Mild renal dysfunction and long-term adverse outcomes in women with chest pain: results from the National Heart, Lung, and Blood Institute-sponsored Women's Ischemia Syndrome Evaluation (WISE)

Polygenic association of glomerular filtration rate decline in world trade center responders

BACKGROUND

The factors associated with estimated glomerular filtrate rate (eGFR) decline in low risk adults remain relatively unknown. We hypothesized that a polygenic risk score (PRS) will be associated with eGFR decline.

METHODS

We analyzed genetic data from 1,601 adult participants with European ancestry in the World Trade Center Health Program (baseline age 49.68 ± 8.79 years, 93% male, 23% hypertensive, 7% diabetic and 1% with cardiovascular disease) with ≥ three serial measures of serum creatinine. PRSs were calculated from an aggregation of single nucleotide polymorphisms (SNPs) from a recent, large-scale genome-wide association study (GWAS) of rapid eGFR decline. Generalized linear models were used to evaluate the association of PRS with renal outcomes: baseline eGFR and CKD stage, rate of change in eGFR, stable versus declining eGFR over a 3-5-year observation period. eGFR decline was defined in separate analyses as "clinical" (> -1.0 ml/min/1.73 m2/year) or "empirical" (lower most quartile of eGFR slopes).

RESULTS

The mean baseline eGFR was ~ 86 ml/min/1.73 m2. Subjects with decline in eGFR were more likely to be diabetic. PRS was significantly associated with lower baseline eGFR (B = -0.96, p = 0.002), higher CKD stage (OR = 1.17, p = 0.010), decline in eGFR (OR = 1.14, p = 0.036) relative to stable eGFR, and the lower quartile of eGFR slopes (OR = 1.21, p = 0.008), after adjusting for established risk factors for CKD.

CONCLUSION

Common genetic variants are associated with eGFR decline in middle-aged adults with relatively low comorbidity burdens.

The effect of systemic factors on retinal blood flow in patients with carotid stenosis: an optical coherence tomography angiography study

Carotid artery stenosis (CAS) is among the leading causes of mortality and permanent disabilities in the Western world. CAS is a consequence of systemic atherosclerotic disease affecting the majority of the aging population. Optical coherence tomography angiography (OCTA) is a novel imaging technique for visualizing retinal blood flow. It is a noninvasive, fast method for qualitative and quantitative assessment of the microcirculation. Cerebral and retinal circulation share similar anatomy, physiology, and embryology; thus, retinal microvasculature provides a unique opportunity to study the pathogenesis of cerebral small vessel disease in vivo. In this study, we aimed to analyze the effect of systemic risk factors on retinal blood flow in the eyes of patients with significant carotid artery stenosis using OCT angiography. A total of 112 eyes of 56 patients with significant carotid stenosis were included in the study. We found that several systemic factors, such as decreased estimated glomerular filtration rate (eGFR), hypertension, and carotid occlusion have a significant negative effect on retinal blood flow, while statin use and carotid surgery substantially improve ocular microcirculation. Neither diabetes, clopidogrel or acetylsalicylic acid use, BMI, serum lipid level, nor thrombocyte count showed a significant effect on ocular blood flow. Our results demonstrate that a systematic connection does exist between certain systemic risk factors and retinal blood flow in this patient population. OCTA could help in the assessment of cerebral circulation of patients with CAS due to its ability to detect subtle changes in retinal microcirculation that is considered to represent changes in intracranial blood flow.

The Association of Posttraumatic Stress Disorder With Longitudinal Change in Glomerular Filtration Rate in World Trade Center Responders

OBJECTIVE

High levels of psychological distress increase the risk of a wide range of medical diseases. In this study, we investigated the association between posttraumatic stress disorder (PTSD) and kidney disease.

METHODS

World Trade Center (WTC) responders were included if they had two or more measures of estimated glomerular filtration rate (eGFR). The PTSD Checklist (PCL) was used to define no PTSD (PCL < 40), "mild" PTSD (40 ≤ PCL <50), and "severe" PTSD (PCL ≥50). Subtypes of PTSD by symptom clusters were analyzed. Multinomial logistic regression was used to estimate the association of PTSD with two GFR change outcomes (decline or increase) compared with the stable GFR outcome.

