Mönckeberg's sclerosis after sympathetic denervation in diabetic and non-diabetic subjects

Periosteal distraction as a new surgical technique for the treatment of senile diabetic foot: A retrospective case analysis

This study investigates the clinical effect and safety of periosteal distraction in the treatment of senile diabetic foot. The clinical data of 45 patients with diabetic foot treated with periosteal distraction in the Central Hospital of Dalian University of Technology from January 2020 to May 2024 were retrospectively analyzed. Finally, 42 patients were followed up, and 3 patients were lost to follow-up, including 29 males and 13 females, aged (71.17 ± 6.43), (62-84) years respectively. The Wagner grade of the ulcer surface of the affected foot was grade 2 in 25 cases, grade 3 in 13 cases, and grade 4 in 4 cases; the ulcer sites were toes in 18 cases, soles in 14 cases, dorsum of the foot in 8 cases, heels in 1 case, and ankles in 1 case. The toe oxygen saturation, ankle-brachial index (ABI), skin temperature and visual analogue score (VAS) were recorded before operation and at 1 day, 7 days, 14 days, 1 month, 2 months, and 3 months after operation. The therapeutic effect was observed and evaluated in combination with Michigan neurological sign score and lower limb computed tomography angiography. The wound ulcer healing rate, amputation rate and ulcer recurrence were also counted. The toe oxygen saturation, ABI, skin temperature, VAS score and Michigan neurological sign score of all patients were significantly improved after operation compared with those before operation, and the differences were statistically significant (P < .05); After a 3-month post-surgery period, 37 patients were observed to have microcirculation formation in the affected limb, as well as increased and thickened lower extremity arterioles in comparison to pre-surgery conditions, forming an interwoven network. During the follow-up period, 21 patients exhibited healed foot ulcers at 2 months post-surgery, while by the end of the follow-up period, 38 patients had healed foot ulcers, 5 patients had experienced a significant reduction in wound ulcer area, and the overall ulcer healing rate was 90%. Notably, no instances of amputation or ulcer recurrence were observed during treatment. Periosteal distraction is a new surgical method for the treatment of senile diabetic foot ulcer, which can obtain satisfactory short-term efficacy and is worthy of clinical promotion.

Medial arterial calcification of the lower limbs in diabetes: Time for awareness? A short narrative review

In patients with diabetes, peripheral arterial disease, particularly below the knee, is associated with medial arterial calcification. This is a frequent and potentially serious complication, affecting all types of diabetes. In recent years, our understanding of the pathophysiology and clinical significance of medial arterial calcification has improved considerably. Here, we offer a short narrative review of the epidemiology, clinical consequences, and pathophysiology of this complication. Now that medial arterial calcification of the lower limbs is better understood, we also focus on the prospect of treatments targeting arterial calcification.

[Arterial mediacalcinosis in patients with diabetes mellitus: etiopathogenetic and histopathological aspects]

In a review of the generalized results of foreign and domestic studies on the development mechanism and pathogenesis of vascular calcification. The etiopathogenetic, pathophysiological and histomorphological features of mediacalcinosis, which reveal changes in the vascular bed in patients with DM, are considered. The role of risk factors for diseases, such as increased glycemia, changes in insulin levels, impaired lipid metabolism, obesity, arterial hypertension, CKD and aging, is indicated. The role of procalcifying and anticalcifying factors in colonic vascular remodeling is discussed. Identification of informative molecular markers and factors of CS will allow in the future to develop effective strategies for drug management of the risk of their progression and individual prevention programs to improve the quality and life expectancy in patients with cardiovascular diseases.

Detecting and treating the protean manifestations of diabetic autonomic neuropathy

The manifestations of diabetic autonomic neuropathy (DAN) are protean and clinically involve multiple systems, including the cardiovascular system, the gastrointestinal system, the genitourinary system as well as the sweat glands (sudomotor dysfunction) and the gallbladder. In addition, cardiac autonomic neuropathy (CAN) is associated with a correctible inability to appreciate and correct hypoglycaemia. While not a clinical problem, pupillary involvement should be the clue and the catalyst to investigate for other manifestations of DAN. This review outlines a practical approach to detecting and investigating the manifestations of DAN. Of particular importance is early detection of cardiovascular involvement where prompt therapy through glycaemic control can decrease the severity of CAN and decelerate the frequency and severity of retinopathy and nephropathy in addition to decreasing cardiovascular events and mortality. CAN also plays a role in accelerating other diabetic complications such as acute ischaemic stroke, heart failure, medial artery calcinosis, foot ulcers, peripheral artery disease and Charcot joints. Many therapies of DAN are available, which should not only decrease morbidity and mortality from DAN, but also improve the patient's quality of life. However, the therapies available are largely symptomatic.

The Charcot Foot Reflects a Response to Injury That Is Critically Distorted by Preexisting Nerve Damage: An Imperfect Storm

It has been recognized since comprehensive descriptions by Jean-Martin Charcot in 1868 and 1883 that development of what is usually known as neuropathic osteoarthropathy (or the Charcot foot) requires the coincidence of neuropathy and inflammation. Despite this, detailed understanding of the causes has remained remarkably limited in the succeeding century and a half. The aim of this descriptive account is to draw particular attention to the processes involved in both the onset and resolution of the inflammation that is an essential component of active disease. The principal observation is that while neuropathy is common in people with diabetes, the inflammation and secondary skeletal damage that characterize neuropathic osteoarthropathy are observed in only a small minority of people with diabetes and with neuropathy. We therefore argue that the key to understanding the causes of the Charcot foot is to focus equally on those who have active disease as well as those who do not. Although neuropathy is essential for development of the disorder, neuropathy also has an adverse impact on the mechanisms involved in the onset of inflammation, and these may be critically affected in the majority of those who are susceptible. The Charcot foot is uncommon in people with diabetes (or any other cause of neuropathy) because the large majority of those with neuropathy may have also lost the capacity to mount the specific inflammatory reaction that is essential for its development.

Monckeberg's Medial Sclerosis as a Cause for Headache and Facial Pain

PURPOSE OF REVIEW

Mönckeberg's medial sclerosis (MMS) is a chronic, non-inflammatory degenerative condition affecting primarily the tunica media of muscular arteries resulting in their calcification. The purpose of this comprehensive review is to describe MMS as it appears in the literature, in the context of headache and facial pain. Understanding the etiopathology, the associated conditions, and the differential diagnoses is important in managing MMS.

RECENT FINDINGS

Management of MMS primarily depends upon identification of its associated conditions and their treatment. Due to the rare incidence and inadequate literature on MMS presenting with headaches, the diagnosis of the pain and the entity itself is challenging. MMS is characterized by associated systemic conditions and absence of inflammatory markers. It can mimic giant cell arteritis (GCA) and other pain entities. An interdisciplinary approach involving appropriate specialties is recommended.

From organic and inorganic phosphates to valvular and vascular calcifications

Calcification of the arterial wall and valves is an important part of the pathophysiological process of peripheral and coronary atherosclerosis, aortic stenosis, ageing, diabetes, and chronic kidney disease. This review aims to better understand how extracellular phosphates and their ability to be retained as calcium phosphates on the extracellular matrix initiate the mineralization process of arteries and valves. In this context, the physiological process of bone mineralization remains a human model for pathological soft tissue mineralization. Soluble (ionized) calcium precipitation occurs on extracellular phosphates; either with inorganic or on exposed organic phosphates. Organic phosphates are classified as either structural (phospholipids, nucleic acids) or energetic (corresponding to phosphoryl transfer activities). Extracellular phosphates promote a phenotypic shift in vascular smooth muscle and valvular interstitial cells towards an osteoblast gene expression pattern, which provokes the active phase of mineralization. A line of defense systems protects arterial and valvular tissue calcifications. Given the major roles of phosphate in soft tissue calcification, phosphate mimetics, and/or prevention of phosphate dissipation represent novel potential therapeutic approaches for arterial and valvular calcification.

