Amputations and mortality in in-hospital treated patients with peripheral artery disease and diabetic foot syndrome

Diabetic peripheral arterial disease in COVID-19 pandemic

Both diabetes and peripheral arterial disease (PAD) have complex interactions with COVID-19. PAD is one of the most important underlying factors in the development of diabetic foot. The COVID-19 pandemic has also caused an increase in cardiovascular complications in those with chronic diseases, including diabetics, due to both the thrombophilic course of the viral disease and the lockdown measures applied for prevention. Since both COVID-19 and diabetes mellitus predispose to thrombosis, PAD is likely to have a more severe course in diabetic patients with COVID-19. The aim of our study is to discuss the complications, prophylaxis, and treatment of PAD, which is a serious complication of diabetes, during the pandemic period.

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

CLINICAL IMPACT

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

Long-Term Outcome of Lower Extremity Bypass Surgery in Diabetic and Non-Diabetic Patients with Critical Limb-Threatening Ischaemia in Germany

AIM

To present the short- and long-term outcomes of lower extremity bypass (LEB) surgery in patients with critical limb-threatening ischaemia (CLTI), comparing diabetic (DM) and non-diabetic (non-DM) patients.

METHODS

Retrospective analysis of anonymised data from a nationwide health insurance company (AOK). Data from 22,633 patients (DM: n = 7266; non-DM: n = 15,367; men: n = 14,523; women: n = 8110; mean patient age: 72.5 years), who underwent LEB from 2010 to 2015, were analysed. The cut-off date for follow-up was December 31, 2018 (mean follow-up period: 55 months).

RESULTS

Perioperative mortality was 10.0% for DM and 8.2% for non-DM (p < 0.001). Patients with crural/pedal bypasses (n = 8558) had a significantly higher perioperative mortality (10.3%) than those with above-the-knee (n = 7246; 5.8%; p < 0.001) and below-the-knee bypasses (n = 6829; 8.9%; p = 0.003). The 9-year survival rates in DM patients were significantly worse, at 21.5%, compared to non-DM, at 31.1% (p < 0.001). This applied to both PAD stage III (DM: 34.4%; non-DM: 45.7%; p < 0.001) and PAD stage IV (DM: 18.5%; non-DM: 25.0%; p < 0.001). Patients with crural/pedal bypasses had a significantly inferior survival rate (25.5%) compared to those with below-the-knee (27.7%; p < 0.001) and above-the-knee bypasses (31.7%; p < 0.001).

CONCLUSION

Perioperative and long-term outcomes regarding survival and major amputation rate for CLTI patients undergoing LEB are consistently worse for DM patients compared to non-DM patients.

Analysis of Lower Extremity Amputations from the SerbVasc Registry

BACKGROUND

Peripheral arterial disease (PAD) and diabetes are the major causes of lower extremity amputations (LEAs) worldwide. Morbidity and mortality in patients with LEAs are high with an associated significant burden on the global health system. The aim of this article is to report the overall morbidity and mortality rates after major and minor LEAs from the Serbian Vascular Registry (SerbVasc), with an analysis of predictive factors that influenced adverse outcomes.

MATERIALS AND METHODS

SerbVasc was created in 2019 as a part of the Vascunet collaboration that is aiming to include all vascular procedures from 21 hospitals in Serbia. Prevalence of diabetes among patients with LEAs, previous revascularization procedures, the degree and the type of foot infection and tissue loss, and overall morbidity and mortality rates were analyzed, with a special reference to mortality predictors.

RESULTS

In the period from January 2020 to December 2022, data on 702 patients with LEAs were extracted from the SerbVasc registry, mean age of 69.06±10.63 years. Major LEAs were performed in 59%, while minor LEAs in 41% of patients. Diabetes was seen in 65.1% of the patients, with 44% of them being on insulin therapy. Before LEA, only 20.3% of patients had previous peripheral revascularization. Soft tissue infection, irreversible acute ischemia, and Fontaine III and IV grade ischemia were the most common causes of above-the-knee amputations while diabetic foot was the most common cause of transphalangeal and toe amputations. The infection rate was 3.7%, the re-amputation rate was 5.7%, and the overall mortality rate was 6.9%, with intrahospital mortality in patients with above-the-knee amputation of 11.1%. The most significant intrahospital mortality predictors were age >65 years (p<0.001), chronic kidney disease (CKD) (p<0.001), ischemic heart disease (IHD) (p=0.001), previous myocardial revascularization (p=0.017), emergency type of admission (p<0.001), not using aspirin (p=0.041), using previous anticoagulation therapy (p=0.003), and postoperative complications (p<0.001).

CONCLUSIONS

The main predictors of increased mortality after LEAs from the SerbVasc registry are age >65 years, CKD, IHD, previous myocardial revascularization, emergency type of admission, not using aspirin, using previous anticoagulation therapy, and postoperative complications. Taking into account high mortality rates after LEAs and a small proportion of previous peripheral revascularization, the work should be done on early diagnosis and timely treatment of PAD hopefully leading to decreased number of LEAs and overall mortality.

CLINICAL IMPACT

Mortality after lower limb amputation from the SerbVasc register is high. A small number of previously revascularized patients is of particular clinical importance, bearing in mind that the main reasons for above-the-knee amputations were irreversible ischemia, Fontaine III and Fontaine IV grade ischemia. Lack of diagnostics procedures and late recognition of patients with PAD, led to subsequent threating limb ischemia and increased amputation rates. The work should be done on early diagnosis and timely treatment of PAD in Serbia, hopefully leading to an increased number of PAD procedures, decreased number of LEAs, and lower overall mortality.

Inflammatory Markers Used as Predictors of Subclinical Atherosclerosis in Patients with Diabetic Polyneuropathy

BACKGROUND

peripheral arterial disease (PAD) is identified late in diabetic patients because, in the majority of cases, it is associated with diabetic peripheral neuropathy, resulting in little or no symptoms, or symptoms that are completely neglected.

