Lower-limb revascularization and major amputation rates in England

Risk Factors for Mortality and Promoting Factors for Ambulation After Major Lower Limb Amputation for End-Stage Arterial Disease: A Multicenter Study

BACKGROUND

Around 1%-2% of patients with peripheral arterial disease will require a lower limb amputation at some point. Despite advancements in prevention and treatment, mortality after major amputation remains high. The aim of this study was to investigate the risk factors related to mortality and promoting factors for ambulation postamputation.

METHODS

A multicenter retrospective study of consecutive major lower limb amputation patients performed at the department of thoracic and vascular surgery of the University Hospitals Ghent and Leuven between January 2008 and December 2017.

RESULTS

Three hundred and thirteen patients met the inclusion criteria. Overall, 1-year mortality rate was 29.7% with age being the most important risk factor. Above-knee amputations had significantly higher mortality (37%) than below-knee amputations (22%) at 1 year. Diabetes and number of vascular interventions were not linked to higher mortality. Age, amputation level, and presence of hypertension were the most important determining factors for successful ambulation.

CONCLUSIONS

Maintaining the independency of patients, whether this is obtained by maximizing limb salvage or primary amputation, is critical. Knowledge about the factors that play a role in the risk of death and the chance of regaining ambulation is important to include in the decision-making conversation with the patient.

Illness Trajectories After Revascularization in Patients With Peripheral Artery Disease: A Unified Approach to Understanding the Risk of Major Amputation and Death

BACKGROUND

The aim of this study was to investigate the illness trajectories of patients with peripheral artery disease (PAD) after revascularization and estimate the independent risks of major amputation and death (from any cause) and their interaction.

METHODS

Data from Hospital Episode Statistics Admitted Patient Care were used to identify patients (≥50 years of age) who underwent lower limb revascularization for PAD in England from April 2013 to March 2020. A Markov illness-death model was developed to describe patterns of survival after the initial lower limb revascularization, if and when patients experienced major amputation, and survival after amputation. The model was also used to investigate the association between patient characteristics and these illness trajectories. We also analyzed the relative contribution of deaths after amputation to overall mortality and how the risk of mortality after amputation was related to the time from the index revascularization to amputation.

RESULTS

The study analyzed 94 690 patients undergoing lower limb revascularization for PAD from 2013 to 2020. The majority were men (65.6%), and the median age was 72 years (interquartile range, 64-79). One-third (34.8%) of patients had nonelective revascularization, whereas others had elective procedures. For nonelective patients, the amputation rate was 15.2% (95% CI, 14.4-16.0) and 19.9% (19.0-20.8) at 1 and 5 years after revascularization, respectively. For elective patients, the corresponding amputation rate was 2.7% (95% CI, 2.4-3.1) and 5.3% (4.9-5.8). Overall, the risk of major amputation was higher among patients who were younger, had tissue loss, diabetes, greater frailty, nonelective revascularization, and more distal procedures. The mortality rate at 5 years after revascularization was 64.3% (95% CI, 63.2-65.5) for nonelective patients and 33.0% (32.0-34.1) for elective patients. After major amputation, patients were at an increased risk of mortality if they underwent major amputation within 6 months after the index revascularization.

CONCLUSIONS

The illness-death model provides an integrated framework to understand patient outcomes after lower limb revascularization for PAD. Although mortality increased with age, the study highlights patients <60 years of age were at increased risk of major amputation, particularly after nonelective revascularization.

Clinical Effects of Tourniquet Use for Nontraumatic Major Lower Limb Amputation: A Two-Center Retrospective Cohort Study

BACKGROUND

To investigate the effect of tourniquet use on outcomes after major lower limb amputation (MLLA) due to peripheral arterial disease or complications from diabetes mellitus.

