Prehypertension increases the risk for renal arteriosclerosis in autopsies: the Hisayama Study

Deep Learning-Based Vascular Aging Prediction From Retinal Fundus Images

Purpose

The purpose of this study was to establish and validate a deep learning model to screen vascular aging using retinal fundus images. Although vascular aging is considered a novel cardiovascular risk factor, the assessment methods are currently limited and often only available in developed regions.

Methods

We used 8865 retinal fundus images and clinical parameters of 4376 patients from two independent datasets for training a deep learning algorithm. The gold standard for vascular aging was defined as a pulse wave velocity ≥1400 cm/s. The probability of the presence of vascular aging was defined as deep learning retinal vascular aging score, the Reti-aging score. We compared the performance of the deep learning model and clinical parameters by calculating the area under the receiver operating characteristics curve (AUC). We recruited clinical specialists, including ophthalmologists and geriatricians, to assess vascular aging in patients using retinal fundus images, aiming to compare the diagnostic performance between deep learning models and clinical specialists. Finally, the potential of Reti-aging score for identifying new-onset hypertension (NH) and new-onset carotid artery plaque (NCP) in the subsequent three years was examined.

Results

The Reti-aging score model achieved an AUC of 0.826 (95% confidence interval [CI] = 0.793-0.855) and 0.779 (95% CI = 0.765-0.794) in the internal and external dataset. It showed better performance in predicting vascular aging compared with the prediction with clinical parameters. The average accuracy of ophthalmologists (66.3%) was lower than that of the Reti-aging score model, whereas geriatricians were unable to make predictions based on retinal fundus images. The Reti-aging score was associated with the risk of NH and NCP (P < 0.05).

Conclusions

The Reti-aging score model might serve as a novel method to predict vascular aging through analysis of retinal fundus images. Reti-aging score provides a novel indicator to predict new-onset cardiovascular diseases.

Translational Relevance

Given the robust performance of our model, it provides a new and reliable method for screening vascular aging, especially in undeveloped areas.

Effects of age and axial length on choroidal stratified structure in normal eyes

To quantify the choroidal structures of normal eyes by optical coherence tomography (OCT)-based binarization and evaluate the relationships among age, refractive power, and ocular axial length. This was a retrospective observational study. One hundred and eighty nine eyes of 189 subjects without ocular diseases were examined by enhanced depth imaging (EDI)-OCT. A choroidal OCT horizontal image with a width of 1500 μm centered on the fovea was binarized. The lumen, stroma, and total choroidal area in the choriocapillaris (CC), Sattler's layer (SL), and Haller's layer (HL) were measured, and the ratio of the luminal area to total choroidal area (L/C ratio) was calculated. Multiple regression analysis was performed for choroidal parameters in each choroidal layer and for age, refractive power, and ocular axial length. Multiple regression analysis showed that an older age was significantly correlated with a lower choroidal area and the L/C ratio in all choroidal layers (each P < 0.05). A Long axial length was significantly associated with lower SL and HL (P < 0.05), but not with refractive power. In the choroid of normal eyes, age-related decreases in the choroidal area and L/C ratio were associated with all choroidal layers, and elongation of the axial length was associated with thinning of SL and HL.

Colour tone of retinal arterioles imaged with a colour scanning laser ophthalmoscope can be an indicator of systemic arterial stiffness

OBJECTIVE

Colour scanning laser ophthalmoscope (cSLO) offers several advantages, including improved image quality and better visualisation of the retinal structures compared with colour fundus photograph (CFP). This study aimed to identify whether cSLO could be used to predict systemic arterial stiffness.

METHODS AND ANALYSIS

We retrospectively analysed the data of 54 patients with 103 eyes. In addition to blood pressure and blood data, all patients had cardio-ankle vascular index (CAVI) measurements, as well as images of the fundus acquired using cSLO and CFP. We determined the retinal artery sclerosis (RAS) index from the colour of the retinal artery in cSLO images, the ratio of arterial to venous diameter (A/V ratio), and Scheie's classification in CFP images. The correlation between each parameter and CAVI was examined using Spearman's rank correlation coefficient, and the correlation between Scheie's classification and CAVI was examined using Steel-Dowass tests.

RESULTS

CAVI showed a significant positive correlation with the RAS index (r=0.679, p<0.001) but not with the A/V ratio or Scheie's classification. Multiple regression analysis showed that the RAS index was significantly and independently correlated with CAVI.

CONCLUSION

cSLO is a non-invasive imaging modality that has the potential to accurately and instantaneously detect early systemic arterial stiffness.