Factors associated with sclerostin levels - A calcification inhibitor - In individuals with type 2 diabetes mellitus; Is autonomic neuropathy the missing link?

BACKGROUND

Sclerostin inhibits bone formation and its expression is upregulated in the vasculature during the arterial calcification process as a counterregulatory mechanism preventing further calcification. Lower extremity arterial calcification (LEAC) is common in neuropathic patients with type 2 diabetes (T2DM). Herein, we investigated for associations between plasma sclerostin levels and diabetic neuropathy as well as LEAC in subjects with T2DM.

METHODS

A total of 74 individuals with and 76 without T2DMwere recruited. Plasma sclerostin levels were measured by ELISA. Diagnosis of cardiac autonomic neuropathy (CAN) was based on the battery of the four autonomic tests, while of somatosensory peripheral neuropathy (DPN) on neuropathy symptom score and neuropathy disability score. LEAC was assessed with conventional ankle and foot x-rays.

RESULTS

Plasma sclerostin levels were higher in participants with LEAC vs. those without LEAC in both diabetes and non-diabetes cohorts (p = 0.035 and p = 0.003, respectively). In the diabetes cohort, patients with CAN, but not with DPN, had higher sclerostin levels when compared with those without CAN (p < 0.001). Multivariate analysis in the diabetes cohort demonstrated that sclerostin levels were associated positively with CAN and LEAC, while in the non-diabetes cohort there was a trend for a positive association with male gender and presence of LEAC.

CONCLUSION

Plasma sclerostin levels are increased in individuals with LEAC irrespectively of diabetes status. In addition, plasma sclerostin concentrations are associated independently with LEAC and CAN in people with T2DM.

Bilateral Lower Limb Disabling Claudication in a Young Man: A Case of Mönckeberg’s Arteriosclerosis

Mönckeberg’s arteriosclerosis, also called medial calcific sclerosis or Mönckeberg’s sclerosis, is a form of vessel hardening due to increased calcium deposits in the tunica media layer. There is disagreement over its clinical significance and aetiology and its relation to atherosclerosis and vascular calcification. Its clinical presentations and treatment are still debated. More effort should be directed on attempting to distinguish between atherosclerotic lesions and Mönckeberg’s lesions on the basis of age, location and the pattern of calcifications where there is considerable overlap between intimal or medial and involvement of the internal elastic lamina border between those planes. In-depth research is still needed to create consensus guidelines for the diagnosis and management of this condition. This article includes a review of the literature and a case report of a 22-year-old man with the condition.

Vascular disease in the lower limb in type 1 diabetes

This review considers peripheral arterial disease (PAD) in the diabetic ischaemic lower limb including both macrovascular and microvascular aspects. The presentation of PAD is probably not significantly different in type 1 compared with type 2 diabetes. PAD in diabetic patients is diffuse and located distally being most severe in the crural and also the foot arteries. It is associated with arterial calcification and occlusion of the arteries rather than stenosis. Compared with the nondiabetic patient, PAD develops at a younger age, and women are equally affected as men. It is not known whether the presentation of ischaemic lower limb disease in diabetes can be explained by one disease, namely, atherosclerosis, which has particular features peculiar to diabetes such as distal arterial involvement, or by the occurrence of two separate diseases: first, classical atherosclerosis and, second, a diabetic macroangiopathy, a term for nonatherosclerotic arterial disease in diabetes that is characterized by medial arterial calcification. Furthermore, there is controversy with regard to the significance of structural changes in the microcirculation of the diabetic foot.

Comparison of perfusion values after percutaneous transluminal angioplasty according to the severity of ischaemia in the diabetic foot

Percutaneous transluminal angioplasty (PTA) is now more frequently used to improve tissue perfusion in ischemic diabetic feet. However, there are concerns about its feasibility and effectiveness in severely ischaemic feet. This study aimed to compare the perfusion values after PTA according to the ischaemic degree of diabetic feet. This study included 133 ischaemic diabetic feet. The foot transcutaneous oxygen pressure (TcPO₂ ) and toe pressure were measured before the procedure and every second postoperative week for 6 weeks. The patients were divided into three groups according to ischaemic severity on the basis of TcPO₂ and toe pressures. In the "severely ischaemic" group, the TcPO₂ increased from 7.5 ± 4.9 to 40.3 ± 11.3 mm Hg (5.4-fold) 6 weeks after the PTA (P < 0.001). The toe pressure increased from 8.5 ± 8.8 to 42.2 ± 19.3 mm Hg (5.0-fold, P < 0.001). In the "mild" group, the TcPO₂ increased from 35.4 ± 2.5 to 41.8 ± 12.4 mm Hg (1.2-fold, P = 0.003), and the toe pressure increased from 45.7 ± 12.3 to 54.3 ± 31.3 mm Hg (1.2-fold, P > 0.05). Results of the "intermediate" group were in between. The most severely ischaemic group had the most dramatic increase of tissue perfusion after PTA. As such, PTA can be an effective method for increasing tissue perfusion even in the severely ischaemic diabetic feet.

Specimen Identification Errors in Breast Biopsies: Age Matters. Report of Two Near-Miss Events and Review of the Literature

The consequences of patient identification errors due to specimen mislabeling can be deleterious. We describe two near-miss events involving mislabeled breast specimens from two patients who sought treatment at our institution. In both cases, microscopic review of the slides identified inconsistencies between the histologic findings and patient age, unveiling specimen identification errors. By correlating the clinical information with the microscopic findings, we identified mistakes that had occurred at the time of specimen accessioning at the original laboratories. In both cases, thanks to a timely reassignment of the specimens, the patients suffered no harm. These cases highlight the importance of routine clinical and pathologic correlation as a critical component of quality assurance and patient safety. A review of possible specimen identification errors in the anatomic pathology setting is presented.

Arterial Calcification in Diabetes Mellitus: Preclinical Models and Translational Implications

Diabetes mellitus increasingly afflicts our aging and dysmetabolic population. Type 2 diabetes mellitus and the antecedent metabolic syndrome represent the vast majority of the disease burden-increasingly prevalent in children and older adults. However, type 1 diabetes mellitus is also advancing in preadolescent children. As such, a crushing wave of cardiometabolic disease burden now faces our society. Arteriosclerotic calcification is increased in metabolic syndrome, type 2 diabetes mellitus, and type 1 diabetes mellitus-impairing conduit vessel compliance and function, thereby increasing the risk for dementia, stroke, heart attack, limb ischemia, renal insufficiency, and lower extremity amputation. Preclinical models of these dysmetabolic settings have provided insights into the pathobiology of arterial calcification. Osteochondrogenic morphogens in the BMP-Wnt signaling relay and transcriptional regulatory programs driven by Msx and Runx gene families are entrained to innate immune responses-responses activated by the dysmetabolic state-to direct arterial matrix deposition and mineralization. Recent studies implicate the endothelial-mesenchymal transition in contributing to the phenotypic drift of mineralizing vascular progenitors. In this brief overview, we discuss preclinical disease models that provide mechanistic insights-and point to challenges and opportunities to translate these insights into new therapeutic strategies for our patients afflicted with diabetes mellitus and its arteriosclerotic complications.

