Relationships between renovascular disease, blood pressure, and renal function in the elderly: a population-based study

Abdominal arterial lesions associated with antiphospholipid antibodies: A comparative cross sectional magnetic resonance angiography study

INTRODUCTION

Case reports and small case series suggest that stenotic lesions of the renal, coeliac and mesenteric arteries may occur in the antiphospholipid syndrome (APS) resulting in clinical consequences such as hypertension and abdominal angina.

OBJECTIVE

To determine the prevalence of stenotic lesions in arteries arising from the middle aorta in patients with antiphospholipid antibodies (aPL) compared with healthy, hypertensive and atherosclerotic controls.

PATIENTS AND METHODS

In a cross-sectional comparative radiological study using magnetic resonance angiography (MRA) we assessed 5 groups of subjects for the prevalence of stenotic lesions in arteries arising from the middle aorta: APS/aPL positive, healthy renal donors, patients with hypertension, patients with atherosclerosis defined radiologically and patients with systemic lupus erythematosus and vasculitis who were negative for aPL. All subjects underwent MRA in suspended respiration and images were assessed by 2 senior radiologists blinded to the clinical details.

RESULTS

In the atherosclerosis group, vascular stenotic lesions were more prevalent (71%) than in any other group (p≤ 0.000002). The prevalence of all stenotic lesions in aPL positive patients (33%) was significantly higher than in the renal donors (18%) and hypertensive patients (19%) (p≤ 0.009). Renal artery stenosis was significantly more prevalent in aPL positive patients than in renal donors (p≤ 0.0006) but similar to the prevalence in hypertensive patients. Coeliac and/or mesenteric lesions were significantly more common in aPL positive patients vs hypertensive patients (p≤ 0.001). Stenoses did not correlate with traditional risk factors.

CONCLUSION

Arterial stenotic lesions in arteries arising from the middle aorta were highly prevalent in atherosclerotic subjects and were more common in aPL positive patients than hypertensive patients and healthy renal donors.

Current trends of major arterial diseases in Korea: based on data from the Health Insurance Review and Assessment Service

Purpose

This study aims to figure out the changes of the prevalence and management of carotid arterial occlusive diseases (CAOD), abdominal aortic diseases (AAA), and arterial diseases of the lower extremities (LAOD) in Korea over the past 5 years.

Methods

Data were extracted from the Health Insurance Review and Assessment Service during the period from 2008 to 2012.

Results

The number of patients with CAOD increased by about 30% every year. From the year 2008, the number of open surgeries (OS) and endovascular treatments (ET) increased by more than 20% during each of the first 2 years and by 10% every year for 3 years thereafter for CAOD. ET was preferred to OS and occupied 77%–79% of the total number of procedures. The number of patients with AAA increased by 11%–17% every year. ET for AAA occupied 52% of the total number of procedures in 2008 and gradually increased to 70% in 2012. The number of patients who were diagnosed with LAOD fluctuated over the five years. The total number of procedures to treat LAOD increased each year by 20%–25%. ET for LAOD constantly increased by 18%–24% each year and occupied 80%–95% of the total number of procedures.

Conclusion

It is evident that the incidence of vascular diseases will be increasing as our society ages, not to mention its care costs. The need for long-range plans and guidelines are urgent.

Resistive index as a predictor of acute kidney injury caused by an angiotensin converting enzyme inhibitor or angiotensin II receptor blocker in chronic kidney disease patients

Background

Angiotensin converting enzyme (ACE) inhibitor and angiotensin receptor blocker (ARB) may induce acute kidney injury (AKI). The aim of this study was to evaluate the role of the resistive index (RI), which reflects renal artery resistance on renal duplex ultrasonography, as a predictor of AKI in chronic kidney disease (CKD) patients who are prescribed an ACE inhibitor or ARB.

Methods

We screened 105 CKD patients evaluated with renal duplex ultrasonography from 2008 to 2012. We excluded patients not treated with ACE inhibitor or ARB and diagnosed with renal artery stenosis. Finally, we retrospectively analyzed the medical records of 54 patients. AKI was defined as increased serum creatinine by >30% compared with baseline after starting ACE inhibitor or ARB treatment.

