Effect of Genetic Polymorphism of CYP3A5 and CYP2C19 and Concomitant Use of Voriconazole on Blood Tacrolimus Concentration in Patients Receiving Hematopoietic Stem Cell Transplantation.

BACKGROUND: Blood tacrolimus (TAC) concentration delivered via intravenous administration is known to be influenced by genetic polymorphism of CYP3A5 and interaction with triazole antifungal agents. However, interindividual variability of blood TAC concentration is as of yet still difficult to predict during the early stages of hematopoietic stem cell transplantation (HSCT). This study was conducted to assess the wide variability of blood TAC concentrations because of the hepatic metabolic activities of CYP3A and CYP2C19 in HSCT recipients. METHODS: This study is a single-institute prospective study that includes 21 adult patients who underwent HSCT and received 24 hours continuous intravenous administration of TAC at the Mie University Hospital between January 2009 and March 2014. After HSCT, the changes in blood TAC concentration/dose (C/D) ratio and TAC dose reduction from initial dose were investigated. RESULTS: Significant differences between HSCT recipients with CYP3A5*1 allele and CYP3A5*3/*3 genotype were observed with respect to the median TAC C/D ratio on day 14 (563 versus 742 ng/mL per mg/kg, P < 0.01) and day 21 (672 versus 777 ng/mL per mg/kg, P < 0.05) after HSCT. Concomitant administration of voriconazole (VRCZ), but not of lansoprazole, was found to significantly increase the median TAC C/D ratio on day 14 (557 versus 723 ng/mL per mg/kg, P < 0.01). Possession of the CYP3A5*3/*3 genotype (day 14: odds ratio, 32.2; day 21: odds ratio, 33.0; P < 0.05) and concomitant administration of VRCZ (day 14: odds ratio, 37.8; P < 0.05) were found to be independent risk factors, which significantly contributed to an increased TAC C/D ratio. In HSCT recipients with CYP3A5*3/*3 genotype (78.0%), the median TAC dose ratio (day 21/day -1) was significantly lower compared with HSCT recipients with the CYP3A5*1 allele (94.1%), whereas VRCZ administration itself had no significant influence. Interestingly, in HSCT recipients with CYP2C19*1/*1, we found that the influence of VRCZ on the TAC dose ratio (85.7%) was relatively mild, even in a recipient with CYP3A5*3/*3. CONCLUSIONS: In HSCT recipients, the variability of intravenous TAC concentration in the blood could be explained in part by the genetic variation of CYP3A5. The study results also strongly imply that the magnitude of hepatic interaction between TAC and VRCZ is affected by the genetic polymorphism of both CYP3A5 and CYP2C19 genes.

[Trends and Challenges of the Statutory Regulation of Molecular Genetic Tests].

Advances in basic science have made it possible to characterize tumors at molecular levels and exploit the differences in the genetic makeup of tumors for personalized cancer treatment. Biomarker tests are essential to stratify patients with the same tumor histology for appropriate treatment. Such tests are developed together with drugs, involving mainly molecular genetic tests at present, and are called companion diagnostics (CDx). Under the universal health care system in Japan, molecular genetic tests are permitted in clinics, and the fees are reimbursed only when approved diagnostic reagents or kits are used. However, new tests are developed so fast that the regulation cannot keep up with the pace. To fill this gap, the framework of advanced medical technologies was introduced in 1984. In 2012, this framework was amended to classify medical technology using unapproved diagnostics or home-brew assays as advanced medical technologies A. In my talk at this symposium, trends and challenges of the statutory regulation of molecular genetic tests in Japan were discussed, followed by personal proposals to advance the clinical application of novel medical technologies in the field of personalized cancer treatment.

[Issues of Personalized Medicine from the Viewpoint of Laboratory Medicine].