METHODS

In this study were enrolled all patients over 18 years of age, with diabetes mellitus type II for more than a year with poor glycemic control, diagnosed with diabetic polyneuropathy admitted to the Diabetology Department, Emergency County Hospital of Targu Mures, Romania between January 2020 and March 2023. We divided the patients into two groups, based on the presence or absence of subclinical atherosclerosis in the lower limb, named "SA" and "non-SA".

RESULTS

Patients in the SA group were older (p = 0.01) and had a higher incidence of IHD (p = 0.03), history of MI (p = 0.02), and diabetic nephropathy (p = 0.01). Moreover, patients with subclinical atherosclerosis had a higher BMI (p < 0.0001) and a longer duration of diabetes (p < 0.0001). Among all patients, the systemic inflammatory markers, MLR (r = 0.331, p < 0.001), NLR (r = 0.517, p < 0.001), PLR (r = 0.296, p < 0.001), SII (r = 0.413, p < 0.001), as well as BMI (r = 0.241, p < 0.001) and HbA1C (r = 0.489, p < 0.001), demonstrated a strong positive correlation with the diabetes duration. The multivariate logistic regression analysis showed that older patients (OR: 2.58, p < 0.001), the male gender (OR: 2.30, p = 0.006), a higher baseline levels of BMI (OR: 7.71, p < 0.001), and the duration of diabetes (OR: 8.65, p < 0.001) are predictors of subclinical atherosclerosis in DN patients. Additionally, the high baseline levels of all systemic inflammatory markers (for all: p < 0.001) and poor diabetes management (OR: 10.4, p < 0.001 for HbA1C; OR: 10.78, p < 0.001 for admission glucose) are independent predictors of SA.

CONCLUSIONS

the inflammatory markers, NLR, MLR, PLR, and SII, being cheap and easy to collect in routine medical practice from the standard blood tests, could be an important step in predicting vascular outcomes in diabetic patients and the disease's progression, playing a key role in follow-up visits in type-2 diabetic patients and PAD patients.

Revascularisation Options for Chronic Limb Threatening Ischaemia in Diabetes: Implications From Two Recent Trials

Chronic limb-threatening ischaemia (CLTI) is a severe form of peripheral arterial disease (PAD) and is associated with an increased risk of amputation, mortality, and significantly impaired quality of life. International guidelines recommend considering timely revascularisation and optimal medical therapy to improve limb perfusion in individuals with CLTI. The 2 primary revascularization approaches for CLTI are open bypass surgery (BS) and endovascular therapy (EV), however, there is currently no consensus on the best initial treatment strategy for CLTI, leading to uncertainty among clinicians. To shed light on this issue, 2 recent trials, namely best endovascular versus best surgical therapy in patients with CLI (BEST-CLI) and bypass versus angioplasty for severe ischaemia of the leg (BASIL-2), have tried to provide valuable insights. While a definitive conclusion on the optimal revascularisation approach is still pending, these trials offer immediate and clinically relevant information to the diabetic foot multidisciplinary team. The trials encompassed a distinct range of patient cohorts and included participants with varying degrees of medical and physical frailty. Taken together, their findings, highlight the need for an individualised revascularisation strategy which accounts for underlying comorbidities, risk factors, disease severity, availability of suitable bypass conduits, surgical risks, and timely access to procedures. Regardless of the chosen strategy, early referral of patients with diabetes and CLTI to a specialist team within a multidisciplinary environment is crucial. Comprehensive care should encompass essential elements such as adequate debridement, infection control, offloading, glycaemic control, smoking cessation, and patient education. By addressing these aspects, healthcare providers can optimise the management and outcomes for individuals with CLTI and diabetes.

Global mortality of diabetic foot ulcer: A systematic review and meta-analysis of observational studies

AIM

To estimate the long-term mortality and risk factors in patients with diabetic foot ulcer (DFU).

METHODS

We systematically searched Medline (PubMed), Embase, Scopus, Web of Science, Cochrane Library, China Science and Technology Journal Database (CQVIP), China National Knowledge Infrastructure, the Chinese Biomedical Literature Database (SinoMed) and Wanfang Data from 1 January 2011 to 31 July 2022. All observational studies that reported long-term mortality of patients with DFU were included. Random effect models were used to pool the reconstructed participant data from Kaplan-Meier curves. The primary outcome was the long-term survival of patients with DFU. An aggregate data meta-analysis was also performed.

RESULTS

We identified 34 studies, with 124 376 participants representing 16 countries, among whom there were 51 386 deaths. Of these, 27 studies with 21 171 patients were included in the Kaplan-Meier-based meta-analysis. The estimated Kaplan-Meier-based survival rates were 86.9% (95% confidence interval [CI] 82.6%-91.5%) at 1 year, 66.9% (95% CI 59.3%-75.6%) at 3 years, 50.9% (95% CI 42.0%-61.7%) at 5 years and 23.1% (95% CI 15.2%-34.9%) at 10 years. The results of the aggregate data-based meta-analysis were similar. Cardiovascular disease and infection were the most common causes of death, accounting for 46.6% (95% CI 33.5%-59.7%) and 24.8% (95% CI 16.0%-33.5%), respectively. Patients with older age (per 1 year, hazard ratio [HR] 1.054, 95% CI 1.045-1.063), peripheral artery disease (HR 1.882, 95% CI 1.592-2.225), chronic kidney disease (HR 1.535, 95% CI 1.227-1.919), end-stage renal disease (HR 3.586, 95% CI 1.333-9.643), amputation (HR 2.415, 95% CI 1.323-4.408) and history of cardiovascular disease (HR 1.449, 95% CI 1.276-1.645) had higher mortality risk.

CONCLUSIONS

This meta-analysis found that the overall mortality of DFU was high, with nearly 50% mortality within 5 years. Cardiovascular disease and infection were the two leading causes of death.

