Thermoregulatory sudomotor dysfunction and diabetic neuropathy develop in parallel in at-risk feet

Aims To establish the longitudinal relationship of foot complications to neuropathy based on a 4-year follow-up of diabetic patients stratified by sudomotor dysfunctions. Methods One hundred and nineteen Type 2 diabetic patients and 36 non-diabetic subjects were initially registered in the prospective cohort study. Plantar skin temperature and sympathetic skin response (SSR) were used to monitor sympathetic mediated thermoregulation and sudomotor function. Peripheral somatic and central autonomic functions were studied using clinical, nerve conduction and cardiovascular reflex tests. At enrolment, the diabetic patients were classified into one of three groups by the progressive stages of sudomotor dysfunction: SSR+ (SSR present; 49 patients), SSR− (SSR absent; 41 patients) and at-risk group (SSR absent but with cracked skin involving partial thickness of the dermis; 29 patients). Results The at-risk group had 13.4 times (95% confidence interval 1.4–125.7) higher plantar ulceration rates than the other two patient groups during the 4 years. Skin temperature elevation occurred in parallel with development of foot sweating problems. There were no significant differences between the three patient groups in the ratios of abnormal heart rate variation, orthostatic test and clinical neuropathy score at follow-up. After 4 years of follow-up, nerve conduction abnormalities were more frequent in the at-risk and SSR− groups than in the SSR+ group. Conclusions Early deterioration of small sympathetic fibres could not be quantified accurately by the clinical, somatic and autonomic tests. Assessing skin integrity and sudomotor function in at-risk individuals identifies early peripheral sympathetic neuropathy, even if the patients have no overt clinical symptoms.     

Clinical profile of diabetic foot infections in south India--a retrospective study.

AIMS: The aim of the study was to determine the profile of diabetes foot infections in south Indian diabetic subjects. The causative factors for delayed wound healing and the recurrence of infection were also studied. METHODS: During a period of 6 months, 374 patients who had undergone some surgical procedure for foot infection were available for follow-up (M:F 227:147, mean age 54.9 +/- 9.4 years, diabetes duration 10.9 +/- 7.7 years). All of them had records of clinical and treatment details, laboratory data including biothesiometry, Doppler tests and electrocardiogram (ECG) records. Foot ulcers were classified according to Wagner's classification. RESULTS: Majority of the patients had grade II and III ulcers (50% and 26.5%, respectively), grade IV was seen in another 21.9%. The median healing time was 44 days. Recurrence of infection which occurred in 53% was more common in patients with neuropathy and peripheral vascular disease (PVD). CONCLUSIONS: Recurrence of foot infection was common among south Indian Type 2 diabetic subjects and was related to the presence of PVD and neuropathy. There is also a need for improvement in footwear and foot care education.     

Mortality in patients with diabetic neuropathic osteoarthropathy (Charcot foot).

OBJECTIVE: To determine the mortality of a population of patients diagnosed with Charcot neuropathic osteoarthropathy managed by a single specialist unit and to compare the results with a control population. METHODS: We have undertaken a retrospective analysis of all cases of Charcot foot on the comprehensive database which has been maintained at the specialist diabetic foot clinic at the City Hospital, Nottingham since 1982. Survival and the incidence of amputation (major and minor) was compared with a control population referred with uncomplicated neuropathic ulceration. Controls were individually matched for gender, age (+/-2 years), disease type, disease duration (+/-2 years) and year of referral (+/-3 years). RESULTS: Forty-seven cases (21 female, 26 male) of Charcot foot were identified, of whom 18 (38.3%) had Type 1 diabetes. Mean age and disease duration at presentation were 59.2 +/- 13.4 (sd) and 16.2 +/- 11.2 years, compared with 59.7 +/- 12.6 and 16.3 +/- 11.2 years, respectively, in the controls. Twenty-one (44.7%) of those with Charcot had died, after a mean interval of 3.7 +/- 2.8 years. This compared with 16 (34.0%) after a mean 3.1 +/- 2.7 years in the control group. Mean duration of follow-up in the survivors was 4.7 +/- 4.9 years (Charcot) and 5.3 +/- 3.9 years (controls). A total of 11 (23.4%) Charcot patients had had a major amputation on the side of the index lesion, compared with five (10.6%) controls. There was no difference between the two groups (P > 0.05, Chi-square). CONCLUSIONS: The mortality in this group of patients with Charcot foot was higher than expected. Nevertheless, there was no difference between those with Charcot and those with uncomplicated neuropathic ulceration. It is possible that it is neuropathy, rather than Charcot osteoarthropathy, which is independently associated with increased mortality in diabetes. The mechanism underlying any such association is not known. There is a need for a formal, prospective, multicentre study to investigate the life expectancy and cardiovascular risk of those with Charcot osteoarthropathy.     