Personalized medicine is expected to provide patients with safe and effective treatment compared to conventional medical care in which patients are treated based on the diagnosis and/or histology. In personalized medicine, patients are treated based on their genetic makeup and genetic characteristics of tumor tissues in the case of cancer chemotherapy. Genomic biomarker tests are used to molecularly characterize host and tumor tissues and stratify patients for the appropriate drugs. Drugs targeting the causative genetic changes have been developed along with companion diagnostics to test such genetic changes. In this paper, I introduce the technical guidance for companion diagnostics and related drugs issued by the Pharmaceutical and Medical Devices Agency of Japan, and discuss how to carry out a concordance study of diagnostic tests for the ALK fusion gene when new ALK inhibitors are approved. The regulations for companion diagnostics should be revised frequently to keep up with advances in this area.

Resveratrol sensitizes HepG2 cells to TRAIL-induced apoptosis.

Resveratrol is a natural polyphenol found in a wide variety of plants, including grapes, berries, and peanuts. Resveratrol can modulate a wide spectrum of molecular targets, including those involved in cancer signaling pathways. Here, we evaluated the role of resveratrol in tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and examined the molecular mechanisms in the human hepatocellular carcinoma cell line HepG2. We used the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay to assess cell viability, flow cytometry to analyze cell cycle and apoptosis, and immunoblotting to detect protein expression. Resveratrol decreased cell viability at a concentration of 100 µmol/l or higher. At a concentration of 50 µmol/l, resveratrol induced S phase arrest of the cell cycle without apoptosis. In addition, phospho-AMPK increased significantly in a dose-dependent manner. Resveratrol was found to synergistically augment TRAIL-induced apoptosis. The rates of early apoptosis were 3.4, 9.6, and 49.6% on treatment with 50 µmol/l resveratrol, 10 ng/ml TRAIL, and both reagents, respectively. Resveratrol significantly downregulated the expression of survivin in a dose-dependent manner. In conclusion, we found that that resveratrol could augment TRAIL sensitivity by downregulating survivin. These results suggest that combination resveratrol with TRAIL may be an effective new strategy for the treatment of hepatocellular carcinoma.

[Discussing the usefulness of companion diagnostics - introductory remarks by chairpersons].

Personalized medicine has been expected to be utilized in daily practice since the international human genome project completed sequencing of the entire genome in 2003. The aim of personalized medicine is to treat patients effectively and safely based on the genome characteristics of each patient, or to choose the right drug for the right patient at the right time and at the right dose. Regulatory agencies such as the United States Food and Drug Administration(FDA) and Pharmaceuticals and Medical Devices Agency (PMDA), Japan implemented guidance to facilitate the co-development of drugs and companion diagnostics. For the practice of personalized medicine, companion diagnostic tests are essential, although their availability is limited.

[Development of Rapid Assay of Transthyretin in Whole Blood].

Transthyretin (TTR), a rapid turnover protein with a half-life of 2 days, which is shorter than that of albumin, is considered to be a sensitive indicator of a patient's nutritional status. We have newly developed a rapid assay of TTR by immunochromatography (IC) using samples of whole blood as well as serum at volumes of 10 µL. The fundamental performance was evaluated using control sera. In addition, whole blood samples were measured by IC and the results were compared with measured levels of plasma samples by turbidimetry and those of sera by nephelometry. The limit of quantification was 8.3 mg/dL. The linearity was 8.7-35.4 mg/dL. The reproducibility was 6.1-8.6% coefficient of variation. Bilirubin, hemolysis, chyle, and rheumatoid factor did not influence the measured levels. An increase of 1% in hematocrit resulted in a decrease of 1% in the measured levels. The correlation between IC (y) and nephelometry (x) was determined to be y = 0.927x+2.62 (r = 0.935, n = 64). The newly developed IC showed good performance and it was suggested that IC would be useful for nutrition monitoring as point of care test.

Evaluation of clinical performance of the major BCR-ABL mRNA detection kit which enables conversion to international standard scale using the reference material calibrator.

