Medial arterial calcification is frequently found in patients with microalbuminuria

Association between Urine Albumin-to-Creatinine Ratio within the Normal Range and Incident Hypertension in Men and Women

PURPOSE

There have been few studies on gender difference in the impact of a urine albumin-to-creatinine ratio (UACR) within the normal range on the risk of hypertension. We evaluated whether the association between the UACR below the microalbuminuria range and the incident risk of hypertension is different between men and women.

MATERIALS AND METHODS

A total of 1173 individuals (442 men and 731 women) aged 40 to 70 years without hypertension was examined at baseline (2005-2008) and followed (2008-2011). We defined the UACR as the amount of albumin (mg/dL) divided by creatinine (g/dL) in randomly voided urine. The subjects were classified according to UACR tertile.

RESULTS

During an average of 2.6 years of follow-up, 57 men (12.9%) and 66 women (9.0%) developed hypertension. In multivariable-adjusted models, the odds ratio for new-onset hypertension comparing the highest and lowest tertiles of UACR was 1.83 [95% confidence interval (CI) 0.85-3.94] in men and 2.69 (95% CI 1.27-5.73) in women. In stratified analyses by menopausal status, higher tertiles of UACR were associated with an increased risk of incident hypertension in postmenopausal women.

CONCLUSION

Higher normal UACR levels were associated with an increased risk of incident hypertension in women. The UACR could have a clinical role in predicting the development of hypertension.

Monckeberg's Arteriosclerosis of the Liver and Spleen Demonstrated by Ultrasound

There are three types of arteriosclerosis (hardening of the arteries): atherosclerosis, Monckeberg's arteriosclerosis, and arteriolosclerosis. The features of central large-vessel atherosclerosis are familiar and frequently depicted at sonography of the carotid arteries and abdominal aorta. Monckeberg's arteriosclerosis is not often encountered during ultrasound examinations. The authors report a case of Monckeberg's arteriosclerosis demonstrated by sonography. Its pathogenesis and distinctive imaging findings are described.

Toe blood pressure and toe-brachial index

TBP and TBI are considered more accurate in assessing lower extremity perfusion in those patients with a falsely elevated ABI suspected from medial arterial calcification. Like the ABI, a TBI may be obtained by the nurse through a similar procedure using a sphygmomanometer and hand-held Doppler. Knowledge by the vascular nurse of this noninvasive technique will assist in a more timely recognition of PAD and may improve long-term patient outcomes.

Association of albumin-creatinine ratio and cystatin C with change in ankle-brachial index: the Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND

Low ankle-brachial index (ABI) is a reflection of atherosclerotic disease, and high ABI is an indicator of calcified vessels. The associations of albuminuria and cystatin C level with incidence of either low or high ABI are unknown.

STUDY DESIGN

Prospective longitudinal cohort study.

SETTING & PARTICIPANTS

MESA (Multi-Ethnic Study of Atherosclerosis) enrolled community-dwelling adults (N=6,814) aged 45-84 years who were free of clinical cardiovascular disease at baseline.

PREDICTORS

Baseline albumin-creatinine ratio (ACR) and serum cystatin C level.

OUTCOMES

Development of low (<0.90), and high (>1.40) ABI using multinomial regression among persons with ABI of 0.90-1.40 at baseline.

RESULTS

During 9.8 years of follow-up, 221 and 89 participants progressed to low and high ABIs, respectively. Baseline ACR and cystatin C level were higher among progressors compared with nonprogressors. In multivariable analyses, doubling of ACR was associated with increased risk of progression to low (OR, 1.08; 95% CI, 0.99-1.20) and high (OR, 1.16; 95% CI, 1.01-1.32) ABIs. Compared to the lowest quintile, the highest quintile of ACR had a significantly increased risk of progression to low (OR, 1.79; 95% CI, 1.03-3.12) and high (OR, 2.76; 95% CI, 1.32-5.77) ABIs. Higher cystatin C levels were associated with progression to low (OR per 1-SD greater, 1.12; 95% CI, 1.00-1.26) but not high (OR per 1-SD greater, 1.01; 95% CI, 0.81-1.25) ABI, but the highest quintile of cystatin C was not associated independently with either outcome.