Day-to-Day Blood Pressure Variability and Risk of Incident Chronic Kidney Disease in a General Japanese Population

Background Several longitudinal studies have reported that higher visit-to-visit blood pressure variability is associated with greater risk for developing chronic kidney disease. However, no population-based studies have investigated the association between day-to-day home blood pressure variability and incident chronic kidney disease. Methods and Results A total of 2342 Japanese community-dwelling residents aged ≥40 years without chronic kidney disease at baseline were followed up by annual health examinations for 10 years. Home blood pressure was measured 3 times every morning for 28 days. Day-to-day coefficients of variation of home systolic blood pressure levels were categorized into quintiles. Chronic kidney disease was defined as an estimated glomerular filtration rate <60 mL/min per 1.73 m² or the presence of proteinuria. The hazard ratios for developing chronic kidney disease were estimated with a Cox proportional hazards model. During the follow-up period, 772 participants developed chronic kidney disease. Increased coefficients of variation of home systolic blood pressure were associated significantly with higher risk of chronic kidney disease after adjusting for confounders (P for trend <0.001): Individuals in the highest quintile of coefficients of variation had a 1.50-fold (95% CI, 1.17-1.94) greater risk of developing chronic kidney disease than those in the lowest quintile. The combination of higher coefficients of variation and higher mean value of home systolic blood pressure was associated with the multivariable-adjusted risk of developing chronic kidney disease. Conclusions These findings suggest that increased day-to-day blood pressure variability is a significant risk factor for developing chronic kidney disease in a general Japanese population.

Autopsy study examining non-chronic kidney disease versus chronic kidney disease caused by hypertensive-nephrosclerosis in elderly subjects

BACKGROUND

The aim of this autopsy study was to clarify the differences of renal histopathology between non-chronic kidney disease (CKD) and CKD caused by hypertensive-nephrosclerosis in the elderly and during the aging process.

METHODS

We examined autopsy specimens from 105 elderly patients (53 male subjects; mean age, 86.2 years) including 44 patients with CKD as a result of nephrosclerosis. The analysis was divided into two groups depending on whether they had CKD.

RESULTS

The incidences of arterial intimal thickening (AIT), obsolescent-type global glomerulosclerosis (OB), and interstitial fibrosis and tubular atrophy (IF/TA) were higher in the CKD group than in the non-CKD group (all p < 0.01). These factors were all correlated with each other (AIT vs. OB, r = 0.43; AIT vs. IF/TA, r = 0.25; OB vs. IF/TA, r = 0.53). IF/TA had the strongest association with hypertension and decreased eGFR. In the non-CKD group, the frequency of OB was more than 20% in subjects aged 90 years or older. However, the individuals in the non-CKD group tended to have compensatory glomerular hypertrophy with increasing age and a retained eGFR, while the CKD group was unable to obtain compensatory hypertrophy and had a lower eGFR. We also found that AIT, OB and IF/TA occurred independently of systemic atherosclerosis.

CONCLUSIONS

Non-CKD in the elderly refers to the so-called aging kidney. The progression from aging kidney to CKD caused by nephrosclerosis was influenced by increases in AIT, OB and IF/TA. IF/TA was thought to be the most important downstream factor in the progression of aging kidney to CKD.

Association of urinary angiotensinogen with renal arteriolar remodeling in chronic kidney disease

OBJECTIVE

Renin-angiotensin system (RAS) might be associated with arteriolar remodeling. The present study aimed to explore the hitherto unknown relationship between renal RAS and renal arteriolar remodeling and to elucidate whether altered renal RAS subsequently affects renal function in patients with chronic kidney disease (CKD).

METHODS

In this retrospective study, patients with various CKDs not using RAS inhibitors who underwent renal biopsy were included in cross-sectional and longitudinal analyses. Urinary angiotensinogen (UAGT) levels and wall/lumen ratio (WLR) were determined to evaluate renal RAS and renal arteriolar remodeling, respectively. The association between ln(UAGT) and ln(WLR) was cross-sectionally examined using a liner regression model. Furthermore, the association of ln(UAGT) with subsequent changes in estimated glomerular filtration rate (eGFR) per year were longitudinally examined in the largest subgroup of patients who were diagnosed with IgA nephropathy.

RESULTS

In the overall cohort (n = 54), the median age, blood pressures, eGFR, and WLR were 37 years, 120/73 mmHg, 85 ml/min per 1.73 m2, and 0.93, respectively. Ln(UAGT) was significantly and positively associated with ln(WLR) even after adjusting for classical and nonclassical clinical renal risk factors. In patients with IgA nephropathy, higher ln(UAGT) was associated with higher ln(WLR). Ln(UAGT) also tended to be associated with a greater decline in eGFR per year over a median period of 8.7 years, even after adjusting for potential confounding factors.

CONCLUSION

In patients with CKD, renal RAS might be associated with renal arteriolar remodeling and future decline in eGFR, independent of potential risk factors.