METHODS

In this 2-center retrospective observational study, vascular patients who underwent MLLA between January 1, 2016 and December 31, 2020 at 2 UK hospitals were identified using operating theater databases. Hospital databases were used to access medical records, operation notes, and laboratory reports. The use of a tourniquet in each MLLA was noted. The primary outcome was postoperative hemoglobin (Hb) drop (g/L). Secondary outcomes were units of allogeneic blood transfused perioperatively, 90-day revision rates, 90-day wound breakdown rates, surgical site infection (SSI) rates (at 30 days), and 90-day mortality. A follow-up index (a measure of follow-up completeness) was calculated for all 30-day and 90-day outcomes.

RESULTS

Four hundred seventy two patients underwent MLLA, of which 124 had a tourniquet applied. The median postoperative Hb drop was significantly lower in the tourniquet group compared to the nontourniquet group (13 [interquartile range 5-22] g/L vs. 20 [interquartile range 11-28] g/L; P ≤ 0.001). Thirty three point one percent (41) of tourniquet patients received a blood transfusion perioperatively, compared to 35.6% (124) of nontourniquet patients (P = 0.82). Sixteen percent (76) of patients required surgical revision within 90 days, with no significant difference between the tourniquet and nontourniquet group (20.2% tourniquet vs. 14.7% no tourniquet; P = 0.15). SSI rates (12.0% tourniquet vs. 10.6% no tourniquet, P = 0.66) and 90-day mortality (6.5% tourniquet vs. 10.1% no tourniquet; P = 0.23) were similar. Multivariable regression demonstrated that tourniquet use was independently associated with a reduced hemoglobin drop (β = -4.671, 95% confidence interval -7.51 to -1.83, P ≤ 0.001) but was not associated with wound breakdown, revision surgery, or SSI. Hypertension, SSI, and below-knee amputation using the skew flap technique were all significant predictors of revision surgery. All follow-up indices were ≥ 0.97.

CONCLUSIONS

Tourniquet use in MLLA was associated with a significantly lower fall in postoperative Hb without evidence of harm in terms of SSI, wound breakdown/revision rates, or mortality.

The prevalence of major lower limb amputation in the diabetic and non-diabetic population of England 2003-2013

AIMS

To determine the prevalence of amputation and revascularisation among diabetics and non-diabetics between 2003 and 2013.

METHODS

Retrospective analysis of English hospital data with census estimates for population aged 50-84 years.

RESULTS

There were 42,294 major and 52,525 minor amputations and 355,545 revascularisations. Major amputation rates fell by 20% (27.7-22.9), with minor amputations (22.9-35.2) and revascularisations (199.8-245.4) rising. The major amputation rate reduced in diabetics (men, 180.5-111.8; women, 92.8-52.7) faster than non-diabetics (men, 24.6-18.7; women, 11.0-8.9). In total, 48.2% of men and 58.0% of women amputees were not diabetic.

CONCLUSION

Diabetics continue to experience six times the rate of amputation than non-diabetics. However, half of major amputees were not diabetic and experienced slower rates of decrease. Non-diabetics, particularly those with peripheral arterial disease, should have access to appropriate services, particularly foot care.

Temporal changes in the prevalence and associates of diabetes-related lower extremity amputations in patients with type 2 diabetes: the Fremantle Diabetes Study

Background

To determine temporal changes in the prevalence and associates of lower extremity amputation (LEA) complicating type 2 diabetes.

Methods

Baseline data from the longitudinal observational Fremantle Diabetes Study (FDS) relating to LEA and its risk factors collected from 1296 patients recruited to FDS Phase 1 (FDS1) from 1993 to 1996 and from 1509 patients recruited to FDS Phase 2 (FDS2) from 2008 to 2011 were analysed. Multiple logistic regression was used to determine associates of prevalent LEA in individual and pooled phases. Generalised linear modelling was used to examine whether diabetes related LEA prevalence and its associates had changed between Phases.

