Modification of the CKD epidemiology collaboration (CKD-EPI) equation for Japanese: accuracy and use for population estimates

Urinary N-terminal pro-B-type natriuretic peptide as a biomarker for cardiovascular events in a general Japanese population: the Hisayama Study

BACKGROUND

Epidemiological evidence has shown that serum N-terminal pro-brain natriuretic peptide (NT-proBNP) concentrations, a diagnostic biomarker for heart failure, are positively associated with cardiovascular risk. Since NT-proBNP in serum is excreted in urine, it is hypothesized that urinary NT-proBNP concentrations are correlated with serum concentrations and linked with cardiovascular risk in the general population.

METHODS

A total of 3060 community-dwelling residents aged ≥ 40 years without history of cardiovascular disease (CVD) were followed up for a median of 8.3 years (2007-2015). Serum and urinary concentrations of NT-proBNP at baseline were compared. The hazard ratios (HRs) and their 95% confidence intervals (CIs) for the association between NT-proBNP concentrations and the risk of developing CVD were computed using the Cox proportional hazards model.

RESULTS

The median values (interquartile ranges) of serum and urinary NT-proBNP concentrations at baseline were 56 (32-104) pg/mL and 20 (18-25) pg/mL, respectively. There was a strong quadratic correlation between the serum and urinary concentrations of NT-proBNP (coefficient of determination [R²] = 0.72): urinary concentrations of 20, 27, and 43 pg/mL were equivalent to serum concentrations of 55, 125, and 300 pg/mL, respectively. During the follow-up period, 170 subjects developed CVD. The age- and sex-adjusted risk of CVD increased significantly with higher urinary NT-proBNP levels (P for trend < 0.001). This association remained significant after adjustment for traditional cardiovascular risk factors (P for trend = 0.009). The multivariable-adjusted risk of developing CVD almost doubled in subjects with urinary NT-proBNP of ≥ 43 pg/mL as compared to those with urinary NT-proBNP of ≤ 19 pg/mL (HR 2.07, 95% CI 1.20-3.56).

CONCLUSIONS

The present study demonstrated that urinary NT-proBNP concentrations were well-correlated with serum concentrations and were positively associated with cardiovascular risk. Given that urine sampling is noninvasive and does not require specially trained personnel, urinary NT-proBNP concentrations have the potential to be an easy and useful biomarker for detecting people at higher cardiovascular risk.

Lifetime risk of stroke stratified by chronic kidney disease and hypertension in the general Asian population: the Ohasama study

Lifetime risk (LTR) evaluates the absolute risk of developing a disease during the remainder of one's life. It can be a useful tool, enabling the general public to easily understand their risk of stroke. No study has been performed to determine the LTR of cardiovascular disease in patients with chronic kidney disease (CKD) with or without hypertension; therefore, we performed this study in an Asian population. We followed 1525 participants (66.0% women; age 63.1 years) in the general population of Ohasama, Japan. We defined CKD as an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m² and/or proteinuria. Hypertension was defined as a systolic/diastolic blood pressure ≥140/≥90 mmHg and/or the use of antihypertensive medication. We calculated the sex-specific LTR of stroke adjusted for the competing risk of death. During the mean follow-up period of 16.5 years, a first stroke occurred in 238 participants. The 10-year risk of stroke at the age of 45 years was 0.0% for men and women. The LTRs of stroke at the index age of 45 years (men/women) were 20.9%/14.5% for participants without CKD and hypertension, 34.1%/29.8% for those with CKD but not hypertension, 37.9%/27.3% for those with hypertension but not CKD, and 38.4%/36.4% for those with CKD and hypertension. The LTRs of stroke tended to be higher in younger participants than in older participants with CKD and/or hypertension. CKD contributed to the LTR of stroke, as did hypertension. The prevention of CKD and hypertension can reduce the LTR of stroke, especially in young populations.

High Serum Folate Concentrations Are Associated with Decreased Risk of Mortality among Japanese Adults

BACKGROUND

Folate and vitamin B-12 are essential nutrients for normal cell growth and replication, but the association of serum folate and vitamin B-12 concentrations with mortality risk remains uncertain.

OBJECTIVE

This study was performed to investigate the associations of serum folate and vitamin B-12 concentrations with mortality risk and test whether the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism modifies these associations.

METHODS

A total of 3050 Japanese community residents aged ≥40 y were prospectively followed-up for mortality between 2002 and 2012. Cox proportional hazards models and restricted cubic splines were used to estimate HRs and 95% CIs of mortality.

RESULTS

During a median follow-up period of 10.2 y, 336 participants died. Higher serum folate concentrations were associated with lower risks of all-cause mortality [multivariable-adjusted HR: 0.73; 95% CI: 0.56, 0.96 for the second tertile (8.8-12.2 nmol/L; median 10.4 nmol/L) and HR: 0.61; 95% CI: 0.46, 0.80 for the third tertile (≥12.5 nmol/L; median 15.6 nmol/L) serum folate concentrations compared with the first tertile (≤8.6 nmol/L; median 7.0 nmol/L)]. This association remained significant in all sensitivity analyses. Spline analyses showed a steady decline in all-cause mortality risk with increasing serum folate concentrations up to 20-25 nmol/L. This association persisted regardless of the MTHFR C677T genotypes. For serum vitamin B-12, the multivariable-adjusted HR of 1.32 (95% CI: 0.97, 1.79) of all-cause mortality was marginally significantly greater in the first tertile compared with the second tertile. This association was attenuated and nonsignificant after the exclusion of participants with a history of cardiovascular disease or cancer, or participants aged ≥85 y at baseline, or deaths in the first 3 y of follow-up.

CONCLUSIONS

Serum folate concentrations were inversely associated with the risk of all-cause mortality in Japanese adults. Serum vitamin B-12 concentrations were not consistently associated with all-cause mortality risk after accounting for reverse-causation bias.

Relationship of hemoglobin level and plasma coproporphyrin-I concentrations as an endogenous probe for phenotyping OATP1B

Plasma coproporphyrin‐I (CP‐I) concentration is used as a sensitive and selective endogenous probe for phenotyping organic anion transporting polypeptides 1B (OATP1B) activity in many studies. CP‐I is produced in the process of heme synthesis, but the relationship between plasma CP‐I concentrations and heme synthesis activity is unknown. In this study, we evaluated the relationship between plasma CP‐I concentration and hemoglobin level as a biomarker of heme synthesis activity. The data of 391 subjects selected from the Japanese general population were analyzed. One hundred twenty‐six participants had OATP1B1*15 allele, 11 of whom were homozygous (OATP1B1*15/*15). Multiple regression analysis identified hemoglobin level as an independent variable associated with plasma CP‐I concentration (p < 0.0001). A significant positive correlation was observed between hemoglobin level and plasma CP‐I concentration in participants without OATP1B1*15 allele (n = 265; r_s = 0.35, p < 0.0001) and with OATP1B1*15 allele (n = 126; r_s =0.27, p = 0.0022). However, Kruskal–Wallis test showed no large difference in Kruskal–Wallis statistics between the distribution of plasma CP‐I concentrations and that of ratio of plasma CP‐I to hemoglobin among six OATP1B1 polymorphism groups. These findings suggest that the hemoglobin level seems to reflect biosynthesis of CP‐I. However, correction by hemoglobin level is not required when using basal plasma CP‐I concentration for phenotyping OATP1B activity.

Consequences of exposure to prenatal famine on estimated glomerular filtration rate and risk of chronic kidney disease among survivors of the great Ethiopian famine (1983-85): a historical cohort study

BACKGROUND

The impact of an adverse prenatal environment such as famine exposure on the development of adulthood non-communicable chronic illnesses, including diabetes and hypertension has been well articulated in the recent past and supported by evidence. However, there exist few longitudinal studies conducted on the long term consequences of prenatal famine exposure on adulthood kidney function. Hence, we set out to examine whether prenatal exposure to the Ethiopian Great Famine (1983-1985) was associated with changes in estimated glomerular filtration rate (eGFR) and the risk of developing chronic kidney disease (CKD) later in adult life.

METHODS

The study was conducted in 219 famine exposed and 222 non exposed cohorts in Raya Kobo district, North Wollo Zone, Northern Ethiopia. Estimated GFR was computed from standardized serum creatinine using the CKD Epidemiology Collaboration (CKD-EPI) equation. The definition of CKD includes those with an eGFR of less than 60 ml/min/1.73 m2 on at least in two occasions of 90 days apart (with or without markers of kidney damage). Linear and logistic regression analyses were employed to examine the independent effect of prenatal famine exposure on eGFR and CKD respectively.

RESULTS

The mean (SD) serum creatinine of exposed and non-exposed groups were 0.78 (0.2) and 0.75 (0.2) respectively. The mean (SD) eGFR of exposed groups was 107.95 (27.49) while the non-exposed 114.48 (24.81) ml/min. In linear regression, the unadjusted model to examine the association between famine exposure and eGFR resulted in a significant negative beta coefficient (β = - 0.124: 95% CI: - 11.43, - 1.64). Adjusting the exposure for outstanding covariates of kidney health, including systolic blood pressure, fasting blood sugar and blood glucose did not alter the inverse relationship (β = -.114 95% CI: - 10.84, - 1.17). In the unadjusted bivariate logistic regression model, famine exposure resulted in nearly 2.7 times higher odds of developing CKD (OR: 2.68, 95% CI: 1.16, 6.2). The odds remained equivalent after adjusting for systolic blood pressure, fasting blood glucose and body mass index (OR = 2.61: 95% CI: 1.120, 6.09).

CONCLUSION

In the study setting, prenatal exposure to the Great Ethiopian Famine was associated with decreased eGFR and higher risk of developing CKD among survivors. These findings may imply that famine in early life may play a significant role in the development of kidney dysfunction in adulthood.

