Long-term results following operation for diabetic foot problems: arterial disease confers a poor prognosis

Long-term Mortality of a Cohort of Patients Undergoing Surgical Treatment for Diabetic Foot Infections. An 8-year Follow-up Study

We analyzed a retrospective cohort of 150 patients with diabetic foot infections (DFIs) who underwent surgical treatment to determine long-term outcomes. The median follow-up of the series was 7.6 years. Cox's proportional hazards model for survival time was performed and hazard ratios (HRs) were estimated. Survival times were plotted using the Kaplan-Meier method. Fifteen patients (10%) required readmission after discharge from the hospital for a recurrence of the infection. Ninety patients (60%) had re-ulcerations. Forty-nine (54.4% of those re-ulcerated) required new admission and 24 of them (26.6% of those re-ulcerated) finally required a new amputation. Overall cumulative survival rates at 1, 5, and 8 years were 95%, 78%, and 64%, respectively. Predictive variables of long-term mortality were insulin treatment (HR: 2.0, 95% CI: 1.1-3.6, P = .01), female sex (HR: 3.1, 95% CI: 1.7-5.3, P<.01) and estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m² (HR: 2.2, 95% CI: 1.1-4.2, P = .01). In conclusion, patients undergoing surgical treatment for DFIs had a high rate of recurrences and mortality. Women, patients who underwent treatment with insulin, and those with eGFR <60 ml/min/1.73 m² had a higher risk of long-term mortality.

Tenfold risk increase of major cardiovascular events after high limb amputation with non-compliance for secondary prevention measures

Background The aim of the study was to evaluate the impact of compliance with lifestyle recommendations and medication on 1-year prevention of major adverse cardiovascular events (MACE) in patients with type 2 diabetes (T2D) after trans-femoral amputation (TFA). Methods In this prospective single-center interventional cohort study, 179 consecutive T2D patients with symptomatic coronary artery disease (CAD) underwent 1-year follow-up examination after TFA in 2013. Lower limb and coronary artery CT angiography were provided before surgery; physical examination and laboratory tests were performed at baseline and every month after TFA for 1 year. A total of 77 patients (43%) were defined as compliant. They followed all recommendations, including >80% drug intake (anti-diabetic, antihypertensive drugs, dual antiplatelet and statin treatment), healthy diet, smoking cessation, physical exercise ≥30 min/day. A total of 102 patients (57%) were non-compliant (drug intake ≤80%, and did not fully follow lifestyle change recommendations). Results There were no significant differences at baseline between the two groups. Fuster-BEWAT score in 1 year was 9.83 ± 3.1 in compliant and 7.74 ± 2.9 in non-compliant patients ( p = 0.0001). At 1-year follow-up, there were 43 myocardial infarctions (40 patients (93%) were non-compliant) and 28 deaths (26 cases (92.8%) were non-compliant). Patients from the non-compliant group with three- and two-vessel obstructive CAD had higher 1-year MACE rate than those with one-vessel obstructive and non-obstructive CAD (95.24% and 70.5% versus 17.2% and 8.6%; p < 0.0001); more proximal coronary lesions were related to a worse prognosis. Conclusions Non-compliant diabetic patients had a tenfold increased risk for MACE within 1 year after TFA.

Influence of wound scores and microbiology on the outcome of the diabetic foot syndrome

AIMS

To establish if the microbiology and the TEXAS, PEDIS and Wagner wound classifications of the diabetic foot syndrome (DFS) predict amputation.

METHODS

Prospective cohort study of 250 patients with DFS from 2009 to 2013. Tissue samples for culture were obtained and wound classification scores were recorded at admission.

RESULTS

Infection was monomicrobial in 131 patients (52%). Staphylococcus aureus was the most frequent pathogen (76 patients, 30%); being methicillin-resistant S. aureus in 26% (20/76) Escherichia coli and Enterobacter faecalis were 2nd and 3rd most frequent pathogens. Two hundred nine patients (85%) needed amputation being major in 25 patients (10%). The three wound scales associated minor amputation but did not predict this outcome. Predictors of minor amputation in the multivariate analysis were the presence of osteomyelitis, the location of the wound in the forefoot and of major amputation elevated C reactive proteine (CRP) levels. A low ankle-brachial index (ABI) predicted major amputation in the follow-up. Overall, 74% of gram-positives were sensitive to quinolones and 98% to vancomycin and 90% of gram-negatives to cefotaxime and 95% to carbapenems.