Becaplermin gel in the treatment of diabetic neuropathic foot ulcers

Diabetic foot ulcers remain a major cause of morbidity. Significant progress has been accomplished in ulcer healing by improved management of both ischemia and neuropathy in the diabetic foot. Nevertheless, there is a vital need for further improvement. Becaplermin gel represents an important therapeutic advance for diabetic neuropathic foot ulcers with adequate blood supply. Randomized controlled trials have shown that it is effective in increasing healing rates. However, this efficacy has not translated to positive clinical experience, and the drug is not widely used. Moreover, becaplermin is an expensive medication. Even though it has repeatedly been estimated as cost-effective, its high cost may be prohibitive for some clinicians, especially in developing countries. Clearly, further work is needed to clarify whether use of becaplermin is justified in everyday clinical practice. Future research also needs to assess the potential room for improvement with becaplermin, for instance by combination with other growth factors or by exploring alternative modes of drug delivery.     

Clinical examination for the detection of protective sensation in the feet of diabetic patients

OBJECTIVE: We compared the reproducibility and accuracy of conventional clinical examination of the diabetic foot to monofilament examination. We also sought to simplify the monofilament examination by reducing it to fewer touch points. METHODS: In a cross-sectional study at 10 centers in the United States, Canada, and Switzerland, general internists and residents performed a structured history and physical examination for neuropathy on the feet of diabetic patients. Independent examination by two observers included monofilament sensation, pinprick, vibration, position sense, and ankle reflexes. MAIN RESULTS: A total of 304 patients were examined by at least one practitioner, and 200 received duplicate examinations. Monofilament examination and ankle reflexes had the best reproducibility, with moderate agreement (kappa = 0.59); pinprick, position, and vibration sense had fair agreement (kappa = 0.28-0.36). No component of the history or physical examination, singly or in aggregate, was both sensitive and specific for identifying a patient with an abnormal monofilament examination. A simplified monofilament examination using only 4 sites per foot (total 8 sites) detected 90% of patients with an abnormal 16-site monofilament evaluation. CONCLUSIONS: Conventional clinical examination had low reproducibility and correlated poorly with monofilament examination for the identification of the at-risk patient. The Semmes-Weinstein monofilament examination, a reproducible, valid, and generalizable test of foot sensation, is recommended as the screening procedure of choice for examining diabetic feet.     

Direct measurement of capillary blood flow in the diabetic neuropathic foot

Summary The two major components of the microcirculation in the diabetic neuropathic foot have been examined in detail. Nutritive capillary blood flow was measured directly using the non-invasive technique of television microscopy, applied to the toe nailfold. Arteriovenous shunt flow was assessed using the technique of laser Doppler flowmetry, applied to the toe pulp. Fourteen diabetic patients with peripheral and autonomic neuropathy, 11 with no clinical evidence of neuropathy and 14 normal subjects were studied. Laser Doppler flowmetry (predominantly arteriovenous shunt flow) was increased more than three-fold (p<0.01) in the diabetic patients with neuropathy compared to control subjects, (median 3.57, interquartile range 2.00–5.32 volts vs median 0.93, interquartile range 0.47–2.36 volts respectively). There was no evidence of skin capillary closure. The calculated capillary blood flow (erythrocyte flux) was significantly increased in the diabetic neuropathic patients compared to control subjects (median 76.4, interquartile range 34.4–109.8 picolitres/s vs median 23.2, range 8.0–44.8 picolitres/s, p<0.01). This study demonstrates that foot skin capillary blood flow is increased in diabetic patients with neuropathy. There is, therefore, no evidence to support the supposition that capillary ischaemia, either secondary to a capillary steal phenomenon or advanced microangiopathy, is a feature of diabetic neuropathy under resting conditions.     

New and experimental approaches to treatment of diabetic foot ulcers: a comprehensive review of emerging treatment strategies.