Retrospective Analysis of the Renoprotective Effects of Long-Term Use of Six Types of Sodium-Glucose Cotransporter 2 Inhibitors in Japanese Patients with Type 2 Diabetes Mellitus and Chronic Kidney Disease

Aim: Sodium-glucose cotransporter 2 inhibitors (SGLT2is) provide renal protection in patients with type 2 diabetes mellitus (T2DM). The aim of this study was to elucidate the renal effects of long-term use of six types of SGLT2is in Japanese patients with T2DM and chronic kidney disease (CKD). Materials and Methods: The Kanagawa Physicians Association maintains a registry of patients who visit their 31 clinics. We retrieved clinical data of patients with T2DM and CKD who were prescribed with SGLT2is for >1 year. Results: A total of 763 patients with a median treatment duration of 33 months were included. The logarithmic value of urine albumin-creatinine ratio (LNACR) decreased significantly from 1.60 ± 0.65 to 1.51 ± 0.67. The multiple linear regression analysis revealed that the LNACR at the initiation of treatment, change in (Δ) diastolic blood pressure, and Δ hemoglobin A1c were independently correlated with ΔLNACR (P < 0.001). The decrease in the LNACR was significantly smaller in the patients with estimated glomerular filtration rate (eGFR) [mL/(min ·1.73 m²)] of <60 (P < 0.05). The eGFR decreased from 77.4 ± 22.3 to 72.7 ± 22.5 mL/(min ·1.73 m²) (P < 0.001). The multiple linear regression analysis showed that the LNACR at the initiation of treatment, Δbody weight at the previous survey, ΔeGFR at the previous survey, and the eGFR at the initiation of treatment correlated independently with ΔeGFR during the maintenance period (P < 0.001). Greater changes in the eGFR during the maintenance period were observed in the patients with macroalbuminuria or eGFR of <60 (P < 0.01). Conclusions: The study confirmed that the long-term use of six types of SGLT2i improved the albumin-creatinine ratio (ACR), although the eGFR gradually decreased during the treatment. The change in the ACR was significantly smaller in the patients with eGFR of <60 mL/(min ·1.73 m²) than in those with eGFR of >60 mL/(min ·1.73 m²). However, this was a retrospective observational study; further studies are needed to formulate final conclusions.

Preservation of kidney function irrelevant of total kidney volume growth rate with tolvaptan treatment in patients with autosomal dominant polycystic kidney disease

Background

Tolvaptan slowed the rates of total kidney volume (TKV) growth and renal function decline over a 3-year period in patients with autosomal dominant polycystic kidney disease (ADPKD) enrolled in the Tolvaptan Efficacy and Safety in Management of Autosomal Dominant Polycystic Kidney Disease and Its Outcomes (TEMPO) 3:4 trial (NCT00428948). In this post hoc analysis of Japanese patients from TEMPO 3:4, we evaluated whether the effects of tolvaptan on TKV and on renal function are interrelated.

Methods

One hundred and forty-seven Japanese patients from TEMPO 3:4 were included in this analysis (placebo, n = 55; tolvaptan, n = 92). Tolvaptan-treated patients were stratified into the responder group (n = 37), defined as tolvaptan-treated patients with a net decrease in TKV from baseline to year 3, and the non-responder group (n = 55), defined as tolvaptan-treated patients with a net increase in TKV.

Results

Mean changes during follow-up in the placebo, responder, and non-responder groups were 16.99%, − 8.33%, and 13.95%, respectively, for TKV and − 12.61, − 8.47, and − 8.58 mL/min/1.73 m², respectively, for estimated glomerular filtration rate (eGFR). Compared with the placebo group, eGFR decline was significantly slowed in both the responder and non-responder groups (P < 0.05).

Conclusion

Tolvaptan was effective in slowing eGFR decline, regardless of TKV response, over 3 years in patients with ADPKD in Japan. Treatment with tolvaptan may have beneficial effects on slowing of renal function decline even in patients who have not experienced a reduction in the rate of TKV growth by treatment with tolvaptan.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10157-020-02009-0.

N-Terminal Pro-B-Type Natriuretic Peptide and Incident CKD

Introduction

Serum N-terminal pro–B-type natriuretic peptide (NT-proBNP) levels have been associated with the progression of kidney impairment among patients with chronic kidney disease (CKD), but only a few studies have investigated the association between serum NT-proBNP levels and incident CKD in general populations.

Methods

A total of 2486 Japanese community-dwelling residents ≥40 years of age without CKD at baseline were followed up by repeated annual health examinations for 10 years. Participants were divided into 4 groups according to serum NT-proBNP levels. CKD was defined as an estimated glomerular filtration rate (eGFR) <60 ml/min/1.73m² or the presence of proteinuria. Cox proportional hazards models were used to estimate hazard ratios (HRs) for risk of CKD. Linear mixed models were used to compare changes in eGFR.

Results

During the follow-up period, 800 participants developed CKD. The multivariable-adjusted HRs (95% confidence intervals [CIs]) for developing CKD were 1.00 (reference), 1.32 (1.11–1.57), 1.40 (1.10–1.78), and 1.94 (1.38–2.73) for serum NT-proBNP levels of <55, 55–124, 125–299, and ≥300 pg/ml, respectively (P for trend <0.001). The decline of eGFR during the follow-up was significantly more rapid among participants with higher serum NT-proBNP levels (P for trend <0.001). Adding serum NT-proBNP to the model composed of known risk factors for CKD improved the predictive ability for developing CKD.

Conclusions

Higher serum NT-proBNP levels were associated with greater risks of developing CKD and greater decline in eGFR. Serum NT-proBNP could be a useful biomarker for assessing the future risk of CKD in a general Japanese population.

An Evaluation of Commonly Used Surrogate Baseline Creatinine Values to Classify AKI During Acute Infection

Introduction

Classification of acute kidney injury (AKI) requires a premorbid baseline creatinine, often unavailable in studies in acute infection.

Methods

We evaluated commonly used surrogate and imputed baseline creatinine values against a "reference" creatinine measured during follow-up in an adult clinical trial cohort. Known AKI incidence (Kidney Disease: Improving Global Outcomes [KDIGO] criteria) was compared with AKI incidence classified by (1) back-calculation using the Modification of Diet in Renal Disease (MDRD) equation with and without a Chinese ethnicity correction coefficient; (2) back-calculation using the Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) equation; (3) assigning glomerular filtration rate (GFR) from age and sex-standardized reference tables; and (4) lowest measured creatinine during admission. Back-calculated distributions were performed using GFRs of 75 and 100 ml/min.

Results

All equations using an assumed GFR of 75 ml/min underestimated AKI incidence by more than 50%. Back-calculation with CKD-EPI and GFR of 100 ml/min most accurately predicted AKI but misclassified all AKI stages and had low levels of agreement with true AKI diagnoses. Back-calculation using MDRD and assumed GFR of 100 ml/min, age and sex-reference GFR values adjusted for good health, and lowest creatinine during admission performed similarly, best predicting AKI incidence (area under the receiver operating characteristic curves [AUC ROCs] of 0.85, 0.87, and 0.85, respectively). MDRD back-calculation using a cohort mean GFR showed low total error (22%) and an AUC ROC of 0.85.

Conclusion

Current methods for estimating baseline creatinine are large sources of potential error in acute infection studies. Preferred alternatives include MDRD equation back-calculation with a population mean GFR, age- and sex-specific GFR values corrected for "good health," or lowest measured creatinine. Studies using surrogate baseline creatinine values should report specific methodology.

The Association of Small Dense Low-Density Lipoprotein Cholesterol and Coronary Heart Disease in Subjects at High Cardiovascular Risk

AIM

The present study aims to investigate the association between serum small dense low-density lipoprotein (sdLDL) cholesterol level and the development of coronary heart disease (CHD) in subjects at high cardiovascular risk.

METHODS

A total of 3,080 participants without prior cardiovascular disease (CVD), aged ≥ 40 years, were followed up for a median of 8.3 years, which were divided into two groups, those with serum sdLDL cholesterol levels of ＜35 mg/dL or ≥ 35 mg/dL. Then, subjects were stratified by the status of diabetes, CVD-related comorbidities (defined as the presence of diabetes, chronic kidney disease, or peripheral artery disease), and the CVD risk assessment according to the Japan Atherosclerosis Society Guidelines. The hazard ratios (HRs) and 95% confidence intervals (CIs) were computed using a Cox proportional hazards model.

RESULTS

During the follow-up, 79 subjects developed CHD. The risk for incident CHD was higher in subjects with serum sdLDL cholesterol of ≥ 35 mg/dL than those with sdLDL cholesterol of ＜35 mg/dL (HR 2.09, 95%CI 1.26-3.45) after adjusting for traditional risk factors. In the subgroup analyses, the multivariable-adjusted HR for incident CHD increased significantly in those with serum sdLDL cholesterol of ≥ 35 mg/dL among subjects with diabetes (HR 2.76, 95%CI 1.09-7.01), subjects with CVD-related comorbidities (HR 2.60, 95%CI 1.21-5.58), and high-risk category defined as the presence of CVD-related comorbidities or a Suita score of ≥ 56 points (HR 1.93, 95%CI 1.02-3.65).

CONCLUSIONS

Elevated serum sdLDL cholesterol was associated with the development of CHD even in subjects at high cardiovascular risk.

Association of the ratio of visceral-to-subcutaneous fat volume with renal function among patients with primary aldosteronism

Patients with primary aldosteronism have a higher risk of chronic kidney disease. Visceral fat tissue is hypothesized to stimulate the adrenal glands to overproduce aldosterone, and aldosterone promotes visceral fat tissue to produce inflammatory cytokines. However, it is unclear whether the volume of accumulated visceral fat tissue is associated with renal impairment among patients with hyperaldosteronism. We conducted a single-center cross-sectional study to assess the association between the estimated glomerular filtration rate and the ratio of the visceral-to-subcutaneous fat volume calculated by computed tomography. One hundred eighty patients with primary aldosteronism were enrolled. The mean ± SD age was 52.7 ± 11.0 years, and 60.0% were women. The ratio of visceral-to-subcutaneous fat volume was highly correlated with the estimated glomerular filtration rate (r = 0.49, p < 0.001). In multiple linear regression models, the ratio of visceral-to-subcutaneous fat tissue volume was significantly associated with the estimated glomerular filtration rate (estimates: -4.56 mL/min/1.73 m² per 1-SD), and there was an interaction effect between the plasma aldosterone concentration and the ratio of visceral-to-subcutaneous fat volume (p < 0.05). The group with a higher plasma aldosterone concentration exhibited a steeper decline in eGFR than the lower plasma aldosterone concentration group when the ratio increased. The ratio of visceral-to-subcutaneous fat tissue volume was an independent risk factor for renal dysfunction. This association increased in the presence of a high plasma aldosterone concentration. Clinicians should pay attention to the ratio of visceral-to-subcutaneous fat tissue volume and encourage primary aldosteronism patients to improve their lifestyle in addition to treating renin-aldosterone activity.

Association of self-reported moderate vegetable juice intake with small decline in kidney function in a five-year prospective study

OBJECTIVES

Although consumption of vegetable and 100% fruit juices are an acceptable alternative for vegetable and fruit intake, information about their actual effects on kidney function is sparse. The aim of this study was to determine the association between the consumption of vegetable and fruit juices and changes in kidney function in a Japanese population over a 5-y period.

