HbA1c and Lower Extremity Amputation Risk in Patients With Diabetes

The potential impact and diagnostic value of inflammatory markers on diabetic foot progression in type II diabetes mellitus: A case-control study

BACKGROUND

The wound-healing process in diabetic foot is affected by pro and anti-inflammatory markers, and any disruption in the inflammatory reaction interferes with tissue homeostasis, leading to chronic non-wound healing.

AIM

This study aimed to determine the diagnostic value and effect of CRP, IL-6, TNF, and HbA1c on initiation the and progression of diabetic foot ulcers.

METHOD

ELISA was used to quantify IL-6, TNF, CRP, and HbA1c in 205 patients with diabetes, and 105 were diabetic foot free. The prevalence and progression of diabetic foot were also evaluated. The area under the curve (AUC) was calculated using the receiver operating characteristic (ROC) curve to analyze the predictive values. Forward stepwise logistic regression analysis was used to compute the odds ratio (OR) and the corresponding 95% confidence intervals (CIs).

RESULTS

CRP, IL-6, and FBS were found to be significant predictors of diabetic foot (OR=1.717, 95% CI=1.250-2.358, P=0.001; OR=1.434, 95% CI=1.142-1.802, P=0.002; and OR=1.040, 95% CI=1.002-1.080, P=0.037), respectively. The AUCs for CRP, IL-6, and HbA1c in predicting diabetic foot were 0.839, 0.728, and 0.834, respectively, demonstrating a good predictive value for each diagnostic marker.

CONCLUSION

The current study demonstrated that IL-6, CRP, and HbA1c may be useful biomarkers to indicate diabetic foot progression. Furthermore, our findings showed a substantial relationship between CRP and HbA1c in individuals with diabetic foot conditions.

Multicomponent prediction of 2-year mortality and amputation in patients with diabetic foot using a random survival forest model: Uric acid, alanine transaminase, urine protein and platelet as important predictors

The current methods for the prediction of mortality and amputation for inpatients with diabetic foot (DF) use only conventional, simple variables, which limits their performance. Here, we used a random survival forest (RSF) model and multicomponent variables to improve the prediction of mortality and amputation for these patients. We performed a retrospective cohort study of 175 inpatients with DF who were recruited between 2014 and 2021. Thirty-one predictors in six categories were considered as potential covariates. Seventy percent (n = 122) of the participants were randomly selected to constitute a training set, and 30% (n = 53) were assigned to a testing set. The RSF model was used to screen appropriate variables for their value as predictors of 2-year all-cause mortality and amputation, and a multicomponent prediction model was established. Model performance was evaluated using the area under the curve (AUC) and the Hosmer-Lemeshow test. The AUCs were compared using the Delong test. Seventeen variables were selected to predict mortality and 23 were selected to predict amputation. Uric acid and alanine transaminase were the top two most useful variables for the prediction of mortality, whereas urine protein and platelet were the top variables for the prediction of amputation. The AUCs were 0.913 and 0.851 for the prediction of mortality for the training and testing sets, respectively; and the equivalent AUCs were 0.963 and 0.893 for the prediction of amputation. There were no significant differences between the AUCs for the training and testing sets for both the mortality and amputation models. These models showed a good degree of fit. Thus, the RSF model can predict mortality and amputation in inpatients with DF. This multicomponent prediction model could help clinicians consider predictors of different dimensions to effectively prevent DF from clinical outcomes .

Diabetic foot in primary and tertiary ( DEFINITE ) Care: A health services innovation in coordination of diabetic foot ulcer ( DFU ) Care within a healthcare cluster ‐ 18‐month results from an observational population health cohort study

Diabetic Foot in Primary and Tertiary (DEFINITE) Care is an inter-institutional and multi-disciplinary team (MDT) health systems innovation programme at a healthcare cluster in Singapore. We aim to achieve coordinated MDT care across primary and tertiary care for patients with diabetic foot ulcers (DFU), within our public healthcare cluster - an integrated network of seven primary care polyclinics and two acute care tertiary hospitals (1700-bed and 800-bed) with a total catchment population of 2.2 million residents. Results from prospective DEFINITE Care is referenced against a retrospective 2013-2017 cohort, which was previously published. Cardiovascular profile of the study population is compared against the same population's profile in the preceding 12 months. Between June 2020 and December 2021, there were 3475 unique patients with DFU with mean age at 65.9 years, 61.2% male, mean baseline HbA1c at 8.3% with mean diabetes duration at 13.3 years, mean diabetes complication severity index (DCSI) at 5.6 and mean Charlson Comorbidity Index (CCI) at 6.8. In the 12-months preceding enrolment to DEFINITE Care, 35.5% had surgical foot debridement, 21.2% had minor lower extremity amputation (LEA), 7.5% had major LEA whilst 16.8% had revascularisation procedures. At 18-months after the implementation of DEFINITE Care programme, the absolute minor and major amputation rates were 8.7% (n = 302) and 5.1% (n = 176), respectively, equating to a minor and major LEA per 100000 population at 13.7 and 8.0, respectively. This represents an 80% reduction in minor amputation rates (P < .001) and a 35% reduction in major amputation rates (P = .005) when referenced against a retrospective 2013-2017 cohort, which had minor and major LEA per 100000 population at 68.9 and 12.4, respectively. As compared to the preceding 12 months, there was also a significant improvement in cardiovascular profile (glycemic and lipid control) within the DEFINITE population, with improved mean HbAc1 (7.9% from 8.4%, P < .001), low-density lipoprotein (LDL) levels (2.1 mmol/L from 2.2, P < .001), total cholesterol (3.9 mmol/L from 4.1, P < .001) and triglycerides levels (1.6 mmol/L from 1.8, P = .002). Multivariate analysis revealed a history of minor amputation in the preceding 12 months to be an independent predictor for major and minor amputation within the study period of 18 months (Hazard Ratio 3.4 and 1.8, respectively, P < .001). In conclusion, within DEFINITE care, 18-month data showed a significant reduction of minor and major LEA rates, with improved medical optimisation and cardiovascular profile within the study population.