CONCLUSIONS

The presence of osteomyelitis and the location of the wound in the forefoot predict minor amputation and elevated CRP levels predict major amputation. In the follow-up a low ABI predicts major amputation.

Endovascular revascularization for patients with critical limb ischemia: impact on wound healing and long term clinical results in 189 limbs

Objective

To evaluate the impact on wound healing and long-term clinical outcomes of endovascular revascularization in patients with critical limb ischemia (CLI).

Materials and Methods

This is a retrospective study on 189 limbs with CLI treated with endovascular revascularization between 2008 and 2010 and followed for a mean 21 months. Angiographic outcome was graded to technical success (TS), partial failure (PF) and complete technical failure. The impact on wound healing of revascularization was assessed with univariate analysis and multivariate logistic regression models. Analysis of long-term event-free limb survival, and limb salvage rate (LSR) was performed by Kaplan-Meier method.

Results

TS was achieved in 89% of treated limbs, whereas PF and CF were achieved in 9% and 2% of the limbs, respectively. Major complications occurred in 6% of treated limbs. The 30-day mortality was 2%. Wound healing was successful in 85% and failed in 15%. Impact of angiographic outcome on wound healing was statistically significant. The event-free limb survival was 79.3% and 69.5% at 1- and 3-years, respectively. The LSR was 94.8% and 92.0% at 1- and 3-years, respectively.

Conclusion

Endovascular revascularization improve wound healing rate and provide good long-term LSRs in CLI.

Structured health care for subjects with diabetic foot ulcers results in a reduction of major amputation rates

Objective

We tested the effects of structured health care for the diabetic foot in one region in Germany aiming to reduce the number of major amputations.

Research design and methods

In a prospective study we investigated patients with diabetic foot in a structured system of outpatient, in-patient and rehabilitative treatment. Subjects were recruited between January 1^st, 2000 and December 31, 2007. All participants underwent a two-year follow-up. The modified University of Texas Wound Classification System (UT) was the basis for documentation and data analysis. We evaluated numbers of major amputations, rates of ulcer healing and mortality. In order to compare the effect of the structured health care program with usual care in patients with diabetic foot we evaluated the same parameters at another regional hospital without interdisciplinary care of diabetic foot (controls).

Results

684 patients with diabetic foot and 508 controls were investigated. At discharge from hospital 28.3% (structured health care program, SHC) vs. 23.0% (controls) of all ulcers had healed completely. 51.5% (SHC) vs. 49.8% (controls) were in UT grade 1.

Major amputations were performed in 32 subjects of the structured health care program group (4.7%) vs. 110 (21.7%) in controls (p<0.0001). Mortality during hospitalization was 2.5% (SHC) vs. 9.4% in controls (p<0.001).

Conclusions

With the structured health care program we achieved a significant reduction of major amputation rates by more than 75% as compared to standard care.

Amniotic mesenchymal stem cells enhance wound healing in diabetic NOD/SCID mice through high angiogenic and engraftment capabilities

Although human amniotic mesenchymal stem cells (AMMs) have been recognised as a promising stem cell resource, their therapeutic potential for wound healing has not been widely investigated. In this study, we evaluated the therapeutic potential of AMMs using a diabetic mouse wound model. Quantitative real-time PCR and ELISA results revealed that the angiogenic factors, IGF-1, EGF and IL-8 were markedly upregulated in AMMs when compared with adipose-derived mesenchymal stem cells (ADMs) and dermal fibroblasts. In vitro scratch wound assays also showed that AMM-derived conditioned media (CM) significantly accelerated wound closure. Diabetic mice were generated using streptozotocin and wounds were created by skin excision, followed by AMM transplantation. AMM transplantation significantly promoted wound healing and increased re-epithelialization and cellularity. Notably, transplanted AMMs exhibited high engraftment rates and expressed keratinocyte-specific proteins and cytokeratin in the wound area, indicating a direct contribution to cutaneous closure. Taken together, these data suggest that AMMs possess considerable therapeutic potential for chronic wounds through the secretion of angiogenic factors and enhanced engraftment/differentiation capabilities.