Results

The mean age of the patients was 60.5±13.0 years, serum creatinine level was 1.85±0.85 mg/dL and 22.2% of the patients had AKI after the use of an ACE inhibitor or ARB. The RI (P=0.006) and the percentages of patients with diabetes (P=0.008) and using diuretics (P=0.046) were higher in the AKI group. The area under the receiver operating characteristics curve for the prediction of AKI was 0.736 (95% confidence interval=0.587–0.885, P=0.013), and RI≥0.80 predicted AKI with 83.3% sensitivity and 61.9% specificity. In the multivariate analysis, RI≥0.80 was an independent prognostic factor [Exp (B)=8.03, 95% confidence interval=1.14–56.74, P=0.037] for AKI.

Conclusion

RI≥0.80 on the renal duplex ultrasonography may be a helpful predictor for AKI in CKD patients who are prescribed an ACE inhibitor or ARB.

Associations between renal duplex parameters and adverse cardiovascular events in the elderly: a prospective cohort study

BACKGROUND

Atherosclerotic renovascular disease is associated with an increased risk of cardiovascular disease (CVD) events. This study examines associations between Doppler-derived parameters from the renal artery and renal parenchyma and all-cause mortality and fatal and nonfatal CVD events in a cohort of elderly Americans.

STUDY DESIGN

Cohort study.

SETTING

A subset of participants from the Cardiovascular Health Study (CHS). Through an ancillary study, 870 (70% recruitment) Forsyth County, NC, CHS participants consented to undergo renal duplex sonography to define the prevalence of renovascular disease in the elderly, resulting in 726 (36% men; mean age, 77 years) technically adequate complete studies included in this investigation.

PREDICTOR

Renal duplex sonography-derived Doppler signals from the main renal arteries and renal parenchyma. Spectral analysis from Doppler-shifted frequencies and angle of insonation were used to estimate renal artery peak systolic and end diastolic velocity (both in meters per second). Color Doppler was used to identify the corticomedullary junction. Using a 3-mm Doppler sample, the parenchymal peak systolic and end diastolic frequency shift (both in kilohertz) were obtained. Resistive index was calculated as (1 - [end diastolic frequency shift/peak systolic frequency shift]) using Doppler samples from the hilar arteries of the left or right kidney with the higher main renal artery peak systolic velocity.

OUTCOMES & MEASUREMENTS

Proportional hazard regression analysis was used to determine associations between renal duplex sonography-derived Doppler signals and CVD events and all-cause mortality adjusted for accepted cardiovascular risk factors. Index CVD outcomes were defined as coronary events (angina, myocardial infarction, and coronary artery bypass grafting/percutaneous coronary intervention), cerebrovascular events (stroke or transient ischemic attack), and any CVD event (angina, congestive heart failure, myocardial infarction, stroke, transient ischemic attack, and coronary artery bypass grafting [CABG]/percutaneous transluminal coronary intervention [PTCI]).

RESULTS

During follow-up, 221 deaths (31%), 229 CVD events (32%), 122 coronary events (17%), and 92 cerebrovascular events (13%) were observed. Renal duplex sonography-derived Doppler signals from the renal parenchyma were associated independently with all-cause mortality and CVD outcomes. In particular, increased parenchymal end diastolic frequency shift was associated significantly with any CVD event (HR, 0.73; 95% CI, 0.62-0.87; P < 0.001). Marginally significant associations were observed between increases in parenchymal end diastolic frequency shift and decreased risk of death (HR, 0.86; 95% CI, 0.73-1.00; P = 0.06) and decreased risk of cerebrovascular events (HR, 0.78; 95% CI, 0.61-1.01; P = 0.06). Parenchymal end diastolic frequency shift was not significantly predictive of coronary events (HR, 0.84; 95% CI, 0.67-1.06; P = 0.1).