LIMITATIONS

Single measure of albuminuria and low number of progressors to high ABI.

CONCLUSIONS

In adults free of clinical cardiovascular disease, albuminuria was a strong independent risk factor for the development of both high and low ABIs, important and different measures of peripheral artery disease.

High normal urine albumin-to-creatinine ratio predicts development of hypertension in Korean men

BACKGROUND

Microalbuminuria is known as a risk factor for hypertension. Recently it was suggested that urine albumin-to-creatinine ratio (UACR), even within the normal range, can be associated with hypertension, but the temporal relationship between normal range UACR and hypertension was not confirmed. Therefore the aim of this study was to verify an association between normal range UACR and the development of hypertension in Korean men.

METHODS AND RESULTS

This prospective cohort study was performed on 1,284 initially non-hypertensive Korean men. The total follow-up period was 4,109.5 person-years and the mean follow-up period was 3.2±1.51 years. Cox proportional hazards model was used to estimate the hazard ratios (HR) for the risk of hypertension development. After adjusting for multiple covariates, the HR (95% confidence interval [CI]) for incident hypertension, comparing the second to the fourth quartiles of UACR level to the first quartile, were 1.35 (95% CI: 0.93-1.97), 1.55 (95% CI: 1.07-2.25) and 1.89 (95% CI: 1.31-2.71), respectively (P for trend=0.001).

CONCLUSIONS

High UACR within the normal range was significantly associated with hypertension development. Furthermore, this association remained significant after adjusting for multiple baseline covariates. 

Factors Associated With Calcification in the Pedal Arteries in Patients With Diabetes and Neuropathy Admitted for Foot Disease and Its Clinical Significance

The aim of this study was to determine the factors associated with calcification in the pedal arteries (CPAs) in a population of patients with diabetes admitted for acute foot disease and to find whether the presence of CPAs had any influence on the short-term outcomes. Electronic charts were retrospectively reviewed for patients admitted to our department for acute diabetic foot problems between January 1, 2008, and December 31, 2012. Digital images of the plain x-rays, which were performed on patients during this period, were reviewed. Patients were classified into 2 groups: those with absence (group 1) and presence of CPAs (group 2). One hundred and sixty-five patients were included in the present study. Ninety-eight (59.4%) patients had CPAs in the plain x-rays. The predictive variables related to the presence of CPAs were duration of diabetes >20 years (odds ratio [OR] = 2.1, 95% confidence interval [CI] = 1.0-4.3), retinopathy (OR = 2.2, 95% CI = 1.0-4.6), albuminuria (OR = 3.3, 95% CI = 1.5-7.4), and peripheral arterial disease (OR = 4.2, 95% CI = 2.0-8.7). Fifty-six patients underwent amputation (33.9%): 13 (19.4%) in group 1 and 43 (43.9%) in group 2 ( P < .01). Thirty-four patients (20.6) required reoperation: 6 (9%) in group 1 and 28 (28.6%) in group 2 ( P < .01). In conclusion, the predictive variables related to the presence of CPAs in a series of patients admitted for foot disease were duration of diabetes >20 years, retinopathy, albuminuria, and peripheral arterial disease. Differences in the outcomes were related to the association of CPAs with peripheral arterial disease.

Prevalence and progression of peripheral vascular calcification in type 2 diabetes subjects with preserved kidney function

AIMS

To determine predictors of prevalence and progression of peripheral vascular calcification (VC) in type 2 diabetes (DM) subjects with preserved kidney function.

METHODS

Fifty-eight subjects (age 63 ± 11.6 years) with type 2 DM and serum creatinine <125 μmol/l were studied. A CT scan of femoral, posterior tibial and dorsalis pedis arteries was carried out at baseline and at one year. Serum osteoprotegerin (OPG) and RANKL were measured along with routine biochemistry.