In a multicenter study, we evaluated the Major BCR-ABL mRNA/ABL mRNA quantification kit (M135R), which uses reference material included in the kit designed to report results using the international scale (IS). In total, 127 samples were studied. A good correlation was observed between M135R results and home-brew RT-qPCR results, which are reported on the IS using a conversion factor (r=0.90; n=115). However, the correlation coefficient between M135R results and Amp-CML results was relatively low (r=0.56; n=108). A good correlation was observed between M135R results from the two assay sites (r=0.94; n=115). The subset analysis of samples from the two assay sites showed M135R to have a good correlation even in the low IS range (r=0.98; IS≤1%). M135R showed high sensitivity and accuracy for detecting minimal residual disease and is considered to be a useful tool for treatment response assessment and for early detection of recurrence in CML patients.

Des-γ-carboxy prothrombin ratio measured by P-11 and P-16 antibodies is a novel biomarker for hepatocellular carcinoma.

Serum tumor markers, including α-fetoprotein (AFP) and des-γ-carboxy prothrombin (DCP), are currently used in the diagnosis of hepatocellular carcinoma (HCC). There is, however, an aberrant increase in serum DCP in patients with obstructive jaundice, vitamin K deficiency or who are taking warfarin, resulting from a problem with the current methodology for measurement of this marker. This study aimed to elucidate the utility of a new biomarker, NX-PVKA, for early diagnosis of HCC. A total of 96 patients were included in the HCC group. The control group included 138 liver cirrhosis (LC) patients without HCC. Serum concentrations of conventional DCP, AFP, AFP-L3 and NX-PVKA were measured. The NX-PVKA ratio was calculated by dividing DCP by NX-PVKA. In patients not taking warfarin, the area under the curve values of DCP, NX-PVKA ratio, AFP and AFP-L3 were 0.715, 0.690, 0.737 and 0.654, respectively, confirming the clinical utility of these markers in detecting HCC. In cases with DCP > 35 mAU/mL in particular, a significant increase in the NX-PVKA ratio was observed in patients with HCC. In those cases, the cut-off value for the NX-PVKA ratio that was optimized by the receiver operating characteristic (ROC) curve was 1.15. In addition, the sensitivity and specificity for diagnosing HCC were 69.2% and 75.9%, respectively. Patients with HCC had higher NX-PVKA ratios compared to patients with LC taking warfarin (P = 0.063). These results suggest that, when used in combination with DCP, the NX-PVKA ratio is a promising novel marker for the detection of HCC.

Differential activation of eosinophils by bacteria associated with asthma.

BACKGROUND: It has been suggested that there is a complex interaction between microbiota and various human diseases. Some bacteria have been reported to be involved in the inception and progression of asthma, and others in the protection against asthma. We know very little about the mechanisms by which bacteria do harm or good with regard to asthma. This study investigated whether bacteria exert differential effects on the functions of eosinophils, major effector cells in airway inflammation in asthma. METHODS: Eosinophils were purified from healthy adult volunteers by Percoll density gradient centrifugation and negative immunomagnetic bead selection using anti-CD16 microbeads. Three kinds of heat-killed bacteria that have been implicated in asthma, namely Staphylococcus aureus (SA), Haemophilus influenzae (HI) and a Prevotella sp. (PS), were tested for their effects on the secretion of eosinophil-derived neurotoxin (EDN), the generation of superoxides and the production of cytokines/chemokines. RESULTS: SA, but not HI or PS, induced significant EDN release in a dose-dependent manner. Superoxide generation was significantly enhanced by each of the bacterial species, but most strongly by SA, which induced significantly greater TNF-α production by eosinophils than either HI or PS. Conversely, interleukin 10, an anti-inflammatory cytokine, was more strongly induced by HI and PS than by SA. CONCLUSIONS: Bacteria exert differential effects on eosinophils. Based on these results, SA may be involved in the exacerbation of, and HI and PS in the inhibition of, eosinophilic inflammation in asthma.