Weakness of lower limb muscle in symptomatic peripheral artery disease with media sclerosis detected by ultrasound shear wave elastography

Background: Symptomatic peripheral arterial disease (PAD) is difficult to non-invasively diagnose in the presence of calcified, media sclerotic arteries that are incompressible by blood pressure cuffs. Standard ankle-brachial index (ABI) measurements in these PAD patients are very often not helpful. Shear wave elastography (SWE) is a modern ultrasound technique to detect peripheral muscle stiffness changes i.e. muscle weakness during exercise. In a pilot study, we examined whether SWE could be a reproducible tool for diagnosing ischemic loss of muscle stiffness in patients with PAD and concomitant arterial media sclerosis. Patients and methods: N=13 consecutive patients with peripheral artery disease and media sclerosis were enrolled in the pilot study. All 13 patients were symptomatic in different stages of their PAD due to hemodynamically relevant arterial stenosis or occlusions of limb arteries as confirmed by oscillography, color-coded duplex sonography or angiography. Results: ABI measurements were invalid in all 13 patients. Mean SWE measurements of medial gastrocnemius muscles showed a significant transient muscle stiffness loss (weakness) at maximum exercise (active dorsal flexion of the foot, 103.4±25.9 kPa on the asymptomatic vs. 62.5±21.9 kPa on the symptomatic limb (p<0.001). Conclusions: SWE can reproducibly detect peripheral muscle weakness during exercise in the symptomatic leg of media sclerotic PAD patients. SWE of lower limb muscles may help to identify symptomatic PAD in patients presenting with invalid ABI measurements and unclear vascular status.

Safety and Effectiveness of Endovascular Therapy for the Treatment of Peripheral Artery Disease in Patients with and without Diabetes Mellitus

This study investigated the distribution of risk factors, lesion characteristics and endovascular revascularization (EVR) strategies in patients with peripheral arterial disease (PAD) with vs without diabetes mellitus (DM). Data were collected within the RECcording COurses of vasculaR Diseases (RECCORD) registry. Demographic data, lesion localization (iliac vs femoropopliteal vs below-the-knee (BTK)) and lesion complexity score (LCS) based on number of affected segments, and lesion length (< 10 vs 10-20 vs > 20 cm), EVR strategies and peri-procedural complications were analysed in 786 patients with and 1337 without diabetes mellitus. Patients with diabetes mellitus were older (71.6 ± 9.6 vs 69.4 ± 10.5 years, P < .001) and had higher LCS and more often BTK lesions (P < .05 for all). Lesions were treated less frequently with stents (48.7 vs 59.6%, P < .001) in patients with diabetes mellitus, whereas a non-significant trend was noticed for higher DCB treatment rates (48.3 vs 44.4%, P = .07). Post-interventional ankle-brachial index (ABI) increase was similar (from .77 ± .28 to .92 ± .25 with diabetes mellitus and from .74 ± .21 to .90 ± .20 without diabetes mellitus, P < .001 for both). Peri-/post-procedural complications were low in both groups (4.6%). Patients with diabetes mellitus, who undergo endovascular revascularization are older, have more comorbidities and higher target lesion complexity. However, treatment success rates are similar and complication rates are low.

Approaches to Peripheral Artery Disease in Diabetes: Are There Any Differences?

Peripheral artery disease (PAD) increases the risk of diabetes, while diabetes increases the risk of PAD, and certain symptoms in each disease increase the risk of contracting the other. This review aims to shed light on this harmful interplay between the two disorders, with an emphasis on the phenotype of a patient with both diabetes and PAD, and whether treatment should be individualized in this high-risk population. In addition, current guideline recommendations for the treatment of PAD were analyzed, in an attempt to establish the differences and evidence gaps across a population suffering from these two interconnected disorders.

Major Lower Limb Amputations and Amputees in an Aging Population in Southwest Finland 2007-2017

Purpose

The aim of the present study was to describe and analyze changes in the incidences of lower extremity amputations (LEAs), patient characteristics, vascular history of amputees and survival in Southwest Finland.

Patients and Methods

This is a retrospective patient study in the Hospital District of Southwest Finland. All consecutive patients with atherosclerosis and diabetes-caused LEA, between 1st January 2007 and 31st December 2017, were included. The annual incidences of major LEA patients were statistically standardized. Patients' diagnoses, functional status, previous revascularizations and minor amputations were recorded, and survival was analyzed.

Results

During the 11-year-period major LEAs were performed on 891 patients, 118 (13.2%) were urgent operations. The overall incidence of major LEA was 17.2/100 000 and was age-dependent (3.1 for ≤64 years, 34.3 for 65-74 years, 81.5 for 75-84 years, 216 for ≥85 years). A decrease in incidence was detected in the <65 year-age-group (incidence 4.98 in 2007 and 1.88 in 2017; p = 0.0018). Among older age groups, there was no significant change. Half (50.6%) of all amputees were diabetics. Altogether, 472 patients (53.0%) had a history of revascularization before LEA. 80.1% of index amputations were transfemoral and 19.9% transtibial. Re-surgery was performed on 94 (10.5%) patients. The 1-, 3- and 5-year overall survival were 56%, 30%, and 18%, respectively.

Conclusion

Our results suggest that in an aging population, despite good availability of vascular services, a significant number of patients are not fit for active revascularization, and LEA is the only feasible treatment for critical limb ischemia.

Prevalence and risk factors of lower limb amputations in patients with diabetic foot ulcers: A systematic review and meta-analysis

BACKGROUND AND AIMS

The study aimed at determining prevalence and risk factors (RFs) of diabetic lower limb amputations (LLAs).

METHODS

Electronic databases including PubMed, Medline, Web of Science, and Cochrane Library were searched from January 2003 to April 2021.

RESULTS

Sixteen full-text published studies were reviewed. The prevalence of LLAs stood as high as 66%, with a combined prevalence of 19% (95% CI 10-29) using the random-effects model. The most prominent RFs for LLA were duration of diabetes mellitus (DM), age, renal impairment, and ethnic minority. Amongst Australians, Indigenous background is strongly associated with increased risk of the diabetic foot (DF) LLA.

CONCLUSIONS

LLAs are considerably prevalent amongst patients with the DF and occur at even higher rates in patients with multimorbidity.