Evaluation of Feasibility of Ankle Pressure and Foot Oxymetry Values for the Detection of Critical Limb Ischemia in Diabetic Patients

A total of 261 diabetic patients were admitted because of rest pain and/or foot ulcer in 1 limb. Ankle pressure (AP) and transcutaneous oxygen tension (TcPO2) were measured, and digital subtraction arteriography was performed. Transcutaneous oxygen tension was <30 mm Hg in 213 patients and ≥30<50 mm Hg in 48 patients. Ankle pressure could not be measured in 109 patients. In 50 patients, AP was <70 mm Hg and in 102 patients, it was ≥70 mm Hg. Arteriography showed evidence of stenoses >50% of vessel lumen diameter in all patients. Major amputation was performed in 16 patients; AP was <70 mm Hg in 4 patients and ≥70 mm Hg in 6. It was not practicable in the remaining 6 patients. Transcutaneous oxygen tension was <30 mm Hg in 15 patients and ≥30 mm Hg in 1 patient. For diagnosis of critical limb ischemia (CLI) in diabetic patients presenting with rest pain or foot ulcer, measurement of TcPO 2 is essential not only when AP is not measurable but also when this value is ≥70 mm Hg.

Human CD133+ progenitor cells promote the healing of diabetic ischemic ulcers by paracrine stimulation of angiogenesis and activation of Wnt signaling

We evaluated the healing potential of human fetal aorta-derived CD133(+) progenitor cells and their conditioned medium (CD133(+) CCM) in a new model of ischemic diabetic ulcer. Streptozotocin-induced diabetic mice underwent bilateral limb ischemia and wounding. One wound was covered with collagen containing 2x10(4) CD133(+) or CD133(-) cells or vehicle. The contralateral wound, covered with only collagen, served as control. Fetal CD133(+) cells expressed high levels of wingless (Wnt) genes, which were downregulated following differentiation into CD133(-) cells along with upregulation of Wnt antagonists secreted frizzled-related protein (sFRP)-1, -3, and -4. CD133(+) cells accelerated wound closure as compared with CD133(-) or vehicle and promoted angiogenesis through stimulation of endothelial cell proliferation, migration, and survival by paracrine effects. CD133(+) cells secreted high levels of vascular endothelial growth factor (VEGF)-A and interleukin (IL)-8. Consistently, CD133(+) CCM accelerated wound closure and reparative angiogenesis, with this action abrogated by co-administering the Wnt antagonist sFRP-1 or neutralizing antibodies against VEGF-A or IL-8. In vitro, these effects were recapitulated following exposure of high-glucose-primed human umbilical vein endothelial cells to CD133(+) CCM, resulting in stimulation of migration, angiogenesis-like network formation and induction of Wnt expression. The promigratory and proangiogenic effect of CD133(+) CCM was blunted by sFRP-1, as well as antibodies against VEGF-A or IL-8. CD133(+) cells stimulate wound healing by paracrine mechanisms that activate Wnt signaling pathway in recipients. These preclinical findings open new perspectives for the cure of diabetic ulcers.

Efficacy and efficiency of a streamlined multidisciplinary foot ulcer service

The structure of a multidisciplinary foot care service was modified to ensure that patient consultations were only attended by the relevant team members. This audit showed the streamlined service still achieved excellent patient outcomes.

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

AIMS

We analyze mortality of first-time diabetic amputees by stratifying by level of amputation, differentiating short-term and long-term mortality.