LIMITATIONS

CHS participants showed a "healthy cohort" effect that may underestimate the rate of CVD events in the general population.

CONCLUSION

Renal duplex sonographic Doppler signals from the renal parenchyma showed significant associations with subsequent CVD events after controlling for other significant risk factors. In particular, a standard deviation increase in parenchymal end diastolic frequency shift was associated with 27% risk reduction in any CVD event.

Atherosclerotic renovascular disease among hypertensive adults

PURPOSE

This report describes the change in atherosclerotic renovascular disease (AS-RVD) among hypertensive adults referred for renal duplex sonography (RDS) scan.

METHODS

From Oct 1993 through July 2008, 20,994 patients had RDS at our center. A total of 434 hypertensive patients with two or more RDS exams without intervention comprised the study cohort. Patient demographics (blood pressures, medications, serum creatinine levels, and data from RDS) were collected. Analyses of longitudinal changes in Doppler scan parameters, blood pressures, and renal function were performed by fitting linear growth-curve models. After confirming the linearity of change in Doppler scan parameters among patients with variable number of studies, estimates of mean slopes were calculated using maximum likelihood techniques. For changes in renal function, quadratic growth curves were required to describe longitudinal change.

RESULTS

A total of 434 subjects (212 men [49%] and 222 women [51%]; mean age, 64.6 +/- 12.2 years) provided 1351 studies (mean, 3.2 +/- 2.4; range, 2 to 18) for 863 kidneys over a mean follow-up of 34.4 +/- 25.1 months. At baseline, 20.6% of kidneys demonstrated hemodynamically significant stenosis. On follow-up, 72 kidneys (9.1%) demonstrated anatomic progression of disease. A total of 54 kidneys (6.9%) progressed to significant stenosis and 18 (2.3%) progressed to occlusion. Controlling for progression of disease, baseline renal artery status demonstrated a strong association with baseline kidney length (P = .0006). Significant annualized change in renal length was observed (cm change/year +/- standard error of the mean [SEM]: 0.042 +/- 0.011; P = .0002) among both kidneys with and without critical disease at baseline, however, decline in length was significantly greater among kidneys exhibiting progression of renovascular disease (-0.152 +/- 0.028 cm/year; comparison of slopes between groups P = .0005). In the absence of progression, the presence or absence of critical renal artery stenosis at baseline did not affect the rate of decline in renal length. Fitted models for the natural log transform of serum creatinine demonstrated a significant increase during follow-up (P < .0001). No association was observed between change in serum creatinine and baseline renovascular disease status, or its progression.

CONCLUSION

A total of 32% of hypertensive adults referred for RDS demonstrated hemodynamically significant renal artery stenosis. Regardless of the presence or absence of baseline disease, a small percentage of patients demonstrated anatomic progression of AS-RVD. A total of 9.1% demonstrated anatomic progression and 2.3% progressed to occlusion. Although anatomic progression of AS-RVD was associated with an increased rate of decline in renal length, progression did not predict a decline in excretory renal function. Intervention for AS-RVD should be selective and reserved for strict indications.

Associations of periodontal damage and tooth loss with atherogenic factors among patients with type 2 diabetes mellitus

OBJECTIVE

To clarify the associations of periodontal damage and tooth loss with atherogenic factors among diabetic patients.

METHODS

We examined the correlations of age, sex, smoking, oral hygiene score, blood pressure, body mass index, and blood chemical data with the mean depth of periodontal pockets or the number of remaining teeth.

PATIENTS

One hundred outpatients with type 2 diabetes aged 29 to 77 years.