Diabetic foot ulcers occur in up to 15% of all diabetic patients and are a leading cause of nontraumatic amputation worldwide. Neuropathy, abnormal foot biomechanics, peripheral vascular disease and external trauma are the major contributors to the development of a foot ulcer in the diabetic patient. Therapy today includes repeated debridement, offloading, and dressings, for lower grade ulcers, and broad spectrum antibiotics and occasionally limited or complete amputation for higher grades, requiring a team effort of health care workers from various specialties. The large population affected by diabetic foot ulcers and the high rates of failure ending with amputation even with the best therapeutic regimens, have resulted in the development of new therapies and are the focus of this review. These include new off loading techniques, dressings from various materials, methods to promote wound closure using artificial skin grafts, different growth factors or wound bed modulators and methods of debridement. These new techniques are promising but still mostly unproven and traditional approaches cannot be replaced. New and generally more expensive therapies should be seen as adding to traditional approaches.     

Conservative surgical approach versus non-surgical management for diabetic neuropathic foot ulcers: a randomized trial

To test the efficacy of surgical treatment of non-infected neuropathic foot ulcers compared to conventional non-surgical management, a group of diabetic outpatients attending our diabetic foot clinic were studied. All patients who came to the clinic for the first time from January to December 1995 inclusive with an uncomplicated neuropathic ulcer were randomized into two groups. Group A received conservative treatment, consisting of relief of weight-bearing, regular dressings; group B underwent surgical excision, eventual debridement or removal of bone segments underlying the lesion and surgical closure. Healing rate, healing time, prevalence of infection, relapse during a 6-month period following intervention and subjective discomfort were assessed. Twenty-four ulcers in 21 patients were treated in group A (17 Type 2 DM/3 Type 1 DM, age 63.24 ± 13.46 yr, duration of diabetes 18.2 ± 8.41 yr, HbA_1c 9.5 ± 3.8%) and 22 ulcers in 21 patients in group B (19 Type 2 DM/2 Type 1 DM, age 65.53 ± 9.87 yr, duration of diabetes 16.84 ± 10.61 yr; HbA_1c 8.9 ± 2.2%). Healing rate was lower (79.2% = 19/24 ulcers) in group A than in group B (95.5% = 21/22 ulcers; p < 0.05), and healing time was longer (128.9 ± 86.60 days vs 46.73 ± 38.94 days; p < 0.001). Infective complications occurred significantly more often in group A patients (3/24, 12.5% vs 1/22, 4.5%; p < 0.05), as did relapses of ulcerations (8 vs 3; p < 0.01). There were only two minor perioperative complications in group B patients. Patients reported a higher degree of satisfaction in group B (p < 0.01) as well as lower discomfort (p < 0.05) and restrictions (p < 0.05). Thus surgical treatment of neuropathic foot ulcers in diabetic patients proved to be an effective approach compared to conventional treatment in terms of healing time, complications, and relapses, and can be safely performed in an outpatient setting. © 1998 John Wiley & Sons, Ltd.     

Why do foot ulcers recur in diabetic patients?

AIM: To investigate factors predisposing to recurrent foot ulceration in patients with diabetes mellitus. METHODS: Two groups of patients who had attended a specialist Diabetes Foot Centre were assessed: relapsers (n = 26), whose foot ulceration had recurred at least twice, and nonrelapsers (n = 25), whose initial ulcer had not recurred for at least 2 years. RESULTS: In the relapser group 10/26 patients waited at least 24 h before reporting symptoms compared with only 2/25 in the nonrelapser group (P < 0.05). Vibration perception threshold (volts) was 38 +/- 12 (mean +/- SD) in relapsers compared with 25 +/- 13 in nonrelapsers (P < 0.005). Cold perception threshold (degrees C) was 9.1 +/- 4.6 in relapsers compared with 5.1 +/- 3.5 in nonrelapsers (P<0.005). HbA1c (%) was significantly raised at 8.5 +/- 1.7 in relapsers compared with 7.6 +/- 1.2 in nonrelapsers (P = 0.03). Alcohol intake was 0.5 (median, interquartile range 0-2) units per day in relapsers compared with 0.0 (median, interquartile range 0-0.25) units in nonrelapsers (P = 0.04). Smoking habits, housing conditions, visual acuity, threshold for warm perception and the Doppler pressure index were not significantly different in the two groups. CONCLUSIONS: Patients who develop recurrent foot ulceration delay in reporting symptoms, when compared with diabetic patients whose foot ulceration does not recur. The relapsers also have evidence of poorer glycaemic control, more neuropathy and increased alcohol intake.     