Predictive factors and nomogram to evaluate the risk of below-ankle re-amputation in patients with diabetic foot

BACKGROUND

Diabetes mellitus, as the most common metabolic disease, is common worldwide and represents a crucial global health concern. The purpose of this research was to investigate the related risk factors and to develop a re-amputation risk nomogram in diabetic patients who have undergone an amputation.

METHODS

A observational analysis was performed on 459 patients who have underwent amputation for diabetic foot from January 2014 through December 2019 at the First Affiliated Hospital of Wenzhou Medical University. The least absolute shrinkage and selection operator regression and stepwise regression methods were implemented to determine risk selection for the re-amputation risk model, and the predictive nomogram was established with these features. Calibration curve, receiver operating characteristic curve, and decision curve analysis of this re-amputation nomogram were assessed.

RESULTS

Predictors contained in this predictive model included smoking, glycated hemoglobin A1c (HbA1c), ankle-brachial index (ABI) and C-reactive protein (CRP). Good discrimination with a C-index of 0.725 (95% CI, 0.6624-0.7876) and good calibration were displayed with this predictive model. The decision curve analysis showed that this re-amputation nomogram predicting risk adds more benefit than none strategy if the threshold probability of a patient was >6% and <59%.

CONCLUSIONS

This novel re-amputation nomogram incorporating smoking, glycated hemoglobin A1c (HbA1c), ankle-brachial index (ABI), C-reactive protein (CRP), and smoking could be easily used to predict individual re-amputation risk prediction in diabetic foot patients who have undergone an amputation. In the future, further analysis and external testing will be needed as much as possible to reconfirm that this new Nomogram can accurately predict the risk of toe re-amputation.

Glycated albumin and HbA1c as markers of lower extremity disease inUS adults with and without diabetes

AIM

We evaluated the associations of two biomarkers of hyperglycemia-hemoglobin A1c(HbA1c) and glycated albumin-with lower extremity disease in US adultsoverall and by diabetes status.

METHODS

We conducted a cross-sectional study of adult participants aged ≥ 40 years who attended the National Health and Nutrition Examination Survey (NHANES) 1999-2004 (unweighted N = 5,785). We used logistic regression to evaluate the associations of HbA1c and glycated albumin with lower extremity disease: peripheral neuropathy (assessed by monofilament test), peripheral artery disease (assessed by ankle-brachial index), history of foot ulcer, or amputation. All analyses were weighted and accounted for the complex NHANES sample survey design.

RESULTS

The prevalence of lower extremity disease was 17.4% (15.9% in adults without diabetes and 33.2% in adults with diabetes). HbA1c and glycated albumin were not significantly associated with lower extremity disease in adults without diabetes. However, we observed significant associations of both HbA1c (OR 1.19 per 1-% point increase, 95 %CI 1.06-1.34) and glycated albumin (OR 1.06 per 1-% point increase, 95 %CI 1.02-1.10) with lower extremity disease in adults with diabetes after adjustment. The patterns of association were similar for HbA1c and glycated albumin (P-for-seemingly-unrelated-regression = 0.60), with strong linear associations observed at high (diabetic) levels of both biomarkers.

CONCLUSIONS

Our study suggests the importance of diabetes prevention and glycemic control in adults with diabetes to reduce the burden of lower extremity disease.

Pattern and type of amputation and mortality rate associated with diabetic foot in Jeddah, Saudi Arabia: A retrospective Cohort Study

Background

Diabetic foot complications constitute a major public health problem worldwide, especially in Jeddah, Saudi Arabia, where the prevalence of diabetes is high. Our study was designed to determine the pattern and type of amputations performed on patients with diabetic foot admitted to a tertiary center in Jeddah, Saudi Arabia; we also aimed to determine the 7-year mortality rate of patients with diabetic foot at the same institution.

Materials and methods

This retrospective study was conducted between January 2013 and September 2020 at a tertiary center in Jeddah, Saudi Arabia. It included all patients previously diagnosed with diabetes mellitus who presented to the hospital with either diabetic foot ulcers or foot gangrene (dry/wet/gas). The medical records of 358 patients were reviewed to acquire information regarding demographics, admission history regarding diabetes and its outcome, medical and surgical history, the level of amputation, and the presence of infection.

Results

Among the participants, 84.9% underwent amputation, 38.2% underwent minor amputations, 40.1% underwent major amputations, and 21.7% underwent both types of amputation. The most common cause of amputation was infection (50.3%). There were 75 deaths and a 7-year mortality rate of 20%. Low mean hemoglobin and high mean creatinine levels were significantly associated with mortality (p < 0.05).

Conclusion

Efforts to decrease the risk of amputation and mortality among patients with diabetic foot complications are required. Early detection of the risk factors and intervention in specialist centers with a multidisciplinary approach is essential.

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Diabetic foot complications are a serious health problem, especially in our society.

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The risk for lower limb amputation increased significantly with a high hemoglobin A_1c.

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Once infection occurs, the risk of diabetic foot–related amputation significantly increases.

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Premature death was identified among patients underwent amputation.