RESULTS

The mean depth of periodontal pockets was significantly associated with smoking, oral hygiene score, and HbA1c; the Spearman correlation coefficients (r) were 0.220, 0.417, and 0.260, respectively. Age, oral hygiene score, and HbA1c were inversely correlated with the number of remaining teeth (r=-0.306, -0.287, and -0.275, respectively). Serum total cholesterol was significantly correlated with the mean depth of pockets after adjustment for smoking, oral hygiene score, and HbA1c (r=0.211; P=0.044), while serum HDL cholesterol tended to be negatively associated with depth (r=-0.202; P=0.055). Serum HDL cholesterol was also associated with an increased number of teeth, which remained significant after adjustment for age, oral hygiene score, and HbA1c (r=0.202; P=0.048). The estimated glomerular filtration rate was significantly and positively correlated with the number of teeth in the univariate analysis, although consideration of the potential confounding factors somewhat weakened the association (r=0.186; P=0.069).

CONCLUSIONS

We may expect better management of oral health in diabetic patients with control of dyslipidemia in addition to blood glucose.

Progression of atherosclerotic renovascular disease: a prospective population-based study

OBJECTIVE

Previous reports from select hypertensive patients suggest that atherosclerotic renovascular disease (RVD) is rapidly progressive and associated with a decline in kidney size and kidney function. This prospective, population-based study estimates the incidence of new RVD and progression of established RVD among elderly, free-living participants in the Cardiovascular Health Study (CHS).

METHOD

The CHS is a multicenter, longitudinal cohort study of cardiovascular risk factors, morbidity, and mortality among men and women aged >65 years old. From 1995 through 1996, 834 participants underwent renal duplex sonography (RDS) to define the presence or absence of significant RVD. Between 2002 and 2005, a second RDS study was performed in 119 participants (mean study interval, 8.0 +/- 0.8 years). Significant RVD was defined as hemodynamically significant stenosis (renal artery peak systolic velocity [RA-PSV] exceeding 1.8 m/s) or renal artery occlusion. Prevalent RVD was significant RVD at the first RDS, and incident disease was defined as new significant RVD at the second RDS. Significant change of RVD was defined as a change in RA-PSV of greater than two times the standard deviation of expected change over time, regardless of hemodynamic significance or progression to renal artery occlusion.

RESULTS

The second RDS study cohort included 119 CHS participants with 235 kidneys (35% men; mean age, 82.8 +/- 3.4). On follow-up, no prevalent RVD (n = 13 kidneys; 6.0%) progressed to occlusion. Twenty-nine kidneys without RVD at the first RDS demonstrated significant change in PSV at the second RDS; including nine kidneys with new significant RVD (8 new stenoses; 1 new occlusion). Controlling for within-subject correlation, the overall estimated change in RVD among all 235 kidneys was 14.0% (95% confidence interval [CI], 9.2% to 21.4%), with progression to significant RVD in 4.0% (95% CI, 1.9% to 8.2%). Longitudinal increase in diastolic blood pressure and decrease in renal length were significantly associated with progression to new (ie, incident) significant RVD but not prevalent RVD.

CONCLUSIONS

This is the first prospective, population-based estimate of incident RVD and progression of prevalent RVD among free-living elderly Americans. In contrast to previous reports among select hypertensive patients, CHS participants with a low rate of clinical hypertension demonstrated a significant change of RVD in only 14.0% of kidneys on follow-up of 8 years (annualized rate, 1.3% per year). Progression to significant RVD was observed in only 4.0% (annualized rate, 0.5% per year), and no prevalent RVD progressed to occlusion.

Risk for Incident Renal Dialysis in a Managed Care Population

BACKGROUND

The influence of poorly controlled blood pressure (BP) on progression to end-stage renal disease typically has been studied in qualified populations. Few observational studies examined the influence of change in BP.

METHODS

We conducted a retrospective observational study of a cohort of adults 18 years or older with glomerular filtration rates of 15 to 89 mL/min/1.73 m(2) (0.25 to 1.48 mL/s) in 2001 (N = 16,299) in a managed care organization. The cohort generally was representative of many urban areas in the United States. The principal outcome was incident renal dialysis in 2002 (N = 73). BP was measured in 1999 and 2001. Risk for incident dialysis therapy was estimated in the entire cohort by using Cox proportional hazards regression and in a subset of 4 randomly selected controls (n = 292) matched (for 2001 glomerular filtration rate, age, and sex) with incident dialysis cases by using conditional logistic regression.

