Clinical features of women with thrombotic microangiopathy in pregnancy: A case series from a single Japanese tertiary perinatal care center.

AIM: Although perinatal thrombotic microangiopathy has become increasingly understood, the racial characteristics of patients with this condition remain unclear. Herein, we report the characteristics of patients with perinatal thrombotic microangiopathy at a single institution in Japan. METHODS: We conducted a retrospective study over a 5-year period from January 1, 2017, to December 31, 2021, using the electronic medical records of pregnant women who delivered at the perinatal center of our hospital. We extracted the data of those who developed perinatal thrombotic microangiopathy and evaluated their characteristics at the time of disease onset, final diagnosis, and maternal and fetal outcomes. RESULTS: Of the 10 224 deliveries that occurred during the 5-year period, only seven patients (0.06%) had perinatal thrombotic microangiopathy. The median pre-pregnant body mass index was 18.65 kg/m2 (minimum 17.3 kg/m2 , maximum 20.7 kg/m2 ). More than half of the patients were conceived by in-vitro fertilization, and 42% these had twin deliveries. Four patients had a history of rheumatic disease. The other three patients without underlying diseases developed thrombotic microangiopathy with HELLP syndrome, and one patient transitioned to atypical hemolytic uremic syndrome. CONCLUSIONS: Based on low body mass index and in-vitro fertilization, which are characteristic of Japanese women, medical complications and twin pregnancies may be a risk for thrombotic microangiopathy. Additionally, depending on the cause of thrombotic microangiopathy, its timing and onset differed.

Protocol for an interventional study to reduce postpartum weight retention in obese mothers using the internet of things and a mobile application: a randomized controlled trial (SpringMom).

BACKGROUND: Obese pregnant women are known to experience poorer pregnancy outcomes and are at higher risk of postnatal arteriosclerosis. Hence, weight control during and after pregnancy is important for reducing these risks. The objective of our planned randomized controlled trial is to evaluate whether the rate of change in body weight in obese women before pregnancy to 12 months postpartum would be lower with the use of an intervention consisting of Internet of Things (IoT) devices and mobile applications during pregnancy to 1 year postpartum compared to a non-intervention group. METHODS: Women will be recruited during outpatient maternity checkups at four perinatal care institutions in Japan. We will recruit women at less than 30 weeks of gestation with a pre-pregnancy body mass index ≥ 25 kg/m2. The women will be randomly assigned to an intervention or non-intervention group. The intervention will involve using data (weight, body composition, activity, sleep) measured with IoT devices (weight and body composition monitor, activity, and sleep tracker), meal records, and photographs acquired using a mobile application to automatically generate advice, alongside the use of a mobile application to provide articles and videos related to obesity and pregnancy. The primary outcome will be the ratio of change in body weight (%) from pre-pregnancy to 12 months postpartum compared to before pregnancy. DISCUSSION: This study will examine whether behavioral changes occurring during pregnancy, a period that provides a good opportunity to reexamine one's habits, lead to lifestyle improvements during the busy postpartum period. We aim to determine whether a lifestyle intervention that is initiated during pregnancy can suppress weight gain during pregnancy and encourage weight loss after delivery. TRIAL REGISTRATION: UMIN: UMIN (University hospital Medical Information Network) 000,041,460. Resisted on 18th August 2020. https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000047278.

Lupus enteritis during pregnancy: A case-based review.

Although the symptoms of systemic lupus erythematosus (SLE) worsen during pregnancy, few previous studies have reported lupus enteritis in pregnant women with SLE. A 29-year-old pregnant Japanese woman presented with acute abdomen. Six years before pain onset, she developed pure red cell aplasia and tested positive for anti-Ro (SS-A) and anti-La (SS-B) antibodies. Anti-DNA antibodies were detected two and a half years later. The patient remained asymptomatic until she developed acute abdomen. A mild increase in anti-DNA antibody levels and a mild decrease in complement levels were observed, and abdominal ultrasound and magnetic resonance imaging revealed the presence of large-volume ascites and edematous thickening of the small intestinal wall. These findings established the diagnosis of lupus enteritis. Her condition improved after treatment with prednisolone 50 mg/day, and she delivered a female infant weighing approximately 1810 g at 37 weeks of gestation. Our study suggests that lupus enteritis should be suspected in female patients with autoimmune disease who develop acute abdomen during pregnancy, and that magnetic resonance imaging is useful in its diagnosis.