The effects of applied felted foam on wound healing and healing times in the therapy of neuropathic diabetic foot ulcers.

AIMS: The application of felted foam is a promising method for plantar pressure reduction in the ulcer region of diabetic foot ulcers, but knowledge of its effects on wound healing is sparse. The objective of this study was to evaluate the effects of felted foam on wound healing in diabetic foot ulcers compared with a standard method of plantar pressure relief. MATERIALS AND METHODS: A total of 54 Type 1 or Type 2 diabetic patients with neuropathic diabetic foot ulcers were evaluated in this prospective randomized controlled study. Ulcer healing was assessed by planimetric measurement of the wound area at beginning of the study and after 10 weeks and at least until wound healing. The patients were consecutively enrolled in the study; 24 patients were randomized to the felted foam therapy, and 30 patients were randomized to conventional therapy. RESULTS: In the felted foam group, the initial average wound area was 102.3 +/- 45.3 mm2 (mean +/- sd), and 5.4 +/- 3.1 mm2 after 10 weeks with an average healing time of 75 days [95% confidence interval (CI) 67-84]. In the conventional therapy group, the initial average wound area was 112.5 +/- 50.8 mm2, and 10.6 +/- 4.2 mm2 after 10 weeks with an average healing time of 85 days (95% CI 79-92) (P = 0.03). The mean wound radius decreased by 0.48 mm (95% CI 0.42-0.56) per week in the felted foam group and by 0.39 mm (95% CI 0.35-0.42) per week in the conventional group (P = 0.005). CONCLUSIONS: The felted foam technique appears to be at least as effective as conventional plantar ulcer treatment. It may be a useful alternative in treating neuropathic foot ulceration, especially in patients who are not able to avoid weight-bearing reliably.     

Prevalence and risk factors for diabetic peripheral neuropathy,neuropathic pain and foot ulceration in the Arabian Gulf region

Aims/IntroductionThis study determined the prevalence and risk factors for diabetic peripheral neuropathy (DPN), painful DPN and diabetic foot ulceration (DFU) in patients with type 2 diabetes in secondary healthcare in Qatar, Kuwait and the Kingdom of Saudi Arabia.Materials and MethodsAdults aged 18–85 years with type 2 diabetes were randomly enrolled from secondary healthcare, and underwent clinical and metabolic assessment. DPN was evaluated using vibration perception threshold and neuropathic symptoms and painful Diabetic Peripheral Neuropathy was evaluated using the Douleur Neuropathique 4 questionnaire.ResultsA total of 3,021 individuals were recruited between June 2017 and May 2019. The prevalence of DPN was 33.3%, of whom 52.2% were at risk of DFU and 53.6% were undiagnosed. The prevalence of painful DPN was 43.3%, of whom 54.3% were undiagnosed. DFU was present in 2.9%. The adjusted odds ratios for DPN and painful DPN were higher with increasing diabetes duration, obesity, poor glycemic control and hyperlipidemia, and lower with greater physical activity. The adjusted odds ratio for DFU was higher with the presence of DPN, severe loss of vibration perception, hypertension and vitamin D deficiency.ConclusionsThis is the largest study to date from the Middle East showing a high prevalence of undiagnosed DPN, painful DPN and those at risk of DFU in patients with type 2 diabetes, and identifies their respective risk factors.     

The role of nitric oxide synthase isoforms and arginase in the pathogenesis of diabetic foot ulcers: possible modulatory effects by transforming growth factor beta 1