RESULTS

Within this cohort, dialysis incidence was 4.5 cases/1,000 adults. For incident dialysis cases, mean time to dialysis therapy in 2002 (from December 31, 2001) was 167 days. Greater levels of systolic or diastolic BP in 1999 were associated significantly with greater risk for incident dialysis treatment in 2002 (controlling for age, sex, coronary artery disease, diabetes, and tobacco use). Decreased systolic or diastolic BP from 1999 to 2001 was associated with significantly reduced risk for incident dialysis treatment in 2002.

CONCLUSION

Improving BP control in adults with early or advanced kidney disease and moderately to severely elevated BP should continue to be a focus of care management programs seeking to decrease the risk for incident dialysis treatment.

Renal duplex parameters, blood pressure, and renal function in elderly people

BACKGROUND

Changes in renal artery and renal parenchyma perfusion are believed to correlate with severity of hypertension and worsened renal function, but population-based studies of these associations are not available. This study examines relationships between parameters derived from renal duplex sonography (RDS), blood pressure (BP), and excretory renal function in a population-based cohort of elderly Americans.

METHODS

Through an ancillary study to the Cardiovascular Health Study, 758 participants (37% men; mean age, 77 years) underwent RDS in which flow velocities and frequency shifts were determined from spectral analysis of Doppler-shifted signals obtained from the renal artery and parenchyma. Associations of these duplex parameters with BP and inverse serum creatinine were examined by using multivariate regression techniques.

RESULTS

Main renal artery peak systolic flow velocity (PSV) showed independent associations with BP, with an SD increase in PSV (0.53 m/s) associated with a 3.3-mm Hg increase in systolic BP (SBP) and a 2.4-mm Hg decrease in diastolic BP (DBP). An SD decrease in end-diastolic frequency shift (EDF; 131 kHz) was associated with a 6.0-mm Hg increase in SBP, a 4.2-mm Hg decrease in DBP, and a significant 3.7% decrease in inverse serum creatinine.

CONCLUSION

Increases in renal artery PSV and decreases in parenchymal EDF are associated with increased SBP and decreased DBP. Moreover, decreased parenchymal EDF showed significant associations with impaired excretory renal function. These results suggest that renal duplex parameters are associated with renal parenchymal changes caused by hypertension and progressive renal dysfunction in elderly people.

Predictors of undiagnosed renal artery stenosis among Japanese patients with risk factors of atherosclerosis

Atherosclerotic renal artery stenosis (ARAS) is a significant cause of end stage renal dysfunction (ESRD) among the elderly. Although early detection of ARAS and induction of adequate treatment could reduce the incidence of ESRD, there have been few reports about parameters predictive of ARAS among Japanese. In this study, we investigated the clinical indicators that predict ARAS among Japanese with risk factors of atherosclerosis (> 40 years of age plus hypertension, dyslipidemia or diabetes mellitus). After eliminating the patients who had already been diagnosed with renal artery stenosis, 202 patients were enrolled. The renal arteries of all 202 patients were evaluated by magnetic resonance arteriography (MRA), and the stenoses with > 50% reduction in diameter at the ostium of the renal artery were defined as ARAS. MRA detected ARAS in 42 patients (31 hemilateral and 11 bilateral). Between the patients with and without ARAS there was no significant difference in gender distribution, detection of abdominal vascular bruits or smoking habit. The prevalences of diabetic, hypertensive and cerebrovascular comorbidity were also not significantly different. The mean blood pressure, body mass index and total serum cholesterol values were similar between the two groups. However, age, pulse pressure, serum uric acid, serum creatinine, amount of urinary protein, and coronary artery comorbidity were significantly higher, while estimated creatinine clearance was significantly lower in the patients with ARAS than in those without ARAS. A high prevalence of hypertensive retinopathy was also noted among patients with ARAS. Multivariate analysis revealed that older age and renal impairment were independent predictors of ARAS in Japanese patients with atherosclerotic risk factors.