Association Between Periconceptional Diet Quality and Hypertensive Disorders of Pregnancy: The Japan Environment and Children's Study.

BACKGROUND: Little is known about the relationship of healthy diets, which are widely recommended to prevent diseases in general populations, with the risk of hypertensive disorders of pregnancy (HDP), particular among non-Western populations with different dietary habits. We aimed to investigate the association between periconceptional diet quality and the risk of HDP among pregnant Japanese women. METHODS AND RESULTS: Dietary intake over 1 year before the first trimester of pregnancy was assessed using a validated, self-administered food frequency questionnaire among 81 113 pregnant Japanese women who participated in a prospective cohort of the Japan Environment and Children's Study. Overall diet quality was assessed by the Balanced Diet Score (BDS) based on adherence to the country-specific dietary guidelines and the Dietary Approaches to Stop Hypertension (DASH) score. Cases of HDP were identified by medical record transcription. The association between diet quality and HDP risk was examined using Bayesian logistic regression models with monotonic effects. We identified 2383 (2.9%) cases of HDP. A higher BDS was associated with a lower risk of HDP. When comparing the highest with the lowest quintile of the BDS, the adjusted odds ratio (aOR) of HDP was 0.83 (95% credible interval [CrI], 0.73-0.94). The DASH score and HDP risk were inversely associated in a monotonic dose-response manner (aOR per 1-quintile increase in the DASH score, 0.92 [95% CrI, 0.89-0.95]). CONCLUSIONS: A high-quality diet, which is recommended for disease prevention in general populations, before conception may also reduce the risk of HDP among pregnant Japanese women.

The (pro)renin receptor/ATP6AP2 is essential for vacuolar H+-ATPase assembly in murine cardiomyocytes.

RATIONALE: The (pro)renin receptor [(P)RR], encoded in ATP6AP2, plays a key role in the activation of local renin-angiotensin system (RAS). A truncated form of (P)RR, termed M8.9, was also found to be associated with the vacuolar H(+)-ATPase (V-ATPase), implicating a non-RAS-related function of ATP6AP2. OBJECTIVE: We investigated the role of (P)RR/ATP6AP2 in murine cardiomyocytes. METHODS AND RESULTS: Cardiomyocyte-specific ablation of Atp6ap2 resulted in lethal heart failure; the cardiomyocytes contained RAB7- and lysosomal-associated membrane protein 2 (LAMP2)-positive multivesicular vacuoles, especially in the perinuclear regions. The myofibrils and mitochondria remained at the cell periphery. Cardiomyocyte death was accompanied by numerous autophagic vacuoles that contained undigested cellular constituents, as a result of impaired autophagic degradation. Notably, ablation of Atp6ap2 selectively suppressed expression of the V(O) subunits of V-ATPase, resulting in deacidification of the intracellular vesicles. Furthermore, the inhibition of intracellular acidification by treatment with bafilomycin A1 or chloroquine reproduced the phenotype observed for the (P)RR/ATP6AP2-deficient cardiomyocytes. CONCLUSIONS: Genetic ablation of Atp6ap2 created a loss-of-function model for V-ATPase. The gene product of ATP6AP2 is considered to act as in 2 ways: (1) as (P)RR, exerting a RAS-related function; and (2) as the V-ATPase-associated protein, exerting a non-RAS-related function that is essential for cell survival.

Prorenin receptor is essential for normal podocyte structure and function.

The prorenin receptor is an accessory subunit of the vacuolar H(+)-ATPase, suggesting that it has fundamental functions beyond activation of the local renin-angiotensin system. Podocytes express the prorenin receptor, but its function in these cells is unknown. Here, podocyte-specific, conditional, prorenin receptor-knockout mice died of kidney failure and severe proteinuria within 4 weeks of birth. The podocytes of these mice exhibited foot process effacement with reduced and altered localization of the slit-diaphragm proteins nephrin and podocin. Furthermore, the podocytes contained numerous autophagic vacuoles, confirmed by enhanced accumulation of microtubule-associated protein 1 light chain 3-positive intracellular vesicles. Ablation of the prorenin receptor selectively suppressed expression of the V(0) c-subunit of the vacuolar H(+)-ATPase in podocytes, resulting in deacidification of intracellular vesicles. In conclusion, the prorenin receptor is important for the maintenance of normal podocyte structure and function.

Optimal blood pressure target to prevent severe hypertension in pregnancy: A systematic review and meta-analysis.