Assessment of Toe Blood Pressure Is an Effective Screening Method to Identify Diabetes Patients with Lower Extremity Arterial Disease

The authors evaluated a screening program for lower extremity arterial disease (LEAD) in diabetic patients and focused on the value of toe blood pressure assessment. They recruited 437 subjects, ages 30-70 years (134 healthy controls, 166 type 1 and 137 type 2 diabetic patients; control [Ctr], DM1, and DM2) with no previous history of LEAD. They were enrolled in a longitudinal study with a planned follow-up of 10 years. Patients were consecutively enrolled from outpatient diabetes units of 2 university hospitals. Subjects were screened with respect to peripheral circulation by use of established noninvasive techniques. These included arm, ankle (AP), and toe (TP) blood pressure measurements; evaluation of peripheral neuropathy; and a standardized physical examination. Results from the baseline examination are presented in this report. The number of patients who presented peripheral pressures or indices below normal (< mean -2 SD for controls) was higher among diabetic patients; 24% of DM1 and 31% of DM2, as compared to 6% of Ctr, had at least 1 lower limb with a low TP, AP, toe/arm index (TI), or ankle/arm index (AI), and these subjects were mainly identified by using the toe/arm index. TI was independently and negatively associated with fasting blood glucose in both patient groups, and with smoking, age, and diabetes duration in DM1. The mean AP was higher in the DM1 and DM2 groups compared to Ctr, whereas overall TP, TI, and AI were similar in the groups. It was also shown that abnormally low TI was significantly more common than low AI among diabetics (p<0.001), and this was true for TP vs AP as well (p<0.05). It is beneficial to include assessment of toe blood pressure and toe/arm blood pressure index to detect early LEAD in diabetic patients. Ankle blood pressure and indices alone are less efficient, owing probably to medial sclerosis in diabetic patients. Up to 30% of diabetic patients with no ischemic symptoms may have signs of impaired arterial circulation.

Review: The clinical evaluation of lower limb perfusion in diabetic foot disease

Athorough clinical assessment and evaluation of foot perfusion is essential in managing diabetic foot disease. The treatment of macrovascular disease is key to reducing the high amputation rates seen in diabetic patients, particularly as small vessel dysfunction may make diabetic individuals more vulnerable to the effects of macrovascular, atherosclerotic disease. The clinical assessment remains paramount in the management of diabetic foot disease. The confounding effects of peripheral neuropathy on the symptoms and signs of lower limb arterial insufficiency can make assessment difficult. This article provides a resume of the clinical manifestation of lower limb ischaemia and neuropathy and the importance of accurate evaluation of the diabetic foot.

Review: The laboratory evaluation of lower limb perfusion in diabetes mellitus. A clinical review

on-invasive laboratory tests are commonly employed in the assessment of lower limb perfusion. The accuracy of non-invasive assessments in diabetes remains a concern. We evaluated the more commonly used methods with particular reference to diabetic foot disease. A literature review and clinical evaluation of tests for macrovascular disease, including hand held Doppler, blood pressure measurement and indices, Doppler waveform analysis, colour duplex imaging and plethysmography was performed. Tests reflecting tissue perfusion, including infrared detectors, transcutaneous oxygen tension, laser Doppler, capillaroscopy and skin temperature were also reviewed. Non-invasive laboratory tests reduce the requirement for invasive investigations and their inherent risks. More traditional non-invasive methods are being replaced by evolving techniques employing ultrasound technology. Arterial calcification and peripheral neuropathy associated with diabetes can potentially reduce the reliability of these methods. Distal limb and tissue perfusion assessments are more likely to reflect local vascularity. Tissue perfusion indicators are generally slow and vulnerable to environmental influences, thus limiting their clinical use. Nevertheless, non-invasive tests are an important adjunct to the clinical evaluation of diabetic foot disease. However, diabetes potentially reduces their reliability and the results require careful interpretation. Distal perfusion tests have potential advantages over macrovascular assessments. The influence of diabetes on non-invasive tests needs further evaluation.

Medial Arterial Calcification: An Overlooked Player in Peripheral Arterial Disease

Peripheral arterial disease (PAD) is a global health issue that is becoming more prevalent in an aging world population. Diabetes mellitus and chronic kidney disease are also on the increase, and both are associated with accelerated vascular calcification and an unfavorable prognosis in PAD. These data challenge the traditional athero-centric view of PAD, instead pointing toward a disease process complicated by medial arterial calcification. Like atherosclerosis, aging is a potent risk factor for medial arterial calcification, and accelerated vascular aging may underpin the devastating manifestations of PAD, particularly in patients prone to calcification. Consequently, this review will attempt to dissect the relationship between medial arterial calcification and atherosclerosis in PAD and identify common as well as novel risk factors that may contribute to and accelerate progression of PAD. In this context, we focus on the complex interplay between oxidative stress, DNA damage, and vascular aging, as well as the unexplored role of neuropathy.

Noninvasive Arterial Testing in Patients With Diabetes: A Guide for Foot and Ankle Surgeons

BACKGROUND

This study was designed to compare the findings of noninvasive arterial testing in patients with and without diabetic foot pathology.

METHODS

The ABI (ankle brachial index), TBI (toe brachial index), and great toe pressures were measured in 207 patients. PAD (peripheral artery disease) was defined as an ABI < 0.91 on either extremity or a TBI < 0.7.

RESULTS

PAD was identified in 103 of the 207 patients (49.8%), 80 patients with diabetic foot pathology and 23 patients with nondiabetic foot pathology. Although patients with diabetic foot pathology were 1.4 times more likely to have PAD compared to patients without diabetic pathology, this increased risk was not statistically significant (OR 1.41 [95% CI 0.75-2.64], P = .28). Patients with PAD and diabetic foot pathology were 4.9 times more likely to have ischemia (toe pressure < 60 mm Hg) than patients with PAD and nondiabetic foot pathology (OR 4.93 [95% CI 1.35-17.94], P < .05). Patients on dialysis had a 7.3 times increased likelihood of having PAD compared to patients not on dialysis (OR 7.3 [95% CI 1.6-33.6], P < .01). Patients with absent pedal pulses were 4.9 more likely to have PAD than patients with normal pulses (OR 4.9 [95% CI 2.6-9.4], P < .0001). PAD was identified in 97 of 188 patients (51.6%) with peripheral neuropathy compared to 6 of 19 patients (31.5%) without peripheral neuropathy (OR 2.31 [95% CI 0.84-6.33], P = .10).

CONCLUSIONS

Combining the ABI with TBI improved the ability to diagnose PAD in diabetic patients because the ABI has high specificity (low false positives) and the TBI has high sensitivity (low false negatives). The TBI was more reliable in patients with noncompressible arteries, medial artery calcinosis and/or neuropathy. Due to the relative incompressibility of calcified distal arteries in patients with DM, the ABI may be within normal limits in patients with PAD. This false negative result may lead surgeons to assume that normal perfusion is present.

