant of mortality.

METHODS

A prospective study using data collected during a case-control study conducted in 2010-2012 whereby 90 participants with a DFU (mean age at baseline 58.28 ± 6.95 years, 75.6% male) took the paper and pencil and the NeuroTrax battery of cognitive tests. Depression was assessed, and the DFU status was evaluated. In 2020, information pertaining to participants' vital status (dead/alive) was collected and the relationship between baseline cognitive status and vital status was assessed.

RESULTS

During a median follow-up of 6.8 years (range 0.2-9.5), 39 participants died (43.3%). Individuals alive vs. those who had died during follow-up had a higher global cognitive score at baseline (92.16 ± 10.95 vs. 87.18 ± 12.24, p = 0.045), but increased risk was not found. Individuals who were alive vs. those who had died during follow-up had statistically significantly higher baseline executive function, reaction time and digit symbol substitution test results. However, after adjustment for glycosylated hemoglobin (HbA1c), microvascular and macrovascular complications, no relationship between cognitive tests and mortality remained significant.

CONCLUSIONS

The higher mortality rate among people with type 2 DM and a DFU was not significant after adjustment for HbA1c, micro- and macrovascular complications. There may be common pathophysiological pathways to both DM complications and cognitive impairment, which may contribute to increased mortality. Further studies are warranted.

Foot Osteomyelitis Location and Rates of Primary or Secondary Major Amputations in Patients With Diabetes

BACKGROUND

Diabetic foot osteomyelitis (DFO) often leads to amputations in the lower extremity. Data on the influence of the initial anatomical DFO localization on ultimate major amputation are limited.

METHODS

In this retrospective analysis, 583 amputation episodes in 344 patients (78 females, 266 males) were analyzed. All received a form of amputation in combination with antibiotic therapy. A multivariate logistic regression analysis with the primary outcome "major amputation" defined as an amputation above the ankle joint was performed. The association of risk factors including location of DFO, coronary artery disease, peripheral artery disease, neuropathy, nephropathy, and Charcot neuro-osteoarthropathy was analyzed.

RESULTS

Among 583 episodes, DFO was located in the forefoot in 512 (87.8%), in the midfoot in 43 (7.4%), and in the hindfoot in 28 episodes (4.8%). Overall, 53 of 63 (84.1%) major amputations were performed because of DFO in the setting of peripheral artery disease as primary indication. Overall, limb loss occurred in 6.1% (31/512) of forefoot, 20.9% (9/43) of midfoot, and 46.4% (13/28) of hindfoot DFO. Among these, 22 (41.5%) were performed as the primary treatment, whereas 31 (58.5%) followed previously failed minor amputations. Among this latter group of secondary major amputations, the DFO was localized to the forefoot in 23 of 583 (3.9%), the midfoot in 4 of 583 (0.7%) and the hindfoot in 4 of 583 (0.7%). In multivariate logistic regression analysis, initial hindfoot localization was a significant factor (P < .05), whereas peripheral artery disease, smoking, and a midfoot DFO were not found to be risk factors.

CONCLUSION

In our retrospective series, the frequency of limb loss in DFO increased with more proximal initial foot DFO lesions, with almost half of patients losing their limbs with a hindfoot DFO.

LEVEL OF EVIDENCE

Level IV, retrospective cohort study.

Trans tibial amputation with or without a tourniquet in patients with diabetic foot infection and peripheral vascular disease: Comparison of postoperative outcomes

Background: Transtibial amputation (TTA) due to complications of diabetic foot infection (DFI) or peripheral vascular disease (PVD) is a high-risk procedure in fragile patients. The risks of reoperation, blood loss requiring blood transfusion, and mortality are high. The use of a tourniquet in this procedure is controversial and scarcely reported. Objective: this study aimed to compare the outcomes of TTAs with or without a tourniquet in a single tertiary medical center. Methods: We retrospectively identified all patients who had undergone TTA in our institution (1/2019-1/2020) and included only those who underwent the procedure due to complications of DFI or PVD (n = 69). The retrieved data included demographics, comorbidities, ASA score, the use of a tourniquet, operation duration, pre- and postoperative hemoglobin levels, administration of blood transfusions, hospitalization length, surgical site infection and 60-days reoperation and mortality rates. Results: TTA with a tourniquet was superior to TTA without a tourniquet in reducing the average operation length by 11 min (p = 0.05), the median postoperative hospitalization by 6 days (p = 0.04), and the use of blood transfusions (odds ratio [OR] = 0.176, 95% confidence interval [CI]: 0.031-0.996). Conclusions: Our findings demonstrated advantages in operative time, hospitalization length, and blood transfusion requirement for TTA with a tourniquet compared to TTA without a tourniquet.

Amputation as a First Treatment is Highly Associated With Late Presentation: An Underestimated Modifiable Major Risk Factor for Diabetic Foot Ulcer

PURPOSE

Several risk factors for lower extremity amputation in diabetic patients have been identified; however, late presentation has been poorly investigated. Very few studies looked at the impact of such risk factor. As none has investigated the link between admission to amputation and late presentation in this population, we investigated such association.

METHODS

The study is a retrospective comparative cohort of continuous series of patients admitted for amputation related to diabetic foot ulcer (DFU) as a first treatment. A late presentation was defined as a period of 3 weeks or more from the onset of the ulcer.

RESULTS

Forty-six patients admitted for amputation and all wounds were infected and located on the plantar forefoot in 32 cases (69.5%), on the toes in 10 cases (21.7%), and in the heel area in 4 cases (8.8%). The mean duration to admission was 5.2 ±1.8 weeks (range 4-10 weeks). Late presentation was recorded in 42 (91.3%) patients.

CONCLUSION

This study demonstrates that amputation due to DFU is highly associated with late presentation. Educational campaigns targeting patient and first-line health care providers and highlighting the urgency of diabetic ulcers are needed to impact this major modifiable risk factor.Levels of Evidence: Therapeutic, Level III: Retrospective Comparative.

Oxygen-Releasing Composites: A Promising Approach in the Management of Diabetic Foot Ulcers

In diabetes, lower extremity amputation (LEA) is an irreversible diabetic-related complication that easily occurs in patients with diabetic foot ulcers (DFUs). Because DFUs are a clinical outcome of different causes including peripheral hypoxia and diabetic foot infection (DFI), conventional wound dressing materials are often insufficient for supporting the normal wound healing potential in the ulcers. Advanced wound dressing development has recently focused on natural or biocompatible scaffolds or incorporating bioactive molecules. This review directs attention to the potential of oxygenation of diabetic wounds and highlights current fabrication techniques for oxygen-releasing composites and their medical applications. Based on different oxygen-releasable compounds such as liquid peroxides and solid peroxides, for example, a variety of oxygen-releasing composites have been fabricated and evaluated for medical applications. This review provides the challenges and limitations of utilizing current oxygen releasable compounds and provides perspectives on advancing oxygen releasing composites for diabetic-related wounds associated with DFUs.