METHODS

We evaluated 277 diabetic patients who received their first lower extremity amputation (LEA) during 1993-97. Subjects were followed until December 2003, and categorized by level of amputation. We compared the mortality difference by level for 0-10 years, 0-10 months, and 10 months-10 years, and examined the association of comorbid conditions and death for each level.

RESULTS

We found a significant difference in mortality by amputation level for 0-10 years (p<0.05) and <10 months (p<0.01) survival, but not for the one of 10 months-10 years. For major amputees deceased within 10 months, sepsis was as frequent a cause of death as cardiovascular disease. In distal amputees, CVD, CAD and ESRD were strongly associated with death, but only CAD was associated death among major amputees.

CONCLUSION

For diabetic patients undergoing first LEAs, the mortality of major amputees was worse than that of minor amputees due to the difference in first 10-month mortality. The history of comorbid conditions in first-time major amputees was less important than in minor amputees since sepsis was the frequent cause of death in major amputees in this early period.

The association between baseline characteristics and the outcome of foot lesions in a UK population with diabetes

AIMS

To explore the relationships between time to healing of diabetic foot ulcers and baseline characteristics of both patients and their ulcers.

METHODS

All patients were included who were referred to a specialist clinic over a 4-year period. Age, gender, type and duration of diabetes, ulcer site, ulcer duration and baseline characteristics were recorded. Postcode was used to derive an index of social deprivation. Patients were followed up to 1 year. The primary outcome measure was time to healing. Those who died or had an ulcer-related amputation were censored at the time of death or amputation and classified as unhealed.

RESULTS

Mean age of 449 participants (63.7% male) was 66.7 years; 42.7% had evidence of peripheral arterial disease, and 80% had peripheral neuropathy. Median ulcer duration at presentation was 29 days; 60.5% ulcers had an area of < 1 cm(2) and 68.3% of all ulcers healed without amputation during the follow-up period. Univariate analysis revealed dose-response relationships between time to healing and increasing duration of diabetes, increasing ulcer area, ulcer site and peripheral arterial disease. No associations were found with age, gender, diabetes type, deprivation index, peripheral neuropathy or infection. The relationship between healing time and ulcer area, peripheral arterial disease and diabetes duration remained significant on multivariate analysis.

CONCLUSIONS

The dominant factors influencing healing are cross-sectional area at presentation and the degree of peripheral arterial disease. Further work is needed to define how those at greatest risk may be identified and best managed.

When is a technically successful peripheral angioplasty effective in preventing above-the-ankle amputation in diabetic patients with critical limb ischaemia?

AIM

To determine parameters predictive of avoidance of major (above-the-ankle) amputation after a technically successful peripheral angioplasty (PTA) in patients with diabetes with critical limb ischaemia.

METHODS

From January 1999 to December 2003, 420 consecutive patients with diabetes admitted to hospital because of critical limb ischaemia underwent peripheral angiography and concomitant technically successful PTA. Transcutaneous oxygen tension (TcPO(2)) was measured before and after PTA. Major amputation at 30 days was recorded.

RESULTS

After PTA, the iliac-femoral-popliteal axis was patent in all patients. In 67 patients, all three crural arteries were patent, in 143 patients 2 crural arteries were patent, and in 186 patients one crural artery was patent (104 peroneal, 62 anterior tibial, 20 posterior tibial). In 24 patients, all three crural arteries were occluded. Twenty-two major amputations were performed. Of these, 15 were performed in the 24 patients with occlusion of all the infrapopliteal arteries. Seven of the 186 patients in whom only the peroneal artery was patent required amputation. In patients not requiring amputation, TcPO(2) increased from 15.5 +/- 11.9 to 45.0 +/- 12.0 mmHg (P = 0.000), while in those requiring amputation, TcPO(2) increased from 9.6 +/- 7.7 to 18.6 +/- 8.1 mmHg (P < 0.082). Multivariate analysis indicated an independent role of occlusion of infrapopliteal arteries after PTA (OR 8.20 for every crural obstructed artery, P = 0.022, CI 1.35-49.6) and TcPO(2) after PTA (OR 0.80 for increase of 1 mmHg, P < 0.001, CI 0.74-0.88).