Major limb amputation and mortality in patients with neuro-ischaemic lower extremity wounds managed in a tertiary hospital: Focus on the differences among patients with diabetes, peripheral arterial disease and both

A majority of lower extremities neuro‐ischaemic wounds (NIU) are related to: (a) only diabetes (DM); (b) only peripheral artery disease (PAD); (c) co‐existing diabetes and peripheral artery disease (DM‐PAD). This study aims to characterise the major clinical outcomes of forementioned three groups of lower extremity wound patients in Singapore. Patients hospitalised for lower extremity NIU between January 2014 and October 2017 in a tertiary hospital in Singapore were analysed. Patients' major limb amputation and mortality were assessed using Cox regression models. Cumulative survival and amputation‐free survival among the three classified groups were calculated using Kaplan‐Meier analysis. Compared with patients with only DM, those in the PAD group and the DM‐PAD group had higher risk of major limb amputation (adjusted hazard ratio: 2.47, 95% CI: 1.65‐3.70; adjusted hazard ratio: 2.01, 95% CI: 1.53‐2.65 respectively) and mortality (adjusted hazard ratio: 2.36, 95% CI: 1.57‐3.55; adjusted hazard ratio: 2.46, 95% CI: 1.86‐3.26 respectively). The 3‐year survival and amputation‐free survival were lowest in the DM‐PAD group (52.1% and 41.5% respectively), followed by the PAD group (53.3% and 44.6% respectively) and the DM group (74.2% and 68.5% respectively). Lower extremity NIU patients with PAD or DM‐PAD were found to have poorer clinical prognosis than those with DM only.

A Review: Matrix Metallopeptidase-9 Nanoparticles Targeted for the Treatment of Diabetic Foot Ulcers

Diabetes foot ulcers are a leading cause of death in diabetic individuals. There are very few medicines and treatments that have received regulatory clearance for this indication, and numerous compounds from various pharmacological classes are now in various stages of clinical studies for diabetic foot ulcers treatment. Multiple risk factors contribute to diabetic foot ulcers, including neuropathy, peripheral artery disease, infection, gender, cigarette smoking, and age. The present difficulties in diabetic foot ulcers treatment are related to bacterial resistance to currently utilized antibiotics. Inhibition of the quorum sensing (QS) system and targeting matrix metallopeptidase-9 (MMP-9) are promising. This study focuses on the difficulties of existing treatment, current treatment technique, and novel pharmacological targets for diabetic foot ulcer. The electronic data base search diabetic for literature on foot ulcers treatment was carried out using Science Direct, PubMed, Google-Scholar, Springer Link, Scopus, and Wiley up to 2021. Becaplermin, a medication that targets MMP-9, glyceryl trinitrate, which inhibits the bacterial quorum sensing system, probiotic therapy, and nano technological solutions are just a few of the novel pharmaceuticals being developed for diabetic foot ulcers treatment. A combination of therapies, rather than one particular agent, will be the best option for treatment of Diabetes foot ulcer since it is multifactorial factors that render occurs of diabetic foot ulcer.

Mortality, Cardiovascular and Limb Events in Patients With Symptomatic Lower Extremity Artery Disease and Diabetes

The aim of this study was to compare the prognosis of patients according to diabetes status, during a 1-year follow-up after hospital admission for lower extremity artery disease, in the prospective COPART (COhorte de Patients ARTériopathes) registry. Inclusion criteria were intermittent claudication, ischemic rest pain, tissue loss, or acute limb ischemia, with radiological and hemodynamic confirmation. Among 2494 patients, 1235 (49.5%) had diabetes. Incidence rates for major adverse cardiovascular events (MACE) were 18.0/100 person-years (95% confidence interval [CI], 15.4-21.0) for the diabetes group and 11.1/100 person-years (95% CI, 9.2-13.4) for the non-diabetes group. Incidence rates of all-cause mortality were 29.8/100 person-years (95% CI, 26.5-33.4) for the diabetes group and 19.7/100 person-years (95% CI, 17.2-22.7) for the non-diabetes group. Incidence rates of major limb amputation were 24.2/100 person-years (95% CI, 21.1-27.8) for the diabetes group and 11.6/100 person-years (95% CI, 9.6-14.0) for the non-diabetes group. Diabetes was associated with MACE, adjusted hazard ratio 1.60 (95% CI, 1.16-2.22), and all-cause mortality, unadjusted HR 1.49 (95% CI, 1.24-1.78). In the multivariate analysis, diabetes was no longer associated with major amputation, adjusted HR 1.15 (95% CI, .87-1.51). Patients hospitalized for LEAD with diabetes had a higher risk of MACE than those without diabetes.

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.

Melatonin as a Trigger of Therapeutic Bone Regenerating Capacity in Biomaterials

Bone defects are usually treated with bone grafting. Several synthetic biomaterials have emerged to replace autologous and allogeneic bone grafts, but there are still shortcomings in bone regeneration. Melatonin has demonstrated a beneficial effect on bone metabolism with the potential to treat fractures, bone defects, and osteoporosis. The hormone promoted osteogenesis, inhibited osteoclastogenesis, stimulated angiogenesis, and reduced peri-implantitis around the graft. Recently, a growing number of studies showed beneficial effects of melatonin to treat bone defects. However, cellular and molecular mechanisms involved in bone healing are still poorly understood. In this review, we recapitulate the potential mechanisms of melatonin, providing a new horizon to the clinical treatment of bone defects.

Surgical wound dehiscence complicated by methicillin-resistant Staphylococcus aureus infection in a diabetic patient with femorotibial vascular bypass occlusion

Diabetic patients with critical limb ischaemia may be affected by severe wound and skin ulcer infections. We report a case of a patient with bilateral femorotibial occlusion and methicillin-resistant Staphylococcus aureus infection. The patient was treated with femoroperoneal vascular bypass, debridement of wound dehiscence and targeted antimicrobial therapy for symptom resolution and healing of the wound.

The impact of diabetes mellitus on major amputation among patients with chronic limb threatening ischemia undergoing elective endovascular therapy- a nationwide propensity score adjusted analysis

AIM

To investigate the risk of major amputation after elective endovascular therapy in patients with chronic limb threatening ischemia (CLTI) comparing patients with and without diabetes mellitus (DM).