METHODS

In this prospective study, we analyzed 2755 Japanese (742 men and 2013 women) individuals who participated in both the baseline and follow-up surveys in the Daiko study (a study within the Japan Multi-Institutional Collaborative Cohort study). Estimated glomerular filtration rate (eGFR) was calculated by age, sex, and serum creatinine level. For each beverage, we categorized all participants into four groups-rare (rarely consumed), low (≤2 cups/wk), moderate (3-4 cups/wk), or frequent (≥5 cups/wk) consumers of the beverage-based on a food frequency questionnaire.

RESULTS

The mean baseline and follow-up eGFR (SD) were 82.4 (14.6) and 72.2 (12.6), respectively. In fully adjusted regression analyses, moderate consumption of vegetable juice was associated a lower decline in eGFR compared with the rare consumption group (β = -1.30; P = 0.01). Moreover, stratified analyses revealed that this significant association remained in those who were young, female, non-obese, normotensive, smoked cigarettes, consumed alcohol, or exercised. However, no significant association was found in analyses for fruit juices.

CONCLUSIONS

This 5-y prospective study suggested an association between self-reported moderate consumption of vegetable juice and changes (possibly smaller decline) in kidney function in a relatively healthy Japanese population.

Validation of the D: A: D Chronic Kidney Disease Risk Score Model Among People Living With HIV in the Asia-Pacific

BACKGROUND

We validated the Data collection on Adverse events of anti-HIV Drugs (D:A:D) full-risk and short-risk score models for chronic kidney disease (CKD) in the Asian HIV cohorts.

SETTINGS

A validation study among people living with HIV (PLHIV) aged ≥18 years among the cohorts in the Asia-Pacific region.

METHODS

PLHIV with a baseline estimated glomerular filtration rate > 60 mL/min/1.73 m were included for validation of the D:A:D CKD full version and short version without cardiovascular risk factors. Those with <3 estimated glomerular filtration rate measurements from baseline or previous exposure to potentially nephrotoxic antiretrovirals were excluded. Kaplan-Meier methods were used to estimate the probability of CKD development. The area under the receiver operating characteristics was also used to validate the risk score.

RESULTS

We included 5701 participants in full model {median 8.1 [interquartile range (IQR) 4.8-10.9] years follow-up} and 9791 in short model validation [median 4.9 (IQR 2.5-7.3) years follow-up]. The crude incidence rate of CKD was 8.1 [95% confidence interval (CI): 7.3 to 8.9] per 1000 person-years in the full model cohort and 10.5 (95% CI: 9.6 to 11.4) per 1000 person-years in the short model cohort. The progression rates for CKD at 10 years in the full model cohort were 2.7%, 8.9%, and 26.1% for low-risk, medium-risk, and high-risk groups, and 3.5%, 11.7%, and 32.4% in the short model cohort. The area under the receiver operating characteristics for the full-risk and short-risk score was 0.81 (95% CI: 0.79 to 0.83) and 0.83 (95% CI: 0.81 to 0.85), respectively.

CONCLUSION

The D:A:D CKD full-risk and short-risk score performed well in predicting CKD events among Asian PLHIV. These risk prediction models may be useful to assist clinicians in identifying individuals at high risk of developing CKD.

Serum N-terminal pro-B-type natriuretic peptide as a predictor for future development of atrial fibrillation in a general population: the Hisayama Study

BACKGROUND

Biomarkers for predicting future development of atrial fibrillation (AF) have not been fully established in general populations. The aim of this study was to assess the predictive ability of serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) for the development of AF.

METHODS AND RESULTS

A total of 3126 community-dwelling Japanese subjects aged ≥ 40 years without a history of AF in 2002 were followed up for a median of 10.2 years. Serum NT-proBNP levels at baseline were divided into four categories (≤ 54, 55-124, 125-299, and ≥ 300 pg/mL) according to the current guidelines and prior reports. The hazard ratios for the development of AF were estimated using a Cox proportional hazards model. During the follow-up period, 153 subjects developed new-onset AF. The age- and sex-adjusted cumulative incidence of AF increased significantly with higher serum NT-proBNP levels (p < 0.001 for trend). The association remained significant after adjustment for known risk factors for AF and cardiovascular disease (hazard ratio [95% confidence interval]: ≤ 54 pg/mL: 1.00 [reference]; 55-124 pg/mL: 1.72 [1.00-2.97]; 125-299 pg/mL: 3.95 [2.23-6.98]; ≥ 300 pg/mL: 8.51 [4.48-16.17]; p < 0.001 for trend). Furthermore, incorporation of serum NT-proBNP levels into the model consisting of known risk factors for AF and cardiovascular disease significantly improved the predictive ability for developing AF (Harrell's c-statistics: 0.828 to 0.844, p = 0.01; continuous net reclassification improvement: 0.41, p < 0.001; integrated discrimination improvement: 0.031, p < 0.001).

CONCLUSIONS

Serum NT-proBNP levels can be a risk biomarker for predicting future development of AF in a general Japanese population.

Validation of the ABCD-GENE score to identify high platelet reactivity in east Asian patients undergoing percutaneous coronary intervention

BACKGROUND

High platelet reactivity (HPR) is associated with subsequent thrombotic events in patients undergoing percutaneous coronary intervention (PCI). Recently, the ABCD-GENE score was developed to identify patients at risk for HPR, incorporating both clinical and genetic factors. However, this score was derived and validated in mostly Caucasian subjects and it has not been validated in an East Asian population.

METHOD

Individual patient data from 4 prospective studies were pooled, in which platelet reactivity was measured using the VerifyNow assay on clopidogrel and genotyping of CYP2C19 was performed after PCI. Study populations included patients with general stable coronary artery disease, hemodialysis, age ≥75 and/or body weight <50 kg, and acute coronary syndrome. VerifyNow P2Y12 reactivity units >208 was defined as HPR.

RESULTS

Of 184 patients, 111 (60%) had HPR on clopidogrel. In the receiver operating characteristics curve analyses, the ABCD-GENE score significantly predicted HPR on clopidogrel (AUC 0.78, best cut-off value 9, p < 0.001). Across the 4 studies and their combinations, the diagnostic ability and cut-off values of ABCD-GENE score for HPR on clopidogrel were consistent.

CONCLUSIONS

The ABCD-GENE score had significant and moderate diagnostic ability for HPR on clopidogrel in Japanese patients undergoing PCI. The predictivity was consistent across a broad spectrum of patient populations, suggesting the applicability of this novel scoring system in clinical practice worldwide.

Association of Arterial Stiffness With Kidney Function Among Adults Without Chronic Kidney Disease

BACKGROUND

Our aims were to assess whether arterial stiffness is associated with a higher risk for kidney dysfunction among persons without chronic kidney disease (CKD).

METHODS

We analyzed data from the national health checkup system in Japan; for our analyses, we selected records of individuals who completed assessments of cardio-ankle vascular index (CAVI) and kidney function from 2005 to 2016. We excluded participants who had CKD at baseline, defined as the presence of proteinuria or estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m2. We compared 2 groups of CAVI measurements-the highest quartile (≧8.1) and the combined lower 3 quartiles (<8.1). We used Cox proportional hazards models to assess associations between these 2 groups and subsequent CKD events, proteinuria, eGFR <60 ml/min/1.73 m2, and rapid eGFR decline (greater than or equal to -3 ml/min/1.73 m2 per year).

RESULTS

The mean age of the 24,297 included participants was 46.2 years, and 60% were female. Over a mean follow-up of 3.1 years, 1,435 CKD events occurred. In a multivariable analysis, the hazard ratios with 95% confidence intervals (CIs) for the highest vs. combined lower quartiles of CAVI measurements were 1.3 (1.1, 1.5) for CKD events, 1.3 (0.96, 1.62) for proteinuria, 1.4 (1.1, 1.7) for eGFR <60 ml/min/1.73 m2, and the odds ratio with 95% CI was 1.3 (1.1, 1.4) for rapid eGFR decline.

CONCLUSIONS

Persons with CAVI measurements ≧8.1 had a higher risk for CKD events compared with their counterparts with CAVI measurements <8.1. Greater arterial stiffness among adults without CKD may be associated with kidney dysfunction.

High serum uric acid within the normal range is a useful predictor of hypertension among Japanese community-dwelling elderly women

Background

The risk associated with serum uric acid (SUA) levels when within the normal range is unknown. This study aims to examine whether SUA within the normal range is a predictor of hypertension.

Methods

The subjects comprised 704 men aged 71 ± 9 (mean ± standard deviation) years and 946 women aged 70 ± 8 years recruited for a survey at the community based annual medical check-up. The main outcome was the presence of hypertension (antihypertensive medication and/or having SBP ≥140 mmHg and/or DBP ≥90 mmHg).

Results

At baseline, 467 (66.3%) men and 608 (64.3%) women had hypertension. Comparing to lowest quartile in women (SUA-1, uric acid < 4.1 mg/dL), the unadjusted odds ratios (ORs) [95% confidence interval (CI)] for hypertension of SUA-2 (4.1 to 4.7 mg/dL), SUA-3 (4.8 to 5.4 mg/dL), and SUA-4 (≥5.5 mg/dL) were 1.11 (0.78–1.59), 1.75 (1.20–2.55), and 1.89 (1.30–2.77), respectively. These associations were apparent even after adjustments for age, but ORs were attenuated after adjusting for all confounding factors. During a follow-up of 3.0 years, there were 35 (24.0%) hypertension cases in men and 51 (20.8%) in women. In women only, a significant association between increased SUA categories and incidence of hypertension was observed, and the multivariate-ORs (95% (CI) for incident hypertension of SUA-3 (4.5–5.2 mg/dL) and SUA-4 (≥5.3 mg/dL) were 2.23 (0.81–6.11) and 3.84 (1.36–10.8), respectively.

Conclusions

These results suggest that baseline SUA within the normal range could be an important predictor for incidence of hypertension in Japanese community-dwelling elderly women.

Evaluation of postoperative kidney function after administration of 6% hydroxyethyl starch during living-donor nephrectomy for transplantation

PURPOSE

We aimed to investigate whether 6% HES 130/0.4 was associated with postoperative reduction of estimated glomerular filtration rate (eGFR) in donor patients who underwent nephrectomy for living kidney transplantation.

METHODS

This retrospective study included 213 living kidney transplant donors treated at Kyushu University Hospital in Japan from April 2014 to March 2018. Patients who were administered 6% HES 130/0.4 were allocated in the HES group (n = 108), and those who were not were allocated in the control group (n = 105). The postoperative decrements in estimated glomerular filtration rates (eGFRs) from preoperative values were calculated on postoperative days (PODs) 1, 3, and 14. Decline in kidney function (DKF) according to the Kidney Disease: Improving Global Outcomes (KDIGO) classification were analyzed by multivariable-adjusted ordinal logistic regression to estimate odds ratios (ORs) for postoperative DKF.