The combined impact of ankle-brachial index and transcutaneous oxygen pressure on mortality in patients with type 2 diabetes and foot ulcers

AIMS

A diabetic foot ulcer (DFU) is associated with increased cardiovascular risk and mortality, independently of ulcer etiology (ischemic, neuro-ischemic or neuropathic). Ankle-brachial index (ABI) is the most commonly used test when diagnosing peripheral macrovascular disease and is a well-known marker for increased cardiovascular risk. Transcutaneous oxygen pressure (TcPO₂) is considered to better evaluate microvascular function and has in previous studies shown correlations with both wound healing and survival. The aim of this study was to evaluate the combined impact of a low TcPO₂ (<30 mmHg) and a pathological ABI (<0.9 or ≥1.4) on three-year mortality in patients with DFU.

METHODS

Type 2 diabetes patients aged <90 years, with at least one DFU who underwent vascular assessment with ABI and TcPO₂ were screened for participation. The primary endpoint was mortality after three years, assessed from the National Death Registry in Sweden.

RESULTS

The study enrolled 235 participants with a median age of 76 years. Individuals with either an abnormally high or low ABI in combination with a low TcPO₂ had the worst survival rates, with three-year mortality of 54%, compared to 42% in those with one abnormal variable (either ABI or TcPO₂), and 21% in those with normal ABI and TcPO₂.

CONCLUSIONS

Combining ABI and TcPO₂ when risk stratifying DFU patients seems to provide additional predictive information, not only concerning ulcer healing and limb salvage, but also on survival.

Advances in Revascularization for Peripheral Artery Disease: Revascularization in PAD

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

Minor vs. major leg amputation in adults with diabetes: Six-month readmissions, reamputations, and complications

AIMS

The objective of this study was comparing medium-term outcomes between comparable minor and major amputations in adults with diabetes.

METHODS

We used data from the 2016-2017 National Readmissions Database to construct a representative cohort of 15,581 adults with diabetes with lower extremity amputations. Patients were categorized by level of index amputation (major/minor), and propensity score matched to compare outcomes in candidates for either level of amputation. Readmission and reamputations were assessed at 1, 3, and 6 months following index amputation.

RESULTS

In the 6 months following index amputation, large proportions of patients were readmitted (n = 7597, 48.8%) or had reamputations (n = 1990, 12.8%). Patients with minor amputations had greater odds of readmission (OR = 1.25; 95% CI 1.18-1.31), reamputation (OR = 3.71; 95% CI 3.34-4.12), and more proximal reamputation (OR = 2.61; 95% 2.33-2.93) (all P < 0.001). Further, minor amputation patients had higher and lower odds of readmission for postoperative infection (OR = 4.45; 95% CI 3.27-6.05), or sepsis (OR = 0.79; 95% CI 0.68-0.93), respectively.

CONCLUSION

Patients desire to save as much limb as possible and should be counseled on higher risk for reamputation, readmission, and infection with minor amputations.

Acidified Nitrite Accelerates Wound Healing in Type 2 Diabetic Male Rats: A Histological and Stereological Evaluation

Impaired skin nitric oxide production contributes to delayed wound healing in type 2 diabetes (T2D). This study aims to determine improved wound healing mechanisms by acidified nitrite (AN) in rats with T2D. Wistar rats were assigned to four subgroups: Untreated control, AN-treated control, untreated diabetes, and AN-treated diabetes. AN was applied daily from day 3 to day 28 after wounding. On days 3, 7, 14, 21, and 28, the wound levels of vascular endothelial growth factor (VEGF) were measured, and histological and stereological evaluations were performed. AN in diabetic rats increased the numerical density of basal cells (1070 ± 15.2 vs. 936.6 ± 37.5/mm³) and epidermal thickness (58.5 ± 3.5 vs. 44.3 ± 3.4 μm) (all p < 0.05); The dermis total volume and numerical density of fibroblasts at days 14, 21, and 28 were also higher (all p < 0.05). The VEGF levels were increased in the treated diabetic wounds at days 7 and 14, as was the total volume of fibrous tissue and hydroxyproline content at days 14 and 21 (all p < 0.05). AN improved diabetic wound healing by accelerating the dermis reconstruction, neovascularization, and collagen deposition.

Age- and sex-specific incidence of non-traumatic lower limb amputation in patients with type 2 diabetes mellitus in a U.S. claims database

AIM

To estimate age- and sex-specific incidence rates (IRs) of non-traumatic lower limb amputations (LLA) in patients with type 2 diabetes mellitus (T2DM) using a claims database from the United States (US).

METHODS

Patients with T2DM 18 years and older were identified using the Truven Health MarketScan database from January 1, 2007 to September 30, 2018. The overall and age- and sex-specific IRs of all non-traumatic LLA, minor LLA (amputation at or below the ankle), and major LLA (amputation above ankle) were calculated.

RESULTS

Among the 6,117,981 patients with T2DM, 14,627 LLA events occurred (minor LLA; 72.8%; major LLA: 27.2%). The IRs (95% CI) of all LLA, minor LLA, and major LLA per 1000 person-years or PY were 0.86 (0.85, 0.88), 0.63 (0.62, 0.64), and 0.23 (0.23, 0.24), respectively. The IR (95% CI) of all LLA per 1000 PY in males was higher compared to females [1.24 (1.22, 1.26) vs. 0.46 (0.45, 0.48)]. The incidence of all LLA increased with an increasing age (highest IR in age-group of ≥80 years).

CONCLUSIONS

This study identified males and older patients with T2DM at higher risk of developing LLA in the US, warranting further exploration of risk factors of LLA in these subgroups.

Novel Long Noncoding RNA lnc-URIDS Delays Diabetic Wound Healing by Targeting Plod1

Impaired wound healing is one of the main causes of diabetic foot ulcerations. However, the exact mechanism of delayed wound healing in diabetes is not fully understood. Long noncoding RNAs (lncRNAs) are widely involved in a variety of biological processes and diseases, including diabetes and its associated complications. In this study, we identified a novel lncRNA, MRAK052872, named lncRNA UpRegulated in Diabetic Skin (lnc-URIDS), which regulates wound healing in diabetes. lnc-URIDS was highly expressed in diabetic skin and dermal fibroblasts treated with advanced glycation end products (AGEs). lnc-URIDS knockdown promoted migration of dermal fibroblasts under AGEs treatment in vitro and accelerated diabetic wound healing in vivo. Mechanistically, lnc-URIDS interacts with procollagen-lysine, 2-oxoglutarate 5-dioxygenase 1 (Plod1), a critical enzyme responsible for collagen cross-linking. The binding of lnc-URIDS to Plod1 results in a decreased protein stability of Plod1, which ultimately leads to the dysregulation of collagen production and deposition and delays wound healing. Collectively, this study identifies a novel lncRNA that regulates diabetic wound healing by targeting Plod1. The findings of the current study offer some insight into the potential mechanism for the delayed wound healing in diabetes and provide a potential therapeutic target for diabetic foot.

