A pproximately 60,000 nontraumatic diabetic amputation procedures are performed annually in the United States.1,2 The risk of a patient with diabetes succumbing to a nontraumatic lower-extremity amputation is 5% to 15%. This risk represents a 15-fold increase in contrast to the nondiabetic population. Medical professionals are rigorously searching for reasons to explain this phenomenon in order to reduce this risk of amputation.3
The literature reports risk factors predisposing patients with diabetes to limb loss. Reiber et al.4 identified specific risk factors asserted to increase the chances for nontraumatic amputation. These risks include increased age, male gender, African-American race, presence of neuropathy and/or peripheral vascular disease (PVD), type of diabetes (greater risk in noninsulin-dependent diabetes mellitus), poor glycemic control including elevated hemoglobin (Hgb) A1C level, clinical duration of diabetes, and prior history of ulcers, retinopathy, and previous amputations.4 In an earlier article, Reiber et al.5 presented pathophysiologic risk factors for lower-extremity amputation including presence of neuropathy, PVD, hypertension, smoking, hyperlipidemia, propensity for infection secondary to trauma, ulcers, and ingrown nails. Data provided evidence that 80% to 85% of lower-extremity amputations are the result of chronic ulcerations and faulty wound healing.6,7 Therefore, physiologic parameters of poor wound healing, such as poor plasma albumin and low plasma zinc levels, have also been identified as risk factors for nontraumatic amputation in patients with diabetes.5
In a continuing effort to better understand factors precipitating amputation in patients with diabetes, various paradigms have been developed. As a result, “causal pathways” relating various common risk factors have been described. These pathways incorporate the major risk factors of ischemia and neuropathy with specific component causes and sufficient causes of amputation.8 Component causes of amputation include trauma, ulceration, and/or failure to heal, whereas sufficient causes include gangrene and infection.
A multispecialty, interdisciplinary clinic was created in 1996 at the Louisiana State University Health Sciences Center—Shreveport to address the rising number of patients with diabetes presenting with lower-extremity wounds and at risk for amputation. Despite adherence to treatment pathways addressing known risk factors increasing the risk of amputation, the rate of limb loss secondary to diabetes remained relatively unchanged over a 5-year period. The major risk factors observed in the authors’ population were similar to those previously reported in the literature.4–7 However, the authors observed many patients with diabetes who possessed the major risk factors of neuropathy and PVD yet did not develop any component causes, such as trauma, ulceration, and/or failure to heal.
Furthermore, many patients with confirmed component causes did not advance to major lower-limb amputations. The underlying factors that protected these patients with diabetes and risk factors of neuropathy and/or PVD from limb loss were unknown. Therefore, it was the intent of this investigation to identify additional factors differentiating those patients with diabetes who advanced to amputation from those with similar risk factors who did not succumb to amputation.

Research Design and Methods

The design of this study was a retrospective, exploratory data analysis using existing patient information from the institutional patient records. The records of 50 patients with diabetes and documented presence of the major risk factors neuropathy and/or PVD that had undergone major lower-extremity amputations between 1997 and 2002 and 30 patients with diabetes who likewise had neuropathy and/or PVD but had not undergone major limb loss were examined. The presence of neuropathy was defined as the documented absence of protective sensation based on Semmes-Weinstein monofilament testing, while the presence of PVD was defined as the documented absence of palpable dorsalis pedis and posterior tibial pulses.
In addition to documenting the presence of neuropathy and/or PVD, 2 variables, Medical Care and Patient Compliance, were created and evaluated using data contained within the patient file. Evaluation of Medical Care was predicated on documentation of 6 performance measures based on clinical guidelines recommended in a consensus statement from the American Medical Association, the Joint Commission on Accreditation of Healthcare Organizations, and the National Committee for Quality Assurance and from an Announcement from Louisiana Health Care Review, Inc. These included documentation of 1) annual lipid profile, 2) annual microalbuminuria analysis, 3) quarterly Hgb A1C analysis, 4) at least 1 diabetes education session, 5) an annual foot examination, and 6) an annual eye examination. A scoring system was devised based upon documented performance at the primary care level of tests and examinations proposed in these clinical guidelines. One point was assigned for the performance of each test or exam thus creating a maximum of 6 points and a minimum of 0. The total number of points reflected the degree of Medical Care and for this study was qualified as: Good (5–6 pts), Average (3–4 pts), and Poor (0–2 pts).
The authors created the variable Patient Compliance independent of patient health status using 4 categories that quantified the degree to which patients demonstrated responsibility in the management of their disease states. The 4 criteria used to assess compliance were 1) evidence of more than 2 missed appointments in a 1-year period, 2) failure to take medications as prescribed, 3) failure to perform wound care as directed, and 4) failure to wear protective or offweighting footwear as directed.
Each of the 4 categories reflecting compliance was considered equally important and of sufficient capacity to influence clinical outcomes. Because of this, nonadherence in any of these 4 categories was considered significant enough to identify the patient as noncompliant. Therefore, patients with evidence of at least 1 of the 4 items were considered to have Poor compliance. Those rated compliant in the 4 categories were considered to have Good compliance.