Risk factors and incidence over time for lower extremity amputations in people with type 1 diabetes: an observational cohort study of 46,088 patients from the Swedish National Diabetes Registry

AIMS/HYPOTHESIS

The aim of this work was to study the incidence over time of lower extremity amputations and determine variables associated with increased risk of amputations in people with type 1 diabetes.

METHODS

Individuals with type 1 diabetes registered in the Swedish National Diabetes Registry with no previous amputation from 1 January 1998 and followed to 2 October 2019 were included. Time-updated Cox regression and gradient of risk per SD were used to evaluate the impact of risk factors on the incidence of amputation. Age- and sex-adjusted incidences were estimated over time.

RESULTS

Of 46,088 people with type 1 diabetes with no previous amputation (mean age 32.5 years [SD 14.5], 25,354 [55%] male sex), 1519 (3.3%) underwent amputation. Median follow-up was 12.4 years. The standardised incidence for any amputation in 1998-2001 was 2.84 (95% CI 2.32, 3.36) per 1000 person-years and decreased to 1.64 (95% CI 1.38, 1.90) per 1000 person-years in 2017-2019. The incidence for minor and major amputations showed a similar pattern. Hyperglycaemia and renal dysfunction were the strongest risk factors for amputation, followed by older age, male sex, cardiovascular comorbidities, smoking and hypertension. Glycaemic control and age- and sex-adjusted renal function improved during the corresponding time period as amputations decreased.

CONCLUSIONS/INTERPRETATION

The incidence of amputation and of the most prominent risk factors for amputation, including renal dysfunction and hyperglycaemia, has improved considerably during recent years for people with type 1 diabetes. This finding has important implications for quality of life, health economics and prognosis regarding CVD, indicating a trend shift in the treatment of type 1 diabetes.

Effect of reflexology on ankle brachial index, diabetic peripheral neuropathy, and glycemic control in older adults with diabetes: A randomized controlled trial

OBJECTIVE

The purpose of this study was to determine the effect of foot reflexology on ankle brachial index, diabetic peripheral neuropathy and glycemic control in older adults with diabetes.

METHODS

A randomized controlled, parallel-group trial study was conducted at the outpatient elderly health center in Bolu, Turkey. 48 adults aged 65 and over enrolled in the elderly health center were randomized into two groups in a ratio of 1:1 (experimental, n = 24; control, n = 24). Foot reflexology was performed for 12-week in the experimental group, whereas the control group continued their routine treatment and follow-up. The outcome measures included: (1) ankle brachial index, (2) diabetic peripheral neuropathy measured by a comprehensive foot exam, and (3) glycemic control by a glycated hemoglobin A blood test at baseline and after 12 weeks.

RESULTS

Post-test diabetic peripheral neuropathy scores (p < 0.001) and glycated hemoglobin A levels (p = 0.002) decreased in the experimental group and increased in the control group. There was no significant between-group difference regarding post-test ankle brachial index scores (p = 0.726). Foot reflexology had a medium effect size on diabetic peripheral neuropathy (95% confidence interval 0.003-2.24; d = 0.51; p < 0.001) and glycated hemoglobin A (95% confidence interval 0.72-1.22; d = 0.52; p = 0.002).

CONCLUSIONS

A foot reflexology practice can be a useful for improving the glycemic control and diabetic peripheral neuropathy in the older adults with diabetes.

TRIAL REGISTRATION NUMBER

NCT04416503.

Burning sensation in the feet and glycosylated haemoglobin levels in Swedish- and non-Swedish-born primary healthcare patients

BACKGROUND

A painful burning sensation in the feet is a common problem. The most common cause is small fibre neuropathy, a type of peripheral neuropathy that is often a consequence of diabetes and prediabetes.

AIM

To examine the association between a self-reported burning sensation in the feet and HbA1c levels in primary healthcare patients.

METHODS

This study used data from patients in the 4D diabetes project in Swedish primary healthcare. The study population included 824 patients. Logistic regression was performed to study the association between the outcome and explanatory variables.

RESULTS

A total of 24% of patients reported a burning sensation in the feet. This sensation was not associated with HbA1c levels. However, the probability of reporting a burning sensation was two times higher in non-Swedish-born than Swedish-born patients (OR, 2.31; 95% CI, 1.55-3.44) and higher in smokers than those who had never smoked, regardless of region of birth (OR, 1.69; 95% CI, 1.07-2.65).

CONCLUSIONS

Our results do not support the hypothesis that a self-reported burning sensation in the feet is associated with HbA1c levels. Rather, they indicate a strong relationship between a burning sensation and region of birth, as well as between a burning sensation and smoking.

Associations between attainment of incentivized primary care indicators and incident lower limb amputation among those with type 2 diabetes: a population-based historical cohort study

INTRODUCTION

England has invested considerably in diabetes care through such programs as the Quality and Outcomes Framework (QOF) and National Diabetes Audit (NDA). Associations between program indicators and clinical endpoints, such as amputation, remain unclear. We examined associations between primary care indicators and incident lower limb amputation.

RESEARCH DESIGN AND METHODS

This population-based retrospective cohort study, spanning 2010-2017, was comprised of adults in England with type 2 diabetes and no history of lower limb amputation. Exposures at baseline (2010-2011) were attainment of QOF glycated hemoglobin (HbA1c), blood pressure and total cholesterol indicators, and number of NDA processes completed. Propensity score matching was performed and multivariable Cox proportional hazards models, adjusting for disease-related, comorbidity, lifestyle, and sociodemographic factors, were fitted using matched samples for each exposure.