Increased Mortality Risk in People with Type 2 Diabetes Mellitus in Lithuania

This retrospective cohort study aimed to analyze overall and cause-specific mortality risk in people with type 2 diabetes mellitus (T2DM) in Lithuania. Information on the diagnosis of T2DM and glucose-lowering medication was obtained from the National Health Insurance Fund database, causes of death–from death certificates. Sex, age, and calendar period-standardized mortality ratios (SMRs) were calculated. In addition, 89,512 patients were followed-up between 2010 and 2017, contributing to the observation period of 592,321 person-years. Overall mortality risk was increased for both sexes (overall SMR = 1.35, 95% confidence interval (CI) 1.34–1.37). Greatest mortality risk was in the age group of 40–49 years at diabetes diagnosis (SMR = 1.68, 95% CI 1.60–1.76) and among those who had died before the age of 50 (SMR = 22.04, 95% CI 18.82–25.81). Patients treated with insulin only had the highest SMR (2.43, 95% CI 2.32–2.55). Mortality risk increased with increasing diabetes duration and was higher in women in all these groups. The highest cause-specific SMRs were infection-related causes (SMR = 1.44), particularly septicemia (SMR = 1.78), diseases of the circulatory system (SMR = 1.42), especially ischemic heart (SMR = 1.46) and cerebrovascular diseases (SMR = 1.38), as well as diseases of the digestive system (SMR = 1.35). Cancer mortality risk was elevated for women (SMR = 1.13), but not for men (SMR = 0.93). In conclusion, people with T2DM had an excess mortality risk, which was higher in women compared to men, younger people, in those who were diagnosed with T2DM at a younger age, had longer diabetes duration, and who required treatment with insulin.

A meta-analysis of mortality after minor amputation among patients with diabetes and/or peripheral vascular disease

OBJECTIVE

Foot complications in patients with diabetes or peripheral artery disease (PAD) are serious events in the life of these patients that often lead to amputations and mortality. No evidence synthesis has been reported on the mortality rates after minor lower extremity amputation; thus, a quantitative evidence synthesis was needed.

METHODS

A systematic literature search was performed to identify studies that had reported the survival or mortality rates after a minor LEA. The studies were required to include one or more of the following primary outcomes: mortality rate at 30 days, 1 year, 3 years, 5 years, 6 to 7 years, or 8 to 9 years. The secondary outcomes were the mortality rates according to the anatomic location of the amputation in the foot and the independent risk factors for mortality.

RESULTS

A total of 28 studies with 17,325 subjects fulfilled the inclusion criteria. The meta-analytical results of the mortality rates were as follows: 3.5% at 1 month, 20% at 1 year, 28% at 3 years, 44.1% at 5 years, 51.3% at 6 to 7 years, and 58.5% at 8 to 9 years. From these studies of diabetic patients, age was the most consistent independent risk factor, followed by chronic kidney disease, PAD, and coronary artery disease. One study of patients with PAD had reported diabetes as an independent risk factor for mortality. The subgroup analysis of the four studies reporting the outcomes of patients with PAD showed greater 3- and 5-year mortality rates compared with the overall and "diabetic" results.

CONCLUSIONS

Mortality after minor amputation for patients with diabetes and/or PAD was found to be very high. Compared with the reported cancer data, survival was worse than that for many cancers. Just as in the case of major amputations, minor amputations should be considered a pivotal event in the life of these patients.

The role of Sudoscan feet asymmetry in the diabetic foot

The aim of this study was to investigate the role of Sudoscan asymmetry parameters in the diabetic foot.

PATIENTS AND METHODS

In this study we included 165 participants: 84 type 2 diabetes patients divided into three HbA1c matched groups - group 1: newly diagnosed diabetics (n = 31), group 2: people with longer diabetes duration and established neuropathy (n = 33), group 3: patients with diabetic foot ulcer (n = 20), and a control group of 81 people with prediabetes. All subjects underwent peripheral sudomotor evaluation using Sudoscan device (Impeto Medical, Paris).

RESULTS

Patients with diabetic foot had significantly higher Sudoscan feet asymmetry (19.6%) compared to those with only diabetic neuropathy (7.9%), compared to the group with newly diagnosed diabetes (7.44%), and compared to controls (2.5%). This test has shown a good discriminative value (with a threshold of 9.5%) for diabetic foot with area under the ROC curve of 0.955 (p = 0.001). Additionally, in a regression model feet asymmetry proved its predictive value for participants with diabetic foot.

CONCLUSION

In this study Sudoscan feet asymmetry proved to be a novel discriminator and predictor for diabetic foot patients. It might be considered as a marker for early damage in the neuropathy evaluation protocol.

Concordance in diabetic foot ulceration: a cross-sectional study of agreement between wound swabbing and tissue sampling in infected ulcers

BACKGROUND

There is inadequate evidence to advise clinicians on the relative merits of swabbing versus tissue sampling of infected diabetic foot ulcers (DFUs).

OBJECTIVES

To determine (1) concordance between culture results from wound swabs and tissue samples from the same ulcer; (2) whether or not differences in bacterial profiles from swabs and tissue samples are clinically relevant; (3) concordance between results from conventional culture versus polymerase chain reaction (PCR); and (4) prognosis for patients with an infected DFU at 12 months' follow-up.

METHODS

This was a cross-sectional, multicentre study involving patients with diabetes and a foot ulcer that was deemed to be infected by their clinician. Microbiology specimens for culture were taken contemporaneously by swab and by tissue sampling from the same wound. In a substudy, specimens were also processed by PCR. A virtual 'blinded' clinical review compared the appropriateness of patients' initial antibiotic regimens based on the results of swab and tissue specimens. Patients' case notes were reviewed at 12 months to assess prognosis.

RESULTS

The main study recruited 400 patients, with 247 patients in the clinical review. There were 12 patients in the PCR study and 299 patients in the prognosis study. Patients' median age was 63 years (range 26-99 years), their diabetes duration was 15 years (range 2 weeks-57 years), and their index ulcer duration was 1.8 months (range 3 days-12 years). Half of the ulcers were neuropathic and the remainder were ischaemic/neuroischaemic. Tissue results reported more than one pathogen in significantly more specimens than swabs {86.1% vs. 70.1% of patients, 15.9% difference [95% confidence interval (CI) 11.8% to 20.1%], McNemar's p-value < 0.0001}. The two sampling techniques reported a difference in the identity of pathogens for 58% of patients. The number of pathogens differed in 50.4% of patients. In the clinical review study, clinicians agreed on the need for a change in therapy for 73.3% of patients (considering swab and tissue results separately), but significantly more tissue than swab samples required a change in therapy. Compared with traditional culture, the PCR technique reported additional pathogens for both swab and tissue samples in six (50%) patients and reported the same pathogens in four (33.3%) patients and different pathogens in two (16.7%) patients. The estimated healing rate was 44.5% (95% CI 38.9% to 50.1%). At 12 months post sampling, 45 (15.1%) patients had died, 52 (17.4%) patients had a lower-extremity ipsilateral amputation and 18 (6.0%) patients had revascularisation surgery.