Arteriosclerosis, atherosclerosis, arteriolosclerosis, and Monckeberg medial calcific sclerosis: what is the difference?

Cardiovascular diseases are the main cause of death in contemporary times. Arteriosclerosis, atherosclerosis, arteriolosclerosis, and Monckeberg's arteriosclerosis are terms that are often used interchangeably, but they refer to different vascular pathologies. The objective of this study is to review the concepts of atherosclerosis, atherosclerosis, arteriosclerosis and Monckeberg medial calcific sclerosis (MMCS). The term arteriosclerosis is more generic, meaning the stiffening and consequent loss of elasticity of the arterial wall, and encompasses the other terms. Atherosclerosis is an inflammatory disease secondary to lesions in the intimal layer and whose main complication is acute and chronic obstruction of the arterial lumen. Arteriolosclerosis refers to thickening of arterioles, particularly in association with systemic arterial hypertension. MMCS refers to non-obstructive calcification in the internal elastic lamina or the tunica media of muscular arteries. Vascular calcifications, which include atherosclerotic lesions and MMCS, have been studied as a risk factor for cardiovascular morbidity and mortality.

Renal arteriolar hyalinosis, not intimal thickening in large arteries, is associated with cardiovascular events in people with biopsy-proven diabetic nephropathy

AIMS

Diabetic nephropathy, a pathologically diagnosed microvascular complication of diabetes, is a strong risk factor for cardiovascular events, which mainly involve arteries larger than those affected in diabetic nephropathy. However, the association between diabetic nephropathy pathological findings and cardiovascular events has not been well studied. We aimed to investigate whether the pathological findings in diabetic nephropathy are closely associated with cardiovascular event development.

METHODS

This retrospective cohort study analysed 377 people with type 2 diabetes and biopsy-proven diabetic nephropathy, with a median follow-up of 5.9 years (interquartile range 2.0 to 13.5). We investigated how cardiovascular events were impacted by two vascular diabetic nephropathy lesions, namely arteriolar hyalinosis and arterial intimal thickening, and by glomerular and interstitial lesions.

RESULTS

Of the 377 people with diabetic nephropathy, 331 (88%) and 295 (78%) had arteriolar hyalinosis and arterial intimal thickening, respectively. During the entire follow-up period, those with arteriolar hyalinosis had higher cardiovascular event rates in the crude Kaplan-Meier analysis than those without these lesions (P = 0.005, log-rank test). When fully adjusted for clinically relevant confounders, arteriolar hyalinosis independently predicted cardiovascular events [hazard ratio (HR) 1.99; 95% confidence interval (CI) 1.12, 3.86], but we did not find any relationship between arterial intimal thickening and cardiovascular events (HR 0.89; 95% CI 0.60, 1.37). Additionally, neither glomerular nor interstitial lesions were independently associated with cardiovascular events in the fully adjusted model.

CONCLUSIONS

Arteriolar hyalinosis, but not intimal thickening of large arteries, was strongly associated with cardiovascular events in people with diabetic nephropathy.

High-normal blood pressure and related cardiovascular risk factors prevalence in the Romanian adult population: insights from the SEPHAR III study

High normal blood pressure (HNBP) is associated with an increased risk of incident high blood pressure (HBP) and of cardiovascular diseases (CVD). To estimate the prevalence of HNBP and related cardiovascular risk factors, a representative sample of 1970 Romanian adults was enrolled in SEPHAR III survey (Study for the Evaluation of Prevalence of Hypertension and Cardiovascular Risk in Romania). All were evaluated for blood pressure values and by a 71-item questionnaire, anthropometric measurements, together with extensive evaluation for target organ damage, blood, and urine sample collection. Prevalence of HNBP was 11% [45.1% had HBP, 43.9% normal BP (NBP)]. HNBP individuals were older (51.14 ± 17.13 years) than subjects with NBP (40.5 ± 15.96 years) but younger than those with HBP (55.79 ± 15.68 years), p < 0.0001 (95% CI 18-85, respectively 18-91). Values of weight, waist circumference, body mass index, total and LDL cholesterol, triglycerides, fasting blood glucose, glycosylated hemoglobin (HbA1c), uric acid, serum creatinine, glomerular filtration rate estimate by CKD-EPI equation, urinary albumin to creatinine ratio, intimae-media thickness, arterial stiffness measurements and diastolic dysfunction, indexed left ventricular mass, interventricular septum and posterior left ventricle wall thickness, left atrial volume, and LA dilatation were significantly higher in HNBP subjects than in NBP. Our study showed that individuals with HNBP represent ~11% and most of them had an elevated total cardiovascular risk. It is essential to educate the public and health care providers to be aware of these individuals and of steps that should be taken to treat modifiable cardiovascular risk factors.