CONCLUSIONS

In patients with diabetes, PTA is effective in avoiding major amputation, provided recanalization occurs in at least one tibial artery down to the foot. In a few patients, re-canalization of the peroneal artery alone is not sufficient to avoid major amputation.

The role of early surgical debridement and revascularization in patients with diabetes and deep foot space abscess: retrospective review of 106 patients with diabetes

One hundred-six patients underwent emergency debridement of a deep foot space abscess. While 43 patients were admitted after an outpatient visit with immediate surgical debridement (group A), 63 patients were transferred from other hospitals after a mean stay of 6.2+/-7.5 days without debridement (group B). No significant differences were observed in the demographic and clinical features between the 2 groups, except for the following differences in group B: higher blood glucose level on admission (P=.015), lower serum albumin level (P=.005), and a more frequent extension of the infection to the heel (P=.005). Eradication of the infection was obtained in group A without amputation in 9 patients, with an amputation of 1 or more rays in 21, with metatarsal amputations in 12, and with a Chopart amputation in 1. In group B, incision and drainage alone were performed in 4 patients, amputation of 1 or more rays in 21, metatarsal amputations in 10, Chopart amputations in 23, and an above-the-ankle amputation in 5. The amputation level was significantly more proximal in group B (chi2=24.4, P<.001). There was no significant difference in the presence of peripheral arterial occlusive disease between the 2 groups (P=.841). Regression logistic analysis showed a significant relationship between the amputation level and the number of days elapsed before debridement (odds ratio, 1.61; P=.015; confidence interval, 1.10-2.36), but not with the presence of peripheral occlusive disease (odds ratio, 1.73; P=.376; confidence interval, 0.29-15.3). These data show that a delay in the surgical debridement of a deep space abscess increases the amputation level. Accuracy in the diagnosis of peripheral occlusive disease and immediate revascularization yield similar outcomes in patients with or without peripheral occlusive disease.

Early and five-year amputation and survival rate of diabetic patients with critical limb ischemia: data of a cohort study of 564 patients

OBJECTIVE

To evaluate the early and late major amputation and survival rates and related risk factors in diabetic patients with critical limb ischemia (CLI).

DESIGN

Retrospective study.

METHODS

Revascularization feasibility, major amputation, survival rate and related risk factors were recorded in 564 diabetic patients consecutively hospitalized for CLI from 1999 to 2003 and followed until June 2005.

RESULTS

Peripheral angioplasty (PTA) was carried out in 420 (74.5%), bypass graft (BPG) in 117 (20.7%) patients. In 27 (4.8%) patients both PTA and BPG were not possible. Twenty-three above-the-ankle amputations (4.1%) were performed at 30 days: 6 in PTA patients, 3 in BPG patients, 14 in non revascularized patients. In the follow-up of 558 patients (98.9%), 62 repeated PTAs and 9 new BPGs, 32 new major amputations (16 in PTA patients, 14 in BPG patients and 2 in non-revascularized patients) were performed. Major amputation was associated with absence of revascularization (OR 35.9, p < 0.001, CI 12.9-99.7), occlusion of each of the three crural arteries (OR 8.20, p = 0.022, CI 1.35-49.6), wound infection (OR 2.1, p = 0.004 CI 1.3-3.6), dialysis (OR 4.7, p = 0.001 CI 1.9-11.7) increase in TcPO2 after revascularization (OR 0.80, p < 0.001 CI 0.74-0.87). One hundred seventy three patients died during follow-up and this was associated with age (HR 1.05, p < 0.001 CI 1.03-1.07), history of cardiac disease (HR 2.16, p < 0.001 CI 1.53-3.06), dialysis (HR 3.52, p < 0.001 CI 2.08-5.97), absence of revascularization (HR 1.68, p < 0.001, CI 1.29-2.19) and impaired ejection fraction (HR 1.08, p < 0.001, CI 1.05-1.09).

CONCLUSIONS

In diabetic patients with CLI the revascularization is feasible in most cases and allows a low rate of early major amputation. This rate is higher in the follow-up period. Major amputation is very high in patients where revascularization is not feasible while the high mortality rate is due to the serious comorbidities observed in these patients.