LIMITATIONS

We did not investigate the potential impact of microbiological information on care. We cannot determine if the improved information yield from tissue sampling is attributable to sample collection, sample handling, processing or reporting.

CONCLUSIONS

Tissue sampling reported both more pathogens and more organisms overall than swabbing. Both techniques missed some organisms, with tissue sampling missing fewer than swabbing. Results from tissue sampling more frequently led to a (virtual) recommended change in therapy. Long-term prognosis for patients with an infected foot ulcer was poor.

FUTURE WORK

Research is needed to determine the effect of sampling/processing techniques on clinical outcomes and antibiotic stewardship.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Diagnostic capability of retinal thickness measures in diabetic peripheral neuropathy

PURPOSE

To examine the diagnostic capability of the full retinal and inner retinal thickness measures in differentiating individuals with diabetic peripheral neuropathy (DPN) from those without neuropathy and non-diabetic controls.

METHODS

Individuals with (n=44) and without (n=107) diabetic neuropathy and non-diabetic control (n=42) participants underwent spectral domain optical coherence tomography (SDOCT). Retinal thickness in the central 1mm zone (including the fovea), parafovea and perifovea was assessed in addition to ganglion cell complex (GCC) global loss volume (GCC GLV) and focal loss volume (GCC FLV), and retinal nerve fiber layer (RNFL) thickness. Diabetic neuropathy was defined using a modified neuropathy disability score (NDS) recorded on a 0-10 scale, wherein, NDS ≥3 indicated neuropathy and NDS indicated <3 no neuropathy. Diagnostic performance was assessed by areas under the receiver operating characteristic curves (AUCs), 95 per cent confidence intervals (CI), sensitivities at fixed specificities, positive likelihood ratio (+LR), negative likelihood ratio (-LR) and the cut-off points for the best AUCs obtained.

RESULTS

The AUC for GCC FLV was 0.732 (95% CI: 0.624-0.840, p<0.001) with a sensitivity of 53% and specificity of 80% for differentiating DPN from controls. Evaluation of the LRs showed that GCC FLV was associated with only small effects on the post-test probability of the disease. The cut-off point calculated using the Youden index was 0.48% (67% sensitivity and 73% specificity) for GCC FLV. For distinguishing those with neuropathy from those without neuropathy, the AUCs of retinal parameters ranged from 0.508 for the central zone to 0.690 for the inferior RNFL thickness. For distinguishing those with moderate or advanced neuropathy from those with mild or no neuropathy, the inferior RNFL thickness demonstrated the highest AUC of 0.820, (95% CI: 0.731-0.909, p<0.001) with a sensitivity of 69% and 80% specificity. The cut-off-point for the inferior RNFL thickness was 97μm, with 81% sensitivity and 72% specificity.

CONCLUSIONS

The GCC FLV can differentiate individuals with diabetic neuropathy from healthy controls, while the inferior RNFL thickness is able to differentiate those with greater degrees of neuropathy from those with mild or no neuropathy, both with an acceptable level of accuracy. Optical coherence tomography represents a non-invasive technology that aids in detection of retinal structural changes in patients with established diabetic neuropathy. Further refinement of the technique and the analytical approaches may be required to identify patients with minimal neuropathy.

Incidence of lower extremity amputations in the diabetic compared with the non-diabetic population: A systematic review

Lower extremity amputation (LEA) in patients with diabetes results in high mortality, reduced quality of life, and increased medical costs. Exact data on incidences of LEA in diabetic and non-diabetic patients are important for improvements in preventative diabetic foot care, avoidance of fatal outcomes, as well as a solid basis for health policy and the economy. However, published data are conflicting, underlining the necessity for the present systematic review of population-based studies on incidence, relative risks and changes of amputation rates over time. It was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Nineteen out of 1582 studies retrieved were included in the analysis. The incidence of LEA in the diabetic population ranged from 78 to 704 per 100,000 person-years and the relative risks between diabetic and non-diabetic patients varied between 7.4 and 41.3. Study designs, statistical methods, definitions of major and minor amputations, as well as the methods to identify patients with diabetes differed greatly, explaining in part these considerable differences. Some studies found a decrease in incidence of LEA as well as relative risks over time. This obvious lack of evidence should be overcome by new studies using a standardized design with comparable methods and definitions.

Podiatry impact on high-low amputation ratio characteristics: A 16-year retrospective study

PURPOSE

Complications from diabetes mellitus including major lower extremity amputation may have significant impact on a patient's mortality. This study determined what impact the addition of a limb salvage and diabetic foot program involving podiatry had at an academic institution over 16years by analyzing high-low amputation ratio data.

METHODS

The high-low amputation ratio in the diabetic population who underwent non-traumatic amputation of the lower extremity was retrospectively evaluated at an academic institution via cohort discovery of the electronic medical record and analysis of billing over 16years.

RESULTS

We directly compared two eras, one without podiatry and one with a podiatry presence. It was found that with the addition of a podiatry program, limb salvage rates significantly increased (R² (without podiatry)=0.45, R² (with podiatry)=0.26), with a significant change in both the rate of limb salvage per year (-0.11% per year versus -0.36% per year; p<0.01) and an overall decrease in high-low amputation ratio (0.89 without podiatry to 0.60 with podiatry). Of note, approximately 40 major lower extremity amputations were avoided per year with the addition of a podiatry program (p<0.05).

CONCLUSIONS

Our findings signify the importance of podiatric care in the diabetic population. With an established podiatry program present at an academic institution, major lower extremity amputations can be avoided and more limbs can be salvaged, thus preventing some of the moribund complications from this condition.

Cardiac Autonomic Neuropathy in Patients with Type 2 Diabetes Mellitus at High Risk for Foot Ulcers

AIM

To study the prevalence of cardiac autonomic neuropathy (CAN) in patients with Type 2 diabetes mellitus at high risk for foot ulcers.

MATERIALS AND METHODS

We screened patients attending diabetic clinic for identifying patients at high risk for foot ulcers. Those with foot risk category 1, 2 and 3 as per criteria of Foot Care Interest Group were subjected to battery of cardiovascular autonomic reflex tests. Those with one abnormal test were termed as probable CAN and those with two abnormal tests as definite CAN. Those with postural fall in blood pressure with one other abnormal test were termed to have advanced CAN.

RESULTS

A total of 74 patients were recruited in the study. The prevalence of abnormal cardiovascular autonomic reflex test was sustained hand grip 81%, E/I ratio 66.2%, 30:15 ratio 28.3% and orthostatic hypotension 13.5%. The prevalence of possible CAN was 31.0% (23/74) and definite CAN was 66.2% (49/74). Ten patients had advanced CAN. There was no observable difference in presence of probable or definite CAN in three risk category for foot ulcers.