RESULTS

83 688 individuals from 330 English primary care practices were included. Mean follow-up was 3.9 (SD 2.0) years, and 521 (0.6%) minor or major amputations were observed (1.62 per 1000 person-years). HbA1c and cholesterol indicator attainment were associated with considerably lower risks of minor or major amputation (adjusted HRs; 95% CIs) 0.61 (0.49 to 0.74; p<0.0001) and 0.67 (0.53 to 0.86; p=0.0017), respectively). No evidence of association between blood pressure indicator attainment and amputation was observed (adjusted HR 0.88 (0.73 to 1.06; p=0.1891)). Substantially lower amputation rates were observed among those completing a greater number of NDA care processes (adjusted HRs 0.45 (0.24 to 0.83; p=0.0106), 0.67 (0.47 to 0.97; p=0.0319), and 0.38 (0.20 to 0.70; p=0.0022) for comparisons of 4-6 vs 0-3, 7-9 vs 0-3, and 7-9 vs 4-6 processes, respectively). Results for major-only amputations were similar for HbA1c and blood pressure, though cholesterol indicator attainment was non-significant.

CONCLUSIONS

Comprehensive primary care-based secondary prevention may offer considerable protection against diabetes-related amputation. This has important implications for diabetes management and medical decision-making for patients, as well as type 2 diabetes quality improvement programs.

The relation of anatomical distribution of symptomatic peripheral arterial disease (PAD) with HbA1c level in patients with type 2 diabetes mellitus

AIMS

Increased level of glycated hemoglobin (HbA1c) is associated with an increased prevalence of peripheral arterial disease (PAD). This study aimed to assess the relationship between the anatomical distribution of symptomatic PAD lesions in patients with type 2 diabetes and HbA1c levels at the time of PAD diagnosis.

PATIENTS AND METHODS

A retrospective study was conducted at King Abdullah University Hospital during the period August 2011 to December 2015. Consecutive patients with type 2 diabetes presented with symptomatic PAD confirmed by computed tomography-angiography (CTA) were included in this study. CTA images were reviewed. Relevant information including demographic data, PAD symptoms, comorbidities, HbA1c level, lipid profile, C-reactive protein and the mean platelets volume were retrieved from medical records.

RESULTS

A total of 332 patients with type 2 diabetes (255 males and 77 females) were included in this study. The mean HbA1c at the time of PAD diagnosis was 8.68% (±2.06%). The prevalence of hemodynamic relevant atherosclerotic lesions of the superficial femoral artery, popliteal artery, leg vessels, femoro-popliteal, and crural segments was significantly higher in patients with HbA1c >7.5% compared with patients with HbA1c ⩽7.5%.

CONCLUSION

The anatomical distribution of symptomatic PAD in patients with type 2 diabetes mellitus differed significantly according to HbA1c level at the time of PAD diagnosis.

Clinical and economic burden of diabetic foot ulcers: A 5-year longitudinal multi-ethnic cohort study from the tropics

Diabetic foot ulcers (DFUs) present a substantial clinical and economic burden to healthcare systems around the world, with significant reductions in quality of life for those affected. We aimed to analyse the clinical and economic burden of DFU via a 5-year longitudinal multi-ethnic cohort study. A longitudinal analysis of inpatient and outpatient DFUs data over 5 years from a university tertiary hospital in Singapore was performed. Data included baseline characteristics, clinical outcomes, hospitalisation, and outpatient details. Descriptive statistics, Kaplan-Meier survival analyses, and Cox proportional hazard models were performed. Patients treated for DFUs (n = 1729, mean patient age of 63·4 years) were assessed. The cohort consists of Chinese (61.4%), Malay (13.5%), and Indian (18.4%) patients. Common comorbidities included peripheral arterial disease (74.8%), peripheral neuropathy (14.5%), and a median haemoglobin A1c of 9.9%. Patients underwent toe(s) amputation (36.4%), transmetatarsal amputations (16.9%), or major amputations (6·5%). The mean length of inpatient stay for ulcer-only, minor amputation, and major amputation was 13.3, 20.5, and 59.6 days, respectively. Mean cost per patient-year was US $3368 (ulcer-only), US $10468 (minor amputation), and US $30131 (major amputation). Minor amputation-free survival was 80.9% at 1 year and 56.9% at 5 years, while major amputation-free survival was 97.4% at 1 year and 91.0% at 5 years. In conclusion, within our multi-ethnic cohort of patients from the tropics, there was significant clinical and economic burden of DFUs, with a high wound per patient ratio and escalating healthcare costs corresponding to more proximal amputation levels.

Glycemic control and diabetic foot ulcer outcomes: A systematic review and meta-analysis of observational studies

OBJECTIVE

To evaluate the association between glycemic control (hemoglobin A1C, fasting glucose, and random glucose) and the outcomes of wound healing and lower extremity amputation (LEA) among patients with diabetic foot ulcers (DFUs).

RESEARCH DESIGN AND METHODS

Medline, EMBASE, Cochrane Library, and Scopus were searched for observational studies published up to March 2019. Five independent reviewers assessed in duplicate the eligibility of each study based on predefined eligibility criteria and two independent reviewers assessed risk of bias. Ameta-analysis was performed to calculate a pooled odds ratio (OR) or hazard ratio (HR) using random effects for glycemic measures in relation to the outcomes of wound healing and LEA. Subgroup analyses were conducted to explore potential source of heterogeneity between studies. The study protocol is registered with PROSPERO (CRD42018096842).