Risk factors for major limb amputations in diabetic foot gangrene patients

We analyzed the clinical picture of diabetic foot lesion patients to investigate the risk factors for major limb amputations. The subjects were 210 diabetic foot lesion patients treated at our department over the past 9 years. The mean follow-up period was 604.5 [standard deviation (S.D.) 451.2] days with a median value of 492 days. There were 113 men and 97 women. By the final follow-up day, 18 underwent bypass surgeries (9%) and 13 skin grafts (6%), while 110 patients (52%) finally required limb amputation. The breakdown was 45 major amputations above or below the knee and 65 minor amputations of the toes or metatarsals. The outcomes of the major amputations were retrospectively analyzed by group. The blood glucose control was poor in all 45 major amputees, and their mean HbA1c (8.80%) was higher than that in the minor or non-amputation group (7.79%, P = 0.035). In the major amputation group, two patients had loss of vision due to retinopathy, and 30 patients received long-term hemodialysis due to nephropathy. The rate of arteriosclerosis obliterans (ASO) was higher in the major amputation group than in the minor or non-amputation group, and arteriography showed significantly high rates of multiple stenosis. Multivariate analysis of these results by the proportional hazard model showed that ASO with multiple stenosis (hazard ratio 3.23, 95% CI: 1.12-5.10), hemodialysis (2.14, 95% CI: 1.17-3.44), and HbA1c (1.20, 95% CI: 1.03-1.41) were independent risk factors for major amputation. The 3-year survival rate was 24.1% in the major amputation group and 93.0% in the minor or non-amputation group, and the life expectancy was significantly lower for the major amputees than the minor or non-amputees (P<0.0001). Together with early detection and treatment of foot lesions, good blood glucose control and early management of systemic complications such as nephropathy and arteriosclerosis are considered important to avoid major amputations.

Trends in the Presentation and Surgical Management of the Acute Diabetic Foot

BACKGROUND

This study examines trends in the presentation and surgical management of acute diabetic foot problems in a single institution.

METHOD

Prospective audit of all diabetic patients who had a primary procedure for critical lower limb ischaemia (CLI) and/or foot sepsis between 1st January 1990 and 31st December 2002. Primary and secondary intervention, mortality and limb salvage rate within 6 weeks of the index procedure were recorded.

RESULTS

There were 661 patients (417 men and 244 women of median age 69, range 31-99, years) with 799 affected limbs. CLI alone was present in 625 (78%) limbs, combined CLI and foot sepsis in 53 (7%) and foot sepsis alone in 121 (15%). The primary intervention was minor amputation in 323 (40%) limbs, revascularisation in 288 (36%), major amputation in 185 (23%) and sympathectomy in three limbs. Within 6 weeks, 125 (16%) limbs required secondary intervention, the peri-procedural mortality rate was 38 of 924 (4%), and the limb salvage rates for patients with CLI, combined CLI and sepsis and sepsis alone were 66, 66 and 80%, respectively. There was a significant decline in the proportion of patients presenting with CLI alone and a significant increase in the proportion presenting with combined CLI and sepsis and sepsis alone. In patients with CLI alone, there was a significant increase in the primary major amputation rate and a significant decline in the minor amputation rate with no significant change in the revascularisation rate.

CONCLUSION

There has been a progressive decline in the proportion of patients presenting with CLI alone and a greater proportion of patients presenting with an element of foot sepsis. In patients with CLI alone, the primary major amputation rate has increased at the expense of a decline in minor amputation rate.

Amputation in Diabetic Patients

BACKGROUND

Foot ulcers and their complications are an important cause of morbidity and mortality in diabetes. The present study examines the amputation risk criterion and the long term outcome in terms of amputations and mortality in patients with diabetic foot.

METHODS

27 patients with diabetic foot lesions were studied. There were 15 patients with early lesions and 10 with advanced lesions. 15 patients were managed conservatively including local amputations and 12 with lower extremity amputations. 80% patients were males in 45-59 years of age group and all patients had more than 6 years of poorly controlled diabetes.