Aims/hypothesis. l-arginine, an amino acid involved in wound healing, is metabolised by one of two pathways; nitric oxide synthase and arginase. If metabolised by nitric oxide synthase, this can result in tissue destruction, or matrix deposition if metabolised by arginase. The aim therefore was to investigate the role of these enzymes in the pathogenesis of diabetic foot ulcers. Methods. The activity, proteins by Western blot analysis and cellular distribution (using immunocytochemistry) of these enzymes were measured in diabetic foot ulcers, diabetic skin and normal skin. Results. Total and inducible nitric oxide synthase (p < 0.001) and endothelial nitric oxide synthase were increased in diabetic ulcers compared with diabetic and normal skin and were associated with increased plasma nitrite concentrations in diabetic ulcers (p < 0.05). Inducible nitric oxide synthase was the major isoform, with the macrophage being the predominant cellular source. Similarly arginase activity was increased (p < 0.01) in diabetic ulcers. The protein levels corroborated with the activity data, with the fibroblast being the major cellular source. The spatial and cellular distribution of the two enzyme systems was distinct. Transforming growth factor-beta1 was decreased in diabetic ulcers in comparison with diabetic skin and normal skin. Conclusion/interpretation. Increased nitric oxide synthase activity in diabetic foot ulcers may be responsible for the impaired healing in this disease. Furthermore, the increased activity of arginase could account for the characteristic callus formation around these ulcers. In addition, the lower concentrations of transforming growth factor-beta1 in diabetic ulcers may explain the raised concentrations of nitric oxide in this condition. [Diabetologia (1999) 42: 748–757] Received: 23 September 1998 and in revised form: 10 December 1998     

Sudomotor dysfunction is associated with foot ulceration in diabetes

Aim To examine the relationship between sudomotor dysfunction and foot ulceration (FU) in patients with diabetes. Methods Ninety patients with either Type 1 or Type 2 diabetes [30 without peripheral sensorimotor neuropathy (PN), 30 with PN but without FU and 30 with FU] were recruited in this cross‐sectional study. Assessment of PN was based on neuropathy symptom score (NSS), neuropathy disability score (NDS) and vibration perception threshold (VPT). Sudomotor dysfunction was assessed using the sympathetic skin response (SSR). Cardiac autonomic nervous system activity was assessed by the battery of the classical autonomic function tests. Results Patients with foot ulcers had longer duration of diabetes, higher values of VPT and NDS and lower values of the autonomic functions tests in comparison with the other study groups. Sudomotor dysfunction and cardiac autonomic neuropathy were significantly more common in the FU group. Multivariate logistic regression analysis after adjustment for gender, body mass index, duration of diabetes and glycated haemoglobin (HbA_1c) demonstrated that the odds ratio (95% confidence intervals) of FU increased with measures of neuropathy such as NDS ≥ 6 (10.2, 6.2–17.3) and VPT ≥ 25 volts (19.8, 9.9–47.5), but was also significantly increased with absent SSR (15.3, 5.3–38.4). Conclusions Sudomotor dysfunction is associated with increased risk of FU and should be included in the screening tests for identification of diabetic patients at risk of ulceration.     

Implementation of diabetic foot ulcer classification system for research purposes to predict lower extremity amputation

BACKROUND:

Patients with diabetic foot ulcers are at a high risk of having both minor or major lower extremity amputations.

AIM:

To identify the extent of risk factors for major and minor amputations in patients with diabetic foot ulcers.

MATERIALS AND METHODS:

This prospective study was conducted from 2003 to 2005. Using the guidelines for wound classification developed by the International Consensus of the Diabetic Foot, patients were assessed for ischemia, neuropathy, linear measurement of wound diameters, depth of wound, and infection. In addition, end stage renal failure was added as a criterion to assess the association of all these criteria with both toe and lower extremity amputation.

RESULTS:

2,321 patients were studied and their mean age was 55 ± 12 years. Most (83.5%) of the patients presented with foot ulcers (n = 1394). Plantar ulcers were the most common (42.6%) followed by ulcers of the big toe (39%). Some (28.5%) of the patients had different types of amputations: 10% had major lower extreme amputation (MLEA) with 8.7% amputations being below the knee and minor (toe) amputations accounting for 18.5%. The most commonly amputated (9.9%) toe was the first toe.

CONCLUSION:

The guidelines for wound classification proposed by the International Consensus of the Diabetic Foot are reliable predictive factors and can determine the outcome of diabetic foot management. Significant factors associated with MLEA were ischemia, neuropathy, and end-stage renal disease and those associated with toe amputation were neuropathy, depth of wound, and grade of infection.     

Elevation of von Willebrand factor in plasma in diabetic patients with neuropathic foot ulceration.