Diagnosis and assessment of peripheral arterial disease in the diabetic foot

Approximately half of all patients with a diabetic foot ulcer have co-existing peripheral arterial disease. Identifying peripheral arterial disease among patients with foot ulceration is important, given its association with failure to heal, amputation, cardiovascular events and increased risk of premature mortality. Infection, oedema and neuropathy, often present with ulceration, may adversely affect the performance of diagnostic tests that are reliable in patients without diabetes. Early recognition and expert assessment of peripheral arterial disease allows measures to be taken to reduce the risk of amputation and cardiovascular events, while determining the need for revascularization to promote ulcer healing. When peripheral arterial disease is diagnosed, the extent of perfusion deficit should be measured. Patients with a severe perfusion deficit, likely to affect ulcer healing, will require further imaging to define the anatomy of disease and indicate whether a revascularization procedure is appropriate.

Arterial calcification: Finger-pointing at resident and circulating stem cells

The term ‘‘Stammzelle’’ (stem cells) originally appeared in 1868 in the works of Ernst Haeckel who used it to describe the ancestor unicellular organism from which he presumed all multicellular organisms evolved. Since then stem cells have been studied in a wide spectrum of normal and pathological conditions; it is remarkable to note that ectopic arterial calcification was considered a passive deposit of calcium since its original discovering in 1877; in the last decades, resident and circulating stem cells were imaged to drive arterial calcification through chondro-osteogenic differentiation thus opening the idea that an active mechanism could be at the basis of the process that clinically shows a Janus effect: calcifications either lead to the stabilization or rupture of the atherosclerotic plaques. A review of the literature underlines that 130 years after stem cell discovery, antigenic markers of stem cells are still debated and the identification of the osteoprogenitor phenotype is even more elusive due to tissue degradation occurring at processing and manipulation. It is necessary to find a consensus to perform comparable studies that implies phenotypic recognition of stem cells antigens. A hypothesis is based on the singular morphology and amitotic mechanism of division of osteoclasts: it constitutes the opening to a new approach on osteoprogenitors markers and recognition. Our aim was to highlight all the present evidences of the active calcification process, summarize the different cellular types involved, and discuss a novel approach to discover osteoprogenitor phenotypes in arterial wall.

Below-knee arterial calcification in type 2 diabetes: association with receptor activator of nuclear factor κB ligand, osteoprotegerin, and neuropathy

CONTEXT

Calcification of the arterial wall in diabetes contributes to the arterial occlusive process occurring below the knee. The osteoprotegerin (OPG)/receptor activator of nuclear factor κB ligand (RANKL) system is suspected to be involved in the calcification process.

OBJECTIVE

The aim of the study was to investigate whether there is a link between arterial calcification in type 2 diabetes and 1) conventional cardiovascular risk factors, 2) serum RANKL and OPG levels, and 3) neuropathy.

PATIENTS AND METHODS

We objectively scored, in a cross-sectional study, infrapopliteal vascular calcification using computed tomography scanning in 198 patients with type 2 diabetes, a high cardiovascular risk, and a glomerular filtration rate >30 mL/min. Color duplex ultrasonography was performed to assess peripheral arterial occlusive disease, and mediacalcosis. Peripheral neuropathy was defined by a neuropathy disability score >6. RANKL and OPG were measured in the serum by routine chemistry.

RESULTS

Below-knee arterial calcification was associated with arterial occlusive disease. In multivariate logistic regression analysis, the variables significantly and independently associated with the calcification score were age (odds ratio [OR] = 1.08; 95% confidence interval [CI] = 1.04-1.13; P < .0001), male gender (OR = 3.53; 95% CI = 1.54-8.08; P = .003), previous cardiovascular disease (OR = 2.78; 95% CI = 1.39-5.59; P = .005), and neuropathy disability score (per 1 point, OR = 1.21; 95% CI = 1.05-1.38; P = .006). The association with ln OPG, significantly associated with calcification score in univariate analysis (OR = 3.14; 95% CI = 1.05-9.40; P = .045), was no longer significant in multivariate analysis. RANKL and OPG/RANKL were not significantly associated with the calcification score.

CONCLUSIONS

Below-knee arterial calcification severity is clearly correlated with peripheral neuropathy severity and with several usual cardiovascular risk factors, but not with serum RANKL level.

Computed tomography of aortic wall calcifications in aortic dissection patients

Objectives

To investigate the frequency of aortic calcifications at the outer edge of the false lumen and the frequency of fully circular aortic calcifications in a consecutive series of patients with aortic dissection who underwent contrast-enhanced CT.

Methods

The study population compromised of 69 consecutive subjects aged 60 years and older with a contrast-enhanced CT scan demonstrating an aortic dissection. All CT scans were evaluated for the frequency of aortic calcifications at the outer edge of the false lumen and the frequency of fully circular aortic calcifications by two experienced observers. Between observer reliability was evaluated by using Cohen’s Kappa. Differences between groups were tested using unpaired T test and Chi-square test.

Results

Presumed media calcifications were observed in 22 (32%) patients of 60 years and older and were found more frequently in chronic aortic dissection (N = 12/23, 52%) than in acute aortic dissection (N = 10/46, 22%).

Conclusion

As the intima has been torn away by the aortic dissection it is highly likely that CT scans can visualize the calcifications in the tunica media of the aorta.

Influence of peripheral vascular calcification on efficiency of screening tests for peripheral arterial occlusive disease in diabetes--a cross-sectional study

AIMS

Pulse palpation and ankle brachial index are recommended to screen for peripheral arterial occlusive disease in people with diabetes. However, vascular calcification can be associated with false negative tests (arteriopathy present despite normal screening tests). We therefore studied the impact of peripheral vascular calcification on the performance of these tests.

METHODS

This cross-sectional study included 200 people with diabetes at high risk of cardiovascular disease. The main exclusion factor was an estimated glomerular filtration rate < 30 ml/min. Peripheral arterial occlusive disease was diagnosed by colour duplex ultrasonography and peripheral vascular calcification scored by computed tomography scan. We measured sensitivity, specificity, predictive values, accuracy and likelihood ratios of pulse palpation and ankle brachial index, and looked for the impact of calcification on false negative tests (arteriopathy present despite normal screening tests).

RESULTS

Ankle brachial index alone had poor sensitivity and negative predictive value and high negative likelihood ratio. Pulse palpation had higher sensitivity and negative predictive value. An abnormal pulse palpation, defined by weak or missing pulses, combined with an abnormal ankle brachial index, had the highest sensitivity and negative predictive value (92.3 and 89.8%, respectively). Vascular calcification score was higher in patients with false negative tests, for both pulse palpation and ankle brachial index (P < 0.0001 for all). Ankle systolic blood pressure was higher in patients with false negative tests for pulse palpation (P = 0.004).

CONCLUSIONS

Below-knee vascular calcification gave a high rate of false negative results for ankle brachial index. Refined pulse palpation combined with ankle brachial index remained the best strategy to screen for peripheral arteriopathy.

Incidentally detected Monckeberg's sclerosis in a diabetic with coronary artery disease

We report the case of a 62-year-old diabetic man, who was incidentally detected to have extensive calcification in his upper limb arteries, consistent with Monckeberg's sclerosis. The condition was identified when routine radial puncture attempted in the course of coronary angiography was repeatedly unsuccessful. Coronary angiography and angioplasty was subsequently performed through the femoral route. Monckeberg's sclerosis is a poorly understood condition associated with generalised atherosclerosis and chronic kidney disease. The pathogenesis and natural history of Monckeberg's sclerosis are briefly discussed.