CONCLUSION

We found a high prevalence of CAN in subgroup of diabetic patients at increased risk for foot ulcer.

Interdisciplinary treatment of diabetic foot wounds in the elderly: Low risk of amputations and mortality and good chance of being mobile with good quality of life

AIMS

A major proportion of patients with diabetic foot syndrome are older than 65 years. Little is known about outcomes of these elderly patients.

METHODS

We analysed 245 treatment cases in an observational single-centre study for comorbidities and outcomes over a 6-month period.

RESULTS

In all, 122 patients had peripheral arterial disease which was significantly increasing with age (n = 245, df = 1, χ² = 23.06, p ⩽ 0.0001). Increasing age correlated positively with decreasing rate of revascularisations (n = 122, df = 1, χ² = 4.23, p = 0.039). In total, 23 (9.3%) patients died in the observation period. In-hospital mortality was 2.8%, percentage of major amputations 2.8%. In the invasively treated subgroup, 13 out of 67 patients died within the observation period. Death after revascularisation was independent of age (n = 67, df = 1, χ² = 2.05, p = 0.153). Mobility decreased in the whole study group with increasing age. The risk of decrease with age was not influenced by revascularisation status.

CONCLUSION

With careful interdisciplinary evaluation, elderly patients with diabetic foot syndrome can be treated with favourable outcome. Mobility before and after treatment deserves more attention as a predictor of treatment success and outcome parameter.

The amputation prevention initiative

BACKGROUND

The Amputation Prevention Initiative is a project conducted jointly by the Massachusetts Public Health Association and the Massachusetts Podiatric Medical Society that seeks to study methods to reduce nontraumatic lower-extremity amputations from diabetes.

METHODS

To determine the rate of diabetes-related lower-extremity amputations in Massachusetts and identify the groups most at risk, hospital billing and discharge data were analyzed. To examine the components of the diabetic foot examination routinely performed by general practitioners, surveys were conducted in conjunction with physician meetings in Massachusetts (n = 149) and in six other states (n = 490).

RESULTS

The average age-adjusted number of diabetes-related lower-extremity amputations in 2004 was 30.8 per 100,000 and 5.3 per 1,000 diabetic patients in MA, with high-risk groups being identified as men and black individuals. Among the general practitioners surveyed in Massachusetts, only 2.01% reported routinely conducting all four key components of the diabetic foot examination, with 28.86% reporting not performing any components.

CONCLUSIONS

These findings suggest that many general practitioners may be failing to perform the major components of the diabetic foot examination believed to prevent foot ulcers and lower-extremity amputations.

Diabetes-related lower extremity amputations in Singapore

Background:

Lower extremity amputation (LEA) is defined as the complete loss in the transverse anatomical plane of any part of the lower limb. The objective of this study is to look at the trend and mortality trend of LEA performed in diabetes patients from 2008 to 2013.

Methods:

All patients age 15 and above with diabetes mellitus who had undergone LEAs (both major and minor) in Tan Tock Seng Hospital, Singapore from 1 January 2008 to 31 December 2013 were included. The outcomes of interest were deaths from all causes within 30 days and within 1 year.

Results:

Major LEA rate has increased from 11.0 per 100,000 population in 2008 to 13.3 per 100,000 population in 2013. The 30-day mortality rate ranges from 6.0% to 11.1% and the 1-year mortality rate ranges from 24.3% to 30.6%. Minor LEA rate has increased from 10.8 per 100,000 population in 2008 to 13.9 per 100,000 population in 2013. The 30-day mortality rate ranges from 1.5% to 3.7% and the 1-year mortality rate ranges from 9.7% to 18.3%.

Conclusions:

The trends in major and minor LEA are increasing. The 30-day and 1-year mortality for both major and minor LEA are comparable to figures reported worldwide. There is a need to re-look at preventive strategies to reduce LEA in diabetes patients in Singapore.

Clinico-microbiological study and antibiotic resistance profile of mecA and ESBL gene prevalence in patients with diabetic foot infections

Diabetic foot infections (DFIs) constitute a major complication of diabetes mellitus. DFIs contribute to the development of gangrene and non-traumatic lower extremity amputations with a lifetime risk of up to 25%. The aim of the present study was to identify the presence of neuropathy and determine the ulcer grade, microbial profile and phenotypic and genotypic prevalence of the methicillin-resistance gene mecA and extended spectrum β-lactamase (ESBL)-encoding genes in bacterial isolates of DFI in patients registered at the Pakistan Institute of Medical Sciences (Islamabad, Pakistan). The results indicated that 46/50 patients (92%), exhibited sensory neuropathy. The most common isolate was Staphylococcus aureus (25%), followed by Pseudomonas aeruginosa (P. aeruginosa; 18.18%), Escherichia coli (16.16%), Streptococcus species (spp.) (15.15%), Proteus spp. (15.15%), Enterococcus spp. (9%) and Klebsiella pneumoniae (K. pneumoniae; 3%). The prevalence of the mecA gene was found to be 88% phenotypically and 84% genotypically. K. pneumoniae was shown to have the highest percentage of ESBL producers with a prevalence of 66.7% by double disk synergy test, and 100% by the cefotaxime + clavulanic acid/ceftazidime + clavulanic acid combination disk test. P. aeruginosa and K. pneumoniae had the highest (100%) proportion of metallo β-lactamase producers as identified by the EDTA combination disk test. The overall prevalence of β-lactamase (bla)-CTX-M, bla-CTX-M-15, bla-TEM, bla-OXA and bla-SHV genes was found to be 76.9, 76.9, 75.0, 57.7 and 84.6%, respectively, in gram-negative DFI isolates. The prevalence of mecA and ESBL-related genes was found to be alarmingly high in DFIs, since these genes are a major cause of antibiotic treatment failure.

Retinal Tissue Thickness is Reduced in Diabetic Peripheral Neuropathy

AIM

To investigate the relationship between diabetic peripheral neuropathy (DPN) and retinal tissue thickness.

METHODS

Full retinal thickness in the central retinal, parafoveal, and perifoveal zones and thickness of the ganglion cell complex and retinal nerve fiber layer (RNFL) were assessed in 193 individuals (84 with type 1 diabetes, 67 with type 2 diabetes, and 42 healthy controls) using spectral domain optical coherence tomography. Among those with diabetes, 44 had neuropathy defined using a modified neuropathy disability score recorded on a 0-10 scale. Multiple regression analysis was performed to investigate the relationship between diabetic neuropathy and retinal tissue thickness, adjusted for the presence of diabetic retinopathy (DR), age, sex, duration of diabetes, and HbA_1c levels.

RESULTS

In individuals with diabetes, perifoveal thickness was inversely related to the severity of neuropathy (p < 0.05), when adjusted for age, sex, duration of diabetes, and HbA_1c levels. DR was associated with reduced thickness in parafovea (p < 0.01). The RNFL was thinner in individuals with greater degrees of neuropathy (p < 0.04).