Association of renal arteriosclerosis and hypertension with renal and cardiovascular outcomes in Japanese type 2 diabetes patients with diabetic nephropathy

AIMS/INTRODUCTION

The present retrospective study investigated the impact of renal arteriosclerosis (AS) and hypertension (HT) on long-term renal and cardiovascular outcomes in Japanese type 2 diabetes patients with biopsy-proven diabetic nephropathy.

MATERIALS AND METHODS

A total of 185 patients were enrolled. Patients were divided into four groups stratified by renal AS status and the presence of HT. The outcomes for this study were the first occurrence of renal events (a need for dialysis or a 30% decline in estimated glomerular filtration rate from baseline) and cardiovascular events (cardiovascular death, non-fatal myocardial infarction, coronary intervention or non-fatal stroke).

RESULTS

The proportion of renal AS scores ≥1 was 88.3% among patients with normal-range blood pressure (BP) and 95.4% among patients with HT. During a mean follow-up period of 7.6 years, 129 episodes of renal composite events and 55 episodes of cardiovascular events were observed. Compared with patients with no renal AS and normal-range BP, a renal AS score ≥1 increased the risk of renal composite events with a multivariable-adjusted hazard ratio of 3.21 (95% confidence interval [95% CI] 1.27-8.14) in patients with normal-range BP and 4.99 (95% CI 1.98-12.54) in patients with HT, whereas renal AS score ≥1 increased the risk of cardiovascular events with a multivariable-adjusted hazard ratio of 6.06 (95% CI 1.24-29.61) in patients with normal-range BP and 10.02 (95% CI 1.92-52.39) in patients with HT.

CONCLUSIONS

Renal AS was associated with increasing risks for renal composite events and cardiovascular events in both normal-range BP and HT. The risks of renal composite events and cardiovascular events were the highest in both renal AS and HT.

BP Reduction, Kidney Function Decline, and Cardiovascular Events in Patients without CKD

BACKGROUND AND OBJECTIVES

In the Systolic Blood Pressure Intervention Trial (SPRINT), intensive systolic BP treatment (target <120 mm Hg) was associated with fewer cardiovascular events and higher incidence of kidney function decline compared with standard treatment (target <140 mm Hg). We evaluated the association between mean arterial pressure reduction, kidney function decline, and cardiovascular events in patients without CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We categorized patients in the intensive treatment group of the SPRINT according to mean arterial pressure reduction throughout follow-up: <20, 20 to <40, and ≥40 mm Hg. We defined the primary outcome as kidney function decline (≥30% reduction in eGFR to <60 ml/min per 1.73 m2 on two consecutive determinations at 3-month intervals), and we defined the secondary outcome as cardiovascular events. In a propensity score analysis, patients in each mean arterial pressure reduction category from the intensive treatment group were matched with patients from the standard treatment group to calculate the number needed to treat regarding cardiovascular events and the number needed to harm regarding kidney function decline.

RESULTS

In the intensive treatment group, 1138 (34%) patients attained mean arterial pressure reduction <20 mm Hg, 1857 (56%) attained 20 to <40 mm Hg, and 309 (9%) attained ≥40 mm Hg. Adjusted hazard ratios for kidney function decline were 2.10 (95% confidence interval, 1.22 to 3.59) for mean arterial pressure reduction between 20 and 40 mm Hg and 6.22 (95% confidence interval, 2.75 to 14.08) for mean arterial pressure reduction ≥40 mm Hg. In propensity score analysis, mean arterial pressure reduction <20 mm Hg presented a number needed to treat of 44 and a number needed to harm of 65, reduction between 20 and <40 mm Hg presented a number needed to treat of 42 and a number needed to harm of 35, and reduction ≥40 mm Hg presented a number needed to treat of 95 and a number needed to harm of 16.

CONCLUSIONS

In the intensive treatment group of SPRINT, larger declines in mean arterial pressure were associated with higher incidence of kidney function decline. Intensive treatment seemed to be less favorable when a larger reduction in mean arterial pressure was needed to attain the BP target.

Association between serum uric acid level and renal arteriolar hyalinization in individuals without chronic kidney disease

BACKGROUND AND AIMS

Recent studies have reported an association between serum uric acid (SUA) and renal arteriolar changes in patients with chronic kidney disease (CKD). However, the association in individuals without CKD remains unclear. In this study, we investigated the relationship between SUA and renal arteriolar lesions in individuals without CKD from our living kidney donor cohort.

METHODS

Between January 2006 and May 2016, 393 living kidney donors underwent "time-zero" biopsy at Kyushu University Hospital. Patients were divided into sex-specific quartiles of SUA before donation: Q1, Q2, Q3, and Q4 (male: <5.2,5.2-5.8,5.9-6.4, and ≥6.5 mg/dL, female: <3.8,3.8-4.3,4.4-5.0, and ≥5.1 mg/dL). Renal arteriolar hyalinization and wall thickening were assessed using a semiquantitative grading system. Predictive performance was compared between models with and without SUA by calculating the net reclassification improvement (NRI).