RESULTS

Seventy-eight percent of patients had baseline VC, 47% with femoral VC, 49% with VC at two sites - femoral and foot, and 4% foot VC alone. Age, ethnicity, peripheral neuropathy and eGFR were independent predictors of baseline VC. Baseline calcification was the most important predictor of VC progression and was present in all subjects with progression compared to 35% of non-progressors (p < 0.001). Exclusion of demographic factors from models revealed neuropathy and serum OPG levels as independent predictors of both; baseline VC and progression.

CONCLUSIONS

Subjects with type 2 DM and well-preserved renal function had a high prevalence of VC, which was rapidly progressive especially in those with baseline VC. Age, ethnicity, neuropathy, smoking and eGFR were predictors of baseline VC and progression.

The foot in type 2 diabetes: is there a link between vascular calcification and bone mineral density?

AIMS

To examine the relationship between vascular calcification in the foot (FVC) and bone mineral density (BMD) in the heel of type 2 diabetes mellitus (DM) subjects.

METHODS

65 subjects with type 2 DM and serum creatinine<125 μmol/l underwent CT scanning of the foot to assess FVC and dual energy X ray absorptiometry (DEXA) scan to assess heel BMD. Routine biochemistry including osteoprotegerin (OPG) and Receptor activator of nuclear factor kappa-B ligand (RANKL) was also carried out.

RESULTS

The proportion of subjects with FVC was 43%, whilst 40% had low BMD (T score<-1.0). Age, neuropathy and 25 hydroxyvitamin D were independent predictors of FVC. Body-weight, eGFR, 25 hydroxyvitamin D, OPG, and total cholesterol were independent predictors of low heel BMD. There was no correlation between albuminuria and BMD or FVC. There was no difference in heel BMD between those with FVC and those without, but those with frank osteoporosis were significantly more likely to have FVC than those with higher BMD.

CONCLUSIONS

There is no clear-cut association between FVC and low BMD in type 2 DM with relatively well-preserved renal function. Age, neuropathy, eGFR, hyperlipidemia, body-weight, 25 hydroxyvitamin D and OPG play a complex role in their pathogenesis.

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.

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 neuro-osteoarthropathy

The classical neurotraumatic and neurotrophic theories for the pathogenesis of the acute Charcot neuro-osteoarthropathy (CN) in diabetes, do not address certain key features of the disease. These features include the facts that the condition usually affects just one side, that it is self-limiting, and that it is also very uncommon. Similarly, it is not known to what extent the condition may depend, as suggested by Jean-Martin Charcot, on pre-morbid osteopenia. Recent advances in understanding the mechanisms underlying the pathogenesis of osteopenia and osteoporosis and the central role of the RANKL/OPG signalling system have, however, suggested the possible involvement of other factors in the evolution of the disease. Specifically, it has been suggested that acute CN may be triggered in a susceptible individual by any event that leads to localized inflammation in the affected foot. This local inflammation leads to a vicious cycle in which there is increasing inflammation, increasing expression of RANKL, and increasing bone breakdown. The likely central role for the RANKL/OPG pathway suggests new possibilities for future treatments.

The causes of the Charcot syndrome

The Charcot syndrome is a rare complication of neuropathy in diabetes and is characterized by an acute inflammatory episode of the foot that is associated with variable degrees of dislocation, fracture, and deformity. It has no single cause but represents the final common pathway in people who are predisposed to its development by the varying overlap of several different factors. The association of the active phase of the disease with inflammation, increasing osteopenia, and increasing calcification of the arterial walls strongly suggests, however, the involvement of the receptor activator of nuclear factor-kappaB ligand (RANKL)/osteoprotegerin (OPG) cytokine pathway, which is closely involved in all three processes. The evidence for increased expression of RANKL and OPG in diabetes and neuropathy as well as its potential significance is reviewed.