METHODS

In this nationwide cohort study, all patients registered in the Swedish Vascular Register after elective endovascular therapy for CLTI caused by infra-inguinal arterial disease from 2010 to 2014 were included. Among 4578 individuals, 2251 had DM and were registered in the National Diabetes Register between 2009 and 2014. A propensity score adjusted Cox regression analysis was conducted to compare outcomes between groups. Median follow-up was 4.0 and 3.6 years for patients with DM and without DM, respectively.

RESULTS

The incidence rates of major amputation and acute myocardial infarction (AMI) were 43% (95% CI 1.23-1.67) and 37% (95% CI 1.13-1.67) higher, respectively, among patients with DM compared to patients without DM. There was no difference in mortality (HR 1.04, 95% CI 0.95-1.14).

CONCLUSIONS

Patients with DM had a higher risk of major amputation and AMI compared to those without DM after elective endovascular therapy for CLTI. Prevention of DM with CLTI is of utmost importance to reduce the risk of adverse limb and cardiovascular outcomes.

The impact of gender on diabetes-related lower extremity amputations: An Italian regional analysis on trends and predictors

BACKGROUND

Diabetes-related lower extremity amputations (LEAs) are a major public health issue. The aim of the study was to evaluate trends by gender and predictors of LEAs in an Italian region.

METHODS

Data were collected from hospital discharge records between 2006 and 2015. Gender- and age-adjusted standardised hospitalisation rates for major and minor amputations were calculated. Poisson regression model was performed to estimate trends in LEAs.

RESULTS

Hospitalisation rates decreased for minor amputations both among males (-30.0%) and females (-5.3%), while the major amputation rates decreased only for males (-44.7%). Males were at higher risk of undergoing major (IRR 1.41, 95%CI 1.19-1.67) and minor (IRR 1.62, 95%CI 1.45-1.82) amputations. Peripheral vascular disease was the leading predictor of major and minor amputations.

CONCLUSION

A significant reduction of LEAs was observed only for males. Identifying their predictable factors may help caregivers to provide higher standards of diabetes care.

[Macroangiopathy in diabetes mellitus]

Peripheral artery occlusive disease is a prevalent but underdiagnosed manifestation in patients with diabetes and also in patients with diabetic foot ulceration. There is insufficient awareness of its clinical manifestations, including intermittent claudication and critical limb ischemia and of its risk of adverse limb outcomes. This review aims to highlight essential elements of the prevalence of peripheral artery disease in patients with diabetes and the the pathway of clinical diagnosis. We report the actual standards and evidence based, interdisciplinary management including conservative, interventional and surgical treatment options and also the needs of follow-up care.

Therapeutic application of adipose-derived stromal vascular fraction in diabetic foot

Diabetic foot is one of the severest complications of diabetes. In severe cases, this disease may be lead to amputation or even death due to secondary infection and ischemic necrosis. Since the ineffectiveness of traditional therapy, autologous stem cell transplantation has been used to treat diabetic foot. This simple, safe, and effective therapy is expected to be applied and promoted in the future.In this review, we described the detailed pathogenesis of diabetic foot and the common clinical treatments currently used. We also revealed vascular remodeling as the potential mechanism of therapeutic functions of adipose-derived stromal vascular fraction (SVF) in treating diabetic foot.

Predicting the amputation risk for patients with diabetic foot ulceration - a Bayesian decision support tool

Background

Diabetes mellitus is a major global health issue with a growing prevalence. In this context, the number of diabetic complications is also on the rise, such as diabetic foot ulcers (DFU), which are closely linked to the risk of lower extremity amputation (LEA). Statistical prediction tools may support clinicians to initiate early tertiary LEA prevention for DFU patients. Thus, we designed Bayesian prediction models, as they produce transparent decision rules, quantify uncertainty intuitively and acknowledge prior available scientific knowledge.

Method

A logistic regression using observational collected according to the standardised PEDIS classification was utilised to compute the six-month amputation risk of DFU patients for two types of LEA: 1.) any-amputation and 2.) major-amputation. Being able to incorporate information which is available before the analysis, the Bayesian models were fitted following a twofold strategy. First, the designed prediction models waive the available information and, second, we incorporated the a priori available scientific knowledge into our models. Then, we evaluated each model with respect to the effect of the predictors and validity of the models. Next, we compared the performance of both models with respect to the incorporation of prior knowledge.

Results

This study included 237 patients. The mean age was 65.9 (SD 12.3), and 83.5% were male. Concerning the outcome, 31.6% underwent any- and 12.2% underwent a major-amputation procedure. The risk factors of perfusion, ulcer extent and depth revealed an impact on the outcomes, whereas the infection status and sensation did not. The major-amputation model using prior information outperformed the uninformed counterpart (AUC 0.765 vs AUC 0.790, Cohen’s d 2.21). In contrast, the models predicting any-amputation performed similarly (0.793 vs 0.790, Cohen’s d 0.22).

Conclusions

Both of the Bayesian amputation risk models showed acceptable prognostic values, and the major-amputation model benefitted from incorporating a priori information from a previous study. Thus, PEDIS serves as a valid foundation for a clinical decision support tool for the prediction of the amputation risk in DFU patients. Furthermore, we demonstrated the use of the available prior scientific information within a Bayesian framework to establish chains of knowledge.

Outcome of patients with chronic limb-threatening ischemia with and without revascularization

Summary: Background: Patients with chronic critical limb-threatening ischemia (CLTI) are at high risk of amputation and death. Despite the general recommendation for revascularization in CTLI in the guidelines, the underlying evidence for such a recommendation is limited. The aim of our study was to assess the outcome of patients with CLTI depending on the use of revascularization in a retrospective real-world cohort. Patients and methods: Administrative data of the largest German Health insurance (BARMER GEK) were provided for all patients that were hospitalized for the treatment of CLTI Rutherford category (RF) 5 and 6 between 2009 and 2011. Patients were followed-up until December 31st, 2012 for limb amputation and death in relation to whether patients did (Rx +) or did not have (Rx −) revascularization during index-hospitalization. Results: We identified 15,314 patients with CLTI at RF5 (n = 6,908 (45.1%)) and RF6 (n = 8,406 (54.9%)), thereof 7,651 (50.0%) underwent revascularization (Rx +) and 7,663 (50.0%) were treated conservatively (Rx −). During follow-up (mean 647 days; 95% CI 640–654 days) limb amputation (46.5% Rx− vs. 40.6% Rx+, P < 0.001) and overall mortality (48.2% Rx− vs. 42.6% Rx+, P < 0.001) were significantly lower in the subgroup Rx+. Conclusions: In a real-world setting, only half of CLTI were revascularized during the in-hospital treatment. Though, revascularization was associated with significantly better observed short- and long-term outcome. These data do not allow causal conclusion due to lack of data on the underlying reason for applied or withheld revascularization and therefore may involve a relevant selection bias.