Clinical utility of a panfungal polymerase chain reaction assay for invasive fungal diseases in patients with haematologic disorders.

OBJECTIVES: Invasive fungal diseases (IFDs) are life-threatening events in patients with haematologic disorders, and the spectrum of the aetiological pathogens continues to expand. This study aimed to evaluate the clinical utility of a panfungal polymerase chain reaction (PCR) assay for the management of IFDs in such patients. METHODS: We prospectively analysed 273 consecutive blood samples from 64 risk episodes in 51 patients with haematologic disorders at high risk for IFD who were treated at our hospital between April 2007 and October 2010. RESULTS: PCR-positive results were obtained in 18 of 64 risk episodes (35.3%). IFD was documented in 14 episodes (21.9%, 9 probable IFDs and 5 possible IFDs) according to the revised criteria of the European Organization for Research and Treatment of Cancer/Mycoses Study Group. PCR was positive in all of these 14 episodes, and in 4 of the 50 episodes with no IFD category. Sensitivity, specificity, positive predictive value, and negative predictive value of our assay were 100%, 92%, 78% and 100% respectively. A considerable number of fungi (44.4%) that are less common than Aspergillus and Candida species were positive by PCR. Molecular diagnoses of Cunninghamella species, Aspergillus ustus, Fusarium species, Scedosporium apiospermum, Rhodotorula species and Rhizopus species were beneficial in selecting suitable treatments. CONCLUSIONS: Our panfungal PCR approach allows for the highly sensitive and specific detection and identification of a wide spectrum of fungal pathogens, which provides indispensable information for managing IFDs, especially refractory or breakthrough IFDs during antifungal therapy in high-risk patients with haematologic disorders.

Immune response following liver transplantation compared to kidney transplantation: usefulness of monitoring peripheral blood CD4+ adenosine triphosphate activity and cytochrome P450 3A5 genotype assay.

Seventy living donor liver transplantation (LDLT) and 39 kidney transplantation (KT) patients were randomly screened by using the peripheral blood CD4+ adenosine triphosphate activity (ATP) assay (IMK assay). The patients were divided into 2 groups in each organ transplantation with low IMK ATP level (<225 ng/mL) or high (>225) (LT-L: n = 23, KT-L: n = 19, LT-H: n = 47, and KT-H: n = 20, resp.). The incidence of bacterial and/or viral infection was significantly higher in LT-L group than in LT-H group (74.0 versus 8.5%: P < 0.001). Occurrence of total viral infection in KT-L was also significantly higher than that in KT-H (36.8 versus 10%: P = 0.046). The sensitivity and specificity of the IMK assay for identifying risk of infection was 0.810 and 0.878 in LDLT patients and 0.727 and 0.607 in KT patients. The percentage of LDLT patients with cytochrome P450 3A5 (CYP3A5) *1/*1 or *1/*3 genotype (expressors) was significantly higher in LT-L group than in LT-H group (53.8 versus 20.7%: P = 0.032). In both LDLT and KT patients, the IMK assay can be useful for monitoring immunological aspects of bacterial and/or viral infection. CYP3A5 expressors in LT-L group are related to postoperative infections.

Immunological aspects in late phase of living donor liver transplant patients: usefulness of monitoring peripheral blood CD4+ adenosine triphosphate activity.

AIM: To evaluate whether the combination of the peripheral blood CD4+ adenosine triphosphate activity (ATP) assay (ImmuKnow assay: IMK assay) and cytochrome P450 3A5 (CYP3A5) genotype assay is useful for monitoring of immunological aspects in the patient followup of more than one year after living donor liver transplantation (LDLT). METHODS: Forty-nine patients, who underwent LDLT more than one year ago, were randomly screened by using IMK assay from January 2010 to December 2011, and the complete medical records of each patient were obtained. The CYP3A5 genotypes were examined in thirty-nine patients of them. RESULTS: The mean ATP level of the IMK assay was significantly lower in the patients with infection including recurrence of hepatitis C (HCV) (n = 10) than in those without infection (n = 39): 185 versus 350 ng/mL (P < 0.001), while it was significantly higher in the patients with rejection (n = 4) than in those without rejection (n = 45): 663 versus 306 ng/mL (P < 0.001). The IMK assay showed favorable sensitivity/specificity for infection (0.909/0.842) as well as acute rejection (1.0/0.911). CYP3A5 genotypes in both recipient and donor did not affect incidence of infectious complications. CONCLUSIONS: In the late phase of LDLT patients, the IMK assay is very useful for monitoring immunological aspects including bacterial infection, recurrence of HCV, and rejection.