Results

There were 15 diabetes-related LEAs at baseline in FDS1 (1.2 %) and 15 in FDS2 (1.0 %; P = 0.22 after age, sex and race/ethnicity adjustment). In multivariable analysis, independent associates of a baseline LEA in FDS1 were a history of vascular bypass surgery or revascularisation, urinary albumin:creatinine ratio, peripheral sensory neuropathy and cerebrovascular disease (P ≤ 0.035). In FDS2, prevalent LEA was independently associated with a history of vascular bypass surgery or revascularisation, past hospitalisation for/current foot ulcer and fasting serum glucose (P ≤ 0.001). In pooled analyses, a history of vascular bypass or revascularisation, past hospitalisation for/current foot ulcer at baseline, urinary albumin:creatinine ratio (P < 0.001), as well as FDS Phase as a binary variable [odds ratio (95 % confidence interval): 0.28 (0.09–0.84) for FDS2 vs FDS1, P = 0.023] were associated with a lower risk of LEA at study entry.

Conclusions

The risk of prevalent LEA in two cohorts of patients with type 2 diabetes from the same Australian community fell by 72 % over a 15-year period after adjustment for important between-group differences in diabetes-related and other variables. This improvement reflects primary care foot health-related initiatives introduced between Phases, and should have important individual and societal benefits against a background of a progressively increasing diabetes burden.

Temporal changes in the prevalence and associates of foot ulceration in type 2 diabetes: the Fremantle Diabetes Study

AIMS

To assess temporal changes in foot ulceration and its risk factors in community-based people with type 2 diabetes.

METHODS

Baseline data from the longitudinal observational Fremantle Diabetes Study collected from 1993 to 1996 (Phase I) and 2008 to 2011 (Phase II) were analyzed. Generalized linear modeling was used to examine changes in foot ulcer prevalence and its associates between phases. Multiple logistic regression was used to determine associates of prevalent foot ulceration in individual and pooled phases.

RESULTS

There were 16 foot ulcers among 1296 patients in Phase I (1.2%) and 23 in 1509 Phase II patients (1.5%; P=0.86 after age, sex and race/ethnicity adjustment). Glycemic and non-glycemic cardiovascular risk factors were better in Phase II, but diabetes duration was longer, peripheral sensory neuropathy (PSN) was more prevalent and more patients were Aboriginal (P<0.001) than in Phase I. In multivariable analysis of both phases and pooled data, diabetes duration and peripheral sensory neuropathy (PSN) were independent associates of foot ulceration (P≤0.026). Prior hospitalization for ulcer, intermittent claudication, any absent pedal pulse and Aboriginality were also significant in the pooled model (P≤0.009).

CONCLUSIONS

Strong associations between foot ulcer and diabetes duration, PSN, symptomatic and clinically-detectable peripheral vascular disease were observed. Aboriginality also proved an independent risk factor. Since all these risk factors apart from intermittent claudication and impalpable foot pulses were more prevalent in Phase II, improved community- and hospital-based foot care between phases are likely to have attenuated the risk of foot ulcers in Phase II patients.

Lower limb amputation in Northern Netherlands: unchanged incidence from 1991-1992 to 2003-2004

BACKGROUND

Investigating population changes gives insight into effectiveness and need for prevention and rehabilitation services. Incidence rates of amputation are highly varied, making it difficult to meaningfully compare rates between studies and regions or to compare changes over time.

STUDY DESIGN

Historical cohort study of transtibial amputation, knee disarticulation, and transfemoral amputations resulting from vascular disease or infection, with/without diabetes, in 2003-2004, in the three Northern provinces of the Netherlands.

OBJECTIVES

To report the incidence of first transtibial amputation, knee disarticulation, or transfemoral amputation in 2003-2004 and the characteristics of this population, and to compare these outcomes to an earlier reported cohort from 1991 to 1992.

METHODS

Population-based incidence rates were calculated per 100,000 person-years and compared across the two cohorts.