Cardiovascular autonomic neuropathy and subclinical cardiovascular disease in normoalbuminuric type 1 diabetic patients

Cardiovascular autonomic neuropathy (CAN) is associated with increased mortality in diabetes. Since CAN often develops in parallel with diabetic nephropathy as a confounder, we aimed to investigate the isolated impact of CAN on cardiovascular disease in normoalbuminuric patients. Fifty-six normoalbuminuric, type 1 diabetic patients were divided into 26 with (+) and 30 without (-) CAN according to tests of their autonomic nerve function. Coronary artery plaque burden and coronary artery calcium score (CACS) were evaluated using computed tomography. Left ventricular function was evaluated using echocardiography. Blood pressure and electrocardiography were recorded through 24 h to evaluate nocturnal drop in blood pressure (dipping) and pulse pressure. In patients +CAN compared with -CAN, the CACS was higher, and only patients +CAN had a CACS >400. A trend toward a higher prevalence of coronary plaques and flow-limiting stenosis in patients +CAN was nonsignificant. In patients +CAN, left ventricular function was decreased in both diastole and systole, nondipping was more prevalent, and pulse pressure was increased compared with -CAN. In multivariable analysis, CAN was independently associated with increased CACS, subclinical left ventricular dysfunction, and increased pulse pressure. In conclusion, CAN in normoalbuminuric type 1 diabetic patients is associated with distinct signs of subclinical cardiovascular disease.

Interrater and intrarater reliability of photoplethysmography for measuring toe blood pressure and toe-brachial index in people with diabetes mellitus

BACKGROUND

A reliable tool to measure arterial flow to the feet in people with diabetes is required given that they are particularly prone to peripheral arterial disease. Traditionally, the ankle brachial index (ABI) has been used to measure arterial circulation, but its application is limited due to calcification of larger arteries. More recently, toe pressure and the toe brachial index (TBI) has been suggested as superior to ABI measurements because they assess smaller digital arteries less prone to arterial calcification. However, reliability studies for the clinical use of photoplethysmography (PPG) in people with diabetes are lacking.

METHODS

Sixty people with diabetes mellitus (35 males and 25 females, mean age 59.6 yrs) consented to take part in the study. The majority (92%) had type 2 diabetes and 8% had type 1 diabetes. Forty-three percent were diagnosed as having peripheral neuropathy when tested using a biothesiometer and 15% were current smokers (10 - 40/day). A podiatrist and a diabetes educator measured toe and brachial blood pressure independently and in a random order using PPG. These measurements were repeated again seven days later, and subsequently analysed with intraclass correlation coefficients (ICC), 95% confidence intervals (CI) and standard error of measurement (SEM).

RESULTS

The intrarater reliability of measuring toe pressures was excellent (ICC3,1 =0.78-0.79, SEM 8 mmHg) and interrater reliability was also excellent (ICC2,2 = 0.93, SEM 4 mmHg). The intrarater reliability for measuring brachial pressures was generally poor (ICC3,1 = 0.40 - 0.42, SEM 19 mmHg) and interrater reliability was fair-good (ICC2,2. 0.65, SEM 14 mmHg). The TBI intrarater reliability was fair-good (ICC3,1 = 0.51-0.72, SEM 0.08), whilst the interrater reliability of TBI was excellent (ICC2,2 = 0.85, SEM 0.07).

CONCLUSIONS

Based on these results, interrater and intrarater reliability of PPG is excellent for measuring toe blood pressure, good for TBI and only fair for brachial pressures in people with diabetes mellitus.

Prevalence of and risk factors for abnormal ankle-brachial index in patients with type 2 diabetes

BACKGROUND

The aim of the present study was to examine abnormalities in the ankle-brachial index (ABI) and related risk factors in patients with type 2 diabetes.

METHODS

Between September 2003 and June 2010, the ABI was determined in 3924 outpatients attending the Diabetes Center of the People's Liberation Army 306th Hospital. In addition, demographic and laboratory data were collected. The risk factors for an abnormal ABI were determined using univariate and stepwise logistic regression analysis.

RESULTS

The ABI was normal (0.91-1.3) in 93.1% of patients, low (<0.9) in 5.2%, and high (>1.3) in 1.7%. The prevalence of abnormal lower ABI was greater in elderly (≥ 65 years) patients (12.2%) than in younger (< 65 years) patients (3.6%). Using normal ABI as the reference, low ABI in younger patients was found to be independently associated with HbA1c, the urinary albumin:creatinine ratio, diabetic peripheral neuropathy, diabetic retinopathy, and cerebrovascular disease. A low ABI in elderly patients was found to be independently associated with age, smoking, HbA1c, uric acid, total cholesterol, diabetic peripheral neuropathy, diabetic retinopathy, diabetic nephropathy and cerebrovascular disease. A high ABI in younger patients was associated with being male.

CONCLUSIONS

The prevalence of an abnormal ABI was high in patients with type 2 diabetes, especially elderly patients. Early identification and intensive treatment are needed to improve the quality of life and overall prognosis of patients with type 2 diabetes.

Use and utility of ankle brachial index in patients with diabetes

Ankle brachial index (ABI) is a simple method to screen peripheral arterial disease (PAD) and to evaluate cardiovascular (CV) prognosis in the general population. Measuring it requires a hand-held Doppler probe but it can be done also with an automatic device. ABI is an effective tool for clinical practice or clinical studies. However, in diabetic patients, it has some specific caveats. Sensitivity of the standard threshold of 0.9 appears to be lower in diabetic patients with complications. Moreover, highly frequent arterial medial calcifications in diabetes increase ABI. It has been demonstrated that measurements >1.3 are well correlated with both an increased prevalence of PAD and CV risk. Therefore, ABI thresholds of less than 0.9 and more than 1.3 are highly suspicious for PAD and high CV risk in diabetic patients. However, when there is concomitant clinical peripheral neuropathy or high risk of arterial calcification, the efficiency of ABI seems to be limited. In this case, other methods should be applied, toe pressure, in particular. Thus, the ABI could be used in patients with diabetes, but values should be interpreted with precision, according to the clinical situation.

Skin fluorescence correlates strongly with coronary artery calcification severity in type 1 diabetes

BACKGROUND

Coronary artery calcification (CAC) is more severe and occurs at an earlier age in type 1 diabetes. Risk factors for this subclinical marker of atherosclerotic burden, like coronary artery disease (CAD) itself, are not fully identified. One postulated mechanism for the increased CAC observed in type 1 diabetes is the accumulation of advanced glycation end products (AGEs). As certain collagen AGEs fluoresce, skin intrinsic fluorescence (SIF) can act as a novel marker of levels of collagen AGEs. We thus sought to determine the relationship between skin intrinsic fluorescence and CAC in type 1 diabetes.

METHODS

One hundred five participants in the Pittsburgh Epidemiology of Diabetes Complications study of childhood-onset (age <17 years) type 1 diabetes who had previously undergone electron beam tomography scanning for CAC (80 of whom had follow-up data) had SIF measurements taken using the SCOUT DM (VeraLight, Inc., Albuquerque, NM). Mean age and diabetes' duration were 49 and 40 years, respectively, at the time of SIF measurement.

RESULTS

Seventy-one percent of the study participants had some measurable CAC that was univariately (but not after age adjustment) cross-sectionally associated with SIF (odds ratio = 2.51, 1.37-4.59). However, for CAC severity using natural logarithmically transformed scores, SIF was both univariately (P < 0.0001) and multivariably (P = 0.03) associated with CAC. This relationship was independent of age, a history of CAD, renal function, or renal damage. Receiver operator characteristic analyses revealed that the discriminative ability of SIF to detect CAC went from an area under the curve of 71% for the presence of any CAC to 85% for those with a CAC score >400.