Severe hypertension in pregnancy is a hypertensive crisis that requires urgent and intensive care due to its high maternal and fetal mortality. However, there is still a conflict of opinion on the recommendations of antihypertensive therapy. This study aimed to identify the optimal blood pressure (BP) levels to prevent severe hypertension in pregnant women with nonsevere hypertension. Ovid MEDLINE and the Cochrane Library were searched, and only randomized controlled trials (RCTs) were included if they compared the effects of antihypertensive drugs and placebo/no treatment or more intensive and less intensive BP-lowering treatments in nonsevere hypertensive pregnant patients. A random effects model meta-analysis was performed to estimate the pooled risk ratio (RR) for the outcomes. Forty RCTs with 6355 patients were included in the study. BP-lowering treatment significantly prevented severe hypertension (RR, 0.46; 95% CI, 0.37-0.56), preeclampsia (RR, 0.82; 95% CI, 0.69-0.98), severe preeclampsia (RR, 0.38; 95% CI, 0.17-0.84), placental abruption (RR, 0.52; 95% CI, 0.32-0.86), and preterm birth (< 37 weeks; RR, 0.81; 95% CI, 0.71-0.93), while the risk of small for gestational age infants was increased (RR, 1.25; 95% CI, 1.02-1.54). An achieved systolic blood pressure (SBP) of < 130 mmHg reduced the risk of severe hypertension to nearly one-third compared with an SBP of ≥ 140 mmHg, with a significant interaction of the BP levels achieved with BP-lowering therapy. There was no significant interaction between the subtypes of hypertensive disorders of pregnancy and BP-lowering treatment, except for placental abruption. BP-lowering treatment aimed at an SBP < 130 mmHg and accompanied by the careful monitoring of fetal growth might be recommended to prevent severe hypertension.

Trazodone Levels in Maternal Serum, Cord Blood, Breast Milk, and Neonatal Serum.

Background: Trazodone is used to treat anxiety disorder, insomnia, and sleep disorders, which occur in ∼15% of pregnant and lactating women. However, pharmacokinetic information on the transfer of trazodone and its active metabolite, 1-m-chlorophenylpiperazine (mCPP), across the placenta or into breast milk is limited. In this study, we describe the pharmacokinetic profile of trazodone and mCPP concentrations in maternal and neonatal blood and breast milk. Case Presentation: A 44-year-old female received oral trazodone 50 mg once daily during pregnancy (28-38 gestational weeks) and lactation, along with etizolam for anxiety disorder with depressive syndrome. A male infant weighing 2,918 g was born at 38 weeks of gestation. Because of persistent respiratory disturbance, oxygenation was initiated immediately after birth, and the infant was admitted in the neonatal intensive care unit for 5 days. No pulmonary dysfunction or birth defects were detected, and no medication and circulatory support were needed during admission. Trazodone and mCPP concentrations in cord blood at 7.4 hours after maternal dosing were 267.6 and 22.8 ng/mL, respectively, which were comparable with maternal serum levels. The trazodone and mCPP concentrations in breast milk collected 7.2 hours after maternal dosing were 50.2 and 3.2 ng/mL, respectively. The infant developed normally, with no drug-related adverse effects at the 1-, 3-, and 6-month postpartum checkups. Conclusion: Trazodone and its active metabolite were transferred into placenta and breast milk. However, their effects in utero could not be clarified. Further studies are warranted to assess the safety of trazodone in fetuses and breastfed infants.

Association of maternal birth weight with the risk of low birth weight and small-for-gestational-age in offspring: A prospective single-center cohort study.

BACKGROUND: Although low birth weight in Japan has slightly increased over the past several decades, the association between maternal birth weight and pregnancy outcomes remains poorly understood. METHODS: In this hospital-based, prospective cohort study conducted at the National Center for Child Health and Development, we obtained information on pregnant women's birth weight via their maternal and child health handbook. We analyzed 944 women born at term after dividing them into five categories according to their birth weight: <2500 g, 2500-2999 g, 3000-3499 g, 3500-3999 g, and ≥4000 g. Multivariate logistic regression analysis and trend analysis were used to elucidate the extent to which maternal birth weight was associated with small-for-gestational-age and low birth weight in offspring, as well as with hypertensive disorders of pregnancy. RESULTS: Compared with women with a birth weight of 3000-3499 g, those born with a birth weight <2500 g had a significantly higher risk of low birth weight (adjusted odds ratio: 5.39, 95% confidence interval: 2.06-14.1) and small-for-gestational-age (adjusted odds ratio: 9.11, 95% confidence interval: 3.14-26.4) infants. No significant association was found between the incidence of hypertensive disorders of pregnancy and preterm birth. A linear relationship was observed between the lower birth weight categories and a higher risk of low birth weight and small-for-gestational-age (p-values for trends: 0.009 and <0.001, respectively), but no linear relationship was observed for the risk of preterm birth and hypertensive disorders of pregnancy (p-value for trends: 0.317 and 0.157, respectively). CONCLUSIONS: Our findings suggest that lower maternal birth weight is associated with small-for-gestational-age and low birth weight in offspring of women born at term.