RESULTS

Of 4572 study records screened, 60 observational studies met the study eligibility criteria of which 47 studies had appropriate data for inclusion in one or more meta-analyses(n = 12,604 DFUs). For cohort studies comparing A1C >7.0 to 7.5% vs. lower A1C levels, the pooled OR for LEA was 2.04 (95% CI, 0.91, 4.57) and for studies comparing A1C ≥ 8% vs. <8%, the pooled OR for LEA was 4.80 (95% CI 2.83, 8.13). For cohort studies comparing fasting glucose ≥126 vs. <126 mg/dl, the pooled OR for LEA was 1.46 (95% CI, 1.02, 2.09). There was no association with A1C category and wound healing (OR or HR). There was high risk of bias with respect to comparability of cohorts as many studies did not adjust for potential confounders in the association between glycemic control and DFU outcomes.

CONCLUSIONS

Our findings suggest that A1C levels ≥8% and fasting glucose levels ≥126 mg/dl are associated with increased likelihood of LEA in patients with DFUs. A purposively designed prospective study is needed to better understand the mechanisms underlying the association between hyperglycemia and LEA.

The impact of hemoglobin A1c on outcomes after lower extremity bypass

OBJECTIVE

Diabetes has been shown to be associated with increased risk of postoperative complications after lower extremity bypass (LEB), although it is unclear whether medium-term glucose control affects outcomes. This study aimed to assess the association of perioperative hemoglobin A_1c (HbA_1c) level on perioperative outcomes after LEB.

METHODS

We examined consecutive infrainguinal LEBs for chronic limb-threatening ischemia (CLTI) using the Vascular Quality Initiative database (2007-2018). Perioperative HbA_1c levels were stratified into <5.7%, 5.7% to 6.5%, and >6.5%. Propensity score matching on demographics, medical history, and procedural characteristics was used to select comparable patients across HbA_1c groups. The primary outcome was postoperative wound infection. Multivariable analyses were performed for matched and unmatched groups using Cox proportional hazards models for survival outcomes and logistic regression for binary outcomes with association expressed by adjusted hazard ratio (aHR) or adjusted odds ratio (aOR) and corresponding 95% confidence intervals (CIs).

RESULTS

The CLTI cohort included 8171 infrainguinal LEBs: 631 (7.7%) had HbA_1c <5.7%; 1691 (20.6%), 5.7% to 6.5%; and 5849 (71.6%), >6.5%. There was no difference in rates of wound infection in the CLTI cohort (HbA_1c ≤5.7%, 3.8%; HbA_1c 5.7%-6.5%, 3.7%; HbA_1c >6.5%, 3.2%; P = .53) or matched cohort (4.3%, 4.5%, 3.4%; P = .62). There were no differences in perioperative mortality in the CLTI cohort (2.5%, 1.7%, 1.5%; P = .16) or the matched cohort (2.7%, 2.3%, 2.2%; P = .84). In multivariable analysis, there was no significant association between HbA_1c and wound infection in the CLTI cohort (HbA_1c 5.7%-6.5% vs <5.7%: aOR, 0.91 [95% CI, 0.56-1.50; P = .72]; HbA_1c >6.5% vs <5.7%: aOR, 0.81 [95% CI, 0.52-1.26; P = .35]). There was, however, a significant association between decreased HbA_1c and mortality (HbA_1c 5.7%-6.5% vs <5.7%: aHR, 0.77 [95% CI, 0.61-0.97; P = .03]; HbA_1c >6.5% vs <5.7%: aHR, 0.75 [95% CI, 0.61-0.93; P = .01]).

CONCLUSIONS

Our study suggests no significant association of increased HbA_1c level and perioperative complications. Additional investigation is required to further evaluate the impact of short-term glycemic control and long-term outcomes of patients undergoing LEB.

Does Perioperative Hemoglobin A1c Level Affect the Incidence, Pattern and Mortality of Lower Extremity Amputation?

BACKGROUND

We hypothesized that perioperative HbA1c influenced the pattern and outcomes of Lower Extremity Amputation (LEA).

METHODS

A retrospective analysis was conducted for all patients who underwent LEA between 2000 and 2013. Patients were categorized into 5 groups according to their perioperative HbA1c values [Group 1 (<6.5%), Group 2 (6.5-7.4%), Group 3 (7.5-8.4%), Group 4 (8.5-9.4%) and Group 5 (≥9.5%)]. We identified 848 patients with LEA; perioperative HbA1c levels were available in 547 cases (Group 1: 18.8%, Group 2: 17.7%, Group 3: 15.0%, Group 4: 13.5% and Group 5: 34.9%). Major amputation was performed in 35%, 32%, 22%, 10.8% and 13.6%, respectively.

RESULTS

The overall mortality was 36.5%; of that one quarter occurred during the index hospitalization. Mortality was higher in Group 1 (57.4%) compared with Groups 2-5 (46.9%, 38.3%, 36.1% and 31.2%, respectively, p=0.001). Cox regression analysis showed that poor glycemic control (Group 4 and 5) had lower risk of mortality post-LEA [hazard ratio 0.57 (95% CI 0.35-0.93) and hazard ratio 0.46 (95% CI 0.31-0.69)]; this mortality risk persisted even after adjustment for age and sex but was statistically insignificant. The rate of LEA was greater among poor glycemic control patients; however, the mortality was higher among patients with tight control.

CONCLUSION

The effects of HbA1c on the immediate and long-term LEA outcomes and its therapeutic implications need further investigation.