CONCLUSIONS

The relationship between SIF and CAC appears stronger with more severe calcification. Given the strong relationship of CAC with CAD this finding has important implications and suggests that SIF maybe a useful marker of CAC/CAD risk and potentially a therapeutic target.

Medial arterial calcification in diabetes and its relationship to neuropathy

Calcification of the media of arterial walls is common in diabetes and is particularly associated with distal symmetrical neuropathy. Arterial calcification also complicates chronic kidney disease and is an independent risk factor for cardiovascular and all-cause mortality. The term calcification is not strictly accurate because the morphological changes incorporate those of new bone formation, i.e. ossification. The processes are complex, but are closely related to those involved in bone homeostasis, and it is relevant that calcification of the arterial wall and osteopenia often co-exist. One particular factor linked to the development of arterial calcification is distal symmetrical neuropathy; indeed, it has been suggested that neuropathy explains the distal distribution of arterial calcification in diabetes. It has also been suggested that the link with neuropathy results from loss of neuropeptides, such as calcitonin gene-related peptide, which are inherently protective. The association between distal symmetrical neuropathy and calcification of the arterial wall highlights the fact that neuropathy may be an independent risk factor for cardiovascular mortality.

Charcot arthropathy of the foot and ankle: modern concepts and management review

Charcot arthropathy (Charcot neuroarthropathy, diabetic neuropathic osteoarthropathy, or neuropathic arthropathy) remains a poorly understood disease, although recent research has improved our level of knowledge regarding its etiology and treatment. The effects of Charcot arthropathy are almost exclusively seen in the foot and ankle, and the diagnosis is commonly missed upon initial presentation. It has been well established that this complication of diabetes mellitus severely reduces the overall quality of life and dramatically increases the morbidity and mortality of patients. However, there are few high-level evidence studies to support management and treatment options at this point in time. The goal of this study is to evaluate the modern concepts of Charcot arthropathy through a review of the available literature and to integrate a perspective of management from the authors' extensive experience.

Mönckeberg sclerosis revisited: a clarification of the histologic definition of Mönckeberg sclerosis

CONTEXT

Medial calcification of muscular arteries is known as Mönckeberg sclerosis (MS). Although this was first described in 1903, disagreement persists over its precise histologic appearance. Some, including Mönckeberg, have written that the media alone are calcified, whereas others maintain that both the media and internal elastic lamina (IEL) are involved. Since vascular calcification is of great interest to investigators and clinicians, defined criteria for classifying calcified arterial lesions are important.

OBJECTIVE

To clarify the histologic definition of MS with regard to calcification of the IEL.

DESIGN

We reviewed slides from 14 incisional and excisional surgical biopsies and autopsy specimens containing arteries with previously diagnosed MS. We looked specifically for medial and IEL calcification and used von Kossa, alizarin red, and trichrome/elastic stains to confirm our findings. We also performed a literature search on the histologic appearance of MS.

RESULTS

Both medial and IEL calcification were present in all specimens. Medial calcification extended alongside calcified IEL. In focal regions, calcification appeared limited to the IEL, with minimal medial calcification. Occasionally, calcified nodules in the media appeared separated from the IEL yet were connected to it in other planes of section. Despite these variations in appearance, IEL involvement was universal. Of 25 journal articles and texts, 10 state that MS involves the IEL with calcification, whereas 15 state or suggest that it does not.

CONCLUSIONS

Our findings indicate MS involves both the IEL and media with calcification in spite of inconsistencies on this point in the medical literature.

Diabetic foot disease in the elderly

Elderly diabetic patients are particularly burdened by foot disease. The main causes for foot disease are peripheral neuropathy, foot deformities and peripheral arterial disease (PAD). Other risk factors include poor vision, gait abnormalities, reduced mobility an medical co-morbidities. The risk of major amputations increases with age, along with the increased prevalence of these risk factors. Th true risk of amputation and other burdens of foot disease in the elderly are likely underestimated by current epidemiological data. Th prevalence of neuropathy, foot deformities and PAD as well as the risk of amputation all increase with age even in non-diabetic patients. The principles of prevention and management of diabetic foot disease may also apply to large segments of the elderly non-diabetic population. Foot ulcer prevention relies on the identification of high risk patients and avoidance of triggering events, such as ill-fitting shoes, walking barefoot or poor self-care. PAD is a major cause of amputation and should be prevented by lifelong attention to glycaemic control, treatment of hypertension and dyslipidemia, and avoidance of smoking. The treatment of foot ulcers relies on pressure relief (off-loading), wound debridement, and treatment of infection and ischemia. It requires an individualized approach considering the patient's co-morbidities and functional status. Off-loading remains essential, but devices such as total contact casts or crutches can only rarely be implemented. However, providing adapted standard foot-wear and insisting on its consistent use even at home is often effective. The benefits of aggressive vascular or orthopaedic surgery should be weighed against the risks of prolonged hospitalisation and resulting functional decline. Greater attention to prevention and individualized care are needed to reduce the burden of diabetic foot disease in the elderly.

The functional cardiovascular consequences of vascular calcification

Calcification of the cardiovascular system is now well recognized to be a common feature of patients with chronic kidney disease. It is increasingly prevalent in patients with more severe uremia, particularly those receiving dialysis. Furthermore, it is progressive in terms of both severity and associated functional cardiovascular consequences. Although well recognized to be associated with a markedly increased mortality rate, the pathophysiological processes that result in these poor outcomes are less well understood. This article attempts to review calcification of the cardiovascular system as a whole entity and how the structural and functional changes may translate to the observed patterns of disease seen in these patients.

Mönckeberg's sclerosis - is the artery the only target of calcification?

BACKGROUND

Since its first description, Mönckeberg's sclerosis has only been related to arterial media calcification, being listed among the primary diseases of the vessels.

CASE PRESENTATION

We report here a clinically and histologically confirmed case of Mönckeberg's sclerosis in which the patient presented with massive areas of soft tissue calcifications in the pharynx and larynx. Polysomnographic parameters showed severe obstructive apnea refractory to nasal continuous positive airway pressure. Clinical and laboratory findings excluded concomitant endocrine or rheumatological diseases.

CONCLUSION

Our data provide a new insight about Mönckeberg's sclerosis, i.e., the fact that the etiopathogenic process involved in the phenomenon of calcification may not be restricted only to the arteries, but may occur in the entire organism. Further studies of the etiopathogenesis of this disease are needed.

Theories concerning the pathogenesis of the acute charcot foot suggest future therapy

The acute Charcot foot is characterized by bone fracture and dislocation, and is a rare complication of distal symmetrical neuropathy in diabetes. The cause is unknown, but it cannot be attributed solely to loss of protective sensation. However, recent advances in understanding the mechanisms of osteoclast activation have suggested that the key abnormality may lie in an enhanced inflammatory response to injury, which is itself linked to increased bone lysis. The recognition that the acute Charcot foot is essentially an inflammatory arthropathy suggests new options for the management of this potentially devastating condition.