New approaches to blockade of the renin-angiotensin-aldosterone system: characteristics and usefulness of the direct renin inhibitor aliskiren.

Since renin inhibition interferes with the first and rate-limiting steps in the renin-angiotensin system, the renin step is a very attractive target for lowering blood pressure and minimizing target-organ damage. The newly developed direct renin inhibitor aliskiren has several attractive characteristics: it definitively reduces plasma renin activity among inhibitors of the renin-angiotensin system, is remarkably specific for human renin, exhibits a long half-life in plasma comparable to that of amlodipine, and has a high affinity for renal glomeruli and vasculature. Although these characteristics suggest the clinical usefulness and safety of aliskiren, several problems remain unsolved. Why does aliskiren have beneficial effects on the heart and kidneys of patients treated with angiotensin-converting enzyme (ACE) inhibitors and/or angiotensin II type 1-receptor blockers (ARBs)? Is the blood-pressure-lowering effect of aliskiren dependent on the plasma renin activity? Does aliskiren exert a possible adverse effect via (pro)renin receptor-dependent intracellular signals? Here, we review the characteristics and usefulness of aliskiren and discuss the current issues associated with this direct renin inhibitor.

Effects of telmisartan on arterial stiffness assessed by the cardio-ankle vascular index in hypertensive patients.

BACKGROUND/AIMS: This study was conducted to determine the effect of telmisartan on the cardio-ankle vascular index (CAVI), a novel blood pressure (BP)-independent marker for arterial stiffness in hypertensive patients. METHODS: One hundred consecutive hypertensive patients were randomly assigned either to a group treated with calcium channel blocker (CCB)-based therapy or a group treated with telmisartan-based therapy. Clinical and biological parameters were then measured before and 12 months after the start of this study. RESULTS: CAVI, the logarithm of urinary albumin excretion, and BP were reduced significantly after telmisartan-based therapy. The decreases in 24-hour diastolic BP and daytime systolic BP associated with telmisartan-based therapy were significantly greater than those associated with CCB-based therapy. Both therapies significantly and similarly decreased the clinical BP, 24-hour systolic BP, daytime diastolic BP and serum levels of low-density lipoprotein cholesterol. No significant differences in the metabolic parameters were observed between the two therapies. CONCLUSION: Telmisartan-based therapy had beneficial effects on arterial stiffness assessed by CAVI, albuminuria, 24-hour BP and metabolism compared with CCB-based therapy. Since these markers are known to influence the future risk of cardiovascular events, telmisartan could be a useful drug for hypertensive patients.

Renoprotective effects of mineralocorticoid receptor blockade in heminephrectomized (pro)renin receptor transgenic rats.

1. Nephropathy and elevated plasma aldosterone concentrations (PAC) have been observed in (pro)renin receptor transgenic (TG) rats. In the present study, we hypothesized that PAC and/or mineralocorticoid receptor contribute to the nephropathy of TG rats. To test this hypothesis, the effects of a high-sodium (8% NaCl) diet and heminephrectomy on PAC were examined. 2. Feeding of the high-sodium diet for 12 weeks similarly decreased PAC in TG and wild-type (WT) rats. Heminephrectomy further reduced PAC in TG rats fed a high-sodium diet, but had no effect on PAC in WT rats fed a high-sodium diet. 3. Next, the effects of eplerenone (125 mg/kg per day) and dietary salt restriction (0.36% NaCl diet) on proteinuria and renal morphology were examined in rats fed a high-sodium diet or subjected to heminephrectomy. Both eplerenone and dietary sodium restriction significantly reduced the arterial pressure of TG rats, but had no effect in WT rats. In TG rats, treatment with eplerenone significantly decreased urinary protein excretion, but dietary sodium restriction did not. 4. Nephrin and podocin mRNA levels, as determined by real-time quantitative reverse transcription-polymerase chain reaction, were significantly lower in TG rats than in WT rats. In TG rats, eplerenone treatment significantly increased nephrin mRNA levels, but not podocin mRNA levels. Dietary salt restriction significantly increased mRNA levels of both nephrin and podocin. Although zonula occludens (ZO)-1 mRNA levels were similar in both WT and TG rats, eplerenone treatment significantly decreased ZO-1 mRNA levels in TG rats. 5. The results of the present study suggest that the improvement in proteinuria following eplerenone treatment is independent of its effects on sodium balance and may be mediated by effects on the expression of slit diaphragm proteins.