RESULTS

In total, 158 (40.2%) patients had arteriolar hyalinization, and 148 (37.6%) had wall thickening. High SUA was significantly associated with arteriolar hyalinization in multivariable logistic analysis (odds ratio [OR] per 1-mg/dL increase in SUA, 1.24; 95% confidence interval [CI], 1.00-1.53; p = 0.048. OR for Q4 vs. Q2, 2.22; 95% CI, 1.17-4.21; p = 0.01). We found no association between SUA and wall thickening. When SUA was incorporated into a predictive model with conventional atherosclerotic factors, the NRI was 0.21 (p = 0.04).

CONCLUSIONS

High SUA was an independent risk factor for arteriolar hyalinization in individuals without CKD. SUA provided additional predictive value beyond conventional atherosclerotic factors in predicting arteriolar hyalinization.

Association between G-protein β3 subunit gene and isolated systolic blood pressure elevation of greater than 130 mmHg: A large-scale cross-sectional study in the Japanese population

AIM

To investigate whether GNB3 C825T single nucleotide polymorphism (SNP) contributes to systolic blood pressure (SBP) ≥ 130 mmHg in a large-scale cross-sectional study among the Japanese population with diastolic blood pressure (DBP) < 85 mmHg.

METHODS

We analyzed 11008 Japanese subjects, including 2797 cases (SBP ≥ 130 and DBP < 85 mmHg) who were not taking anti-hypertensive medication and 8211 controls (SBP < 130 and DBP < 85 mmHg), all of whom enrolled in the genome banking project of the 21^st Century COE (Center of Excellence) Program at Jichi Medical University. Subjects were divided into four groups according to gender (male and female) and age (≤ 49 years and ≥ 50 years). GNB3 gene polymorphism was determined using the TaqMan probe method. We compared the frequencies of alleles and genotypes between cases and controls by chi-squared test. The strength of the associations was estimated by odds ratios (ORs) and 95%CI by using logistic regression analysis. The ORs were adjusted for age and body mass index.

RESULTS

Allele and genotype distributions significantly differed between cases and controls only in males aged ≤ 49 years. Compared to the CC genotype, a significant OR was obtained in the TT genotype among males aged ≤ 49 years.

CONCLUSION

This study indicates that the TT genotype of the GNB3 C825T SNP may contribute to SBP elevation of greater than 130 mmHg compared to the CC genotype in Japanese males aged ≤ 49 years.

Age-Related Renal Microvascular Changes: Evaluation by Three-Dimensional Digital Imaging of the Human Renal Microcirculation Using Virtual Microscopy

The renal microvasculature is targeted during aging, sometimes producing chronic kidney disease (CKD). Overdiagnosis of CKD in older persons is concerning. To prevent it, a new concept of “healthy aging” is arising from a healthy renal donor study. We investigated the renal microcirculatory changes of three older persons and compared them with that of one patient with nephrosclerosis using a three-dimensional (3D) reconstruction technique that we previously developed. This method uses a virtual slide system and paraffin-embedded serial sections of surgical material that was double-immunostained by anti-CD34 and anti-α smooth muscle actin (SMA) antibodies for detecting endothelial cells and medial smooth muscle cells, respectively. In all cases, the 3D images proved that arteriosclerotic changes in large proximal interlobular arteries did not directly induce distal arterial change or glomerulosclerosis. The nephrosclerotic patient showed severe hyalinosis with luminal narrowing of small arteries directly inducing glomerulosclerosis. We also visualized an atubular glomerulus and intraglomerular dilatation of an afferent arteriole during healthy aging on the 3D image and showed that microcirculatory changes were responsible for them. Thus, we successfully visualized healthy aged kidneys on 3D images and confirmed the underlying pathology. This method has the ability to investigate renal microcirculatory damage during healthy aging.

Detection and Clinical Patterns of Nephron Hypertrophy and Nephrosclerosis Among Apparently Healthy Adults

BACKGROUND

Even among ostensibly healthy adults, there is often mild pathology in the kidney. The detection of kidney microstructural variation and pathology by imaging and the clinical pattern associated with these structural findings is unclear.

STUDY DESIGN

Cross-sectional (clinical-pathologic correlation).

SETTING & PARTICIPANTS

Living kidney donors at Mayo Clinic (Minnesota and Arizona sites) and Cleveland Clinic 2000 to 2011.

PREDICTORS

Predonation kidney function, risk factors, and contrast computed tomographic scan of the kidneys. These scans were segmented for cortical volume and medullary volume, reviewed for parenchymal cysts, and scored for kidney surface roughness.