Quantifying longitudinal right ventricular dysfunction in patients with old myocardial infarction by using speckle-tracking strain echocardiography.

BACKGROUND: We investigated longitudinal right ventricular (RV) function assessed using speckle-tracking strain echocardiography in patient with myocardial infarction (MI), and identified the contributing factors for RV dysfunction. METHODS: We retrospectively studied 71 patients with old MI (the OMI group) and 45 normal subjects (the Control group) who underwent a transthoracic echocardiography. Global and free wall RV peak systolic strains (PSSs) in the longitudinal direction were measured by using speckle-tracking strain echocardiography. Left ventricular (LV) PSSs were measured in the longitudinal, radial and circumferential directions. Cardiac hemodynamics including peak systolic pulmonary artery pressure was also assessed non-invasively. Plasma brain natriuretic peptide (BNP) levels were measured in all patients. RESULTS: In the OMI group, 73% of the patients had a normal estimated peak systolic pulmonary artery pressure of less than 35 mmHg. Global and free wall RV PSS were impaired in the OMI group compared with the Control group, and these RV systolic indices were significantly associated with heart rate, logarithmic transformed plasma BNP, greater than 1 year after onset of MI, Doppler-derived estimated pulmonary vascular resistance, LV systolic indices, LV mass index, infarcted segments within a territory of the left circumflex artery and residual total occlusion in the culprit right coronary artery. Multivariable linear regression analysis indicated that reduced longitudinal LV PSS in the 4-chamber view and BNP levels ≥500 pg/ml were independently associated with reduced global and free wall RV PSS. Moreover, when patients were divided into 3 groups according to plasma BNP levels (BNP <100 pg/ml; n = 31, 100 ≤BNP <500 pg/ml; n = 24, and BNP ≥500 pg/ml; n = 16), only patients with BNP ≥500 pg/ml had a strong correlation between RV PSS and longitudinal LV PSS in the 4-chamber view (r = 0.78 for global RV PSS and r = 0.71 for free wall RV PSS, p <0.05). CONCLUSION: Longitudinal RV systolic strain depends significantly on longitudinal LV systolic strain especially in patients with high plasma BNP levels, but not on estimated peak systolic pulmonary artery pressure. These results indicate that process of RV myocardial dysfunction following MI may be governed by neurohormonal activation which causing ventricular remodeling rather than increased RV afterload.

[Potential and perspective of genetic testing in Renaissance of laboratory medicine].

Among molecular genetic tests, tests for genomic biomarkers are increasingly performed in order to decide the right drug for the right patient at the right time. These genetic tests, including pharmacogenomics (PGx) tests, are essential for personalized medicine. Companion diagnostics (CDx) will be co-developed from the early stage of drug development and used for patient stratification in Phases II/III of clinical trials. The strategic change in development from blockbuster drugs to molecularly targeted drugs will enhance the clinical application of genetic tests, including CDx and PGx. The genetic tests utilized for making treatment decisions have the potential to regenerate laboratory medicine.

[Introductory remarks by chairpersons].

Personalized medicine (PM) is expected to change the healthcare system due to great progress in areas such as pharmacogenomics (PGx) and molecular diagnostics; however, PM is more popular in oncology than in clinic practice. Oncological therapies are easily personalized because accurate diagnostic tests are available to identify patients who can benefit from targeted therapies. Nevertheless, personalized medicine has become a more imminent reality for several reasons, such as the increased awareness of drugs with an adequate benefit/risk ratio to patients, better methods to optimize drug selection and dosing and so on. We invited four speakers to discuss the importance of PGx in the practice of PM from the viewpoint of basic and clinical research.