Results

In those patients that had succumbed to major lower-extremity amputations, 12% had neuropathy, 38% had PVD, and 45% had both. In this same group, Medical Care was scored as Good in 0%, Average in 8%, and Poor in 92%. Furthermore, in those patients progressing to amputation, Patient Compliance was Good in only 21%, while 79% scored Poor (see Table 1).
In contrast, of those patients with diabetes and similar major risk factors that did not progress to major lower-extremity amputations, 43% had neuropathy, 19% had PVD, and 38% had both. Medical Care was rated as Good in 28%, Average in 65%, and Poor in only 7%. Patient Compliance was rated as Good in 68% and Poor in only 32% (see Table 2).

Discussion

The pathological manifestations of diabetes resulting in decreased function and increased need for medical care can be greatly affected by the patient. In this respect, passive involvement in medical management of diabetes is not desired. In contrast, empirical data have shown that those patients with diabetes who assume more involved and active roles in the management of their disease states have improved prognoses. The findings of this investigation show that appropriate involvement in medical management of diabetes may reduce the chances of succumbing to nontraumatic amputations.
It has been estimated that patients with diabetes provide approximately 95% or more of their daily medical care.9 Thus, the demand on the patient with diabetes is considerable. Compliance, or adherence, is therefore an issue of tremendous significance if medical involvement in management of diabetes is to prove efficacious. Compliance, as defined in this study, reflected attendance of regular outpatient physician visits and demonstration of self-responsibility for key factors, such as performance of wound care, use of prescribed footwear, and medications. While there may certainly be other factors that may reflect or measure compliance, examination of those selected in this investigation revealed a surprisingly poor level of compliance in patients succumbing to amputation. It is likely that similar results would be noted with use of additional or different measures of patient compliance.
Given estimations of a 36% to 82% adherence rate for independent glucose monitoring,10 this wide range indicates that there are many patients with diabetes who simply do not recognize the importance of self-care or for whatever reasons are not able to receive the care. For patients with neuropathy, it is essential that they perform daily foot care and inspections for abnormalities. For patients with foot pathology, it is essential that they wear the prescribed protective footwear to prevent further injury or help to heal existing ulcers.
Perhaps the most surprising information revealed by this study is the finding that medical care at the primary care level is inconsistent and inadequate. The disparity between those subjects receiving Good medical care and those receiving Poor medical care, as defined by the authors’ definitions, is astounding. While the authors are unable to elaborate as to the underlying means for such a disparity, ie, why 1 patient receives good care and another patient poor care, the emphasis should be shifted to how to rectify this disparity. The authors’ qualitative assessment of Medical Care is based on previously established guidelines for minimal standards of care for patients with diabetes who are at risk for amputation. Because each of the 6 components of care assesses different aspects of Medical Care, each was considered to be equally important as part of routine care in this patient population. Thus, each component was equally weighted when assessing Medical Care.
The primary care physician at the very least needs to administer medical care that meets the standards for patients with diabetes. Delivery of care less than that deemed standard for this patient population will undoubtedly lead to undesirable outcomes and increased demand on and cost to the medical system. It was a very disturbing revelation to note that the majority of these patients that had undergone major lower-extremity limb amputations had received medical care that was considered poor. There are no previous reports in the literature that have documented medical care of patients with diabetes that had succumbed to lower-extremity amputations in the manner presented here. In this context, this study offers something new to the literature that may assist others in identifying means of improving medical care and patient compliance in their patients.
In the Consensus Statement from the American Medical Association, the Joint Commission on Accreditation of Healthcare Organizations, and the National Committee for Quality Assurance, data suggest that gaps remain between the care that patients should receive and that which is actually delivered. The evidence provided by this study supports this. There is a recommendation via a national call to physicians and medical centers to establish better documentation of the quality of care being delivered in the US. It is proposed that performance measurements will in turn facilitate improvements in healthcare delivery. Perhaps the use of quality-assurance checks via chart reviews would allow some kind of qualitative and quantitative procedures to assess the degree to which medical care meets the standards of care. At this time, the authors are unaware of any such established policies mandating such quality control. As such, the authors would suggest to all healthcare providers involved in the treatment of patients with diabetes to develop, at the very least, their own performance measures to evaluate medical care and even patient compliance. Based on this study, these factors are intricately involved in advancement to amputation in patients with diabetes. Recognition by medical professionals of their own and their patients’ weaknesses in the management of diabetes will impact the rate of amputation in patients with diabetes.