An evaluation of the efficacy of methods used in screening for lower-limb arterial disease in diabetes

OBJECTIVE

Foot-related disease is the most common cause for hospital admission among the diabetic population. Lower-limb peripheral arterial occlusive disease (PAOD) is a major risk factor in diabetic foot disease. Screening for PAOD commonly includes foot pulses and the ankle-brachial pressure index (ABPI) and/or the toe-brachial pressure index (TBI), but concerns persist regarding their accuracy. We evaluated the efficacy of several commonly used screening methods in different subject populations.

RESEARCH DESIGN AND METHODS

We studied 130 limbs in 68 individuals with no critical ischemia over 8 months. Limbs were grouped on the basis of the presence or absence of diabetes, clinically detectable peripheral neuropathy, and PAOD identified on color duplex imaging. Comparative analyses of foot pulses, the ABPI, the TBI, and distal Doppler waveform analysis were performed.

RESULTS

Foot pulses, the TBI, and qualitative waveform analyses were highly sensitive screening methods in individuals with and without diabetes. However, detectable peripheral neuropathy was associated with a reduced sensitivity and poor specificity of foot pulses, a reduction in sensitivity of the ABPI (71 to 38%), and a reduction in specificity of the TBI (81 to 61%) and qualitative waveform analysis (96 to 66%). Quantitative analysis failed to detect disease with severely damped and low-intensity signals.

CONCLUSIONS

Screening tools that are effective in screening for lower-limb PAOD in the nondiabetic population are less efficacious in diabetes, particularly in the presence of detectable peripheral neuropathy. Qualitative waveform analysis and the TBI were demonstrated to be more effective screening methods than the ABPI and foot pulses particularly in high-risk limbs with detectable peripheral neuropathy.

Reduced baroreflex sensitivity is associated with increased vascular calcification and arterial stiffness

INTRODUCTION

Vascular calcification is a critical determinant of cardiovascular morbidity and mortality in chronic haemodialysis (HD) patients. The pathophysiology underlying this observation remains obscure. Baroreceptor sensitivity (BRS) is important in the maintenance of an appropriate cardiovascular status both at rest and under the physiological stress of HD. BRS is determined by both the mechanical properties of the vascular wall, mediating the transfer of transmural pressure, and afferent and efferent autonomic function. We aimed to study the association between arterial structure, function and BRS in chronic HD patients.

METHODS

We studied 40 chronic HD patients mean age 62+/-2 (26-86) years who had received HD for a mean 40+/-4 (9-101) months. Spontaneous BRS was assessed using software studying the relationship between inter-beat variability and beat to beat changes in systolic blood pressure. Functional characteristics of conduit arteries (pulse wave analysis) were studied with applanation tonometry at the radial artery. Arterial calcification was assessed in lower limbs using reconstructed multi-slice computed tomography and quantified with volume-corrected calcification scores within the superficial femoral artery.

RESULTS

Mean BRS was 4.43+/-0.44 ms/mmHg, with a wide range from 1.0 to 11.5 ms/mmHg. This correlated with arterial stiffness as measured by time to shoulder calculated from the central pulse wave analysis (r = 0.4, P = 0.01). BRS was also associated with vascular calcification (P = 0.01) but not by other factors such as dialysis vintage, age or pre-dialysis systolic/diastolic blood pressure.

CONCLUSION

The reduction in BRS and the resulting aberrant blood pressure response to the physiological stress and volume changes of HD may be important in the further understanding of the pathophysiology of the increased mortality in HD patients with vascular calcification.

Vascular calcification and osteolysis in diabetic neuropathy-is RANK-L the missing link?

Diabetic neuropathy is associated with osteopenia and calcification of vascular smooth muscle cells. These changes are most marked in patients with acute neuropathic osteoarthropathy (Charcot foot), in which osteopenia is universal and the prevalence of vascular calcification exceeds 90%. While it has been thought that both osteopenia and vascular calcification may be linked to sympathetic denervation with increased peripheral limb perfusion, the cellular mechanism was not clear. However, the recent recognition that the receptor activator of nuclear factor kappa B ligand (RANK-L)/osteoprotegerin (OPG) signalling pathway is central to the processes regulating bone turnover in a wide variety of medical conditions has raised the possibility that the same cytokines may be involved in the osteolysis which accompanies diabetic neuropathy. This is made more likely by the realisation that the RANK-L/OPG pathway is also thought to mediate the calcification of vascular smooth muscle cells in coronary and peripheral vascular disease. The circumstantial evidence underpinning this hypothesis is reviewed here, and it is suggested that the unregulated activation of RANK-L-mediated effects on bone and arteries may be triggered by the loss of nerve-derived peptides, e.g. calcitonin gene-related peptide, which normally exert a moderating influence on the pathway.

Genetic determinants of arterial calcification associated with atherosclerosis

Increasing research interest has focused on arterial calcification in the setting of atherosclerosis. Many features of atherosclerosis-related calcification provide useful clinical information. For example, calcium mineral deposits frequently form in atherosclerotic plaque, and intimal arterial calcification can be used as a surrogate marker for atherosclerosis; also, calcium deposits are readily and noninvasively quantified, which is useful because greater amounts of coronary calcification predict a higher risk of myocardial infarction and death. Several mechanisms leading to calcification associated with atherosclerosis have been proposed; however, no direct testing of proposed mechanisms has yet been reported. Studies in genetically altered animals and in humans have shed light on potential genetic determinants, which in turn could form the basis for a more comprehensive understanding of the factors affecting calcification within plaque and the associated pathobiologic implications. We review proposed molecular and cellular mechanisms of atherosclerosis-associated arterial calcification, summarize genetic influences, and suggest areas in which further investigation is needed. Understanding the molecular and genetic determinants of specific structural plaque components such as calcification can provide a solid foundation for the development of novel therapeutic approaches to favorably alter plaque structure and minimize vulnerability to arterial rupture.

Aortic distensibility is reduced in subjects with type 2 diabetes and cardiac autonomic neuropathy

BACKGROUND

Reduced aortic distensibility predicts cardiovascular mortality in patients with type 2 diabetes and impaired glucose tolerance. Cardiac autonomic neuropathy is common in subjects with diabetes. However, the relationship between the elastic properties of the aorta and autonomic neuropathy has not been studied to date in subjects with type 2 diabetes.

MATERIALS AND METHODS

In this cross-sectional study, a total of 87 subjects with type 2 diabetes (27 with and 60 without cardiac autonomic neuropathy) as well as 60 healthy individuals, matched for age and sex with the diabetic subjects, were examined. Cardiac autonomic neuropathy was diagnosed on the basis of the battery of the classic cardiovascular autonomic function tests. Aortic distensibility was assessed by high-resolution ultrasonography.

RESULTS

Diabetic patients had reduced aortic distensibility in comparison with the control subjects: 1.81 +/- 0.58 vs. 2.53 +/- 0.34 10-6 cm2 dyn-1, respectively (P < 0.0001). In addition, diabetic individuals with cardiac autonomic neuropathy had reduced aortic distensibility as compared with patients without this complication: 1.60 +/- 0.72 vs. 1.90 +/- 0.48 10-6 cm2 dyn-1, respectively (P = 0.02). Multivariate linear regression analysis in the diabetic group, after controlling for a number of confounding factors such as age, systolic and diastolic blood pressure, duration of diabetes and presence as well as severity of cardiac autonomic neuropathy, demonstrated a significant and independent association between duration of diabetes [B = -0.02, SE(B) = 0.01, P = 0.01] and presence of cardiac autonomic neuropathy [B = -0.29, SE(B) = 0.14, P = 0.03] with aortic distensibility.