AIMS: The present study examines the relationship between markers of endothelial dysfunction and diabetic neuropathy or consequent neuropathic foot ulceration in patients with Type 2 diabetes mellitus. METHODS: We studied 65 Type 2 diabetic patients including 25 diabetic patients without neuropathy, 27 with neuropathy but no history of foot ulceration, and 13 with neuropathic ulceration. Plasma concentrations of von Willebrand factor (vWF) and soluble thrombomodulin (TM), measures of endothelial dysfunction, were determined by enzyme immunoassays. We performed various tests quantifying aspects of diabetic neuropathy including vibration perception threshold (VPT; for sensory neuropathy), coefficient of variation of R-R intervals (CVR-R; for cardiac autonomic neuropathy), and cold-induced vasodilation in the great toe for peripheral sympathetic neuropathy. RESULTS: CVR-R and cold-induced vasodilation were significantly diminished in patients with neuropathic foot ulceration compared with patients with neuropathy but no history of foot ulceration. Plasma vWF concentrations were positively correlated with VPT and cold-induced vasodilation test, and were inversely correlated with CVR-R. Multivariate analysis disclosed that VPT and percentage vasodilation were independent factors for plasma vWF. Plasma vWF was significantly elevated in patients with foot ulceration compared with patients without neuropathy or those with neuropathy but not foot ulceration. However, plasma TM concentrations did not differ between the three groups. CONCLUSIONS: Diabetic patients with neuropathic foot ulceration had severe impairment of cardiac autonomic and peripheral sympathetic nerves. Elevation of vWF in plasma was associated with neuropathic foot ulceration, linking endothelial dysfunction to foot ulceration.     

The risk of foot ulceration in diabetic patients with high foot pressure: a prospective study

Summary Foot ulceration results in substantial morbidity amongst diabetic patients. We have studied prospectively the relationship between high foot pressures and foot ulceration using an optical pedobarograph. A series of 86 diabetic patients, mean age 53.3 (range 17–77) years, mean duration of diabetes 17.1 (range 1–36) years, were followed-up for a mean period of 30 (range 15–34) months. Clinical neuropathy was present in 58 (67%) patients at baseline examination. Mean peak foot pressure was higher at the follow-up compared to baseline (13.5 kg·cm^–2±7.1 SD vs 11.2±5.4, p<0.001) with abnormally high foot pressures (>12.3) being present in 55 patients at follow-up and 43 at the baseline visit (p=NS). Plantar foot ulcers developed in 21 feet of 15 patients (17%), all of whom had abnormally high pressures at baseline; neuropathy was present in 14 patients at baseline. Non-plantar ulcers occurred in 8 (9%) patients. Thus, plantar ulceration occurred in 35% of diabetic patients with high foot pressures but in none of those with normal pressures. We have shown for the first time in a prospective study that high plantar foot pressures in diabetic patients are strongly predictive of subsequent plantar ulceration, especially in the presence of neuropathy.     

强化教育干预对糖尿病足预防的中远期效果

目的观察强化足部护理教育干预对糖尿病（DM）是预防的中远期效果，探讨由DM教育护士实施的DM足的预防护理教育干预的可行性和有效性。方法采用实验性研究方法，教育干预组86例（入组110例，失访24例）、对照组92例（入组110例，失访18例）。对照组实施常规DM治疗和DM基本知识教育，实验前和实验后9个月时收集相关资料。教育干预组除接受与对照组相同的措施外，给予个体化DM足预防护理知识与行为干预，首次干预后1，3，6，9个月时分别复诊继续接受强化教育指导，以调查评价研究表评价足部教育干预对DM足预防的作用。结果DM足预防护理教育干预9个月后，教育干预组患者对DM足的认识、早期筛查知识、日常足部护理、合适鞋袜选择、修剪趾甲等知识评分显著提高，日常足部护理行为均明显改善（P〈0．05-P〈0．01）。教育干预组患者足部皮肤病理性损害明显减少，足部胼胝发生率、足部皮肤损伤率、足癣发生率、皮肤干燥、皲裂发生率明显低于对照组（P〈0．05-P〈0．001）。血糖（空腹血糖、餐后2h血糖）、HbAlc、血压等代谢指标较对照组明显改善（P〈0．05）。结论由DM教育护士实施的DM足的预防护理教育干预是可行、有效的。研究结果显示了DM足的预防护理教育干预在减少DM足发生中的重要作用，以及个体化足病预防护理教育干预对DM足预防的中远期效果。