RESULTS

Incidence of amputation was 8.8 (all age groups) and 23.6 (≥45 years) per 100,000 person-years. This was unchanged from the earlier study of 1991-1992. The relative risk of amputation was 12 times greater for people with diabetes than for people without diabetes.

CONCLUSIONS

Investigation is needed into reasons for the unchanged incidence with respect to the provision of services from a range of disciplines, including vascular surgery, diabetes care, and multidisciplinary foot clinics.

CLINICAL RELEVANCE

This study shows an unchanged incidence of amputation over time and a high risk of amputation related to diabetes. Given the increased prevalence of diabetes and population aging, both of which present an increase in the population at risk of amputation, finding methods for reducing the rate of amputation is of importance.

Quality improvement framework for major amputation: are we getting it right?

INTRODUCTION

The quality improvement framework for major amputation was developed with the aim of improving outcomes and reducing the perioperartive mortality to less than 5% by 2015. The aim of the study was to assess our compliance with the framework guidelines and look for the reasons for non-compliance.

METHOD

All major amputations performed between 2008 and 2010 were included. The following data were collected: presence of infection ± tissue loss, status of arterial supply, revascularisation attempts, time to surgery, type of amputation, morbidity and mortality.

RESULTS

A total of 81 patients were included (42 BKAs, 39 AKAs). Ninety percentage had formal preoperative arterial investigations and 84% had an attempted revascularisation procedure. Patients who were transferred late from non-vascular units (n = 12) had a 30-day mortality of 50% whereas patients who presented directly to our unit had a 30-day mortality of 7.2%. The number of amputations has decreased over the last 3 years from 34 to 21 per year, coinciding with the doubling of crural revascularisation procedures performed (from 60 to 120 per year). Ten patients underwent a revision from BKA to AKA because of an inadequate profunda femoris artery (PFA), whereas all those with a healed BKA stump either had a good PFA or a named crural vessel.

CONCLUSION

The overall number of amputations is decreasing from year to year. By doubling our crural revascularisation procedures we are saving more limbs. Thirty-day mortality is higher than expected, particularly in patients who present late. Expeditious referral may potentially improve the mortality rate among this group of patients.

Lower limb amputations in Trondheim, Norway

BACKGROUND AND PURPOSE

In the city of Trondheim, Norway, diabetic lower-limb amputations accounted for one-third of all lower-limb amputations (LLAs). In an attempt to reduce this rate, a diabetic foot team was established in 1996. We present the incidence of LLA in Trondheim as measured 10 years later.

PATIENTS AND METHODS

In 2004-07, we registered all LLAs performed in Trondheim and then compared the data with previously published data from 1994-1997. From 1996 through 2006, we registered the activity of the diabetic foot team and we also registered the number of vascular procedures performed on citizens of Trondheim from 1998 through 2006.

RESULTS

Comparing the two 3-year periods 1994-97 and 2004-07, we observed a decrease in all non-traumatic LLAs. The incidence of diabetic major LLAs per 10³ diabetics per year decreased from 4.0 to 2.4, and in patients with peripheral vascular disease we observed a decrease in LLAs from 18 to 12 per 10⁵ inhabitants per year. 5,915 consultations on diabetic subjects were conducted by the diabetic foot team during the period 1996-2006. From 1998 to 2006, the rate of vascular procedures decreased in the non-diabetic population, and was unchanged in diabetic subjects.

INTERPRETATION

In the population of Trondheim city there appears to have been a reduction in the rate of vascular obstructive lower-limb disease between the two 3-year periods 1994-97 and 2004-07. In our judgment, the decline in diabetic LLA also reflects better care of the diabetic foot.

Changes in the incidence of lower extremity amputations in individuals with and without diabetes in England between 2004 and 2008

OBJECTIVE

To describe recent trends in the incidence of nontraumatic amputations among individuals with and without diabetes and estimate the relative risk of amputations among individuals with diabetes in England.