VASCULAR CALCIFICATION IN PATIENTS WITH KIDNEY DISEASE: Cardiovascular Calcification in Nondialyzed Patients with Chronic Kidney Disease

Chronic kidney disease (CKD) has become a major health-care problem of global proportions. Progression to end-stage renal disease (ESRD), the need for renal replacement therapy, and the high annual death rate of dialysis patients are the most noticeable outcomes of CKD. Less appreciated, however, is the fact that most patients with CKD actually die mainly from cardiovascular disease, rather than progress to ESRD. Coronary artery calcification (CAC), a surrogate marker of atherosclerosis, is common in dialysis and CKD patients. Coronary artery calcium scores, as measured by ultrafast computed tomography, is an independent predictor of future cardiac events. Using this technique, several studies have documented extensive calcification in dialysis patients, a subject of several exhaustive reviews. Unfortunately, much less attention has been paid to calcification in nondialyzed patients with CKD. In this review, I will emphasize the fact that CVC is common in patients with CKD not yet on dialysis, develops early in the course of CKD, and worsens with the decline in renal function particularly among diabetics who progressed to ESRD. I will also discuss the pathogenesis of CVC in CKD patients and highlight the lack of a major role for abnormalities of mineral metabolism in the pathogenesis of calcification in CKD patients. In addition to the high prevalence of traditional risk factors for CAD, the presence of proteinuria, reduced renal function, diabetic nephropathy, and the rate of progression to ESRD may represent the main uremia-related factors that increase the risk for calcification in CKD. Finally, I will review the protective role of inhibitors of calcification in CKD.

Lower-extremity arterial calcification as a correlate of coronary artery calcification

Coronary artery calcification (CAC) has been used as a testing modality for coronary atherosclerosis burden. In diabetes, arterial calcification in the tunica media is common and predicts renal and cardiovascular mortality. It is unknown whether the 2 calcification processes are related. We identified risk factors associated with lower-extremity arterial calcification (LEAC) and determined its relationship to the presence of CAC 6 years later and the incidence of complications in type 1 diabetes mellitus. A random sample of 190 participants from the Pittsburgh Epidemiology of Diabetes Complications Study, a prospective cohort of childhood-onset type 1 diabetes mellitus, received radiographs of their ankles and feet at the 4-year follow-up examination (1990-1992) and was followed up for approximately 6 years. At the 10-year examination, 121 of these individuals received an electron beam tomography scan. Male sex (odds ratio [OR] = 12.72, P < .0001), diabetes duration (OR = 4.53, P < .0001), and autonomic neuropathy (AN; OR = 5.92, P = .007) independently increased the odds of LEAC. Controlling for other known risk factors (duration and high-density lipoprotein cholesterol), we found that LEAC correlated with the presence of CAC 6 years later (OR = 1.12, P = .03), although adjusting for neuropathy attenuated this relationship (P = .08). LEAC also independently predicted AN but not the onset of other diabetes complications. Although arterial calcification in the lower extremities and the heart share many of the same risk factors, LEAC is an independent correlate of the later presence of CAC and AN. Thus, factors related to the calcification process in addition to vascular risk factors may play a role in determining the extent of CAC.

Artériolopathie calcique (Calciphylaxie)

PURPOSE

Calcific arteriolopathy (CA), also known as " Calciphylaxis " describes a phenomenon of necrosis, mainly cutaneous and sometimes systemic, due to the obliteration of the arteriole's lumen. Initially there are under-intimal calcium deposits, and then the thrombosis occurs leading to the necrosis. CA affects mainly the renal insufficient hemodialysed patient, but not exclusively. We present 4 cases which illustrate well the etiologic spectrum of CA: terminal renal insufficiency, neoplasia, primary hyperparathyroidism, proteinuria, vitamin K inhibitors. We describe the AC's epidemiology, its cutaneous and systemic clinical presentations, its treatment. We make the hypothesis that CA is a strong risk marker in matter of cardiac mortality and we discuss this point.