RESULTS

In 2266 participants, the mean age was 53.1 years, 8.2% were female, and 89.1% were White. Individuals with PTSD (n = 373; 16.5%) did not differ in mean baseline GFR from individuals without PTSD (89.73 versus 90.56 mL min-1 1.73 m-2; p = .29). During a 2.01-year mean follow-up, a mean GFR decline of -1.51 mL min-1 1.73 m-2 per year was noted. In multivariable-adjusted models, PTSD was associated with GFR decline (adjusted relative risk [aRR] = 1.74 [1.32-2.30], p < .001) compared with stable GFR, with "hyperarousal" symptoms showing the strongest association (aRR =2.11 [1.40-3.19]; p < .001). Dose-response effects were evident when comparing mild with severe PTSD and comparing PTSD with versus without depression. PTSD was also associated with GFR rise (aRR = 1.47 [1.10-1.97], p < .009). The association between PTSD and GFR change was stronger in participants older than 50 years.

CONCLUSIONS

PTSD may be a novel risk factor for exaggerated longitudinal GFR change in young, healthy adults. These findings need to be validated in other cohorts.

Association of Mildly Reduced Kidney Function With Cardiovascular Disease: The Framingham Heart Study

Background Data are limited on the association of mildly reduced estimated glomerular filtration rate (eGFR 60-89 mL/min per 1.73 m²) with cardiovascular disease (CVD) in the community. Methods and Results We evaluated 3066 Framingham Offspring Study participants (55% women, mean age 58 years), without clinical CVD. Using multivariable regression, we related categories of mildly reduced eGFR (80-89, 70-79, or 60-69 versus ≥90 mL/min per 1.73 m² [referent]) to prevalent coronary artery calcium, carotid intima media thickness, and left ventricular hypertrophy, and to circulating concentrations of cardiac stress biomarkers. We related eGFR categories to CVD incidence and to progression to ≥Stage 3 chronic kidney disease (eGFR <60 mL/min per 1.73 m²) using Cox regression. Individuals with eGFR 60-69 mL/min per 1.73 m² (n=320) had higher coronary artery calcium score (odds ratio 1.69; 95% CI 1.02-2.80) compared with the referent group. Individuals with eGFR 60-69 and 70-79 mL/min per 1.73 m² had higher blood growth differentiating factor-15 concentrations (β=0.131 and 0.058 per unit-increase in log-biomarker, respectively). Participants with eGFR 60-69 and 80-89 mL/min per 1.73 m² had higher blood B-type natriuretic peptide concentrations (β=0.119 and 0.116, respectively). On follow-up (median 16 years; 691 incident CVD and 252 chronic kidney disease events), individuals with eGFR 60-69 and 70-79 mL/min per 1.73 m² experienced higher CVD incidence (hazard ratio [HR], 1.40; 95% CI, 1.02-1.93 and 1.45, 95% CI, 1.05-2.00, respectively, versus referent). Participants with eGFR 60-69 mL/min per 1.73 m² experienced higher chronic kidney disease incidence (HR, 2.94; 95% CI, 1.80-4.78 versus referent). Conclusions Individuals with mildly reduced eGFR 60-69 mL/min per 1.73 m² have a higher burden of subclinical atherosclerosis cross-sectionally, and a greater risk of CVD and chronic kidney disease progression prospectively. Additional studies are warranted to confirm our findings.

Microvascular dysfunction and kidney disease: Challenges and opportunities?

Kidneys are highly vascular organs that despite their relatively small size receive 20% of the cardiac output. The highly intricate, delicately organized structure of renal microcirculation is essential to enable renal function and glomerular filtration rate through the local modulation of renal blood flow and intraglomerular pressure. Not surprisingly, the dysregulation of blood flow within the microvessels (abnormal vasoreactivity), fibrosis driven by disordered vascular-renal cross talk, or the loss of renal microvasculature (rarefaction) is associated with kidney disease. In addition, kidney disease can cause microcirculatory dysfunction in distant organs such as the heart and brain, mediated by mechanisms that remain to be elucidated. The objective of this review is to highlight the role of renal microvasculature in kidney disease. The overview will outline the impetus to study renal microvasculature, the bidirectional relationship between kidney disease and microvascular dysfunction, the key pathways driving microvascular diseases such as vasoreactivity, the cell dynamics coordinating fibrosis, and vessel rarefaction. Finally, we will also briefly highlight new therapies targeting the renal microvasculature to improve renal function.

Even "WISE-R?"-an Update on the NHLBI-Sponsored Women's Ischemia Syndrome Evaluation

PURPOSE OF REVIEW

For over 20 years, the Women's Ischemia Syndrome Evaluation (WISE), a program sponsored by the National Heart, Lung, and Blood Institute, has explored diverse and important aspects of ischemic heart disease in women.