RESEARCH DESIGN AND METHODS

We identified all patients aged >16 years who underwent any nontraumatic amputation in England between 2004 and 2008 using national hospital activity data from all National Health Service hospitals. Age- and sex-specific incidence rates were calculated using the total diabetes population in England every year. To test for time trend, we fitted Poisson regression models.

RESULTS

The absolute number of diabetes-related amputations increased by 14.7%, and the incidence decreased by 9.1%, from 27.5 to 25.0 per 10,000 people with diabetes, during the study period (P > 0.2 for both). The incidence of minor and major amputations did not significantly change (15.7-14.9 and 11.8-10.2 per 10,000 people with diabetes; P = 0.66 and P = 0.29, respectively). Poisson regression analysis showed no statistically significant change in diabetes-related amputation incidence over time (0.98 decrease per year [95% CI 0.93-1.02]; P = 0.12). Nondiabetes-related amputation incidence decreased from 13.6 to 11.9 per 100,000 people without diabetes (0.97 decrease by year [0.93-1.00]; P = 0.059). The relative risk of an individual with diabetes undergoing a lower extremity amputation was 20.3 in 2004 and 21.2 in 2008, compared with that of individuals without diabetes.

CONCLUSIONS

This national study suggests that the overall population burden of amputations increased in people with diabetes at a time when the number and incidence of amputations decreased in the aging nondiabetic population.

Bypass versus Angioplasty in Severe Ischaemia of the Leg (BASIL) trial: An intention-to-treat analysis of amputation-free and overall survival in patients randomized to a bypass surgery-first or a balloon angioplasty-first revascularization strategy

BACKGROUND

A 2005 interim analysis of the Bypass versus Angioplasty in Severe Ischaemia of the Leg (BASIL) trial showed that in patients with severe lower limb ischemia (SLI; rest pain, ulceration, gangrene) due to infrainguinal disease, bypass surgery (BSX)-first and balloon angioplasty (BAP)-first revascularization strategies led to similar short-term clinical outcomes, although BSX was about one-third more expensive and morbidity was higher. We have monitored patients for a further 2.5 years and now report a final intention-to-treat (ITT) analysis of amputation-free survival (AFS) and overall survival (OS).

METHODS

Of 452 enrolled patients in 27 United Kingdom hospitals, 228 were randomized to a BSX-first and 224 to a BAP-first revascularization strategy. All patients were monitored for 3 years and more than half for >5 years.

RESULTS

At the end of follow-up, 250 patients were dead (56%), 168 (38%) were alive without amputation, and 30 (7%) were alive with amputation. Four were lost to follow-up. AFS and OS did not differ between randomized treatments during the follow-up. For those patients surviving 2 years from randomization, however, BSX-first revascularization was associated with a reduced hazard ratio (HR) for subsequent AFS of 0.85 (95% confidence interval [CI], 0.5-1.07; P = .108) and for subsequent OS of 0.61 (95% CI, 0.50-0.75; P = .009) in an adjusted, time-dependent Cox proportional hazards model. For those patients who survived for 2 years after randomization, initial randomization to a BSX-first revascularization strategy was associated with an increase in subsequent restricted mean overall survival of 7.3 months (95% CI, 1.2-13.4 months, P = .02) and an increase in restricted mean AFS of 5.9 months (95% CI, 0.2-12.0 months, P = .06) during the subsequent mean follow-up of 3.1 years (range, 1-5.7 years).

CONCLUSIONS

Overall, there was no significant difference in AFS or OS between the two strategies. However, for those patients who survived for at least 2 years after randomization, a BSX-first revascularization strategy was associated with a significant increase in subsequent OS and a trend towards improved AFS.

Trends in lower extremity amputations in people with and without diabetes in England, 1996-2005

AIMS

To examine trends in non-traumatic lower extremity amputations over a 10-year-period in people with and without diabetes (DM) in England.