CURRENT KNOWLEDGE AND KEY POINTS

In this article we describe the numerous breakthroughs that have been made in matter of research about calcification over the past few years: inhibitors of calcium phosphate deposition, vitamin D and PTH1R, protein-calcium complexes, cell death, induction of bone formation. These data are analysed from a clinical point of view with practical purposes. We present CA not only as a cutaneous disease but as a systemic pathology.

FUTURE PROSPECTS AND PROJECTS

The CA epidemiology is an incentive to more diagnosis suspicion in front of organ infarct involving a patient likely to be concerned by CA. The scientific and therapeutic breakthroughs in matter of calcification enable a better prevention of the disease. Nevertheless it remains very difficult to cure when installed.

Cardiovascular calcification in Hispanic Americans (HA) with chronic kidney disease (CKD) due to type 2 diabetes

BACKGROUND

Cardiovascular calcification (CVC) is common and severe in patients with end-stage renal disease on dialysis. However, the prevalence and severity of CVC is less well documented in patients with chronic kidney disease (CKD) not yet on dialysis.

METHODS

Fifty-eight nondialyzed HA with type 2 diabetes and CKD were enrolled. They comprise 29 patients with stages 1 and 2 CKD (early CKD group) and 26 patients with stages 4 and 5 CKD (advanced CKD group). Coronary artery calcification (CAC) was measured by ultrafast spiral computed tomography, while peripheral artery calcification (PAC) was evaluated by plain x-ray of the chest, pelvis, thighs, and lower extremities.

RESULTS

The prevalence of CAC and PAC were significantly higher in the advanced CKD group compared to the early CKD group (73% vs. 38%; P < 0.01 and 85% vs. 35%; P < 0.0001, respectively). The median CAC scores were 18-fold greater in the advanced CKD group (138.9 vs. 7.8, respectively). By linear regression analysis, a strong association was found between the level of renal function and ln total volume of CAC.

CONCLUSION

Our data indicate that CAC and PAC are common and severe in HA diabetic patients with CKD not previously treated with dialysis, calcium-based phosphate binders, or vitamin D analogues. Lower level of renal function is associated with increased burden of vascular calcification in predialysis patients with CKD.

Vascular ossification-calcification in metabolic syndrome, type 2 diabetes mellitus, chronic kidney disease, and calciphylaxis-calcific uremic arteriolopathy: the emerging role of sodium thiosulfate

Background

Vascular calcification is associated with metabolic syndrome, diabetes, hypertension, atherosclerosis, chronic kidney disease, and end stage renal disease. Each of the above contributes to an accelerated and premature demise primarily due to cardiovascular disease. The above conditions are associated with multiple metabolic toxicities resulting in an increase in reactive oxygen species to the arterial vessel wall, which results in a response to injury wound healing (remodeling). The endothelium seems to be at the very center of these disease processes, acting as the first line of defense against these multiple metabolic toxicities and the first to encounter their damaging effects to the arterial vessel wall.

Results

The pathobiomolecular mechanisms of vascular calcification are presented in order to provide the clinician – researcher a database of knowledge to assist in the clinical management of these high-risk patients and examine newer therapies. Calciphylaxis is associated with medial arteriolar vascular calcification and results in ischemic subcutaneous necrosis with vulnerable skin ulcerations and high mortality. Recently, this clinical syndrome (once thought to be rare) is presenting with increasing frequency. Consequently, newer therapeutic modalities need to be explored. Intravenous sodium thiosulfate is currently used as an antidote for the treatment of cyanide poisioning and prevention of toxicities of cisplatin cancer therapies. It is used as a food and medicinal preservative and topically used as an antifungal medication.

Conclusion

A discussion of sodium thiosulfate's dual role as a potent antioxidant and chelator of calcium is presented in order to better understand its role as an emerging novel therapy for the clinical syndrome of calciphylaxis and its complications.