RECENT FINDINGS

Women with symptoms and signs of ischemia but no significant epicardial obstructive coronary artery disease (INOCA) were documented to be at elevated risk for recurrent angina hospitalization, major adverse cardiac events, death, and health resource consumption rivaling those with obstructive coronary disease. WISE investigators have advanced our understanding of cardiovascular outcomes, systemic manifestations, psychological variables, socioeconomic factors, genetic contributions, hormonal status, advanced imaging, coronary functional findings, biomarkers, patient-reported outcomes, and treatments pertaining to women with this disease entity. This review delves into the WISE findings subsequent to a prior review1, postulates directions for future research, and asks are we "Even 'WISE-R?'".

Cardiovascular Disease Outcomes Related to Early Stage Renal Impairment After Liver Transplantation

BACKGROUND

In the general population, even mild renal disease is associated with increased cardiovascular (CV) complications. Whether this is true in liver transplant recipients (LTR) is unknown.

METHODS

This was a retrospective cohort study of 671 LTR (2002-2012) from a large urban tertiary care center and 37 322 LTR using Vizient hospitalization data linked to the United Network for Organ Sharing. The 4-variable Modification of Diet in Renal Disease equation estimated glomerular filtration rate (eGFR). Outcomes were 1-year CV complications (death/hospitalization from myocardial infarction, heart failure, atrial fibrillation, cardiac arrest, pulmonary embolism, or stroke) and mortality. Latent mixture modeling identified trajectories in eGFR in the first liver transplantation (LT) year in the 671 patients.

RESULTS

Mean (SD) eGFR was 72.1 (45.7) mL/min per 1.73 m. Six distinct eGFR trajectories were identified in the local cohort (n = 671): qualitatively normal-slow decrease (4% of cohort), normal-rapid decrease (4%), mild-stable (18%), mild-slow decrease (35%), moderate-stable (30%), and severe-stable (9%). In multivariable analyses adjusted for confounders and baseline eGFR, the greatest odds of 1-year CV complications were in the normal-rapid decrease group (odds ratio, 10.6; 95% confidence interval, 3.0-36.9). Among the national cohort, each 5-unit lower eGFR at LT was associated with a 2% and 5% higher hazard of all-cause and CV-mortality, respectively (P < 0.0001), independent of multiple confounders.

CONCLUSIONS

Even mild renal disease at the time of LT is a risk factor for posttransplant all-cause and CV mortality. More rapid declines in eGFR soon after LT correlate with risk of adverse CV outcomes, highlighting the need to study whether early renal preservation interventions also reduce CV complications.

Long-term prognosis of chronic kidney disease in non-ST elevation acute coronary syndrome treated with invasive strategy

BACKGROUND AND AIM

Patients with chronic kidney disease (CKD) have an increased risk of adverse cardiovascular outcomes after non-ST elevation acute coronary syndrome (NSTEACS). However, the information available on this specific population, is scarce. We evaluate the impact of CKD on long-term prognosis in patients with NSTEACS managed with invasive strategy.

METHODS

We conduct a prospective registry of patients with NSTEACS and coronary angiography. CKD was defined as a glomerular filtration rate < 60ml/min/1,73m². The composite primary end-point was cardiac death and non fatal cardiovascular readmission. We estimated the cumulative probability and hazard rate (HR) of combined primary end-point at 3-years according to the presence or absence of CKD.

RESULTS

We included 248 p with mean age of 66.9 years, 25% women. CKD was present at baseline in 67 patients (27%). Patients with CKD were older (74.9 vs. 63.9 years; P<.0001) with more prevalence of hypertension (89.6 vs. 66.3%; P<.0001), diabetes (53.7 vs. 35.9%; P=.011), history of heart failure (13.4 vs. 3.9%; P=.006) and anemia (47.8 vs. 16%; P<.0001). No differences in the extent of coronary artery disease. CKD was associated with higher cumulative probability (49.3 vs. 28.2%; log-rank P=.001) and HR of the primary combined end-point (HR: 1.94; CI95%: 1.12-3.27; P=.012). CKD was an independent predictor of adverse cardiovascular outcomes at 3-years (HR: 1.66; CI95%: 1.05-2.61; P=.03).

CONCLUSIONS

In NSTEACS patients treated with invasive strategie CKD is associated independently with an increased risk of adverse cardiovascular outcomes at 3years.

Fast GFR decline and progression to CKD among primary care patients with preserved GFR

BACKGROUND

Fast glomerular filtration rate (GFR) decline is associated with adverse outcomes, but the associated risk factors among patients without chronic kidney disease (CKD) are not well defined.