Association of (pro)renin receptor mRNA expression with angiotensin-converting enzyme mRNA expression in human artery.

BACKGROUND/AIMS: A significant role of (pro)renin receptor in the pathogenesis of end-organ damage has been suggested only in animal studies. This study was conducted to examine the mRNA expression of (pro)renin receptor in human artery. METHODS: In 141 kidney failure patients, the mRNA was harvested from arterial fragments obtained during surgery constructing an arteriovenous access for hemodialysis therapy, and expression levels of (pro)renin receptor and other components of the renin-angiotensin system were determined. RESULTS: Arterial (pro)renin receptor expression was similar in diabetic and non-diabetic patients, although plasma prorenin levels were significantly higher in the diabetic patients than in the non-diabetic patients. The arterial (pro)renin receptor mRNA levels of the hypertensive patients, who had not been treated with either angiotensin-converting enzyme (ACE) inhibitors or angiotensin II type 1 receptor blockers, were significantly lower than those of the patients who had been treated with either drug. Multiple regression analyses showed a significant association with a large coefficient between the arterial mRNA level of the (pro)renin receptor and the arterial mRNA level of ACE; this significant association disappeared in patients who had been treated with either drug. CONCLUSION: (Pro)renin receptor may contribute to the generation of arterial angiotensin II in kidney failure patients.

Involvement of (pro)renin receptor in the glomerular filtration barrier.

(Pro)renin receptor-bound prorenin not only causes the generation of angiotensin II via the nonproteolytic activation of prorenin, it also activates the receptor's own intracellular signaling pathways independent of the generated angiotensin II. Within the kidneys, the (pro)renin receptor is not only present in the glomerular mesangium, it is also abundant in podocytes, which play an important role in the maintenance of the glomerular filtration barrier. Recent in vivo studies have demonstrated that the overexpression of the (pro)renin receptor to a degree similar to that observed in hypertensive rat kidneys leads to slowly progressive nephropathy with proteinuria. In addition, the handle region peptide, which acts as a decoy peptide and competitively inhibits the binding of prorenin to the receptor, is more beneficial than an angiotensin-converting enzyme inhibitor with regard to alleviating proteinuria and glomerulosclerosis in experimental animal models of diabetes and essential hypertension. Thus, the (pro)renin receptor may be upregulated in podocytes under hypertensive conditions and may contribute to the breakdown of the glomerular filtration barrier.

Renin, prorenin and the kidney: a new chapter in an old saga.

The binding of prorenin to the (pro)renin receptor triggers 2 major pathways: a nonproteolytic conformational change in prorenin to its active form (angiotensin II-dependent pathway) and an intracellular pathway via the (pro)renin receptor itself (angiotensin II-independent pathway). In diabetic animals, an increased plasma prorenin level not only causes the generation of angiotensin II via the angiotensin II-dependent pathway, it also stimulates the transliteration receptors own intracellular signaling pathway in a manner that is independent of the generated angiotensin II. Thus, the administration of a "handle" region peptide (HRP), which acts as a decoy peptide and competitively inhibits the binding of prorenin to the (pro)renin receptor, has a beneficial effect in the kidneys of diabetic animals with low plasma renin levels. However, the benefits of HRP are slightly reduced in animal models of essential hypertension with relatively high plasma renin levels, and these benefits disappear altogether in animal models of hypertension with extremely high plasma renin levels. Thus, in the kidneys of animal models of diabetes and/or hypertension, both renin and prorenin competitively bind to the (pro)renin receptor and contribute to the pathophysiology of nephropathy. Consequently, renin, prorenin and the (pro) renin receptor may be important therapeutic targets for the prevention and regression of nephropathy in patients with diabetes and/or hypertension.

Add-on benefits of amlodipine and thiazide in nondiabetic chronic kidney disease stage 1/2 patients treated with valsartan.