Unmet medical needs in intermittent Claudication with diabetes and coronary artery disease-A "real-world" analysis on 21 197 PAD patients

BACKGROUND

Peripheral artery disease (PAD) is frequently co-prevalent with coronary artery disease (CAD) and diabetes (DM). The study aims to define the burden of CAD and/ or DM in PAD patients at moderate stages and further to evaluate its impact on therapy and outcome.

METHODS

Study is based on health insurance claims data of the BARMER reflecting an unselected "real-world" scenario. Retrospective analyses were based on 21 197 patients hospitalized for PAD Rutherford 1-3 between 1 January 2009 to 31 December 2011, including a 4-year follow-up (median 775 days).

RESULTS

In PAD patients, CAD is prevalent in 25.3% (n = 5355), DM in 23.5% (n = 4976), and both CAD and DM in 8.2% (n = 1741). Overall, in-hospital mortality was 0.4%, being increased if CAD was present (CAD alone: OR 1.849; 95%-CI 1.066-3.208; DM alone: OR 1.028; 95%-CI 0.520-2.033; CAD and DM: OR 3.115; 95%-CI 1.720-5.641). Both, CAD and DM increased long-term mortality (CAD alone: HR 1.234; 95%-CI 1.106-1.376; DM alone: HR 1.260; 95%-CI 1.125-1.412; CAD and DM: HR 1.76; 95%-CI 1.552-1.995). DM further increased long-term amputation risk (DM alone: HR 2.238; 95%-CI 1.849-2.710; DM and CAD: HR 2.199; 95%-CI 1.732-2.792), whereas CAD (alone) did not.

CONCLUSIONS

In a greater perspective, the data identify also mild to modest stage PAD patients at particular risk for adverse outcomes in presence of CAD and/or DM. CAD and DM both are related with a highly increased risk of long-term mortality even in intermittent claudication, and DM independently increased amputation risk.

Impact of diabetes type on treatment and outcome of patients with peripheral artery disease

BACKGROUND

The prevalence of diabetes mellitus and its associated complications such as peripheral artery disease is increasing worldwide. We aimed to explore the distinct impact of type 1 diabetes mellitus and type 2 diabetes mellitus on treatment and on short- and long-term outcome in patients with peripheral artery disease.

METHODS

Retrospective analysis of anonymized data of hospitalized patients covered by a large German health insurance. Assessment of patient's characteristics (comorbidities, complications, etc.) and outcome using multivariable Cox regression and Kaplan-Meier curves.

RESULTS

Among 41,702 patients with peripheral artery disease, 339 (0.8%) had type 1 diabetes mellitus and 13,151 (31.5%) had type 2 diabetes mellitus. Patients with diabetes mellitus had more comorbidities and complications than patients without diabetes mellitus ( p < 0.001). Type 1 diabetes mellitus patients exhibited the highest risk for limb amputation at 4-year follow-up (44.6% vs 35.1%, p < 0.001), while type 2 diabetes mellitus patients had higher mortality than type 1 diabetes mellitus (43.6% vs 31.0%, p < 0.001).

CONCLUSION

Although the fraction of type 1 diabetes mellitus among patients with peripheral artery disease and diabetes mellitus is low, it represents a subset of patients being at particular high risk for limb amputation. Research focused on elaborating the determinants of limb amputation and mortality in peripheral artery disease patients with diabetes mellitus is warranted to improve the poor prognosis of these patients.

Redefined clinical spectra of diabetic foot syndrome

Purpose

The aim of this study was to present the redefined clinical spectra of diabetic foot syndrome (RCS-DFS) and determine whether the RCS-DFS can be used to predict amputations.

Patients and methods

This is a retrospective study of type 2 diabetic patients referred with DFS for management at King Abdullah University Hospital (KAUH) between January 2014 and December 2015. Data collection form and diabetic foot (DF) characteristic chart were used to document the following: demographic data, diabetes-related parameters, DF characteristics, surgical interventions and amputations. The predominant clinical presentations of DF problems (ulcer, sepsis or gangrene) were integrated with the clinical criteria for diabetic foot infection (DFI) diagnosis and classification of Infectious Diseases Association of America (IDSA)/International Working Group on Diabetic Foot (IWGDF) to redefine the clinical spectra of DFS. Related risk characteristics and amputation rate at all levels were compared between the three RCS.

Results

In this study, there were 95 (47.0%) septic DFS (SDFS) patients, 65 (32.2%) ulcerative DFS (UDFS) patients and 42 (20.8%) gangrenous DFS (GDFS) patients. Poor glycemic control (HbA1c >7.5%), hypertension, history of the same foot problems, duration of symptoms, revascularizations and ischemic severity were significantly different between the three RCS. UDFS had the highest rate of limb salvage without amputations (70.8%). GDFS had the highest rate for final toe amputations (52.4%) and major amputations (23.8%). Final minor amputation rate was around 20% for both SDFS and GDFS.

Conclusion

Redefining DFS into ulcerative, septic and gangrenous by integration of the predominant clinical presentation and the clinical criteria for DFI diagnosis and classification of IDSA/IWGDF showed significant differences in amputation rate. Therefore, it can be used clinically to categorize patients with DFS to predict amputations and to help in planning their management. Further prospective studies are suggested to validate these results.