A ‘Speed-Dating’ Model of Wound Care? Rapid, High-Volume Assessment of Patients With Diabetes in a Multidisciplinary Foot Wound Clinic

Background Diabetes is a major risk factor for foot ulceration and leg amputation, but the effect of intensive glycaemic control on wound healing is unknown. While an interdisciplinary approach has been shown to be important in the management of diabetic foot ulcer (DFU), there is no standardised definition of such an interdisciplinary team.

Objective To investigate the role of an opportunistic, rapid-access, inter-disciplinary model of diabetes care at a foot wound clinic.

Methods A retrospective case-control study of patients with DFUs attending a diabetes foot wound clinic over a 6-month period. Outcomes in patients who were seen by a rapid-access interdisciplinary team (RAIT) consisting of an endocrinologist, diabetes educator and dietician during the standard wound care those who were not seen by this team were compared.

Results Fifty-five patients were seen by the RAIT and 64 control patients were not seen by this team during their attendance of a diabetes foot wound clinic. Patients in the intervention group had non-significantly higher baseline HbA1c and a significantly larger proportion were active cigarette smokers. Both groups achieved comparable reduction in the total number of DFUs per patient (p=0.971). Patients in the intervention group had a 60.1% reduction in wound size compared to 52.4% reduction in control group (p=0.526).

Conclusion Our study shows that the use of a rapid-access interdisciplinary team to assess and manage patients’ diabetes in a foot wound clinic is feasible. Patients with higher-risk diabetes foot wounds exposed to RAIT had comparable wound healing outcomes to lower risk patients.

Association between glucose variation and lower extremity amputation incidence in individuals with type 2 diabetes: a nationwide retrospective cohort study

AIMS/HYPOTHESIS

Elevated glucose level is one of the risk factors for lower extremity amputation (LEA), but whether glycaemic variability confers independent risks of LEA remains to be elucidated. This study aimed to investigate the association between visit-to-visit glycaemic variability and minor and major LEA risks during 8 years of follow-up in type 2 diabetic individuals aged 50 years and older.

METHODS

This retrospective cohort study included 27,574 ethnic Chinese type 2 diabetic individuals aged ≥50 years from the National Diabetes Care Management Program in Taiwan. Glycaemic variability measures were presented as the CVs of fasting plasma glucose (FPG-CV) and of HbA_1c (A_1c-CV). The effect of glycaemic variability on the incidence of LEA events was analysed using Cox proportional hazards models.

RESULTS

After a median follow-up of 8.9 years, 541 incident cases of LEA with a crude incidence density rate of 2.4 per 1000 person-years were observed. After multivariate adjustment, FPG-CV and A_1c-CV were found to be significantly associated with minor LEA, with corresponding HRs of 1.53 (95% CI 1.15, 2.04) and 1.34 (95% CI 1.02, 1.77) for the third tertiles of FPG-CV and A_1c-CV, respectively. In addition, these associations were stronger amongst older adults with longer diabetes duration (≥3 years) than amongst those with shorter duration (<3 years) (p_interaction < 0.01).

CONCLUSIONS/INTERPRETATION

Our study suggests that visit-to-visit variations in HbA_1c and FPG are important predictors of minor LEA amongst older adults with type 2 diabetes, particularly for those with more than 3 years of diabetes duration.

Diabetic Foot Infection Presenting Systemic Inflammatory Response Syndrome: A Unique Disorder of Systemic Reaction from Infection of the Most Distal Body

Diabetic foot infection (DFI) is a major complication of diabetic foot that lead to nontraumatic lower-extremity amputation (LEA). Such distal infection of the body having systemic inflammatory response syndrome (SIRS) is rarely reported. Consecutive patients treated for limb-threatening DFI in a major diabetic foot center in Taiwan were analyzed between the years 2014 to 2017. Clinical factors, laboratory data, perfusion, extent, depth, infection and sensation (PEDIS) wound score in 519 subjects with grade 3 DFI and 203 presenting SIRS (28.1%) were compared. Major LEA and in-hospital mortality were defined as poor prognosis. Patients presenting SIRS had poor prognosis compared with those with grade 3 DFI (14.3% versus 6.6% for major LEA and 6.4% versus 3.5% for in-hospital mortality). Age, wound size, and HbA1c were independent risk factors favoring SIRS presentation. Perfusion grade 3 (odds ratio 3.37, p = 0.044) and history of major adverse cardiac events (OR 2.41, p = 0.036) were the independent factors for poor prognosis in treating patients with DFI presenting SIRS. SIRS when presented in patients with DFI is not only limb- but life-threatening as well. Clinicians should be aware of the clinical factors that are prone to develop and those affecting the prognosis in treating patients with limb-threatening foot infections.

Factors associated with lower-extremity amputation in patients with diabetic foot ulcers in a Chinese tertiary care hospital

Providing a better understanding of the risk factors for amputation in this particular region, Hunan province, in China might help patients with diabetic foot ulcers receive timely and appropriate medical care and help prevent amputation. Diabetic foot ulcer patients referred to the Third Xiangya Hospital during the period between December 2014 and September 2018 were enrolled. Participants who underwent amputations and received conservative treatments were compared using univariate and multivariate analyses to identify the independent predictors of amputation. Those who required amputation presented significantly higher levels of white blood cell counts, platelet counts, erythrocyte sedimentation rate, C-reactive protein, and glycated haemoglobin (HbA1c) levels. However, levels of haemoglobin, postprandial plasma C-peptide, triglyceride, high-density lipoprotein cholesterol, albumin, and uric acid were decreased in patients with amputations. Patients with more advanced Wagner grades had much higher rates of amputation. Multivariable-adjusted odds ratios in stepwise logistic regression model was 1.317 for HbA1c (95% CI: 1.015-1.709), 0.255 for triglyceride (95% CI: 0.067-0.975), and 20.947 for Wagner grades (95% CI: 4.216-104.080). Independent risk factors for amputation in these Chinese diabetic foot ulcer patients included an elevated HbA1c level, lower triglyceride level, and higher Wagner grades.