RESULTS

In HES group, administration amount of HES was median 9.4 [interquartile range: 8.2-14.3] ml/kg. Postoperative decrements in eGFR were similar in the control and HES groups on POD 1 (control group: mean 32.0 vs. HES group: 33.0 mL/min/1.73 m²), same as POD 3 (21.1 vs. 22.4 mL/min/1.73 m²) and POD 14 (26.0 vs. 25.9 mL/min/1.73 m²), even after adjusting for confounding factors. The multivariable-adjusted ORs for postoperative DKF did not significantly increase in the HES group on POD 1 (OR: 0.88), POD 3 (OR: 0.96), and POD 14 (OR: 0.52) compared with the control group.

CONCLUSION

Six percent HES 130/0.4 is not associated with postoperative renal dysfunction in donor patients undergoing nephrectomy for kidney transplantation.

In-Hospital Blood Pressure Variability: A Novel Prognostic Marker of Renal Function Decline and Cardiovascular Events in Patients with Coronary Artery Disease

INTRODUCTION

Several measures of blood pressure (BP) variability have been associated with kidney disease and cardiovascular events. Although BP is routinely measured during hospitalization in daily practice, the prognostic impact of in-hospital BP and its variability are uncertain.

METHODS

A total of 226 participants who underwent elective percutaneous coronary intervention (PCI) for stable coronary artery disease (CAD) were included. BP was measured by trained nurses during the 4-day hospitalization for PCI. BP variability was assessed by standard deviation (SD) and coefficient variation of systolic BP. Estimated glomerular filtration rate (eGFR) was calculated at baseline and follow-up (≥6 months). The cardiovascular end point was defined as a composite of cardiovascular death, acute coronary syndrome, stroke, heart failure hospitalization, and any coronary revascularization.

RESULTS

In-hospital BP was measured 9.5 ± 0.8 times. During a median follow-up period of 1.7 years, mean eGFR change was -1.7 mL/min/1.73 m2 per year, and 35 (15.5%) participants met the cardiovascular end point. Mean systolic BP and SD were negatively correlated with eGFR change. In the receiver operating characteristic curve analysis, SD of systolic BP predicted the cardiovascular end point (AUC 0.63, best cutoff value 14.2 mm Hg, p = 0.003). Kaplan-Meier analysis demonstrated a significantly higher incidence of the cardiovascular end point in patients with SD of systolic BP ≥14.2 mm Hg compared to their counterpart (p = 0.003). A multivariable analysis showed SD of systolic BP as an independent predictor for the cardiovascular end point. When assessed with coefficient variation, BP variability was similarly related to eGFR change and clinical outcomes.

CONCLUSION

Greater in-hospital BP variability was associated with renal function decline and cardiovascular events in patients with stable CAD.

Substantially Increased Plasma Coproporphyrin-I Concentrations Associated With OATP1B1*15 Allele in Japanese General Population

Coproporphyrin-I (CP-I) in plasma is a sensitive and specific endogenous probe for phenotyping organic anion transporting polypeptides 1B (OATP1B, encoded by SLCO1B). A few small-scale studies suggested that plasma CP-I concentration is affected by OATP1B1 polymorphism, but detailed studies are lacking. In this large-scale study, we measured plasma CP-I concentrations in 391 subjects from the Japanese general population, and evaluated the relationship between plasma CP-I concentrations and OATP1B1 polymorphisms to further assess the utility of plasma CP-I concentrations as an endogenous OATP1B probe. Plasma CP-I concentrations were 0.45 ± 0.12, 0.47 ± 0.16, 0.47 ± 0.20, 0.50 ± 0.15, 0.54 ± 0.14, and 0.74 ± 0.31 ng/mL in participants with OATP1B1*1b/*1b (n = 103), *1a/*1b (n = 122), *1a/*1a (n = 40), *1b/*15 (n = 74), *1a/*15 (n = 41), and *15/*15 (n = 11), respectively, showing an ascending rank order with significant difference (P < 0.0001). Post hoc analysis revealed significant increases in plasma CP-I concentration in OATP1B1*1b/*15 (P = 0.036), *1a/*15 (P = 0.0005), and *15/*15 (P = 0.0003) groups compared with the OATP1B1*1b/*1b group. There was no significant difference among OATP1B genotypes in plasma concentration of 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid, a uremic toxin reported to decrease OATP1B activity in vivo. These findings confirm the utility of plasma CP-I concentrations as an endogenous biomarker for phenotyping of OATP1B activity. Plasma CP-I concentration is potentially useful for the study of drug-drug interactions via OATP1B or individual dose adjustment of OATP1B substrates.

Trajectory of renal function change and kidney injury after percutaneous coronary intervention in patients with stable coronary artery disease

Acute kidney injury usually assessed within 48 h after percutaneous coronary intervention (PCI) is associated with poor clinical outcomes, and persistent kidney damage is also strongly related to long-term mortality. However, little is known about longitudinal renal function change from a very early period to long-term follow-up after PCI. A total of 327 patients with stable coronary artery disease underwent elective PCI. Renal function was assessed with serum creatinine levels and estimated glomerular filtration rate (eGFR) at baseline, 1 day after PCI, at 1 year and at the latest follow-up. Kidney injury was defined as an increase in creatinine levels ≥ 0.3 mg/dl or ≥ 50% from baseline at each timepoint. Major adverse cardiovascular events (MACE) was defined as a composite of death, myocardial infarction, and stroke. eGFR was significantly increased 1 day after PCI, while it was progressively decreased at 1-year and long-term follow-up (median 28 months). Overall, eGFR was declined by - 2.3 ml/min/1.73 m² per year. Only one (0.3%) patient developed kidney injury 1 day after PCI, whereas kidney injury at 1-year and long-term follow-up was observed in 15 (4.6%) and 27 (8.3%). During the follow-up period, 23 (7.0%) patients had MACE. The incidence of subsequent MACE was significantly higher in patients with kidney injury at 1 year than those without. In conclusion, kidney injury within 24 h after elective PCI was rarely observed. eGFR was progressively decreased over time, and mid-term kidney injury at 1 year was associated with future MACE.

Body mass index change and estimated glomerular filtration rate decline in a middle-aged population: health check-based cohort in Japan

BACKGROUND

Obesity is a growing public health problem worldwide. We evaluated the mediators and association between changes in obesity metrics and renal outcomes in the general population.

METHODS

Using the Japanese nationwide health check-based cohort from April 2011 to March 2019, we selected individuals aged 40-74 years, with a baseline estimated glomerular filtration rate (eGFR) ≥45 mL/min/1.73 m², whose body mass index (BMI) change was assessed. The primary outcome was combined 30% decline in eGFR, eGFR <15 mL/min/1.73 m² and end-stage renal disease.

RESULTS

During 245 147 person-years' follow-up among 50 604 participants (mean eGFR, 83.7 mL/min/1.73 m²; mean BMI, 24.1 kg/m²), 645 demonstrated eGFR decline (incidence rate 2.6/1000 person-years, 95% CI: 2.4 to 2.8). We observed continued initial changes in BMI for over 6 years and a U-shaped association between BMI change and eGFR decline. Compared with 0% change in BMI, adjusted HRs for changes of -10%, -4%, 4% and 10% were 1.53 (95% CI: 1.15 to 2.04), 1.14 (95% CI: 1.01 to 1.30), 1.16 (95% CI: 1.02 to 1.32) and 1.87 (95% CI: 1.25 to 2.80), respectively. The percentage of excess risk of BMI increase (>4%) mediated by three risk factors (blood pressure, haemoglobin A1c and total cholesterol), was 13.3%.

CONCLUSION

In the middle-aged Japanese population, both, increase and decrease in BMI were associated with subsequent eGFR decline. Changes in risk factors mediated a small proportion of the association between BMI increase and eGFR decline. Our findings support the clinical significance of monitoring BMI as a renal risk factor.

Decreased melatonin secretion in patients with glaucoma: Quantitative association with glaucoma severity in the LIGHT study

Glaucoma may be associated with circadian disruption due to its association with a loss of intrinsically photosensitive retinal ganglion cells. Clinical evidence demonstrating an association between glaucoma and circadian disruption is limited, and no large-scale studies have been performed. The purpose of this cross-sectional study was to determine whether the presence and severity of glaucoma is correlated with the urinary 6-sulfatoxymelatonin levels as a circadian rhythm parameter. We measured the level of urinary 6-sulfatoxymelatonin excretion (UME) in 118 glaucoma patients and 395 control participants without glaucoma. The UME in the glaucoma group was significantly lower than that of the control group without glaucoma (3.05 and 3.24 log ng/mg creatinine, respectively; P = .010). Next, we examined association of the severity of glaucoma and melatonin levels. In stratification analysis of the glaucoma groups, multivariable linear regression analyses adjusted for potential confounders indicated significantly lower UME by 0.30 log ng/mg creatinine in patients with functional severe glaucoma (visual field mean deviation ≤ -6 dB) compared with mild glaucoma (mean deviation > -6 dB; P = .040) and lower UME by 0.05 log ng/mg creatinine with each 10 μm thinning of the circumpapillary retinal nerve fiber layer thickness as the index of structural severity of glaucoma (P = .011). In conclusion, significant association between glaucoma and lower urinary 6-sulfatoxymelatonin was found. In addition, patients with functional and structural severe glaucoma were significantly associated with lower urinary 6-sulfatoxymelatonin levels. Our results indicate the possibility of a circadian disruption in patients with glaucoma.

Differences in longitudinal associations of cardiovascular risk factors with arterial stiffness and pressure wave reflection in middle-aged Japanese men

The present prospective observational study was conducted to examine the differences in longitudinal associations of the conventional risk factors for cardiovascular disease (CVD) with arterial stiffness and with abnormal pressure wave reflection using repeated measurement data. In 4016 healthy middle-aged (43 ± 9 years) Japanese men without CVD at baseline, the conventional risk factors for CVD, brachial-ankle pulse wave velocity (brachial-ankle PWV) and radial augmentation index (rAI) were measured annually over a 9-year period. Mixed-model linear regression analysis demonstrated a significant independent positive longitudinal association of the mean blood pressure with both the brachial-ankle PWV (estimate = 5.51, standard error = 0.30, P < 0.01) and the rAI (estimate = 0.19, standard error = 0.02, P < 0.01). On the other hand, the serum levels of glycohemoglobin, low-density lipoprotein cholesterol and triglycerides showed longitudinal associations only with the brachial-ankle PWV and not the rAI. In addition, while the radial AI was found to show a significant longitudinal association with the brachial-ankle PWV, the inverse association was not significant. In conclusion, the conventional risk factors for CVD showed heterogeneous longitudinal associations with arterial stiffness and/or abnormal pressure wave reflection. Elevated blood pressure showed independent longitudinal associations with both arterial stiffness (macrovascular damage) and abnormal pressure wave reflection, suggesting that BP is also longitudinally associated, at least in part, with microvascular damage. On the other hand, abnormal glucose metabolism and dyslipidemia showed independent longitudinal associations with only arterial stiffness (macrovascular damage).