CONCLUSIONS

DPN is associated with structural compromise involving several retinal layers. This compromise may represent a threat to visual integrity and therefore warrants examination of functional correlates.

Mortality After Nontraumatic Major Amputation Among Patients With Diabetes and Peripheral Vascular Disease: A Systematic Review

High mortality rates have been reported after major amputations of a lower limb secondary to diabetes and peripheral vascular disease. However, the mortality rates have varied across studies. A systematic review of the 5-year mortality after nontraumatic major amputations of the lower extremity was conducted. A data search was performed of Medline using OVID, CINHAL, and Cochrane, 365 abstracts were screened, and 79 full text articles were assessed for eligibility. After review, 31 studies met the inclusion and exclusion criteria. Overall, the 5-year mortality rate was very high among patients with any amputation (major and minor combined), ranging from 53% to 100%, and in patients with major amputations, ranging from 52% to 80%. Mortality after below-the-knee amputation ranged from 40% to 82% and after above-the-knee amputation from 40% to 90%. The risk factors for increased mortality included age, renal disease, proximal amputation, and peripheral vascular disease. Although our previous systematic review of the 5-year mortality after ulceration had much lower rates of death, additional studies are warranted to determine whether amputation hastens death or is a marker for underlying disease severity.

Heart rate-corrected QT interval prolongation as a prognostic marker for 3-year survival in people with Type 2 diabetes undergoing above-ankle amputation

AIM

To evaluate whether heart rate-corrected QT interval is a plausible prognostic factor for survival after major amputation in people with Type 2 diabetes.

METHODS

All people with Type 2 diabetes aged < 80 years who underwent a major amputation at two hospitals with multidisciplinary diabetic foot teams were evaluated and grouped according to whether their heart rate-corrected QT interval was  ≤  or  > 440 ms.

RESULTS

A total of 70 patients with a median age of 72 years were included in the study. During the 3 years of follow-up, 38 patients (54%) died. Heart rate-corrected QT interval prolongation was present in 51.4% of the patients and was strongly associated with 3-year mortality (73 vs 36%; P < 0.001). In a Cox proportional hazard model, heart rate-corrected QT interval prolongation was the strongest independent risk factor for 3-year mortality [hazard ratio 2.20 (95% CI 1.11-4.38)]. Treatment with metformin seemed to have a protective effect [hazard ratio 0.22 (95% CI 0.05-0.94)].

CONCLUSIONS

The findings of the present study indicate that heart rate-corrected QT interval prolongation is associated with increased mortality in people with Type 2 diabetes undergoing above-ankle amputation.

Impairment of Wound Healing in Patients With Type 2 Diabetes Mellitus Influences Circulating MicroRNA Patterns via Inflammatory Cytokines

OBJECTIVE

MicroRNAs (miRNA/miR) are stably present in body fluids and are increasingly explored as disease biomarkers. Here, we investigated influence of impaired wound healing on the plasma miRNA signature and their functional importance in patients with type 2 diabetes mellitus.

APPROACH AND RESULTS

miRNA array profiling identified 41 miRNAs significantly deregulated in diabetic controls when compared with patients with diabetes mellitus-associated peripheral arterial disease and chronic wounds. Quantitative real-time polymerase chain reaction validation confirmed decrease in circulating miR-191 and miR-200b levels in type 2 diabetic versus healthy controls. This was reverted in diabetic subjects with associated peripheral arterial disease and chronic wounds, who also exhibited higher circulating C-reactive protein and proinflammatory cytokine levels compared with diabetic controls. miR-191 and miR-200b were significantly correlated with C-reactive protein or cytokine levels in patients with diabetes mellitus. Indeed, proinflammatory stress increased endothelial- or platelet-derived secretion of miR-191 or miR-200b. In addition, dermal cells took up endothelial-derived miR-191 leading to downregulation of the miR-191 target zonula occludens-1. Altered miR-191 expression influenced angiogenesis and migratory capacities of diabetic dermal endothelial cells or fibroblasts, respectively, partly via its target zonula occludens-1.

CONCLUSIONS

This study reports that (1) inflammation underlying nonhealing wounds in patients with type 2 diabetes mellitus influences plasma miRNA concentrations and (2) miR-191 modulates cellular migration and angiogenesis via paracrine regulation of zonula occludens-1 to delay the tissue repair process.

The impact of foot ulceration and amputation on mortality in diabetic patients. I: From ulceration to death, a systematic review

A great deal of emphasis, clinical and financial, is placed on limb salvage efforts in diabetic patients suffering from lower extremity ulceration. This is because of the impression that amputation in such patients may be a proximal cause of death. While amputation is certainly a negative clinical outcome, it is not entirely clear that it causes death. In this systematic review, we examine the available literature to attempt to understand the role that the ulceration itself may play in mortality. In brief, we searched for human studies in OVID, CINAHL and the COCHRANE CENTRAL DATABASE from 1980 to 2013, looking for articles related to ulcer or wound of the foot, in patients with diabetes or peripheral vascular disease, and death. We looked for articles with 5 years of follow-up, or Kaplan-Meier estimates of 5-year mortality, and excluded reviews and letters. Articles were assessed for quality and potential bias using the Newcastle-Ottawa scale. We find that while the patient populations studied varied widely in terms of demographics and comorbidities, limiting generalisability, 5-year mortality rates after ulceration were around 40%. Risk factors for death commonly identified were increased age, male gender, peripheral vascular disease and renal disease.

Mesenchymal stem cells: potential for therapy and treatment of chronic non-healing skin wounds

Wound healing is a complex physiological process including overlapping phases (hemostatic/inflammatory, proliferating and remodeling phases). Every alteration in this mechanism might lead to pathological conditions of different medical relevance. Treatments for chronic non-healing wounds are expensive because reiterative treatments are needed. Regenerative medicine and in particular mesenchymal stem cells approach is emerging as new potential clinical application in wound healing. In the past decades, advance in the understanding of molecular mechanisms underlying wound healing process has led to extensive topical administration of growth factors as part of wound care. Currently, no definitive treatment is available and the research on optimal wound care depends upon the efficacy and cost-benefit of emerging therapies. Here we provide an overview on the novel approaches through stem cell therapy to improve cutaneous wound healing, with a focus on diabetic wounds and Systemic Sclerosis-associated ulcers, which are particularly challenging. Current and future treatment approaches are discussed with an emphasis on recent advances.

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.

Cognitive functioning among patients with diabetic foot

AIMS

Using diabetic foot (DF) as an indicator of severe diabetes, we aimed to investigate the cognitive profile of DF patients and the relations between cognitive functioning and both diabetes complications and comorbidities.

METHODS

Dementia-free patients with DF aged 30-90 (n=153) were assessed through medical records and a cognitive battery. Information on diabetes complications and comorbidities was collected via interview; glycated hemoglobin (HbA1c) was tested. Data were analyzed using robust logistic or quantile regression adjusted for potential confounders.