Healing of Diabetic Foot Ulcers in Patients Treated at the Copenhagen Wound Healing Center in 1999/2000 and in 2011/2012

AIM

To describe differences in healing time of diabetic foot ulcers for patients treated at the Copenhagen Wound Healing Center, Bispebjerg Hospital, between the years 1999/2000 and 2011/2012. The Center is highly specialized and receives diabetes patients with hard-to-heal foot ulcers. A further aim is to attempt to find predictors of healing time of diabetic foot ulcers.

METHODS

A retrospective descriptive study of records from patients with diabetic foot ulcer treated at the Copenhagen Wound Healing Center in 1999, 2000, 2011, or 2012. Follow-up data was collected until the 3^rd of August 2018.

RESULTS

Median time (range) to healing was 6 (61.3) months in 1999/2000 and 6.6 (67.8) in 2011/2012 (p = 0.2). About 33% of ulcers were healed, 17% were minor or major amputated, and 1.5% were dead within one year in 1999/2000, whereas 30% of ulcers were healed (p = 0.6), 14% were amputated (p = 0.2), and 12.8% were dead within one year in 2011/2012 (p < 0.001). The single factor found significantly associated with longer ulcer duration was infection. Related to shorter ulcer duration were toe localization of the ulcer and good glycemic control.

CONCLUSION

The median time to healing of a diabetic foot ulcer was long, around 6 months and with a high recurrence rate in 1999/2000 as well as in 2011/2012. Some factors were found to be significantly related to healing time, and intervention addressing these may improve the time to heal, although such interpretations must be taken with precaution from the present study and should be proven in randomized prospective intervention trials.

On the Cutting Edge: Wound Care for the Endovascular Specialist

Clinical outcomes in patients with critical limb ischemia (CLI) depend not only on endovascular restoration of macrovascular blood flow but also on aggressive periprocedural wound care. Education about this area of CLI therapy is essential not only to maximize the benefits of endovascular therapy but also to facilitate participation in the multidisciplinary care crucial to attaining limb salvage. In this article, we review the advances in wound care products and therapies that have granted the wound care specialist the ability to heal previously nonhealing wounds. We provide a primer on the basic science behind wound healing and the pathogenesis of ischemic wounds, familiarize the reader with methods of tissue viability assessment, and provide an overview of wound debridement techniques, dressings, hyperbaric therapy, and tissue offloading devices. Lastly, we explore emerging technology on the horizons of wound care.

To Smoke or Not To Smoke: Cigarettes Have a Negative Effect on Wound Healing of Diabetic Foot Ulcers

Diabetic foot ulcers (DFUs) have a complex pathophysiology and require an expert multidisciplinary treatment. There are several, both systemic and local, risk factors for DFUs. A recent meta-analysis of 18 studies has now provided robust evidence on the detrimental effect of smoking on healing of DFUs. Indeed, healing rates were consistently lower among smokers than among nonsmokers. Based on this new evidence, it is reasonable to consider the utility of smoking cessation programs. Incorporation of the latter into the holistic therapeutic strategy for DFUs may be anticipated to improve healing rates, but this remains to be shown.

Association Between Cigarette Smoking and Diabetic Foot Healing: A Systematic Review and Meta-Analysis

The role of smoking for wound healing in patients with diabetic foot has been unclear. This meta-analysis examined the relationship between cigarette smoking and diabetic foot wound healing. Observational studies for the association between smoking and diabetic foot wound healing of patients were systematically searched through PubMed and Wanfang Data, published up to June 2018. Healing rates of wounds were recognized as outcomes. Meta-analysis models were chosen by heterogeneity. A total of 3388 eligible studies were identified, of which 18 met all our inclusion criteria. In the smoking group, healing rate had an average of 62.1%, ranging from 20.0% to 89.6%; in the nonsmoking group, healing rate had an average of 71.5%, ranging from 40.2% to 93.8%. A significant association was found between smoking and the healing of diabetic foot wounds ( z = 3.08; P = .002), with an odds ratio (OR) of 0.70 (95% CI = 0.56-0.88), based on a random-effects model. Meta-regression analyses indicated that the heterogeneity did not come from publication year ( t = -0.50, P = .622) or overall healing rate ( t = 0.16, P = .872). The leave-one-out sensitivity analysis was robust; sensitivity analysis for pooled estimate of adjusted ORs had an OR of 0.20 (95% CI = 0.07-0.56; z = 3.08; P = .002). Subgroup analysis had an OR of 0.62 (95% CI = 0.41-0.95; z = 2.21; P = .027) in retrospective cohort studies and had an OR of 0.75 (95% CI = 0.57-0.99; z = 2.02; P = .043) in prospective cohort studies. Our meta-analysis indicated that smoking had an overall negative effect on the wound healing of diabetic foot individuals. This study provides evidence for the harm of smoking to diabetic foot and may help reduce the medical and economic burden on poor healing of diabetic foot.

Predictors of major lower limb amputation in type 2 diabetic patients referred for hospital care with diabetic foot syndrome

PURPOSE

This study was conducted to determine the risk factors of major lower extremity amputations in type 2 diabetic patients referred for hospital care with diabetic foot syndrome.