Poor prognosis of heart failure patients with in-hospital worsening renal function and elevated BNP at discharge

Aims

Our purpose was to investigate the association between the B‐type natriuretic peptide (BNP) level at discharge, the occurrence of worsening renal function (WRF), and long‐term outcomes in patients with heart failure (HF).

Methods and results

We enrolled hospitalized acute HF patients. We divided patients into four groups on the basis of BNP <250 pg/mL (BNP−) or BNP ≥250 pg/mL (BNP+) at discharge and the occurrence of WRF during admission: BNP−/WRF−, BNP−/WRF+, BNP+/WRF−, and BNP+/WRF+. We evaluated the association between BNP at discharge, WRF, and cardiovascular/all‐cause mortality/hospitalization due to HF. Clinical follow‐up was completed in 301 patients. At discharge, percentages of the patients with clinical signs of HF were low and similar among four groups. The median follow‐up period was 1206 days (interquartile range, 733–1825 days). The composite endpoint of cardiovascular mortality and HF hospitalization was significantly different between the four groups [12.9% (BNP−/WRF−), 22.7% (BNP−/WRF+), 35.8% (BNP+/WRF−), and 55.4% (BNP+/WRF+), P < 0.0001]. All‐cause mortality was also different etween the four groups (15.1%, 38.6%, 28.7%, and 39.3%, respectively, P = 0.003). In the multivariate Cox proportional hazards model, the combination of BNP ≥250 pg/mL and WRF showed the highest hazard ratio (HR) for composite endpoint (HR, 5.201; 95% confidence interval, 2.582–11.11; P < 0.0001), and BNP−/WRF+ was associated with increased all‐cause mortality (HR, 2.286; 95% confidence interval, 1.089–4.875; P = 0.03). Patients in BNP+/WRF+ had a higher cardiovascular mortality (28.6%), and those in BNP−/WRF+ had a high non‐cardiovascular mortality (29.5%).

Conclusions

Heart failure patients with BNP ≥250 pg/mL at discharge and in‐hospital occurrence of WRF had the highest risk for the composite endpoint (cardiovascular mortality and HF hospitalization) among groups.

Neutrophil-to-lymphocyte ratio is a predictor of renal dysfunction in Japanese patients with type 2 diabetes

BACKGROUND

Neutrophil-to-lymphocyte ratio (NLR) has been widely evaluated as a biomarker in various medical and surgical prognoses, but its usefulness in diabetic kidney disease is not yet known.

METHODS

This prospective observational study included outpatients, comprised of 184 men aged 73 ± 11 (mean ± standard deviation) years and 174 women aged 76 ± 10 years at baseline, from a rural hospital. We examined the relationship between baseline NLR calculated by analyzing the differential leukocyte counts in the complete blood count and the 2-year estimated glomerular filtration rate (eGFR) decline rate (i.e. 2-year eGFR-baseline eGFR) ∗100/baseline eGFR. Rapid eGFR decline rate was defined as a value < -25%.

RESULTS

Multiple linear regression analysis using rapid eGFR decline rates as objective variables, adjusted for confounding factors as explanatory variables, showed that NLR (β = 0.138, p = 0.007) as well as presence of antidyslipidemic medication, hemoglobinA1c, and urinary albumin excretion stage were significantly and independently associated with a rapid eGFR decline rate. The multivariate-adjusted odds ratios (95% confidence interval) of the 2nd and 3rd tertiles of baseline NLR for rapid eGFR decline rate were 3.62 (0.70-18.7) and 8.03 (1.54-41.9), respectively. Multivariate-adjusted mean eGFR (95% confidence interval) values after 2 years categorized by tertile of baseline NLR were: 1st, 63.9 (61.8-66.1); 2nd, 60.8 (58.7-62.9); and 3rd, 58.9 (56.8-61.0).

CONCLUSIONS

These results suggest that baseline NLR might be a useful biomarker for renal function decline in outpatients with diabetes.

Associations Between Changes in Plasma Renin Activity and Aldosterone Concentrations and Changes in Kidney Function After Treatment for Primary Aldosteronism

Introduction

Greater reduction in estimated glomerular filtration rate (eGFR) after specific treatment for primary aldosteronism (PA) reflects improvement in glomerular hyperfiltration associated with PA and leads to better patient outcomes. However, little is known regarding the mechanisms underlying eGFR reduction after treatment for PA.

Methods

We analyzed data from the nationwide PA registry in Japan. Patients were assigned to adrenalectomy (n = 438) and mineralocorticoid receptor (MR) antagonist (n = 746) groups. We assessed associations between changes in blood pressure (BP), plasma renin activity (PRA) and plasma aldosterone concentrations (PAC), and eGFR before and 6 months after treatment for both groups.

Results

In a multivariable linear regression, the adjusted β values (95% confidence interval [CI]) for change in eGFR after treatment were −2.76 (−4.29, −1.22) ml/min per 1.73 m² for PRA (per 3.2 ng/ml per hour), and 1.97 (1.08, 2.85) ml/min per 1.73 m² for PAC (per 236.1 pg/ml) in the adrenalectomy group; and −0.45 (−0.89, −0.01) ml/min per 1.73 m² for PRA and −0.72 (−1.62, 0.18) ml/min per 1.73 m² for PAC in the MR antagonist group. Change in mean arterial pressure after treatment was not significantly associated with change in eGFR in either group. Changes in PRA and PAC but not BP before and 6 months after treatment for PA were associated with greater reductions in eGFR.

Conclusion

Post-treatment improvements in glomerular hyperfiltration may be attributable to decreased MR activity in the kidneys, but not to reductions in systemic BP.

Proteinuria and Reduced Estimated Glomerular Filtration Rate are Independently Associated With Lower Cognitive Abilities in Apparently Healthy Community-Dwelling Elderly Men in Japan: A Cross-sectional Study

BACKGROUND

The association of proteinuria and reduced estimated glomerular filtration rate (eGFR) with cognition needs more clarification. We cross-sectionally examined whether proteinuria and reduced eGFR, even in moderate stages, were independently associated with lower cognition in a community-based sample of elderly men.

METHODS

Our cohort initially comprised 1,094 men aged 40-79 years from a random sample from Shiga, Japan in 2006-2008. Of 853 men who returned for the follow-up examination (2009-2014), we analyzed 561 who were ≥65 years, free of stroke, and completed the Cognitive Abilities Screening Instrument (CASI) at follow-up (higher CASI scores [range 0 to 100] indicate better cognition). Proteinuria was assessed via dipstick. eGFR was calculated according to the Chronic Kidney Disease Epidemiology Collaboration Equation. Participants were divided into three groups either by eGFR (≥60, 59-40, and <40 mL/min/1.73 m2) or by proteinuria (no, trace, and positive), considered normal, moderate, and advanced, respectively. Using linear regression, we computed mean CASI score, with simultaneous adjustment for proteinuria and eGFR in addition to other potential confounders.

RESULTS

Significant trends of lower cognition were observed across the groups of worse proteinuria and lower eGFR independently: multivariable-adjusted mean CASI scores were 90.1, 89.3, and 88.4 for proteinuria (Ptrend = 0.029), and 90.0, 88.5, and 88.5 for eGFR (Ptrend = 0.015) in mutual-adjustment model.

CONCLUSIONS

Proteinuria and reduced eGFR, even in their moderate stages, were independently associated with lower cognition in a community-based sample of elderly men. The results suggest the importance of proteinuria and low eGFR for early detection and prevention of cognitive decline.

Usefulness of the SAGE score to predict elevated values of brachial-ankle pulse wave velocity in Japanese subjects with hypertension

The score based on the office systolic blood pressure, age, fasting blood glucose level, and estimated glomerular filtration rate (SAGE score) has been proposed as a useful marker to identify elevated values of carotid-femoral pulse wave velocity (PWV). The present cross-sectional study was conducted to examine whether the SAGE score is also a useful marker to identify subjects with elevated brachial-ankle PWV values in Japanese subjects with hypertension. We measured the brachial-ankle PWV and calculated the SAGE score in a total of 1019 employees of a Japanese company with hypertension and 817 subjects with hypertension derived from a multicenter study cohort. The analyses in this study were based on data from these two study groups as well as on a composite population of the two (n = 1836). The receiver operating characteristic curve analysis showed that the area under the curve to identify subjects with brachial-ankle PWV values of ≥1800 cm/s was over 0.70 in each of the three study groups. Even after adjustments, a SAGE score ≥7 had a significant odds ratio for identifying subjects with brachial-ankle PWV values ≥1800 cm/s in the 1836 study subjects from the composite occupational and multicenter study cohort (odds ratio = 2.1, 95% confidence interval = 1.4-3.0, P < 0.01). Thus, in Japanese subjects with hypertension, the SAGE score may be a useful marker for identifying subjects with elevated brachial-ankle PWV values.

Increased body mass index above the upper normal limit is significantly associated with renal dysfunction among community-dwelling persons

PURPOSE

Body mass index (BMI) is a simple index of weight-to-height that is commonly used to classify people as underweight, overweight or obesity, and high BMI has been clearly linked to increased risk of illness in adults. However, few studies have examined the significance of upper normal weight as a risk factor for the development of chronic kidney disease (CKD) in the general Japanese population.

METHODS

We conducted a prospective cohort study designed as part of the Nomura study. We recruited a random sample of 421 men aged 67 ± 10 (mean ± standard deviation; range 24-95) years and 565 women aged 68 ± 9 (22-84) years during their annual health examination in a single community. We examined the relationship between quartiles of baseline BMI and renal dysfunction after a 3-year evaluation based on estimated glomerular filtration rate (eGFR) using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations modified by the Japanese coefficient. CKD was defined as having dipstick-positive proteinuria (≥ 1 +) or a low eGFR (< 60 mL/min/1.73 m²).

RESULTS

Of the 986 participants, a total of 134 (13.6%) participants, including 72 (17.1%) men and 62 (11.0%) women, received a new diagnosis of CKD during the study period, and 25 (9.7%), 19 (8.0%), 47 (19.0%), and 43 (17.8%) diagnoses were received in the BMI-1 (BMI, < 20.7 kg/m²), BMI-2 (BMI, 20.7 to 22.5 kg/m²), BMI-3 (BMI, 22.6 to 24.4 kg/m²), and BMI-4 (BMI ≥ 24.5 kg/m²) groups, respectively. Using BMI-2 as the reference group, the non-adjusted odds ratio (OR) (95% confidence interval) for CKD was 2.70 (1.53-4.75) for BMI-3 and 2.49 (1.40-4.42) for BMI-4, and the multivariable-adjusted OR was 2.52 (1.40-4.56) for BMI-3 and 2.30 (1.26-4.22) for BMI-4.