METHODS

From a primary care registry of 37,796, we identified 2219 (6%) adults with at least three estimated (e)GFR values and a baseline eGFR between 60 and 119 ml/min/1.73 m² during an observation period of 8 years. We defined fast GFR decline as > 5 ml/min/1.73 m² per year. The outcome measure was incident CKD (eGFR < 60 ml/min/1.73 m²). Clinical and demographic characteristics were compared using Chi-square and independent-samples t tests.

RESULTS

Older age, African-American race, unmarried status, hypertension and type 2 diabetes were more common in both fast decliners and those who developed incident CKD (p < 0.0001 to < 0.05). Lower neighborhood socioeconomic status, current smoking and baseline eGFR 90-119 ml/min/1.73 m² were associated with fast decline (p < 0.01), while baseline eGFR 60-74 ml/min/1.73 m² with incident CKD (p < 0.05). In multivariate regression models, among fast decliners with mildly reduced baseline eGFR (60-89 ml/min/1.73 m²), older age was significantly associated with incident CKD [odds ratio (OR) 1.04; 95% CI 1.01-1.08], and among those with normal baseline eGFR (≥ 90-119 ml/min/1.73 m²), type 2 diabetes was significantly associated with incident CKD (OR 3.83; 95% CI 1.35-10.89).

CONCLUSIONS

Among primary care patients without CKD, GFR is checked infrequently. We have identified patients at high risk of progressive CKD, in whom we suggest a closer monitoring of renal function.

Association of Mild-to-Moderate Reduction in Glomerular Filtration Rate with Subclinical Atherosclerosis in Postmenopausal Women

BACKGROUND

Due to loss of hormonal protective effects, postmenopausal women have an increased cardiovascular (CV) risk. Chronic kidney disease (CKD) is a well-established risk factor for CV disease, but little is known whether mild-to-moderate kidney dysfunction is associated with atherosclerosis burden in the postmenopausal asymptomatic women.

MATERIALS AND METHODS

Subclinical atherosclerosis was evaluated in 125 postmenopausal women with no clinical form of atherosclerosis, by carotid and femoral ultrasonography, ankle-brachial index (ABI), and flow-mediated dilation (FMD). Carotid and femoral atherosclerosis were defined as increased intima-media thickness (IMT) and/or the presence of plaques. Endothelial function was assessed by endothelial dependent (flow-mediated dilation at 1 minute [FMD₁]) and independent (flow-mediated dilation after nitroglycerin [FMD_NTG]) vasodilation. Classical CV risk factors (age, smoking, obesity, diabetes, blood pressure, and lipids) were evaluated. Kidney function was evaluated in terms of estimated glomerular filtration rate (eGFR) calculated by the CKD-EPI formula. Univariate linear regression and multivariate logistic regressions were used to evaluate the independent associations between kidney function and markers of subclinical atherosclerosis.

RESULTS

In the unadjusted linear analysis, eGFR showed a significant negative association with markers of subclinical atherosclerosis: carotid IMT (R² = 0.305; p < 0.001), femoral IMT (R² = 0.19, p < 0.001), carotid plaques (R² = 0.22; p < 0.001), femoral plaques (R² = 0.09; p = 0.0005), ABI (R² = 0.05; p = 0.01), FMD₁ (R² = 0.45; p < 0.001), and FMD_NTG (R² = 0.205, p < 0.001). After adjustment for classical CV risk factors the association remained significant.

CONCLUSIONS

Mild-to-moderate reduced eGFR is related to subclinical atherosclerosis, independent of traditional CV risk factors. It is important to detect renal function decline, even if it is mild, to improve risk stratification of subclinical atherosclerosis in postmenopausal women.

Renal acoustic radiation force impulse elastography in the evaluation of coronary artery disease

Background Renal insufficiency may occur in patients with coronary artery disease (CAD). Acoustic radiation force impulse (ARFI) is a method for quantifying tissue elasticity, which could be used as an additional diagnostic test for renal insufficiency and provide an additional contribution to the determination of CAD. Purpose To evaluate ARFI elastography with shear wave velocity (SWV) measurements in the diagnosis of mild-to-moderate chronic kidney disease (CKD) in CAD patients, and to analyze the relationship between the severity of CAD assessed by the Gensini scoring system and kidney stiffness. Material and Methods The study included 76 CAD patients and 79 healthy volunteers. SWV was measured for each kidney in the both groups. The CAD group was divided into two subgroups based on Gensini score: mild CAD and severe CAD. SWV values of the CAD patients were compared to those of the healthy volunteers; values of subgroups were also compared with each other. Results The patient group had significantly lower renal mean SWV values than those of the healthy group (1.87 ± 0.58 vs. 2.34 ± 0.38, P < 0.01). The SWV value decreased as the eGFR level decreased. Mean SWV values for kidneys of the patients with severe CAD were lower than those of the mild CAD patients (1.64 ± 0.39 vs. 2.42 ± 0.60, P < 0.01). Conclusion renal mean SWV values of CAD patients decreased in proportion to the reduction in eGFR, and the SWV values decreased as the severity of CAD increased. ARFI elastography is a novel technique for diagnosing CKD and defining illness severity in CAD patients.