PATIENTS AND METHODS

This retrospective study involved 225 type 2 diabetic patients referred for management of diabetic foot syndrome at King Abdullah University Hospital in the period between January 2014 and December 2015. A structured customized diabetic foot data collection form with diabetic foot characteristics chart was used for documentation of relevant information, which checks for age, sex, body mass index, smoking, duration of diabetes, diabetic control therapy, associated hypertension, cardiac diseases, stroke, chronic renal impairment, renal replacement therapy (hem-dialysis), and history of diabetes-related complication in both feet prior to the study period. The predictors for major lower limb amputations were compared between groups using chi-square test, and binary logistic regression was used to determine the factors associated with major amputation.

RESULTS

Twenty-seven limbs underwent major amputations with an overall rate of major amputation of 11.6%. The following predictors were found to be associated with the higher incidence of major lower limb amputations: duration of diabetes ≥15 years, HbA1c ≥8%, patients on insulin, with hypertension, cardiac diseases, chronic renal impairment, stroke, having gangrene, higher number of components, higher Wagner classification, and ischemia. However, the rate did not differ significantly between men and women.

CONCLUSION

Presentation with gangrenous tissue and poor glycemic control are the important risks and significant predictive factors for type 2 diabetes-related major lower limb amputations.

Risk of lower extremity amputations in people with type 2 diabetes mellitus treated with sodium-glucose co-transporter-2 inhibitors in the USA: A retrospective cohort study

AIMS

To examine the incidence of amputation in patients with type 2 diabetes mellitus (T2DM) treated with sodium glucose co-transporter 2 (SGLT2) inhibitors overall, and canagliflozin specifically, compared with non-SGLT2 inhibitor antihyperglycaemic agents (AHAs).

MATERIALS AND METHODS

Patients with T2DM newly exposed to SGLT2 inhibitors or non-SGLT2 inhibitor AHAs were identified using the Truven MarketScan database. The incidence of below-knee lower extremity (BKLE) amputation was calculated for patients treated with SGLT2 inhibitors, canagliflozin, or non-SGLT2 inhibitor AHAs. Patients newly exposed to canagliflozin and non-SGLT2 inhibitor AHAs were matched 1:1 on propensity scores, and a Cox proportional hazards model was used for comparative analysis. Negative controls (outcomes not believed to be associated with any AHA) were used to calibrate P values.

RESULTS

Between April 1, 2013 and October 31, 2016, 118 018 new users of SGLT2 inhibitors, including 73 024 of canagliflozin, and 226 623 new users of non-SGLT2 inhibitor AHAs were identified. The crude incidence rates of BKLE amputation were 1.22, 1.26 and 1.87 events per 1000 person-years with SGLT2 inhibitors, canagliflozin and non-SGLT2 inhibitor AHAs, respectively. For the comparative analysis, 63 845 new users of canagliflozin were matched with 63 845 new users of non-SGLT2 inhibitor AHAs, resulting in well-balanced baseline covariates. The incidence rates of BKLE amputation were 1.18 and 1.12 events per 1000 person-years with canagliflozin and non-SGLT2 inhibitor AHAs, respectively; the hazard ratio was 0.98 (95% confidence interval 0.68-1.41; P = .92, calibrated P = .95).

CONCLUSIONS

This real-world study observed no evidence of increased risk of BKLE amputation for new users of canagliflozin compared with non-SGLT2 inhibitor AHAs in a broad population of patients with T2DM.

Risk of lower limb amputation in a national prevalent cohort of patients with diabetes

AIMS/HYPOTHESIS

Lower limb amputation is a serious complication of diabetes mellitus. Understanding how amputation risk differs by population subgroups is crucial in terms of directing preventive strategies. In this study, we describe those factors that impact amputation risk in the entire prevalent diabetic population of New Zealand.

METHODS

A national prevalent cohort of 217,207 individuals with diabetes in 2010 were followed up until the end of 2013 for lower limb amputations, and 2014 for mortality. Inpatient hospitalisation data were used to define lower limb amputation using ICD-10 codes. Cox proportional hazards models were used to describe relative hazard of amputation over the follow-up period.

RESULTS

A total of 784 individuals (3.6 cases/1000 individuals) underwent a major (above-ankle) lower limb amputation during follow-up, while 1217 (5.6/1000) underwent a minor (below ankle) amputation. The risk of major and minor amputation was 39% and 77% greater for men than women, respectively (adjusted HR: major amputation 1.39, 95% CI 1.20, 1.61; minor amputation 1.77, 95% CI 1.56, 2.00). Indigenous Māori were at 65% greater risk of above-knee amputation compared with the European/Other diabetic population (HR 1.65, 95% CI 1.37, 1.97). Amputation risk increased with increasing comorbidity burden, and peripheral vascular disease conferred the greatest independent risk of all comorbid conditions. Prior minor amputation increased the risk of subsequent major amputation by tenfold (HR 10.04, 95% CI 7.83, 12.87), and increased the risk of another minor amputation by 20-fold (HR 21.39, 95% CI 17.89, 25.57). Death was common among the total cohort, but particularly among those who underwent amputation, with more than half of those who underwent a major amputation dying within 3 years of their procedure (57%).

CONCLUSIONS/INTERPRETATION

Using a large, well-defined, national prevalent cohort of people with diabetes, we found that being male, indigenous Māori, living in deprivation, having a high comorbidity burden and/or having a previous amputation were strongly associated with subsequent risk of lower limb amputation. The use of this prevalent cohort strengthens the value of our estimates in terms of applicability to the general population, and highlights the subgroups at greatest risk of lower limb amputation.

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

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

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.