RESULTS

Precipitating factors included walking barefoot, history of minor trauma, infection, callosities or burns in 86% of patients. Major lower limb amputations were common in irregularly treated, poorly controlled diabetics due to infection in a limb devitalized by angiopathy and desensitised by neuropathy.

CONCLUSION

Diabetic foot ulcers are associated with high morbidity and mortality. Mortality was higher in ischaemic ulcers than neuropathic ulcers.

Mortality in diabetic and nondiabetic patients after amputations performed from 1990 to 1995: a 5-year follow-up study

OBJECTIVE

To compare survival rates after first amputation between patients with and without diabetes. RESEARCH DESIGN AAND METHODS: We performed a retrospective study of all nontraumatic amputations performed at our center in the years 1990-1995 in patients with (n = 100) and without (n = 151) diabetes. Survival status was assessed from the first amputation until 31 December 2001.

RESULTS

Altogether, 61% of the patients with and 54.3% of those without diabetes died 5.2 (4.5-5.8) and 5.3 (4.7-5.9) [mean (95% CI)] years after the first amputation, respectively (P = 0.80). Survival was not different between patients with and without diabetes after controlling for the level (major versus minor) (P = 0.67) or the cause (ischemia versus infection) of amputation (P = 0.72). No sex differences were found for survival in either study group. Independent predictors of mortality in the diabetic group were duration of diabetes (P = 0.05), history of stroke (P = 0.02), and serum creatinine level (P < 0.0001), while in the nondiabetic group independent predictors were history of stroke (P = 0.04), serum creatinine level (P = 0.005), and higher white blood cell count (P = 0.02). The peak incidence of amputations was observed in the decade of 67-76 years of age in both groups. Major amputations were more common among nondiabetic patients in all age-groups. Median hospital stay and postoperative complications were comparable between the two groups.

CONCLUSIONS

All-cause mortality is high after an amputation in both diabetic and nondiabetic patients. Mortality rates, hospital stay, and postoperative complications are not different between diabetic and nondiabetic amputees. No modifiable factors, with the exception of nephropathy, were found to improve survival in amputees. Peripheral vascular disease and neuropathy are the main cause of amputations; prevention, therefore, of these complications is warranted to prevent amputations and the subsequent high mortality.

Amputation and mortality in new-onset diabetic foot ulcers stratified by etiology

OBJECTIVE

Foot ulcers and their complications are an important cause of morbidity and mortality in diabetes. The present study aims to examine the long-term outcome in terms of amputations and mortality in patients with new-onset diabetic foot ulcers in subgroups stratified by etiology.

RESEARCH DESIGN AND METHODS

Patients presenting with new ulcers (duration <1 month) to a dedicated diabetic foot clinic between 1994 and 1998 were studied. Outcomes were determined until March 2000 (or death) from podiatry, hospital, and district registers. Baseline clinical examination was done to classify ulcers as neuropathic, ischemic, or neuroischemic. Five-year amputation and mortality rates were derived from Kaplan-Meier survival analysis curves.

RESULTS

Of the 185 patients studied, 41% had peripheral vascular disease (PVD) and 61% had neuropathy; 45%, 16%, and 24% of patients had neuropathic, ischemic, and neuroischemic ulcers, respectively. The mean follow-up period was 34 months (range 1-65) including survivors and patients who died during the study period. Five-year amputation rates were higher for ischemic (29%) and neuroischemic (25%) than neuropathic (11%) ulcers. Five-year mortality was 45%, 18%, and 55% for neuropathic, neuroischemic, and ischemic ulcers, respectively. Mortality was higher in ischemic ulcers than neuropathic ulcers. On multivariate regression analysis, only increasing age predicted shorter survival time.

CONCLUSIONS

All types of diabetic foot ulcers are associated with high morbidity and mortality. The increased mortality appears to be independent of factors increasing ulcer risk-that is, neuropathy and PVD-in patients with established foot ulcers.