METHODS

All individuals admitted to NHS hospitals for non-traumatic amputations between 1996 and 2005 in England were identified using hospital activity data. Postoperative and 1-year mortality were examined between 2000 and 2004.

RESULTS

There was a reduction in minor and major amputations during the study period. The number of type 1 DM- and non-DM-related minor amputations decreased by 11.4% and 32.4%, respectively, while the number of type 2 DM-related minor amputations almost doubled. The incidence of type 1- and non-DM-related minor amputations decreased from 1.5 to 1.2 and from 8.1 to 5.1/100,000 population, respectively, while type 2 DM-related amputations increased from 2.4 to 4.1/100,000 population. The number of type 1- and non-DM-related major amputations declined by 41% and 22%, respectively, whereas type 2 DM-related amputations increased by 43%. The incidence of type 2 DM-related amputations increased from 2.0 to 2.7/100,000 population. Overall perioperative and 1-year mortality did not significantly change between 2000 and 2004.

CONCLUSIONS

While several factors may explain the increase in type 2 DM-related LEAs, these findings highlight the importance of diabetes prevention strategies and controlling risk factors for LEAs in people with diabetes.

Outcome of ilio-popliteal grafting for peripheral arterial disease

OBJECTIVE

Assess outcomes of ilio-politeal grafting for complex ilio-femoral atherosclerotic disease.

DESIGN

Retrospective review of patients undergoing iliopopliteal grafting between January 1998 and January 2007.

METHODS

Patients were identified from our unit database. Case notes and radiology were retrieved. Data were extracted and entered into the database for analysis.

RESULTS

19 grafts were undertaken in 19 patients. Primary graft patency was 45% at 1 year (95% CI, 22% - 68%). Secondary graft patency was 82.5% at one year (95% CI, 64% - 100%). 25 subsequent surgical and radiological interventions were undertaken in 12 patients. Lower limb amputation was rare; limb survival was 88% (95% CI, 72% - 100%) at one year and 73% (95% CI 44% - 100%) at 4 years.

CONCLUSIONS

Iliopopliteal grafts are rarely undertaken severe disease requiring their use is infrequently encountered. High mortality and low primary patency mean its use can only be advocated in exceptional circumstances.

Incidence of lower-limb amputation in the diabetic and nondiabetic general population: a 10-year population-based cohort study of initial unilateral and contralateral amputations and reamputations

OBJECTIVE

The purpose of this study was to compare the incidence of vascular lower-limb amputation (LLA) in the diabetic and nondiabetic general population.

RESEARCH DESIGN AND METHODS

A population-based cohort study was conducted in a representative Swedish region. All vascular LLAs (at or proximal to the transmetatarsal level) performed from 1997 through 2006 were consecutively registered and classified into initial unilateral amputation, contralateral amputation, or reamputation. The incidence rates were estimated in the diabetic and nondiabetic general population aged > or =45 years.

RESULTS

During the 10-year period, LLA was performed on 62 women and 71 men with diabetes and on 79 women and 78 men without diabetes. The incidence of initial unilateral amputation per 100,000 person-years was 192 (95% CI 145-241) for diabetic women, 197 (152-244) for diabetic men, 22 (17-26) for nondiabetic women, and 24 (19-29) for nondiabetic men. The incidence increased from the age of 75 years. Of all amputations, 74% were transtibial. The incidences of contralateral amputation and of reamputation per 100 amputee-years in diabetic women amputees were 15 (7-27) and 16 (8-28), respectively; in diabetic men amputees 18 (10-29) and 21 (12-32); in nondiabetic women amputees 14 (7-24) and 18 (10-28); and in nondiabetic men amputees 13 (6-22) and 24 (15-35).

CONCLUSIONS

In the general population aged > or =45 years, the incidence of vascular LLA at or proximal to the transmetatarsal level is eight times higher in diabetic than in nondiabetic individuals. One in four amputees may require contralateral amputation and/or reamputation.