CONCLUSIONS

Increased BMI from upper normal weight is strongly associated with the development of CKD in community-dwelling persons.

Association of Albuminuria With White Matter Hyperintensities Volume on Brain Magnetic Resonance Imaging in Elderly Japanese - The Hisayama Study

BACKGROUND

Both chronic kidney disease and brain white matter hyperintensities (WMH) are known to be risk factors of dementia and mortality.

METHODS AND RESULTS

In 2012, 1,214 community-dwelling Japanese subjects aged ≥65 years underwent brain magnetic resonance imaging (MRI) scans and a comprehensive health examination. This study investigated associations of the urinary albumin : creatinine ratio (UACR) and estimated glomerular filtration rate (eGFR) with the WMH volume to intracranial volume (WMHV : ICV) ratio, and the association of the combination of UACR and the WMHV : ICV ratio with cognitive decline and mortality risk. The geometric mean of the WMHV : ICV ratio was 0.223% in the entire study population, and increased significantly with higher UACR levels after adjusting for potential confounding factors (0.213% for normoalbuminuria, 0.248% for microalbuminuria, and 0.332% for macroalbuminuria; Ptrend=0.01). In contrast, there was no clear association between eGFR and the WMHV : ICV ratio. Compared with subjects with normoalbuminuria and a smaller WMHV : ICV ratio (<0.257% [median]), subjects with albuminuria and a larger WMHV : ICV ratio (≥0.257%) had higher probabilities of cognitive decline at baseline and all-cause death during the follow-up.

CONCLUSIONS

This study suggests that subjects with albuminuria have a greater risk of WMH enlargement and that the combination of albuminuria and WMH enlargement increases the risk of cognitive decline and all-cause mortality in an elderly Japanese population.

Usefulness of waist-to-height ratio in screening incident hypertension among Japanese community-dwelling middle-aged and elderly individuals

Background

The incidence of hypertension is increasing worldwide and obesity is one of the most significant risk factors. Obesity can be defined by various anthropometric indices such as body mass index (BMI), waist-to-hip ratio (WHpR), and waist-to-height ratio (WHtR). This study examined a range of anthropometric indices and their relationships with hypertension.

Methods

This study included 768 men aged 70 ± 10 years and 959 women aged 70 ± 8 years from a rural village. The relationship between anthropometric indices (BMI, WHpR, and WHtR) and hypertension was examined using cross-sectional (baseline, N = 1727) and cohort data (follow-up, N = 419). Receiver operating characteristic (ROC) analysis was used to determine the predictive ability of obesity indices for hypertension in both genders. Logistic regression models were used to evaluate WHtR as a significant predictor of hypertension.

Results

In the cross-sectional study, WHtR, BMI, and WHpR showed significant predictive abilities for hypertension in both genders, with WHtR showing the strongest predictive ability. Also, in the cohort study, WHtR showed a significant predictive ability for incident hypertension in both genders, and, for women, BMI as well as WHtR had also predictive ability. In the cross-sectional study, the optimal WHtR cutoff values were 0.53 (sensitivity, 44.3%; specificity, 80.2%) for men and 0.54 (sensitivity, 60.9%; specificity, 68.6%) for women. In the cohort study, the optimal WHtR values were 0.47 (sensitivity, 85.4%; specificity, 39.8%) for men and 0.51 (sensitivity, 66.7%; specificity, 58.2%) for women.

Conclusions

The results suggest that WHtR is a useful screening tool for hypertension among Japanese middle-aged and elderly community-dwelling individuals.

Additional prognostic value of electrocardiographic left ventricular hypertrophy in traditional cardiovascular risk assessments in chronic kidney disease

BACKGROUND

Left ventricular hypertrophy (LVH) is a common predictor of the cardiovascular prognosis in chronic kidney disease (CKD). However, whether or not electrocardiography-derived LVH (ECG-LVH) has prognostic value in patients with various degrees of CKD and improves the cardiovascular risk stratification based on traditional risk factors remains unclear.

METHODS

A total of 7206 participants at least 40 years of age who were free from cardiovascular events in a general population were followed for the incidence of cardiovascular events. CKD was confirmed by either the presence of a reduced estimated glomerular filtration rate (eGFR) (<60 ml/min per 1.73 m) or albuminuria, defined as a urinary albumin-to-creatinine ratio (UACR) of at least 30 mg/g Cr.

RESULTS

A total of 1886 (26.2%) had CKD, of which 1471 (78.0%) had a preserved eGFR (CKD stage 1-2). After an average 11.3 years of follow-up, the adjusted hazard ratio for the incidence of cardiovascular events significantly increased for ECG-LVH according to the Sokolow--Lyon voltage, Cornell voltage, or Cornell voltage product among participants with CKD (hazard ratio 1.47, P = 0.002), in contrast to those without CKD (hazard ratio 1.15, P = 0.210). The inclusion of any ECG-LVH parameters improved the accuracy of reclassification in any risk prediction model based on the eGFR, UACR, or Framingham 10-year risk score in the CKD participants (net reclassification improvement = 0.13-0.32, all P values <0.040).

CONCLUSION

In patients with CKD stage 1-5, ECG-LVH is useful for predicting the risk of future cardiovascular events and adds prognostic information to traditional cardiovascular risk assessments.

Association between exposure to the Chinese famine during early life and the risk of chronic kidney disease in adulthood

BACKGROUND AND OBJECTIVES

Famine exposure in human early life is proven to be associated with urinary protein concentration and renal function but has not been studied with chronic kidney disease. We aimed to explore the association between exposure to the Chinese famine (from 1959 to 1962) in early life and the risk of chronic kidney disease in adulthood.

DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS

We selected 6267 participants from the baseline survey of China Health and Retirement Longitudinal Study (CHARLS) 2011-2012. Based on the birth year, they were divided into fetal exposed, preschool exposed, school-aged exposed, and non-exposed groups. The estimated glomerular filtration rate (eGFR) was calculated according to Japanese coefficient-modified Chronic Kidney Disease Epidemiology Collaboration equation. Chronic kidney disease (CKD) was defined as eGFR less than 60 mL/min per 1.73 m².

RESULTS

The prevalence of CKD in fetal exposed, preschool exposed, school-aged exposed and non-exposed groups was 4.27%, 5.41%, 9.65% and 2.42%, respectively. The risk of CKD in fetal exposed, preschool exposed and school-aged exposed groups was significantly higher than the non-exposed group. In addition, after stratification by gender and famine severity, we found that only fetal exposure to the severe famine was associated with the elevated risk of CKD among male adults (OR 4.44, 95%CI 1.10-17.92, P < 0.05), even after adjusting for age, marital status, household per capita income, history of kidney disease, hypertension, diabetes or abnormal glucose tolerance, smoking, drinking, rural/urban residence and highest educational attainment of parents.

CONCLUSIONS

Severe famine exposure as a fetus might increase the risk of chronic kidney disease in male adults.

Serum homocysteine and risk of dementia in Japan

OBJECTIVE

To examine the association between serum total homocysteine levels (tHcy) and dementia risk.

METHODS

A total of 1588 Japanese adults aged ≥60 years without dementia were prospectively followed from 2002 to 2012. Cox proportional hazards models and restricted cubic splines were used to estimate the HRs of tHcy levels on the risk of dementia.

RESULTS

During the follow-up, 372 subjects developed all-cause dementia; 247 had Alzheimer's disease (AD) and 98 had vascular dementia (VaD). Compared with the lowest tHcy quintile (≤6.4 µmol/L), the multivariable-adjusted HRs (95% CI) of the highest quintile (≥11.5 µmol/L) were 2.28 (1.51-3.43) for all-cause dementia, 1.96 (1.19-3.24) for AD and 2.51 (1.14-5.51) for VaD. In restricted cubic splines, the risk of all-cause dementia steadily increased between approximately 8-15 µmol/L and plateaued thereafter, with a similar non-linear shape observed for AD and VaD (all p for non-linearity ≤0.02). In stratified analyses by the most recognised genetic polymorphism affecting tHcy concentrations (methylenetetrahydrofolate reductase C677T), the positive association of tHcy with all-cause dementia persisted in both non-carriers and carriers of the risk allele, and even tended to be stronger in the former (p for heterogeneity=0.07).

CONCLUSION

High serum tHcy levels are associated with an elevated risk of dementia, AD and VaD in a non-linear manner, such that an exposure-response association is present only within a relatively high range of tHcy levels. Non-genetic factors affecting serum tHcy concentrations may play important roles in tHcy-dementia associations irrespective of the genetic susceptibility for raised tHcy.

Long-Term Effects of High-Dose Tolvaptan for Autosomal Dominant Polycystic Kidney Disease Patients

Tolvaptan, a vasopressin V₂ receptor antagonist, was initially approved in Japan for treatment of autosomal dominant polycystic kidney disease (ADPKD). Recently, a retrospective study showed that the effect of tolvaptan on kidney function could be sustained for a long period. However, the long-term efficacy and safety of high-dose tolvaptan (120 mg/day) in individual cases remain unknown. We report here 2 Japanese ADPKD patients (males, 36 and 29 years old) treated with tolvaptan (120 mg/day) for 9 years, during which time determinations of estimated glomerular filtration rate (eGFR) and total kidney volume (TKV) were performed. In these 2 patients, eGFR prior to therapy was 57.3 and 76.3 mL/min/1.73 m², respectively, and 30.2 and 43.5 mL/min/1.73 m², respectively, after 9 years of tolvaptan treatment, for a relatively constant annual decline of −3.01 and −3.64 mL/min/1.73 m², respectively. As compared to the predicted (calculated) eGFR without tolvaptan treatment, eGFR actually measured was higher by 15.3 and 12.6 mL/min/1.73 m², respectively, after the 9-year therapy period. In addition, the rate of TKV increase was gradual, 2.4 and 4.7%, respectively, per year during the initial 3-year period, to 6.5 and 12.5%, respectively, per year in the following 6-year period. During the 9 years of treatment, neither patient showed tolvaptan-related adverse events. Our findings suggest that long-term administration of tolvaptan at a high dose is both safe and effective to preserve kidney function, though a gradual increase in TKV was seen in both of the present cases, particularly during the later phase.