Current concepts for the evaluation and management of diabetic foot ulcers

The lifetime risk for diabetic patients to develop a diabetic foot ulcer (DFU) is 25%. In these patients, the risk of amputation is increased and the outcome deteriorates.More than 50% of non-traumatic lower-extremity amputations are related to DFU infections and 85% of all lower-extremity amputations in patients with diabetes are preceded by an ulcer; up to 70% of diabetic patients with a DFU-related amputation die within five years of their amputation.Optimal management of patients with DFUs must include clinical awareness, adequate blood glucose control, periodic foot inspection, custom therapeutic footwear, off-loading in high-risk patients, local wound care, diagnosis and control of osteomyelitis and ischaemia. Cite this article: EFORT Open Rev 2018;3:513-525. DOI: 10.1302/2058-5241.3.180010.

Transcutaneous oxygen pressure as a predictor for short-term survival in patients with type 2 diabetes and foot ulcers: a comparison with ankle-brachial index and toe blood pressure

AIMS

Ankle-brachial index (ABI) is the most commonly used test when diagnosing peripheral vascular disease and is considered a marker for cardiovascular risk. Transcutaneous oxygen pressure (TcPO₂), a test associated with microvascular function, has in several studies shown better correlation with diabetic foot ulcer (DFU) healing. Whether a low TcPO₂ could be a marker for mortality in the high-risk population of DFU patients has not been evaluated before. The aim of this study was to evaluate the predictive value of TcPO₂ in comparison with ABI and toe blood pressure (TBP) on 1-year mortality in type 2 diabetes patients with DFU.

METHODS

Type 2 diabetes patients aged ≤ 90 years, with one DFU who attended our multidisciplinary DFU-unit during year 2013-2015 and were screened with TcPO₂, ABI and TBP were retrospectively evaluated. One-year mortality was assessed from the national death register in Sweden.

RESULTS

A total of 236 patients (30% women) with a median age of 76 (69-82) years were evaluated in this study. Within 1 year, 14.8% of the patients died. TcPO₂ < 25 mmHg was associated with a higher 1-year mortality compared with TcPO₂ ≥ 25 mmHg (27.7 vs. 11.6%, p = 0.003). TBP and ABI did not significantly influence 1-year mortality. In a Cox regression analysis adjusted for confounders, TcPO₂ was independently predicting 1-year mortality with a hazard ratio for TcPO₂ < 25 mmHg of 2.8 (95% CI 1.34-5.91, p = 0.006).

CONCLUSIONS

This study indicates that a low TcPO₂ is an independent prognostic marker for 1-year mortality among patients with type 2 diabetes and DFU.

Cost-effectiveness analysis of the human recombinant epidermal growth factor in the management of patients with diabetic foot ulcers

Introduction: Diabetic foot ulcers are one of the most frequent complications of diabetes; such ulcers cause an increase in the costs of the health care of the diabetic patient and can even cause disability due to amputation in the patient. Although a proportion of patients achieve a spontaneous closure of ulcers, others require medical or surgical treatment. Objective: To determine the cost-effectiveness of the intra- and perilesional application of recombinant human epidermal growth factor (rhEGF), as opposed to conventional therapy for the management of patients diagnosed with Wagner's 3 or 4 diabetic foot ulcer in Colombia. Methodology: Using a Markov model, the process of care of a diabetic patient with diagnosis of Wagner's 3 or 4 ulcer receiving conventional treatment, or intra- and perilesional rhEGF, is configured. The evaluation cycles of the treatments are weekly over a 5-year horizon and the outcomes evaluated are quality-adjusted life years (QALYs) and the number of amputations avoided by each treatment scheme, in addition to the total costs for treatments. Results: For the analysed base case, in the outcome of amputations, it was found that the factor presents 39 fewer amputations, in a cohort of 100 patients, compared with conventional treatment. Likewise, QALYs are 0.65 more with the use of rhEGF in an average patient. The estimated cost-utility ratio for the base case would be below the threshold established for Colombia. Conclusions: The intra- and perilesional application of rhEGF is a more effective therapeutic option than conventional therapy in the treatment of patients with Wagner's 3 or 4 diabetic foot ulcers and is cost-effective, taking as an outcome the QALYs for Colombia from the perspective of the health system.

[Operative treatment of diabetics with vascular complications : Secondary data analysis of diagnosis-related groups statistics from 2005 to 2014 in Germany]

BACKGROUND

In Germany approximately 40,000 amputations per year are performed on patients with diabetes mellitus, often with accompanying vascular complications.

OBJECTIVE

The aim of this study was to present the various degrees of severity of the vascular complications and the temporal changes of the treatment options in diabetics with vascular complications in Germany.

MATERIAL AND METHODS

The microdata of the diagnosis-related groups (DRG) statistics of the Federal Statistical Office were analyzed over the period from 2005 to 2014. All cases were included in which the main or secondary diagnosis of diabetes mellitus with concurrent vascular complications (diabetic angiopathy and peripheral arterial disease) was encrypted.

RESULTS

The median age of the 1,811,422 cases was 73 years and 62% were male. While the total number of amputations remained stable over time, there was a 41% reduction in knee-preserving and a 31% reduction in non-knee preserving major amputations with an 18% increase in minor amputations. Revascularization increased by 33% from 36 procedures in 2005 to 48 procedures per 100,000 inhabitants. The increase in revascularization was evident in the area of endovascular therapy alone where there was an increase of 78%.

CONCLUSION

Due to the significant increase in endovascular revascularization measures, there was a significant increase in the proportion of diabetes patients with vascular pathologies in whom revascularization was carried out. As a result, improved limb preservation was achieved despite equally high amputation rates due to increasing minor amputation rates.

Testing the sympathetic nervous system of the foot has a high predictive value for early amputation in patients with diabetes with a neuroischemic ulcer

OBJECTIVE

There is evidence from the literature that dysfunctionality of the sympathetic nervous system of the foot with subsequent loss of local autoregulation could be a predictor of early amputation in patients with diabetes with a neuroischemic ulcer. To confirm this we tested the functionality of the sympathetic nervous system in the foot in a consecutive group of 31 patients with diabetes with critical limb ischemia and non-healing neuroischemic ulcer.