Breast arterial calcifications associated with diabetes and hypertension

AIM

To investigate the relationship between breast arterial calcifications (BACs) and systemic hypertension (HT) and diabetes mellitus (DM).

METHODS

Mammograms and patient records of 2406 women who were screened for breast cancer or had undergone diagnostic mammography were reviewed retrospectively. Mammograms were evaluated for the presence of arterial calcification and results were coded. Patients who had been using insulin or oral hypoglycemic agents were included in the diabetic group; patients who had been using antihypertensive agents were included in the hypertensive group. Diabetes was defined as use of oral hypoglycemic agents or insulin and hypertension was defined as use of antihypertensive agents.

RESULTS

The prevalence of BACs among diabetics (25.4) was higher than among hypertensives (17.6%). The prevalence in the nondiabetic, nonhypertensive (NDNH) group was lowest (7.3%). The prevalence increased with age. BAC was seen almost four times more in diabetic patients and three times more in hypertensive patients than in NDNH controls.

CONCLUSION

BACs are associated with diabetes and hypertension. BAC on a mammogram may indicate unsuspected diabetes or hypertension, especially after 59 years of age.

Calciphylaxis: emerging concepts in prevention, diagnosis, and treatment

Calciphylaxis is a small vessel vasculopathy involving mural calcification with intimal proliferation, fibrosis, and thrombosis. This syndrome occurs predominantly in individuals with renal failure and results in ischemia and necrosis of skin, subcutaneous fat, visceral organs, and skeletal muscle. The syndrome causes significant morbidity in the form of infection, organ failure, and pain. Mortality rates are high. In individuals with renal failure, risk factors for the development of calciphylaxis include female sex, Caucasian race, obesity, and diabetes mellitus. Many cases occur within the first year of dialysis treatment. Several recent reports demonstrate that prolonged hyperphosphatemia and/or elevated calcium x phosphorus products are associated with the syndrome. Protein malnutrition increases the likelihood of calciphylaxis, as does warfarin use and hypercoagulable states, such as protein C and/or protein S deficiency. Recent advances in diagnostic tools and therapeutic strategies have helped in the management of patients with calciphylaxis.

Peripheral artery disease, diabetes, and reduced lower extremity functioning

OBJECTIVE

To characterize lower extremity function and dysfunction in peripheral artery disease (PAD) patients with and without diabetes.

RESEARCH DESIGN AND METHODS

In this cross-sectional study, 460 men and women with PAD (147 with diabetes) were recruited from three academic medical centers. Assessments included ankle brachial index (ABI), neuropathy score, 6-min walk distance, 4-m walking velocity, Walking Impairment Questionnaire (0-100 scale, 100 = best), and summary performance score (SPS) (0-12 scale, 12 = best).

RESULTS

The mean ABI was similar in PAD patients with and without diabetes. PAD patients with diabetes were younger, had a higher BMI, had a worse neuropathy score, and had a greater number of cardiovascular comorbidities compared with those without diabetes. Participants with diabetes were less likely to report classical symptoms of intermittent claudication and more likely to report exertional leg pain, which sometimes started at rest. After adjusting for age, those with diabetes had a shorter mean 6-min walk distance (1,040 vs. 1,168 feet, P < 0.001), slower fast-pace 4-m walk velocity (0.83 vs. 0.90 m/sec, P < 0.001), and a lower SPS (7.3 vs. 8.6, P < 0.001) than those without diabetes. Patients with diet-controlled diabetes performed better than those on diabetes medications. Differences in lower extremity functioning between patients with and without diabetes were largely attenuated but not abolished for SPS and fast-pace 4-m walk velocity after adjustment for type of exertional leg pain, neuropathy score, and number of cardiovascular comorbidities.

CONCLUSIONS

Subjects with PAD and diabetes have poorer lower extremity function than those with PAD alone. This difference in functioning appears to be largely explained by diabetes-associated neuropathy, differences in exertional leg symptoms, and greater cardiovascular disease in patients with diabetes.