Fractional Flow Reserve Evaluation and Chronic Kidney Disease: Analysis From a Multicenter Italian Registry (the FREAK Study)

OBJECTIVES

To establish if the presence of chronic kidney disease (CKD) influences fractional flow reserve (FFR) value in patients with intermediate coronary stenosis.

BACKGROUND

FFR-guided coronary revascularization reduces cardiac adverse events in patients with coronary artery disease. CKD impairs microcirculation and increases cardiovascular risk. Whether CKD presence may limit FFR accuracy is unknown.

METHODS

We used data from a multicenter prospective registry enrolling 1.004 patients undergoing FFR evaluation for intermediate stenosis. We assessed the relationship between clinical and angiographic variables and FFR measurement. CKD was defined as CrCl value ≤45 ml/min. FFR value was considered potentially flow-limiting, and therefore positive, if ≤0.80. The index of microcirculatory resistance (IMR) was calculated in 20 patients stratified according CrCl value (single-center substudy).

RESULTS

FFR measurement was positive in 395 (39%) patients. Overall, 131 (13%) patients had CKD. Patients with CrCl ≤45 ml/min showed significantly higher FFR values as compared to the others (0.84 ± 0.07 vs. 0.81 ± 0.08, p < 0.001). Positive FFR occurrence was lower in patients with CrCl ≤45 ml/min (27% vs. 41%, p < 0.01). After multivariable analysis, diabetes (HR 1.07, 95%CI 1.008-1.13, p = 0.03), left anterior descending (HR 1.35, 95%CI 1.27-1.43, p < 0.001) and CrCl ≤45 ml/min (HR 0.92, 95%CI 0.87-0.97, p = 0.005) emerged as independent predictors of FFR measurement. Accordingly, IMR values were higher in patients with CrCl ≤45 ml/min (32 U [28245] vs. 16 U [11220], p < 0.01).

CONCLUSIONS

FFR and IMR measurements differ between CKD patients and those with normal renal function. Flow-limiting FFR is less frequent in patients with CrCl ≤45 ml/min. © 2015 Wiley Periodicals, Inc.

Relationship between Serum Uric Acid Levels and Chronic Kidney Disease in a Japanese Cohort with Normal or Mildly Reduced Kidney Function

Background

Some observational studies have shown the relationships between hyperuricemia and chronic kidney disease (CKD); however, the threshold of serum uric acid (SUA) for deterioration of kidney function and the association between SUA and kidney injury by baseline kidney function remains unclear. This study aimed to clarify the relationships between SUA and reduced kidney function.

Methods

We analyzed a historical cohort of male Japanese individuals who underwent medical checkup between 1998 and 2007. Participants with baseline data and who were followed up for at least one year were included and stratified according to baseline kidney function. Kidney function was classified as normal [estimated glomerular filtration rate (eGFR) ≥ 90 ml/min/1.73 m²] or mildly reduced (eGFR 60–89 ml/min/1.73 m²). The outcome measured was kidney impairment defined as a decrease in eGFR to < 60 ml/min/1.73 m². Associations between SUA and risk for outcome and eGFR slopes were assessed.

Results

A total of 41632 subjects with mean age 45.4 years were included. During a mean follow-up of four years, 3186 (7.6%) subjects developed kidney dysfunction. Subjects with SUA ≥ 6.0 mg/dL had a significantly increased risk for kidney impairment compared with subjects with SUA of 4–4.9 mg/dL. SUA threshold levels were different according to baseline kidney function; SUA ≥ 7.0 and ≥ 6.0 mg/dL for normal and mildly reduced kidney function, respectively. Approximately the same trends were observed for eGFR slopes.

Conclusion

In the general population, hyperuricemia appears to be a risk factor for kidney impairment in males. For participants with mild kidney dysfunction, even a slight elevation of SUA can be a risk factor.