RESULTS

The mean Mini-Mental Examination (MMSE) score of patients was 24.6 (SD=3.6), and 40% had global cognitive dysfunction (MMSE ≤24). Among elderly patients (aged ≥65), MMSE impairment was related to amputation (OR 3.59, 95% CI 1.07-12.11). Episodic memory impairment was associated with foot amputation (OR 4.13, 95% CI 1.11-15.28) and microvascular complications (OR 9.68, 95% CI 1.67-56.06). Further, elderly patients with HbA1c <7% had increased odds of psychomotor slowness (OR 7.75, 95% CI 1.55-38.73) and abstract reasoning impairment (OR 4.49, 95% CI: 1.15-17.46). However, such significant associations were not shown in adult patients aged <65.

CONCLUSION

Amputation, microvascular diseases and glycemic control were associated with impaired global cognitive function and its domains among patients aged ≥65.

Newly diagnosed diabetes mellitus after acute pancreatitis: a systematic review and meta-analysis

BACKGROUND

Diabetes mellitus (DM) is common in the general population and it poses a heavy burden to society in the form of long-term disability, healthcare use and costs. The pancreas is a key player in glucose homeostasis, but the occurrence of newly diagnosed DM after acute pancreatitis (AP), the most frequent disease of the pancreas, has never been assessed systematically. The aim of this study was to conduct a systematic literature review to determine the prevalence and time course of DM and related conditions after the first attack of AP as well as the impact of covariates.

METHODS

Relevant literature cited in three electronic databases (Scopus, EMBASE and MEDLINE) was reviewed independently by two authors. The main outcome measures studied were newly diagnosed prediabetes, DM, or DM treated with insulin. Pooled prevalence and 95% CIs were calculated for all outcomes.

RESULTS

A total of 24 prospective clinical studies, involving 1102 patients with first episode of AP, met all the eligibility criteria. Prediabetes and/or DM was observed in 37% (95% CI 30% to 45%) individuals after AP. The pooled prevalence of prediabetes, DM and treatment with insulin after AP was 16% (95% CI 9% to 24%), 23% (95% CI 16% to 31%), and 15% (95% CI 9% to 21%), respectively. Newly diagnosed DM developed in 15% of individuals within 12 months after first episode of AP and the risk increased significantly at 5 years (relative risk 2.7 (95% CI 1.9 to 3.8)). A similar trend was observed with regard to treatment with insulin. The severity of AP, its aetiology, individuals' age and gender had minimal effect on the studied outcomes.

CONCLUSIONS

Patients with AP often develop prediabetes and/or DM after discharge from hospital, and have a greater than twofold increased risk of DM over 5 years. Further studies are warranted to determine the optimal strategy for its detection and whether the risk of developing DM after AP can be reduced.

Decellularized silk fibroin scaffold primed with adipose mesenchymal stromal cells improves wound healing in diabetic mice

INTRODUCTION

Silk fibroin (SF) scaffolds have been shown to be a suitable substrate for tissue engineering and to improve tissue regeneration when cellularized with mesenchymal stromal cells (MSCs). We here demonstrate, for the first time, that electrospun nanofibrous SF patches cellularized with human adipose-derived MSCs (Ad-MSCs-SF), or decellularized (D-Ad-MSCs-SF), are effective in the treatment of skin wounds, improving skin regeneration in db/db diabetic mice.

METHODS

The conformational and structural analyses of SF and D-Ad-MSCs-SF patches were performed by scanning electron microscopy, confocal microscopy, Fourier transform infrared spectroscopy and differential scanning calorimetry. Wounds were performed by a 5 mm punch biopsy tool on the mouse's back. Ad-MSCs-SF and D-Ad-MSCs-SF patches were transplanted and the efficacy of treatments was assessed by measuring the wound closure area, by histological examination and by gene expression profile. We further investigated the in vitro angiogenic properties of Ad-MSCs-SF and D-Ad-MSCs-SF patches by affecting migration of human umbilical vein endothelial cells (HUVECs), keratinocytes (KCs) and dermal fibroblasts (DFs), through the aortic ring assay and, finally, by evaluating the release of angiogenic factors.

RESULTS

We found that Ad-MSCs adhere and grow on SF, maintaining their phenotypic mesenchymal profile and differentiation capacity. Conformational and structural analyses on SF and D-Ad-MSCs-SF samples, showed that sterilization, decellularization, freezing and storing did not affect the SF structure. When grafted in wounds of diabetic mice, both Ad-MSCs-SF and D-Ad-MSCs-SF significantly improved tissue regeneration, reducing the wound area respectively by 40% and 35%, within three days, completing the process in around 10 days compared to 15-17 days of controls. RT2 gene profile analysis of the wounds treated with Ad-MSCs-SF and D-Ad-MSCs-SF showed an increment of genes involved in angiogenesis and matrix remodeling. Finally, Ad-MSCs-SF and D-Ad-MSCs-SF co-cultured with HUVECs, DFs and KCs, preferentially enhanced the HUVECs' migration and the release of angiogenic factors stimulating microvessel outgrowth in the aortic ring assay.

CONCLUSIONS

Our results highlight for the first time that D-Ad-MSCs-SF patches are almost as effective as Ad-MSCs-SF patches in the treatment of diabetic wounds, acting through a complex mechanism that involves stimulation of angiogenesis. Our data suggest a potential use of D-Ad-MSCs-SF patches in chronic diabetic ulcers in humans.

Elevated serum uric acid levels are independent risk factors for diabetic foot ulcer in female Chinese patients with type 2 diabetes

BACKGROUND

To investigate the relationship between elevated serum uric acid levels and the presence of diabetic foot ulcer (DFU) in Chinese patients with type 2 diabetes (T2D).

METHODS

A retrospective study was performed on 829 outpatients with T2D (478 men, 351 women) who visited the Diabetes Clinic (Nanfang Hospital, Southern Medical University) from January 2007 to December 2009. Information regarding their clinical history, anthropometric measurements, and laboratory data were collected. Potential confounding variables with P < 0.10 were adjusted for in multivariate logistic regression analysis.

RESULTS

In univariate analyses, there was a significant difference in serum uric acid levels between female patients with and without DFU (370 ± 128 vs. 313 ± 107 μmol/L, respectively; P < 0.05), but not between male patients with and without DFU (317 ± 100 vs. 348 ± 111 μmol/L, respectively; P = 0.643). The prevalence of DFU among quintiles of uric acid levels (from 1-20% to 80-100%) was 5.3%, 3.9%, 7.7%, 5.5%, and 16.7%, respectively. Using uric acid level as a continuous variable, the multivariate-adjusted odds ratio for diabetic foot ulcer in female patients was 1.004 (95% confidence interval 1.001-1.008; P < 0.05).

CONCLUSIONS

Elevated uric acid levels are a significant and independent risk factor for diabetic foot ulcer in female Chinese patients with T2D. Whether serum uric acid is involved in the pathogenesis of DFU in female patients remains to be investigated.