OUTCOMES

Nephrosclerosis (glomerulosclerosis, interstitial fibrosis/tubular atrophy, and arteriosclerosis) and nephron size (glomerular volume, mean profile tubular area, and cortical volume per glomerulus) determined from an implantation biopsy of the kidney cortex at donation.

RESULTS

Among 1,520 living kidney donors, nephrosclerosis associated with increased kidney surface roughness, cysts, and smaller cortical to medullary volume ratio. Larger nephron size (nephron hypertrophy) associated with larger cortical volume. Nephron hypertrophy and larger cortical volume associated with higher systolic blood pressure, glomerular filtration rate, and urine albumin excretion; larger body mass index; higher serum uric acid level; and family history of end-stage renal disease. Both nephron hypertrophy and nephrosclerosis associated with older age and mild hypertension. The net effect of both nephron hypertrophy and nephrosclerosis associating with cortical volume was that nephron hypertrophy diminished volume loss with age-related nephrosclerosis and fully negated volume loss with mild hypertension-related nephrosclerosis.

LIMITATIONS

Kidney donors are selected on health, restricting the spectrum of pathologic findings. Kidney biopsies in living donors are a small tissue sample leading to imprecise estimates of structural findings.

CONCLUSIONS

Among apparently healthy adults, the microstructural findings of nephron hypertrophy and nephrosclerosis differ in their associations with kidney function, macrostructure, and risk factors.

Prehypertension and Chronic Kidney Disease in Chinese Population: Four-Year Follow-Up Study

Hypertension is a well established cause of chronic kidney disease (CKD). However, the effect of prehypertension on risk of CKD is controversial. The aim of this study is to determine whether prehypertension increases the risk of CKD events in the Chinese population. We enrolled 20,034 with prehypertension and 12,351 with ideal blood pressure in this prospective study. CKD was defined as an estimated glomerular filtration rate (eGFR) <60 ml/min 1.73 m2. The new occurrences of CKD events were collected during follow-up. Cumulative survival and freedom for the occurrence of new CKD events was analyzed using the Kaplan-Meier approach. Multivariate Cox Regression was used to analyze the effect of prehypertension on CKD. The median follow-up time was 47 (interquartile range 44-51) months. 601 new onset CKD events occurred during the follow-up period. The cumulative incidence of new CKD events was higher in the prehypertensive population than that in the ideal blood pressure population (2.10% vs 1.46%, P = 0.0001). Multivariate Cox Regression showed that relative risks (RRs) for the new onset CKD events in the prehypertensive population were 1.69 (95% confidence intervals (CI): 1.41~2.04, P = 0.001) higher than those in the ideal blood pressure population. Similarly, the risks were 1.68 (95% CI: 1.33~2.13 P = 0.001) times higher in females and 2.14 (95% CI: 1.58~2.91 P = 0.001) times higher in males by adjustment for traditional CV risk factors. Our findings demonstrated prehypertension is an independent risk factor for the occurrence of new CKD events in the Chinese population.

Prehypertension and Incidence of ESRD: a systematic review and meta-analysis

BACKGROUND

Studies of the association of prehypertension with the incidence of end-stage renal disease (ESRD) after adjusting for other cardiovascular risk factors have shown controversial results.

STUDY DESIGN

Systematic review and meta-analysis of prospective cohort studies.

SETTING & POPULATION

Adults with prehypertension.

SELECTION CRITERIA FOR STUDIES

Studies evaluating the association of prehypertension with the incidence of ESRD identified by searches in PubMed, EMBASE, and Cochrane Library databases and conference proceedings, without language restriction.

PREDICTOR

Prehypertension.

OUTCOMES

The relative risks (RRs) of ESRD were calculated and reported with 95% CIs. Subgroup analyses were conducted according to blood pressure (BP), age, sex, ethnicity, and study characteristics.

RESULTS

Data from 1,003,793 participants were derived from 6 prospective cohort studies. Compared with optimal BP, prehypertension significantly increased the risk of ESRD (RR, 1.59; 95% CI, 1.39-1.91). In subgroup analyses, prehypertension significantly predicted higher ESRD risk across age, sex, ethnicity, and study characteristics. Even low-range (BP, 120-129/80-84 mm Hg) prehypertension increased the risk of ESRD compared with optimal BP (RR, 1.44; 95% CI, 1.19-1.74), and the risk increased further with high-range (BP, 130-139/85-89 mm Hg) prehypertension (RR, 2.02; 95% CI, 1.70-2.40). The RR was significantly higher in the high-range compared with the low-range prehypertensive population (P = 0.01).

LIMITATIONS

No access to individual patient-level data.