RESEARCH DESIGN AND METHODS

Prospective cohort with retrospective analysis after 12 months of routinely acquired clinical data. All patients in the study group underwent angiography of the foot as part of a routine angioplasty procedure. Primary study endpoint was lower extremity amputation-free survival at 12 months. Because of the study design no other endpoints could be analyzed. The functionality of the sympathetic nervous system was tested with perfusion angiography.

RESULTS

Thirty-one patients were followed for 12 months. The Capillary Resistance Index (CRI) was used to measure the response of the sympathetic nervous system. CRI≥0.9 is the cut-off point for a non-responsive sympathetic nervous system. All patients (n=11) with a CRI≥0.9 underwent a major amputation before 12 months. Of all patients with a CRI only 15% underwent major amputation. The positive predictive value for major amputation before 12 months for patients with a CRI ≥ 0.9 was 100%.

CONCLUSIONS

A non-responsive sympathetic nervous system of the foot is a strong predictor of early major amputation (log rank p<0.001; HR 14.22; 95% CI 3.64 to 55.51).

Norwegian trends in numbers of lower extremity revascularisations and amputations including regional trends in endovascular treatments for peripheral arterial disease: a retrospective cross-sectional registry study from 2001 to 2014

OBJECTIVE

The numbers of lower extremity revascularisations and amputations are insufficiently reported in Norway. To support future policy decisions regarding the provision of vascular treatment, knowledge of such trends is important.

METHODS

This retrospective cross-sectional study from 2001 to 2014 used data from the Norwegian Patient Registry. The revascularisation treatments were categorised in multilevel, aortoiliac, femoral to popliteal and popliteal to foot levels and sorted as open, endovascular and hybrid. The sessions in amputations were divided in major (thigh and below knee) and minor (ankle, foot or digit). Incidence rates were assessed per 100 000 for patients in the age group >60 years. The diabetic prevalence was calculated and the endovascular numbers at the South-Eastern, Western, Central and Northern Norway Regional Health Authority were compared.

RESULTS

The overall revascularisation rates increased from 308.7 to 366.8 (p=0.02). Open revascularisations decreased from 158.9 to 98.7 (p<0.01) while endovascular revascularisations increased from 142.2 to 243.4 (p<0.01). Hybrid revascularisations increased from 7.4 to 24.8 (p<0.01). Major amputation rates decreased from 87.8 to 48.7 (p<0.01) while minor amputations increased from 12.3 to 19.6 (p=0.01). The diabetic percentages increased from 12.2 to 22.3 (p<0.01) in revascularisations, from 26.5 to 30.8 (p=0.02) in major amputations and from 43.0 to 49.3 (p=0.13) in minor. (p values refer to average annual changes.) The regional trends in endovascular treatments varied within and between the vascular groups.

CONCLUSION

From 2001 to 2014, the revascularisation rates increased due to the rise in endovascular procedures. Open revascularisations and major amputation rates decreased, minor increased. The regional variances in endovascular treatments indicate that the availability of this technology differed between the health regions of Norway. The increase in patients with diabetes requires continued awareness of diabetes and its complications.

A safety evaluation of empagliflozin plus linagliptin for treating type 2 diabetes

INTRODUCTION

Dipeptidyl-peptidase-IV inhibitors (DPP-4i) and sodium-glucose-transporter-2 inhibitors (SGLT-2i) are oral antidiabetic drugs that improve glycemic parameters and possess a very low intrinsic hypoglycemia risk and favorable cardiovascular data. Areas covered: An overview on the clinical studies investigating the combination therapy with the DPP-4i linagliptin and the SGLT-2i empagliflozin is given. The clinical evidence for the efficacy and safety of free combinations as well as for their fixed dose combinations is presented. Empagliflozin has recently proved to reduce cardiovascular risk in type 2 diabetes and cardiovascular high risk situations. A fixed dose combination (FDC) of empagliflozin and linagliptin as add on therapy to metformin or as initial treatment lowered the HbA1c by approximately 1.1% and reduced the body weight by 2.0-3.0 kg. The hypoglycemia risk was not significantly increased. The relevant studies were identified by a search in Medline and in clinicaltrials.gov. Expert opinion/commentary: A DPP-4i/SGLT-2i FDC may be especially useful to simplify treatment, to reduce the tablet burden and to increase medication adherence. This FDC may be particularly beneficial for patients where the reduction of body weight, blood pressure and cardiovascular risk are important and in whom hypoglycemia should be avoided.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Reduced complexity of force and muscle activity during low level isometric contractions of the ankle in diabetic individuals

BACKGROUND

This study evaluated the structure and amount of variability of surface electromyography (sEMG) patterns and ankle force data during low-level isometric contractions in diabetic subjects with different degrees of neuropathy.

METHODS

We assessed 10 control subjects and 38 diabetic patients, classified as absent, mild, moderate, or severe neuropathy, by a fuzzy system based on clinical variables. Multichannel sEMG (64-electrode matrix) of tibialis anterior and gastrocnemius medialis muscles were acquired during isometric contractions at 10%, 20%, and 30% of the maximum voluntary contraction, and force levels during dorsi- and plantarflexion were recorded. Standard deviation and sample entropy of force signals were calculated and root mean square and sample entropy were calculated from sEMG signals. Differences among groups of force and sEMG variables were verified using a multivariate analysis of variance.

FINDINGS

Overall, during dorsiflexion contractions, moderate and severe subjects had higher force standard deviation and moderate subjects had lower force sample entropy. During plantarflexion, moderate subjects had higher force standard deviation and all diabetic subjects had lower entropy. Tibialis anterior presented higher root mean square in absent group and lower entropy in mild subjects. For gastrocnemius medialis, entropy was higher in severe and lower in moderate subjects.

INTERPRETATION

Diabetic neuropathy affects the complexity of the neuromuscular system during low-level isometric contractions, reducing the system's capacity to adapt to challenging mechanical demands. The observed patterns of neuromuscular complexity were not associated with disease severity, with the majority of alterations recorded in moderate subject.