[Pharmacogenomics].

Personalized medicine based on pharmacogenomics is being developed at the clinical stage. Pharmacogenomics involve the study of the role of genomic variation in individual variations in drug response, a phenotype that varies from potentially life-threatening adverse drug reactions to an equally serious lack of therapeutic efficacy. These developments in pharmacogenomics are strongly supported by marked innovations in genetic analyses. The molecular targets of clinical pharmacogenomics are the genetic and genomic factors of both the patient and the pathological organ. Molecular target drugs have become standard treatments in cancer therapy. The efficacy of these drugs can be predicted by characterization of the molecular target before administration. Such characterization for treatment guidance is called companion diagnostics. Companion diagnostics are tests that are intended to assist physicians in making treatment decisions for their patients based on the best response to therapy. Moreover, companion diagnostic co-development can highly change the drug development process and clinical trials by significantly yielding safer drugs with better therapeutic efficacy in a faster, more cost-effective way. However, many companies are interested in the development of companion diagnostics for targeted therapies in specific fields such as cancer. Thus, there are currently no potential companion diagnostics for common diseases. As common diseases are multifactorial, multiplex testing is required to predict therapeutic efficacy. The development of multiplex companion diagnostics is anticipated for the expansion of personalized medicine.

Donor age affects liver regeneration during early period in the graft liver and late period in the remnant liver after living donor liver transplantation.

BACKGROUND: The aim of the present study was to evaluate the influence of donor age on liver regeneration and surgical outcomes in recipients and donors. PATIENTS AND METHODS: Among 101 cases of adult-to-adult living donor liver transplantation (LDLT) between March 2002 and March 2011, according to donor age: younger (Y) <50 years of age or older (O) ≥ 50 years of age, the donors and recipients using right (R) or left (L) graft were divided into groups Y/R (n = 51) and O/R (n = 17), and groups Y/L (n = 26) and O/L (n = 7), respectively. Remnant liver volume (RemLV) and graft liver volume (GLV) were estimated by computed tomography (CT) volumetry. A disintegrin and metalloprotease with thrombospondin type I domain 13 (ADAMTS13) activities and von Willebrand factor (vWF) antigen levels were measured as factors reflecting thrombotic microangiopathy. RESULTS: Among the donors, RemLV/total liver volume (TLV) was lower in group O/R than in group Y/R, although there were no significant differences by t-test with the Bonferroni correction (rough p value = 0.02 at 6 months and rough p value > 0.05 at 1, 3, and 12 months). Donor age (≥ 50 years) was independently correlated with impaired remnant liver regeneration at 6 months in right lobe LDLT (p = 0.04). Among the recipients, GLV/standard liver volume (SLV) was lower during the first month, although there were no significant differences between the two groups by t-test with the Bonferroni correction (rough p value = 0.03 at 1 week and rough p value >0.05 at 2 weeks and 1 and 3 months). Donor age (≥ 50 years) was independently correlated with impaired graft liver regeneration at 1 week in both right and left lobe LDLT (p < 0.05). ADAMTS13 activities were lower in group O/R than in group Y/R, although there were no significant differences by t-test with the Bonferroni correction (rough p value = 0.049 on postoperative days (POD) 1 and 28 and rough p value >0.05 on POD 7 and 14). vWF/ADAMTW13 ratios were higher on POD 14, although there were no significant differences between the two groups by t-test with the Bonferroni correction (rough p value = 0.044 on POD 14 and rough p value >0.05 on POD 1, 7, 14, and 28). CONCLUSIONS: The surgical outcomes using older donor livers for LDLT were comparable to those using younger donor livers. When using older donor livers, however, we should pay attention to the liver volume for recipients as well as donors, because older donor livers might have impaired regenerative ability.