CONCLUSIONS

Prehypertension is associated with incident ESRD. The increased risk is driven largely by high-range prehypertension.

Impact of lower range of prehypertension on cardiovascular events in a general population: the Hisayama Study

OBJECTIVES

The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC7) defined blood pressure (BP) levels of 120-139/80-89  mmHg as prehypertension. The objective of the present analysis was to examine the impact of prehypertension and its population-attributable fraction for development of cardiovascular events in a general Japanese population.

METHODS

Two thousand, six hundred and thirty-four residents of the town of Hisayama aged at least 40 years without cardiovascular disease were followed up for 19 years. BP categories were defined using JNC7, and prehypertension was divided into the lower (120-129/80-84  mmHg) and higher ranges (130-139/85-89  mmHg). During the follow-up period, 449 participants developed cardiovascular disease (305 strokes and 187 coronary heart diseases).

RESULTS

The frequencies of normal BP, prehypertension, and stages 1 and 2 hypertension were 24.9, 37.7, 23.8, and 13.6%, respectively. The age and sex-adjusted incidence of cardiovascular disease rose progressively with elevation of BP levels (P < 0.001 for trend). The risks of cardiovascular disease in lower and higher ranges of prehypertension were 58% [95% confidence interval (CI) 11-126%] and 70% (95% CI 18-144%) higher than normal BP even after controlling for other cardiovascular risk factors. The population-attributable fraction of prehypertension was 13.2%, which was similar to those of stages 1 and 2 hypertension.

CONCLUSIONS

The risks of cardiovascular disease increased significantly from the lower range of prehypertension in a general Japanese population. Approximately one-third of excess cardiovascular events attributable to elevated BP levels were estimated to occur among individuals with prehypertension.

Pre-hypertension as a significant predictor of chronic kidney disease in a general population: the Ohasama Study

BACKGROUND

Hypertension is associated with an increased risk of development of chronic kidney disease (CKD). However, it is unclear whether pre-hypertension is related to the incidence of CKD.

METHODS

The incidence of CKD defined as positive proteinuria or estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m(2) was examined in 2150 inhabitants without pre-existing CKD from the general Japanese population. The association of blood pressure and CKD incidence was examined using a Cox regression model adjusted for age, sex, habitual smoking and drinking, obesity, history of cardiovascular disease, diabetes mellitus or hypercholesterolemia, eGFR at baseline, number of follow-up examinations and year of baseline examination. Participants were categorized according to the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure.

RESULTS

Participants were categorized into normotension (n = 586, 27.3 % ), pre-hypertension (n = 815, 37.9 % ), Stage 1 hypertension (n = 386, 18.0 % ) and Stage 2 hypertension (n = 363, 16.9 % ). During a mean follow-up of 6.5 years (14 023 person-years), 461 incidences of CKD were recorded. Compared to normotension, adjusted hazard ratios of CKD were significantly higher for pre-hypertension (1.49, P < 0.003), Stage 1 (1.83, P < 0.001) and Stage 2 (2.55, P < 0.001) hypertension. The population-attributable fraction of pre-hypertension (12.1 % ) was considered to be compatible to that of Stage 1 (8.6 % ) and Stage 2 (14.9 % ) hypertension.

CONCLUSION

This was the first study to demonstrate that pre-hypertension was significantly associated with an increased risk of CKD and was one of the considerable causes of CKD in the general population.

Prevalence, risk factors, and management of prehypertension

Prehypertension remains an important public health challenge all over the world and appropriate treatments should be adopted to prehypertensive group in different degree effectively. This review aimed to assess the prevalence of Prehypertension and provide effective evidence of the benefits of treating prehypertensive patients. The reasonable evaluation and appropriate intervention of prehypertensive remain need further study.

Treating prehypertension: medically sound and economically viable

The 7th Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure provided new guide-lines for the definition and management of hypertension. Notably, a new category-"prehypertension"-was created for intermediate systolic pressures exceeding 120 mmHg, the upper limit of normal, but less than 139 mmHg, the threshold for stage 1 hypertension. The therapeutic consequences of this new classification are not yet clear, but research indicates that prehypertension is an independent risk factor for cardiovascular, cognitive, and renal morbidities as well as diabetes, and statistical data indicate that prehypertension is present in over 30% of US, European, and Asian adults. However, while pharmacotherapy is recommended for hypertension, the use of drugs to control prehypertension is under question. Given the serious health consequences linked with prehypertension, such debates seem misplaced if patient well-being is our priority. While acknowledging the lack of specific randomized controlled trial data on this topic, we suggest that anti-hypertensive therapy be recommended for everyone with prehypertension and address resulting cost-benefit issues.

Prehypertension: is it relevant for nephrologists?