Implications of early diagnosis of autosomal dominant polycystic kidney disease: A post hoc analysis of the TEMPO 3:4 trial

It is unknown whether early diagnosis of autosomal dominant polycystic kidney disease (ADPKD) can enable earlier management and improve outcomes. We conducted a post hoc analysis of data from the TEMPO 3:4 trial. Subjects were stratified by ADPKD diagnosis at age ≤18 (childhood diagnosis [CD]) or>18 (adulthood diagnosis [AD]). Groups were compared for baseline characteristics and total kidney volume (TKV) growth and estimated glomerular filtration rate (eGFR) decline over 3 years. 294 CD and 1148 AD subjects were analyzed. At inclusion, CD subjects were younger (mean age 34.2 versus 39.8 years; p < 0.0001) and had better eGFR (mean ± SD 87.4 ± 23.9 versus 80.1 ± 20.7 mL/min/1.73 m²; p < 0.0001), while CD had more severe Mayo risk classification (p < 0.0001) and more PKD1 mutations (p = 0.003). No statistical differences were found in TKV or eGFR change. At study end, placebo-treated CD subjects had better eGFR than projected by a prediction equation (mean difference ±SD for observed versus predicted eGFR: 2.18 ± 10.7 mL/min/1.73 m²; p = 0.0475). However, these results are not confirmed when excluding stage 1 CKD. Whether CD subjects, despite their risk profile, have a slower disease course than predicted remains inconclusive. Future studies are needed to confirm that early diagnosis and management can alter the disease course of ADPKD.

Ratios of serum eicosapentaenoic acid to arachidonic acid and docosahexaenoic acid to arachidonic acid were inversely associated with serum resistin levels: The Hisayama Study

AIMS/INTRODUCTION

Resistin is an adipocyte-derived polypeptide that leads to the progression of insulin resistance and subsequent atherosclerosis. Some studies have reported an association between self-reported intake of n-3 polyunsaturated fatty acids (PUFAs) and serum resistin levels. However, no studies have investigated the association between the ratio of serum levels of n-3 to serum n-6 PUFAs and the serum resistin concentration in the general population.

MATERIALS AND METHODS

We carried out a cross-sectional study of 3,200 community-dwelling Japanese individuals aged ≥40 years in 2002-2003. The ratios of serum eicosapentaenoic acid or docosahexaenoic acid to arachidonic acid (AA) were categorized into quartiles. The associations of serum eicosapentaenoic acid/AA and docosahexaenoic acid/AA with the serum resistin concentration were assessed using linear regression models with adjustment for potential confounding factors.

RESULTS

The geometric mean of serum resistin was 10.3 ng/mL. The age- and sex-adjusted geometric mean of serum resistin decreased significantly with increased levels of serum eicosapentaenoic acid/AA (quartile 1: 11.3 ng/mL; quartile 2: 10.6 ng/mL; quartile 3: 10.3 ng/mL; quartile 4: 9.3 ng/mL; P for trend <0.001). A similar association was observed for serum docosahexaenoic acid/AA (quartile 1: 11.1 ng/mL; quartile 2: 10.6 ng/mL; quartile 3: 10.1 ng/mL; quartile 4: 9.7 ng/mL; P for trend <0.001). An adjustment for potential confounding factors did not change these associations.

CONCLUSIONS

Higher ratios of serum n-3 to n-6 PUFAs were associated with lower serum resistin levels. Consumption of a large amount of n-3 PUFAs might have desirable effects on resistin-mediated diseases.

Interactive association of baseline and changes in serum uric acid on renal dysfunction among community-dwelling persons

BACKGROUND

Chronic kidney disease (CKD) is a major public health concern. Baseline serum uric acid (SUA) levels were independently associated with incident renal dysfunction, but whether baseline and changes in SUA produce an interactive effect on renal dysfunction remains unclear.

METHODS

The subjects comprised 460 men aged 68 ± 10 (mean ± standard deviation) years and 635 women aged 68 ± 9 years from a rural village. We have found participants who underwent a similar examination 3 years later, and analyzed the relationship between baseline SUA, changes in SUA, and a 3-year follow-up renal function evaluated by estimated glomerular filtration rate (eGFR).

RESULTS

A total of 93 (20.2%) men and 76 (12.0%) women had hyperuricemia (men: SUA ≥ 7.0 mg/dL and women: SUA ≥ 6.0 mg/dL) at baseline. Multiple regression analysis using changes in eGFR as objective variable, adjusted for risk factors as explanatory variables, showed that the baseline SUA and changes in SUA were linearly associated with changes in eGFR (β = －0.115, P < .001 and β = －0.431, P < .001, respectively). In both normal SUA group and hyperuricemia group, changes in SUA significantly associated with changes in eGFR (β = －0.473, P < .001 and β = －0.197, P = .009, respectively). Participants with increased SUA from normal to hyperuricemia group had greater eGFR decline over the follow-up period, and their multivariate-adjusted 3-year follow-up eGFR was significantly lower than in other groups (P < .001).

CONCLUSION

Our data demonstrated that baseline and longitudinal changes in SUA were independently and interactively associated with the renal function decline among community-dwelling persons.

Agreement and Precision Analyses of Various Estimated Glomerular Filtration Rate Formulae in Cancer Patients

The accuracy of the estimated glomerular filtration rate (eGFR) in cancer patients is very important for dose adjustments of anti-malignancy drugs to reduce toxicities and enhance therapeutic outcomes. Therefore, the performance of eGFR equations, including their bias, precision, and accuracy, was explored in patients with varying stages of chronic kidney disease (CKD) who needed anti-cancer drugs. The reference glomerular filtration rate (GFR) was assessed by the ^99mTc-diethylene triamine penta-acetic acid (^99mTc-DTPA) plasma clearance method in 320 patients and compared with the GFRs estimated by i) the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation, ii) the unadjusted for body surface area (BSA) CKD-EPI equation, iii) the re-expressed Modification of Diet in Renal Disease (MDRD) study equation with the Thai racial factor, iv) the Thai eGFR equation, developed in CKD patients, v) the 2012 CKD-EPI creatinine-cystatin C, vi) the Cockcroft-Gault formula, and vii) the Janowitz and Williams equations for cancer patients. The mean reference GFR was 60.5 ± 33.4 mL/min/1.73 m². The bias (mean error) values for the estimated GFR from the CKD-EPI equation, BSA-unadjusted CKD-EPI equation, re-expressed MDRD study equation with the Thai racial factor, and Thai eGFR, 2012 CKD-EPI creatinine-cystatin-C, Cockcroft-Gault, and Janowitz and Williams equations were -2.68, 1.06, -7.70, -8.73, 13.37, 1.43, and 2.03 mL/min, respectively, the precision (standard deviation of bias) values were 6.89, 6.07, 14.02, 11.54, 20.85, 10.58, and 8.74 mL/min, respectively, and the accuracy (root-mean square error) values were 7.38, 6.15, 15.97, 14.16, 24.74, 10.66, and 8.96 mL/min, respectively. In conclusion, the estimated GFR from the BSA-unadjusted CKD-EPI equation demonstrated the least bias along with the highest precision and accuracy. Further studies on the outcomes of anti-cancer drug dose adjustments using this equation versus the current standard equation will be valuable.

Brachial-Ankle Pulse Wave Velocity Versus Its Stiffness Index β-Transformed Value as Risk Marker for Cardiovascular Disease

Background

The difference in the predictive ability of the brachial‐ankle pulse wave velocity (baPWV) and its stiffness index β‐transformed value (β‐baPWV, ie, baPWV adjusted for the pulse pressure) for the development of pathophysiological abnormalities related to cardiovascular disease or future occurrence of cardiovascular disease was examined.

Methods and Results

In study 1, a 7‐year prospective observational study in cohorts of 3274 men and 3490 men, the area under the curve in the receiver operator characteristic curve analysis was higher for baPWV than for β‐baPWV for predicting the development of hypertension (0.73, 95% CI=0.70 to 0.75 versus 0.59, 95% CI=0.56 to 0.62; P<0.01) and/or the development of retinopathy (0.78, 95% CI=0.73 to 0.82 versus 0.66, 95% CI=0.60 to 0.71; P<0.01) by the end of the study period. During study 2, a 3‐year observation period on 511 patients with coronary artery disease, 72 cardiovascular events were confirmed. The C statistics of both markers for predicting the development of cardiovascular events were similar.

Conclusions

Stiffness index β transformation of the baPWV may attenuate the significance of the baPWV as a risk marker for development of pathophysiological abnormalities related to cardiovascular disease in male subjects.

Ankle-Brachial Index is a Predictor of Future Incident Chronic Kidney Disease in a General Japanese Population

AIMS

The ankle-brachial index (ABI) can be a prognostic marker for chronic kidney disease (CKD) in Western populations. Since there is little relevant evidence for Asian populations, we investigated the relationship between ABI and the risk of incident CKD in a general Japanese population.

METHODS

The cohort included 5,072 participants aged 30-79 without a history of renal disease or cerebro-cardiovascular disease. Incident CKD, defined as an estimated glomerular filtration rate ＜60 (mL/min/1.73 m2) and/or proteinuria (≥ 1＋ on urine dipstick), was compared among participants grouped according to baseline ABI: 0.90-0.99, 1.00-1.09, 1.10-1.19, 1.20-1.29, and 1.30-1.39. Hazard ratios for incident CKD were estimated using a Cox proportional hazards model, with the ABI 1.10-1.19 group serving as the reference.

RESULTS

The CKD incidence rate (/100 person-years) was 1.80 during the mean follow-up period of 5.1 years. The CKD incidence rate was 3.04 in the ABI category 0.90-0.99, 1.58 in ABI 1.00-1.09, 1.72 in ABI 1.10-1.19, 2.01 in ABI 1.20-1.29, and 3.33 in ABI 1.30-1.39. The hazard ratios for developing CKD were 2.14 (95% confidence interval 1.16-3.92) in ABI 0.90-0.99, 1.08 (0.83-1.41) in ABI 1.00-1.09, 1.03 (0.83-1.29) in ABI 1.20-1.29, and 1.37 (0.77-2.47) in ABI 1.30-1.39, after adjusting for age, sex, systolic blood pressure, diabetes, and other confounding factors.

CONCLUSIONS

In a general Japanese population, an ABI of 0.90-0.99 was associated with an increased risk of incident CKD, independent of traditional cardiovascular risk factors.

Nudging patients with chronic kidney disease at screening to visit physicians: A protocol of a pragmatic randomized controlled trial

BACKGROUND/AIMS

Strategies for an effective intervention after chronic kidney disease (CKD) screening have not been well examined. We describe the rationale and design of a protocol of a pragmatic randomized controlled trial (RCT) to test the effect of a behavioral intervention using the nudge approach in behavioral economics on CKD patients' visiting behaviors to physicians and change in their kidney function after CKD screening.