Incidence of repeat amputation after partial first ray amputation associated with diabetes mellitus and peripheral neuropathy: an 11-year review

The reliability and durability of partial first ray amputation in patients with diabetes and peripheral neuropathy has recently been questioned. In an effort to determine the repeat amputation rate after a partial first ray amputation associated with diabetes mellitus and peripheral neuropathy at our institution, we performed an 11-year retrospective review. A total of 59 patients (40 males and 19 females), with a mean age of 63 (range 39 to 97) years, were included. The mean follow-up was 33.8 (range 1 to 123) months, with initial incision healing occurring in all 59 patients. Despite the initial healing, 69% developed a mean of 3.1 subsequent foot ulcerations at a mean of 10.5 months, 36% required ancillary surgical procedures, and more than 90% of patients were prescribed multiple courses of antibiotics at a mean of 26.6 clinic visits during the follow-up period. A total of 25 patients (42.4%) underwent more proximal repeat amputation at a mean of 25 (range 1 to 97) months after the initial partial first ray amputation. The results of our retrospective review revealed that nearly 1 of every 2 patients with diabetes and peripheral neuropathy who undergo a partial first ray amputation will progress to a more proximal repeat amputation, despite initial healing. These data question the reliability and durability of this level of amputation as a primary procedure in this patient population. A more proximal level amputation, such as a balanced transmetatarsal, might provide a better functional and reliable residual weightbearing foot and should be considered at the initial presentation. This is especially true given that nearly one half of the patients died during the follow-up period. However, this remains a matter for conjecture because of the limited data available; therefore, additional prospective investigations are warranted.

Clinical utility of insulin and insulin analogs

Diabetes is a pandemic disease characterized by autoimmune, genetic and metabolic abnormalities. While insulin deficiency manifested as hyperglycemia is a common sequel of both Type-1 and Type-2 diabetes (T1DM and T2DM), it does not result from a single genetic defect--rather insulin deficiency results from the functional loss of pancreatic β cells due to multifactorial mechanisms. Since pancreatic β cells of patients with T1DM are destroyed by autoimmune reaction, these patients require daily insulin injections. Insulin resistance followed by β cell dysfunction and β cell loss is the characteristics of T2DM. Therefore, most patients with T2DM will require insulin treatment due to eventual loss of insulin secretion. Despite the evidence of early insulin treatment lowering macrovascular (coronary artery disease, peripheral arterial disease and stroke) and microvascular (diabetic nephropathy, neuropathy and retinopathy) complications of T2DM, controversy exists among physicians on how to initiate and intensify insulin therapy. The slow acting nature of regular human insulin makes its use ineffective in counteracting postprandial hyperglycemia. Instead, recombinant insulin analogs have been generated with a variable degree of specificity and action. Due to the metabolic variability among individuals, optimum blood glucose management is a formidable task to accomplish despite the presence of novel insulin analogs. In this article, we present a recent update on insulin analog structure and function with an overview of the evidence on the various insulin regimens clinically used to treat diabetes.

Nurses' role in diabetic foot prevention and care; a review

Diabetes as one of Non-communicable diseases has allocated a large proportion of cost, time and human resources of health systems. Now, due to changes in lifestyle and industrial process, incidence of diabetes and its complications have been increased. Accordingly diabetic foot considered as a common complication of diabetes.Nurses are health care providers who actively involved in prevention and early detection of diabetes and its complications. The nurses' role could be in health care, health, community education, health systems management, patient care and improving the quality of life.Diabetes Nurses play their educating role in the field of prevention of diabetic foot, foot care and preventing from foot injury. In care dimension, nurses responsible for early detection of any changes in skin and foot sensation, foot care, dressing and apply novel technology.In the area of rehabilitation, help patient sufferings from diabetic foot ulcer or amputation, to have movement are diabetes nurse's duties.Consequently, nurses need to attend in special training to use the latest instructions of diabetic foot care in order that provides the effective services to facilitate promote diabetic patients health.

Amputation rate and risk factors in type 2 patients with diabetic foot syndrome under real-life conditions in Germany

AIMS

To determine the risk of amputation and the influencing factors for amputation for patients with type 2 diabetes with diabetic foot syndrome.

METHODS

Longitudinal data from general practices in Germany (Disease Analyzer database, IMS Health) were analyzed. 3892 type 2 diabetes patients (mean age: 66.0 (SD: 10.9 years), 39.1% female) with a first-time diagnosis of diabetic foot syndrome between 01/200 and 12/2004 and at least 5 year follow-up documentation in the practices were included. The analyses of amputation-free survival were carried out using Kaplan-Meier curves and log-rank tests. A multivariate Cox regression model was fitted with the incident of diabetes-associated amputations as the dependent variable and adjusted for clinical and demographic characteristics.

RESULT

The cumulative incidence of diabetes-associated lower limb amputations was 18.2%. Amputations are independently associated with higher age, male gender, higher HbA1c value and longer diabetes duration but also some other diabetes complications.

DISCUSSION

The diabetic foot syndrome can but must not lead to a lower limb amputation. Due to the great medical and economic burden on the health system caused by diabetic complications, early therapeutic intervention is essential for patients with diabetic foot syndrome.

Autologous stem cell therapy in the treatment of limb ischaemia induced chronic tissue ulcers of diabetic foot patients

BACKGROUND AND AIM

Despite improvements in surgical revascularisation, limitations like anatomical factors or atherosclerosis limit the success of revascularisation in diabetic patients with critical limb ischaemia. Stem cells were shown to improve microcirculation in published studies. The aim of this study was to evaluate safety, feasibility and efficacy of transplantation of bone marrow derived cellular products regarding improvement in microcirculation and lowering of amputation rate.

METHODS

Bone marrow mononuclear cells (BMCs) in comparison with expanded bone marrow cells enriched in CD90+ cells ('tissue repair cells', TRCs) were used in the treatment of diabetic ulcers to induce revascularisation. Diabetic foot patients with critical limb ischaemia without option for surgical or interventional revascularisation were eligible. Parameters examined were ABI, TcPO(2) , reactive hyperaemia and angiographic imaging before and after therapy.

RESULTS

Of 30 patients included in this trial, 24 were randomised to receive either BMCs or TRCs. The high number of drop-outs in the control group (4 of 6) led to exclusion from evaluation. A total of 22 patients entered treatment; one patient in the TRC group and two in the BMC group did not show wound healing during follow up, one patient in each treatment group died before reaching the end of the study; one after having achieved wound healing (BMC group), the other one without having achieved wound healing (TRC group). Thus, 18 patients showed wound healing after 45 weeks. The total number of applicated cells was 3.8 times lower in the TRC group, but TRC patients received significantly higher amounts of CD90+ cells. Improvement in microvascularisation was detected in some, but not all patients by angiography, TcPO(2) improved significantly compared with baseline in both therapy groups.

CONCLUSION

The transplantation of BMCs as well as TRCs proved to be safe and feasible. Improvements of microcirculation and complete wound healing were observed in the transplant groups.