Blood pressure (BP) in the prehypertensive range is associated with an increased risk for cardiovascular (CV) disease. Patients with co-morbidities are at greater risk for chronic kidney disease (CKD) development in the presence of prehypertension. Lifestyle changes can alter the natural history of prehypertension; however, long-term adherence is rare and thus, their impact on outcomes is limited. Pharmacological therapy in patients with prehypertension and demonstrable target organ damage with blockers of the renin-angiotensin system has demonstrated benefits on markers of CKD outcomes such as microalbuminuria. There are no data, however, on 'hard end points' such as doubling of creatinine or need for renal replacement therapy. In patients with diabetes, monitoring changes in albuminuria, along with assessment of BP in the prehypertensive range, is important to optimize early management and impact the attenuation of CKD progression. Data from natural history studies in patients with type 1 diabetes indicate that increases within the microalbuminuria range antedate increases in BP within the prehypertensive range. Even within the microalbuminuria range, however, systolic BP increases above 125 mm Hg are predictive of nephropathy. Thus, nephrologists need to ensure that their colleagues appreciate the importance of not only early BP intervention but also of monitoring albuminuria changes in order to have maximal impact on CKD prevention.

Effect of aging on retinal circulation in normotensive healthy subjects

Although it is important to investigate the effects of normal aging on the ocular circulation, few studies have examined the effects of aging on the retinal microcirculation in healthy subjects. The purpose of this study was to evaluate the effects of aging on the retinal microcirculation in healthy men. Forty-five healthy men were divided into three groups based on age (young, middle-aged, elderly). We measured vessel diameter and blood velocity and calculated the retinal blood flow (RBF) and wall shear rate (WSR) in the retinal arteries. We performed pulse wave analysis obtained from the retinal blood velocity measurements. We also divided the subjects into two groups based on the presence or absence of prehypertension defined as 120-139/80-89 mmHg. No significant differences in vessel diameter, blood velocity, RBF, and WSR were seen among the groups. Pulse wave analysis showed significant increases in upstroke time (UT) in elderly men compared with young men (P < 0.05). Multiple regression analysis showed that the UT was correlated with age in all subjects. A significant difference was seen only in the UT between subjects with and without prehypertension. The UT calculated from the retinal blood velocity profile is associated significantly with aging, suggesting that measurement of the UT may detect the changes in the retinal and the systemic vessels with increasing age. The UT is the only parameter that increased significantly in subjects with prehypertension compared with those without prehypertension, suggesting that the UT may indicate the effects of prehypertension on the retinal arterioles.

Treating prehypertension: a review of the evidence

Although the term "prehypertension" has been challenged by some, its use to define people with systolic blood pressure (BP) between 120 and 139 mm Hg and/or diastolic pressures between 80 and 89 mm Hg has gained general acceptance. The category includes as many people as the number who have hypertension, defined as blood pressure of 140/90 or above. Such people are clearly at an increased risk of cardiovascular damage compared with people with BPs below 120/80 mm Hg. The major unresolved issue is the appropriate management of such patients. Two trials have attempted to document the value of short-term drug therapy to prevent the progression of BP to overt hypertension, but no outcome studies are currently available.

Rituximab treatment of collapsing C1q glomerulopathy: clinical and histopathological evolution

A 13-year-old girl with obesity and hyperinsulinism developed steroid-resistant nephrotic syndrome due to collapsing glomerulopathy with dominant C1q-containing mesangial immune deposits (CG/C1qN). She became overtly diabetic while receiving alternate-day prednisone and tacrolimus, requiring insulin injections. Despite the addition of mycophenolate mofetil to the treatment regimen, renal function subsequently declined. Rituximab (four weekly doses of 375 mg/m2) was tried 6 months after initial presentation and 3 months after weaning all glucocorticoids. Glomerular filtration rate (GFR) and proteinuria improved. Unexpectedly, blood sugar control normalized 6 weeks after antibody infusion. Rituximab was readministered 20 months after the first course because of deteriorating renal function, but the effect on GFR and proteinuria was modest. A retrospective analysis revealed that tubulointerstitial infiltrates present in the biopsies prior to treatment with rituximab contained numerous CD20+ and CD3+ (CD4 > CD8) lymphocyte aggregates. Rebiopsy 10 weeks after repeat rituximab therapy demonstrated the elimination of B-cell infiltrates and the apparent decrease of interstitial T-cell infiltrates, yet persistent, advanced global glomerulosclerosis, interstitial fibrosis and tubular atrophy. In conclusion, CG/C1qN was associated with B- and T-cell-rich tubulointerstitial infiltrates. B-cell-directed therapy delayed clinical progression during early disease but failed to prevent or ameliorate chronic changes, despite effective tissue B-cell clearance. The incidental resolution of diabetes was noted after rituximab treatment.