METHODS

The RCT will include CKD patients (N = 4500) detected at screening (estimated glomerular filtration rate [eGFR] <60 mL/min/1.74 m2 or urine protein ≥1+), aged 40-63 years. The two intervention groups will receive a "usual letter" and "nudge-based letter," while the control group will only receive a conventional follow-up. Our primary outcome is proportion of patients' visiting physicians for 6 months after the intervention; the secondary outcome is change in the eGFR at 2 years after the intervention.

RESULTS

We developed an efficient intervention program after CKD screening and designed the pragmatic RCT to assess its effectiveness in the real world. Our trial is unique in that it investigates the effect of the nudge approach in behavioral economics. By the end of 2018, we have enrolled 1,692 participants, and randomized 677 participants into the usual letter group, 677 participants into the nudge-based letter group, and 338 participants into the control group. We have confirmed that health checkup data could identify a large number of eligible participants.

CONCLUSION

The trial's results will contribute to filling in the gap between screening and subsequent medical interventions for preventing CKD progression.

Demonstration of Improved Renal Congestion After Heart Failure Treatment on Renal Perfusion Imaging With Contrast-Enhanced Ultrasonography

Background: Renal congestion is a critical pathophysiological component of congestive heart failure (CHF). Methods and Results: To quantify renal congestion, contrast-enhanced ultrasonography (CEUS) was performed at baseline and after treatment in 11 CHF patients and 9 normal subjects. Based on the time-contrast intensity curve, time to peak intensity (TTP), which reflects the perfusion rate of renal parenchyma, and relative contrast intensity (RCI), an index reflecting renal blood volume, were measured. In CHF patients, TTP at baseline was significantly prolonged compared with that in controls (cortex, 10.8±3.5 vs. 4.6±1.2 s, P<0.0001; medulla, 10.6±3.0 vs. 5.1±1.6 s, P<0.0001), and RCI was lower than that in controls (cortex, -16.5±5.2 vs. -8.8±1.5 dB, P<0.0001; medulla, -22.8±5.2 vs. -14.8±2.4 dB, P<0.0001). After CHF treatment, RCI was significantly increased (cortex, -16.5±5.2 to -11.8±4.5 dB, P=0.035; medulla, -22.8±5.2 to -18.7±3.7 dB, P=0.045). TTP in the cortex decreased after treatment (10.8±3.5 to 7.6±3.1 s, P=0.032), but it was unchanged in the medulla (10.6±3.0 to 8.3±3.2 s, P=0.098). Conclusions: Renal congestion can be observed using CEUS in CHF patients.

Isolated low levels of high-density lipoprotein cholesterol and stroke incidence: JMS Cohort Study

Background

The cardiovascular relevance of isolated low levels of high‐density lipoprotein cholesterol (HDL‐C) is yet to be determined. Stroke often leads to long‐term disability, and thus, not only stroke mortality but also stroke incidence is a topic of research. Although isolated low HDL‐C level has been found to be a predictor for stroke mortality previously, whether it can predict stroke incidence is unknown.

Methods

In the Jichi Medical School cohort study, 11 025 community‐living residents without a history of stroke were examined. Hazard ratios (HRs) for isolated and non‐isolated low HDL‐C levels were calculated relative to those for normal HDL‐C levels in stroke patients using Cox's regression models.

Results

During the mean follow‐up period of 10.7 years, 412 residents had their first‐ever stroke. The multivariable‐adjusted HRs for the levels of isolated and non‐isolated low HDL‐C were 1.11 (95% confidence interval, 0.85‐1.44) and 1.35 (1.01‐1.81), respectively, when compared to that for normal HDL‐C.

Conclusion

Low HDL‐C levels with other dyslipidemias may contribute to the incidence of stroke, not isolated low HDL‐C.

Small Dense Low-Density Lipoprotein Cholesterol and the Risk of Coronary Heart Disease in a Japanese Community

Aims: This study aims to investigate the association between serum small dense low-density lipoprotein (sdLDL) cholesterol level and the development of coronary heart disease (CHD) in a Japanese community.

Methods: A total of 3,080 participants without prior cardiovascular disease, aged 40 years or older, were followed up for 8 years. The participants were divided into the quartiles of serum sdLDL cholesterol levels. The risk estimates were computed using a Cox proportional hazards model.

Results: During the follow-up period, 79 subjects developed CHD. Subjects in the highest quartile had a 5.41-fold (95% confidence interval, 2.12–13.82) higher risk of CHD than those in the lowest quartile after controlling for confounders. In the analysis classifying the participants into four groups according to the levels of serum sdLDL cholesterol and serum low-density lipoprotein (LDL) cholesterol levels, the risk of CHD almost doubled in subjects with sdLDL cholesterol of ≥ 32.9 mg/dL (median), regardless of serum LDL cholesterol levels, as compared with subjects with serum sdLDL cholesterol of < 32.9 mg/dL and serum LDL cholesterol of < 120.1 mg/dL (median). When serum sdLDL cholesterol levels were incorporated into a model with known cardiovascular risk factors, c-statistics was significantly increased (from 0.77 to 0.79; p = 0.02), and the net reclassification improvement was also significant (0.40; p < 0.001).

Conclusions: The present findings suggest that the serum sdLDL cholesterol level is a relevant biomarker for the future development of CHD that offers benefit beyond the serum LDL cholesterol level and a possible therapeutic target to reduce the burden of CHD in a Japanese community.

Serum Lipopolysaccharide-Binding Protein Levels and the Incidence of Cardiovascular Disease in a General Japanese Population: The Hisayama Study

Background

Epidemiological studies have reported a link between serum LBP (lipopolysaccharide‐binding protein) levels and lifestyle‐related diseases. However, there have been no longitudinal studies investigating the association of serum LBP levels and the incidence of cardiovascular disease (CVD) in general populations.

Methods and Results

A total of 2568 community‐dwelling Japanese individuals 40 years and older without prior CVD were followed for 10 years (2002–2012). Serum LBP levels were divided into quartiles (quartile 1: 2.20–9.68 μg/mL; quartile 2: 9.69–10.93 μg/mL; quartile 3: 10.94–12.40 μg/mL; quartile 4: 12.41–24.34 μg/mL). The hazard ratios (HRs) and their 95% CIs for the incidence of CVD were computed using a Cox proportional hazards model. During the follow‐up period, 180 individuals developed CVD. The age‐ and sex‐adjusted cumulative incidence of CVD increased significantly with higher serum LBP levels (P for trend=0.005). Individuals with higher serum LBP levels had a significantly greater risk of the development of CVD after adjusting for conventional cardiovascular risk factors (quartile 1: HR, 1.00 [reference]; quartile 2: HR, 1.04 [95% CI, 0.60–1.78]; quartile 3: HR, 1.52 [95% CI, 0.92–2.51]; and quartile 4: HR, 1.90 [95% CI, 1.17–3.09]; P for trend=0.01). This association remained significant after additional adjustment for homeostasis model assessment of insulin resistance (P for trend=0.01). However, when additional adjustment was made for high‐sensitivity C‐reactive protein, the association was attenuated to the nonsignificant level (P for trend=0.08).

Conclusions

The present findings suggest that higher serum LBP levels are associated with increased risk of the development of CVD in the general Japanese population. Low‐grade endotoxemia may contribute to the pathogenesis of CVD through chronic systemic inflammation.

Population Pharmacokinetic and Exposure-Response Analysis of Finerenone: Insights Based on Phase IIb Data and Simulations to Support Dose Selection for Pivotal Trials in Type 2 Diabetes with Chronic Kidney Disease

BACKGROUND

Finerenone (BAY 94-8862) is a potent non-steroidal, selective mineralocorticoid receptor antagonist being developed for the treatment of patients with type 2 diabetes and chronic kidney disease.

METHODS

We present the population pharmacokinetics and pharmacodynamics (PD) analysis for efficacy and safety markers based on data from two clinical phase IIb studies: ARTS-DN (NCT01874431) and ARTS-DN Japan (NCT01968668).

RESULTS

The pharmacokinetics of finerenone were adequately characterized, with estimated glomerular filtration rate (eGFR) and body weight as influencing covariates. The area under the plasma concentration-time curve in Japanese patients did not differ from that in the global population, and the investigated pharmacokinetics were dose- and time-linear. In addition, the pharmacokinetic model provided robust individual exposure estimates to study exposure-response. The concentration-effect relationship over time for the efficacy marker urinary albumin:creatinine ratio (UACR) was well-characterized by a maximum effect model indicating saturation at high exposures. For the safety markers, a log-linear model and a power model were identified for serum potassium concentration and eGFR, respectively, indicating attenuation of effect gains at high exposures. There was no apparent ethnic effect on the investigated pharmacokinetic-pharmacodynamic relationships. The model-predicted times to reach the full (99%) steady-state drug effect on UACR, serum potassium, and eGFR were 138, 20, and 85 days, respectively, while the pharmacokinetic half-life was 2-3 h and steady state was achieved after 2 days, indicating timescale separation.

CONCLUSION

Our dose-exposure-response modeling and simulation indicates effects were largely saturated at finerenone 20 mg and doses of both 10 and 20 mg once daily appear safe and efficacious at reducing albuminuria.

Undiagnosed and untreated chronic kidney disease and its impact on renal outcomes in the Japanese middle-aged general population

Background

The effectiveness of identifying and monitoring early-stage chronic kidney disease (CKD) is not fully recognised. This study quantified people with undiagnosed CKD among the middle-aged Japanese population and clarified potential risks of untreated CKD.

Methods

We included 71 233 individuals who underwent annual health check-ups (AHC) in 2014 for both baseline and follow-up proteinuria and serum creatine measurements. CKD was identified by AHC data as proteinuria or estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2. We differentiated undiagnosed from diagnosed CKD using the medical claims database. In undiagnosed CKD, we assessed risk differences for disease progression, defined as an eGFR decline slope >3 mL/min/1.73 m2/year or proteinuria incidence over 3 years, between those who visited a physician for CKD treatment within 6 months after AHC and those who did not.

Results

CKD prevalence was 5.7% (5.2% undiagnosed and 0.5% diagnosed). Only 2.1% of the patients with undiagnosed CKD visited a physician for CKD treatment within 6 months after AHC. Between-group risk differences in instrumental variable adjustment models showed that those left untreated progressed to kidney diseases 16.3% more often than those who visited physicians for CKD treatment.

Conclusion

CKD was undiagnosed in 5.2% of the middle-aged general population. Only a few people visited physicians for CKD treatment. Visiting physicians for CKD treatment during the first 6 months after screening may be associated with a lower risk of kidney disease progression.