Role of haemodialytic therapy on left ventricular mechanical dyssynchrony in patients with end-stage renal disease quantified by speckle-tracking strain imaging.

BACKGROUND: Abnormal myocardial loading can contribute to left ventricular (LV) mechanical dyssynchrony in patients with end-stage renal disease (ESRD). The aims of this study were to characterize and quantify LV function and mechanical dyssynchrony in patients with ESRD, and to elucidate the impact of haemodialytic (HD) therapy on these parameters by speckle-tracking strain imaging. METHODS: Twenty-three patients with ESRD (63 ± 11 years) before (pre-dialysis group) and after HD therapy (post-dialysis group) and 28 normal subjects (control group; 60 ± 10 years) were examined by echocardiography. Global and segmental LV peak systolic strain (PSS) were analysed, and LV mechanical dyssynchrony was assessed by calculating the standard deviation of the segmental time-to-PSS over longitudinal, circumferential or radial regions, respectively. RESULTS: Global PSS and LV ejection fraction in the pre-dialysis group were similar to those in the control group, and were not altered by HD therapy. LV mechanical dyssynchronies in the longitudinal and radial directions, but not in the circumferential direction, were significantly greater in the pre-dialysis group than those in the control group [longitudinal direction: 63 ± 15 (P < 0.05 vs. the control group) vs. 49 ± 15 ms, circumferential direction: 44 ± 24 vs. 41 ± 23 ms, and radial direction: 47 ± 29 (P < 0.05 vs. the control group) vs. 16 ± 18 ms]. HD therapy dramatically improved only the radial LV dyssynchrony in the post-dialysis group (23 ± 24 ms, P < 0.05 vs. the pre-dialysis group). CONCLUSIONS: The presence of ESRD was associated with longitudinal and radial LV dyssynchronies. In addition, HD therapy dramatically improved radial LV dyssynchrony, which strongly indicates that only radial LV dyssynchrony is preload dependent among the three LV systolic directions.

Impact of chronic kidney disease on the presence and severity of aortic stenosis in patients at high risk for coronary artery disease.

OBJECTIVE: We evaluated the impact of chronic kidney disease (CKD) on the presence and severity of aortic stenosis (AS) in patients at high risk for coronary artery disease (CAD). METHODS: One hundred and twenty consecutive patients who underwent invasive coronary angiography were enrolled. Aortic valve area (AVA) was calculated by the continuity equation using transthoracic echocardiography, and was normalized by body surface area (AVA index). RESULTS: Among all 120 patients, 78% had CAD, 55% had CKD (stage 3: 81%; stage 4: 19%), and 34% had AS (AVA < 2.0 cm²). Patients with AS were older, more often female, and had a higher frequency of CKD than those without AS, but the prevalence of CAD and most other coexisting conventional risk factors was similar between patients with and without AS. Multivariate linear regression analysis indicated that only CKD and CAD were independent determinants of AVA index with standardized coefficients of -0.37 and -0.28, respectively. When patients were divided into 3 groups (group 1: absence of CKD and CAD, n = 16; group 2: presence of either CKD or CAD, n = 51; and group 3: presence of both CKD and CAD, n = 53), group 3 had the smallest AVA index (1.19 ± 0.30*# cm²/m², *p < 0.05 vs. group 1: 1.65 ± 0.32 cm²/m², and #p < 0.05 vs. group 2: 1.43 ± 0.29* cm²/m²) and the highest peak velocity across the aortic valve (1.53 ± 0.41*# m/sec; *p < 0.05 vs. group 1: 1.28 ± 0.29 m/sec, and #p < 0.05 vs. group 2: 1.35 ± 0.27 m/sec). CONCLUSION: CKD, even pre-stage 5 CKD, has a more powerful impact on the presence and severity of AS than other conventional risk factors for atherosclerosis in patients at high risk for CAD.