Hypertension frequently requires combination therapy to attain efficient control to prevent cardiovascular diseases effectively. This study was conducted to determine which add-on treatment is better, namely calcium channel blockers or diuretics, in improving vascular damage. In 70 nondiabetic chronic kidney disease stage 1/2 patients who had been already treated with angiotensin II type 1 receptor blocker valsartan for at least 12 months, amlodipine or hydrochlorothiazide was added to their existing medication. Pulse wave velocity (PWV), intima-media thickness (IMT) of the carotid arteries, urinary albumin excretion (UAE), and 24-hour ambulatory blood pressure (BP) were determined before and 12 months after the start of add-on treatments. Add-on amlodipine and add-on hydrochlorothiazide significantly and similarly decreased 24-hour ambulatory BP by 18 and 19 mm Hg, respectively, PWV by 206 and 184 cm/s, respectively, and UAE, but did not change the IMT. The decreases in BP significantly contributed to the decreases in PWV and UAE and suggested that the decrease in serum cholesterol level brought about by add-on amlodipine also contributed to the decrease in UAE. These results suggest that 12 months of add-on treatment with either amlodipine or hydrochlorothiazide could have beneficial effects in nondiabetic chronic kidney disease stage 1/2 patients already being treated with valsartan.

Safety of Amlodipine in Early Pregnancy.

Background Amlodipine is used for the treatment of hypertension, but reports on its use in early pregnancy are limited. Methods and Results In the present study, we recruited 231 women with chronic hypertension, including those who received amlodipine or other antihypertensives during early pregnancy, and investigated frequencies of morphologic abnormalities in their 231 offspring. Specifically, we evaluated 48 neonates exposed to amlodipine in the first trimester (amlodipine group, Group A), 54 neonates exposed to antihypertensives other than amlodipine (other antihypertensive group, Group O), and 129 neonates not exposed to antihypertensives (no-antihypertensive group, Group N). The number of morphologic abnormalities of offspring in each group were 2 in Group A (4.2%; 95% CI, 0.51-14.25); 3 in Group O (5.6%; 95% CI, 1.16-15.39) and 6 in Group N (4.7%; 95% CI, 1.73-9.85). The odds ratio of the primary outcome comparing Group A and Group O was 0.74 (95% CI: 0.118-4.621) and Group A and Group N was 0.89 (95% CI: 0.174-4.575). Conclusions The odds of birth defects in Group A in the first trimester were not significantly different from those with or without other antihypertensives.

Cardio-ankle vascular index and ankle pulse wave velocity as a marker of arterial fibrosis in kidney failure treated by hemodialysis.

BACKGROUND: Patients with kidney failure treated with hemodialysis have a high incidence of cardiovascular diseases caused by accelerated arteriosclerosis. However, accurate evaluation of the extent of arteriosclerosis is difficult. This study sought to compare the strength of predictions of arterial fibrosis by using a new parameter, the cardio-ankle vascular index (CAVI), versus pulse wave velocity (PWV) in patients with kidney failure treated with hemodialysis. STUDY DESIGN: Diagnostic test study. SETTING & PARTICIPANTS: 103 patients with kidney failure undergoing surgical construction of an arteriovenous access for hemodialysis therapy. INDEX TEST: CAVI and PWV. REFERENCE TEST: Arterial fibrosis, evaluated by using Masson trichrome stain on part of the brachial artery obtained during surgery, expressed as percentage of fibrosis of the layer of vascular smooth muscle cells. RESULTS: Median percentage of arterial stiffness was 52.85%. Mean PWV and CAVI were 18.3 +/- 5.6 (SD) m/s and 9.9 +/- 2.6, respectively. Multivariate regression analysis showed that arterial fibrosis was significantly associated with older age (0.247%/y; 95% confidence interval, 0.013 to 0.482) and CAVI (6.117%/unit; 95% confidence interval, 4.764 to 4.740), but not with systolic blood pressure (0.039%/mm Hg; 95% confidence interval, -0.076 to 0.153) or PWV (-0.044%/m/s; 95% confidence interval, -0.646 to 0.558). The area under the receiver operating characteristic curve to predict greater than median percentage of arterial stiffness was 0.892 for CAVI and 0.779 for PWV (P = 0.006). LIMITATION: It is unclear whether arterial fibrosis of the brachial artery evaluated by using CAVI is applicable for arteriosclerosis of other arterial districts, and clinical outcomes were not evaluated in this study. CONCLUSION: CAVI reflects the histological arterial fibrosis of hemodialysis patients and is a useful clinical marker for evaluating arterial stiffness in these patients.