CONCLUSION

Type 2 diabetes is associated with a significant reduction in the elastic properties of the aorta. In addition, known duration of diabetes and presence of cardiac autonomic neuropathy are the main predictors of aortic distensibility in subjects with type 2 diabetes.

Relationship of medial arterial calcinosis to autonomic neuropathy and adverse outcomes in a diabetic veteran population

STATEMENT OF THE PROBLEM

Medial arterial calcinosis (MAC) is associated with neuropathy, amputation, and mortality through an unknown mechanism. We hypothesized that MAC was a marker of autonomic neuropathy rather than a risk factor and that the outcomes were due to autonomic neuropathy.

METHODS

All subjects in an ongoing prospective study of diabetic foot conditions in a diabetic veteran cohort who received a foot radiograph between 11/7/90 and 11/5/93 were included. Autonomic neuropathy measured as either heart rate variability with timed respiration or postural hypotension. A logistic model predicted the presence of MAC at baseline and Cox proportional models assessed the relative contribution of autonomic neuropathy and traditional risk factors for the outcomes of ulceration, amputation, and death.

RESULTS

MAC was identified in 181 subjects, no MAC in 253 subjects, and 39 were excluded due to disagreement between observers. Both measures of autonomic neuropathy were independent predictors of MAC at baseline, even after adjustment for vibration sensation loss in a logistic model. MAC was associated with an increased risk for ulceration (hazards ratio, HR: 2.1, 95% confidence intervals, CI, 1.4-3.1), amputation (HR 3.3, 95% CI 1.5-7.4), and mortality (HR 1.6, 95% CI 1.1-2.2). The addition of either autonomic measure of neuropathy did not change the MAC HR or significantly improved the fit of the model.

CONCLUSIONS

Our hypothesis that the excess mortality, amputation, and ulceration in persons with MAC could be explained by autonomic neuropathy measured as postural hypotension or heart rate variability with measured respiration was not supported.

Increased arterial wall stiffness limits flow volume in the lower extremities in type 2 diabetic patients

OBJECTIVE

To document an association between arterial wall stiffness and reduced flow volume in the lower-extremity arteries of diabetic patients.

RESEARCH DESIGN AND METHODS

We recruited 60 consecutive type 2 diabetic patients who had no history or symptoms of peripheral arterial disease (PAD) in the lower extremities and normal ankle/brachial systolic blood pressure index at the time of the study (non-PAD group) and 20 age-matched nondiabetic subjects (control group). We used an automatic device to measure pulse wave velocity (PWV) in the lower extremities as an index of arterial wall stiffness. At the popliteal artery, we evaluated flow volume and the resistive index as an index of arterial resistance to blood flow using gated two-dimensional cine-mode phase-contrast magnetic resonance imaging.

RESULTS

Consistent with previous reports, we confirmed that the non-PAD group had an abnormally higher PWV compared with that of the control group (P < 0.001). To further demonstrate decreased flow volume and abnormal flow pattern at the popliteal artery in patients with a higher degree of arterial wall stiffness, we assigned the 60 non-PAD patients to tertiles based on their levels of PWV. In the highest group, magnetic resonance angiograms of the calf and foot arteries showed decreased intravascular signal intensity, indicating the decreased arterial inflow in those arteries. The highest group was also characterized by the lowest late diastolic and total flow volumes as well as the highest resistive index among the groups. From stepwise multiple regression analysis, PWV and autonomic function were identified as independent determinants for late diastolic flow volume (r(2) = 0.300; P < 0.001).

CONCLUSIONS

Arterial wall stiffness was associated with reduced arterial flow volume in the lower extremities of diabetic patients.

TBI or not TBI: that is the question. Is it better to measure toe pressure than ankle pressure in diabetic patients?

AIMS

Measurement of ankle blood pressure is a simple method of assessing lower limb arterial blood supply. However, its use in diabetes has been questioned due to the presence of medial artery calcification. Measurement of toe blood pressure has been advocated as an alternative but it is technically more difficult. The aim of this study was to obtain information to guide clinicians as to when pressure measurements should be taken at the toe.

METHODS

Ankle brachial index (ABI) and toe brachial index (TBI) were measured by Doppler ultrasound, or photoplethysmography on 174 subjects with diabetes and 53 control subjects. The Bland and Altman method, and the Cohen's method of measuring agreement between two tests were used to compare ABI with TBI.

RESULTS

The mean differences between ABI and TBI in control and diabetic subjects are 0.40 +/- 0.13 and 0.37 +/- 0.15, respectively. Nearly all diabetic patients with an ABI < 1.3 have an ABI-TBI gradient falling within the normal range established from the non-diabetic cohort. In contrast, the majority of diabetic subjects with an ABI > or = 1.3 have ABI-TBI differences outside this range. When patients are categorized according to ABI and TBI, there is also good agreement between the tests when ABI is low or normal (84% and 78% agreement, respectively), but not when ABI is elevated.

CONCLUSION

In the majority of patients with diabetes, assessment of TBI conveys no advantage over ABI in determining perfusion pressure of the lower limbs. Only in those patients with overt calcification, which gives an ABI > or = 1.3, are toe pressure measurements superior. This guideline should simplify assessment and treatment of diabetic patients with disease of the lower limbs. Diabet. Med. 18, 528-532 (2001)

The association of heart-rate variability with cardiovascular risk factors and coronary artery calcification: a study in type 1 diabetic patients and the general population

OBJECTIVE

To examine the association of heart-rate variability with cardiovascular risk factors and coronary calcification in type 1 diabetic and nondiabetic subjects without a history of cardiovascular disease. Reduced heart-rate variability is associated with increased risk of coronary events. Whether it is associated with coronary atherosclerosis is unknown.

RESEARCH DESIGN AND METHODS

Power spectral analysis was used to define heart-rate variability in a cross-sectional study of 160 type 1 diabetic patients and 163 randomly selected nondiabetic adults from the general population aged 30-55 years. Coronary artery calcification was measured using electron beam-computed tomography.

RESULTS

Reduced heart-rate variability was associated with similar risk factors in the diabetic and nondiabetic subjects, namely higher HbA(1c), triglycerides, systolic blood pressure, BMI, and albumin excretion rate. Reduced heart-rate variability was significantly associated with coronary artery calcification in all subjects (odds ratio per tertile lower total power = 1.5, P = 0.01). This association was not independent of blood pressure or BMI (odds ratio on adjustment = 1.3, P = 0.1).

CONCLUSIONS

Reduced heart-rate variability clusters with other cardiovascular disease risk factors, especially those that are more common in the insulin resistance syndrome, and is associated with increased coronary calcification in asymptomatic young adults. Whether reduced heart-rate variability leads to other risk factor disturbances or mediates the effects of other risk factors on atherosclerosis deserves further study.

Medial arterial calcification is frequently found in patients with microalbuminuria

The presence of medial arterial calcification (MAC), often referred to as Moncheberg's sclerosis, was sought in patients with long-standing diabetes mellitus. One hundred patients aged 22-50 years were initially divided into two groups, those with neuropathy and those without. As expected, the incidence of MAC was significantly higher in the neuropathy group (40% vs. 20%). When the patients were divided into two groups, those with MAC and those without, it appeared that the incidence of MAC was very high in patients who had microalbuminuria (57% vs. 13%) and particularly when microalbuminuria was combined with neuropathy (40% vs. 7%). It is concluded that microalbuminuria is a strong predicting factor of medial arterial sclerosis independent of neuropathy.