Renal function predicts cardiovascular outcomes in southern Italian postmenopausal women

Higher NAFLD fibrosis score is associated with impaired eGFR

BACKGROUND/PURPOSE

Chronic kidney disease (CKD) has become a worldwide health problem, leading to high morbidity and mortality, and non-alcoholic fatty liver disease (NAFLD) is considered a risk factor for CKD. The aim of this study was to explore the relationship between NAFLD fibrosis score (NFS) and the estimated glomerular filtration rate (eGFR), and identify possible risk factors related to the NFS among Taiwanese subjects.

METHODS

Subjects were enrolled from the database of the Department of Preventive Medicine of Kaohsiung Municipal Hsiao-Kang Hospital. The eGFR was calculated according to the Taiwanese Modification of Diet in Renal Disease (TMDRD) equation, and the NFS was employed to evaluate the fibrotic level.

RESULTS

In total, 11,376 subjects were enrolled in this study, with a mean age of 52.0 ± 6.81 years, including 4529 (39.8%) males. A fasting sugar level ≥100 mg/dL (OR = 1.70, 95% CI = 1.52-1.87) and an abnormal waist circumference (OR = 1.81, 95% CI = 1.65-1.99) were significant factors associated with NFS (p < 0.05). Trends of a decreasing TMDRD score and an increasing NFS with increasing age were noted (p < 0.05). The NFS was significantly negatively correlated with the TMDRD score (standard coefficients: -0.067, p < 0.001).

CONCLUSION

A higher NFS is associated with an impaired eGFR in Taiwanese subjects. Controlling risk factors, especially fasting sugar level and waist circumference, may be useful in preventing NFS deterioration, which is negatively correlated with the eGFR.

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.

Uric acid is an independent predictor of cardiovascular events in post-menopausal women

BACKGROUND

Uric acid (UA) is a risk factor for cardiovascular (CV) disease. In post-menopause UA levels are increased and strongly associated with subclinical organ damage. We investigated the prognostic significance of UA levels in predicting CV morbidity and mortality in post-menopausal women.

METHODS

We considered 645 post-menopausal outpatients not taking hormone replacement therapy or any drugs interfering with UA levels. We evaluated major adverse cardiovascular events (MACE) as primary endpoint, with coronary, stroke or total events as secondary endpoint. Survival curves for tertiles of UA were obtained by using the Kaplan-Meier and Mantel methods. Effect of prognostic factors on survival was evaluated by multivariable Cox regression model, considering P<0.05 as statistically significant.

RESULTS

During a mean (SD) follow-up at 72.5 (23.5) months, there were 90 new CV events (2.31%): 62 coronary and 28 cerebrovascular events. The rate of nonfatal CV events (3.15% versus 2.03% and 1.52%, P=0.009) as well as that of MACE (3.23% versus 2.11% and 1.59%, P=0.011) were significantly higher in the third tertile than in the other two groups. Interestingly, cerebrovascular (1.15% versus 0.62% and 0.30%, P=0.027) but not coronary events were significantly different among the three groups. In the Cox regression model, UA was independently and strongly associated with the incident risk of MACE (HR=1.248, P=0.001), cerebrovascular (HR=1.657, P<0.0001) and total events (HR=1.391, P<0.0001).

CONCLUSIONS

In post-menopause, independently of other CV risk factors and menopause duration, UA levels are associated with increased risk of death and MACE, in particular cerebrovascular but not coronary events.

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)

BACKGROUND

Chronic kidney disease (CKD) is associated with accelerated atherosclerosis and adverse cardiovascular outcomes, but mechanisms are unclear. We hypothesized that mild CKD independently predicts adverse outcomes in women with symptoms and signs of ischemia.

METHODS

We categorized 876 women from the Women's Ischemia Syndrome Evaluation cohort according to estimated glomerular filtration rate (eGFR) (eGFR ≥90 mL/min per 1.73 m(2) [normal], 60-89 mL/min per 1.73 m(2) [mild CKD], ≤59 mL/min per 1.73 m(2) [severe CKD]). Time to death from all-cause and cardiovascular causes and major adverse outcomes were assessed by multivariate regression adjusted for baseline covariates.

RESULTS

Obstructive coronary artery disease (CAD) was present only in few patients (39%). Even after adjusting for CAD severity, renal function remained a strong independent predictor of all-cause and cardiac mortality (P < .001). Every 10-unit decrease in eGFR was associated with a 14% increased risk of all-cause mortality (adjusted hazard ratio [AHR] 1.14 [1.08-1.20], P < .0001), 16% increased risk of cardiovascular mortality (AHR 1.16 [1.09-1.23], P < .0001), and 9% increased risk of adverse cardiovascular events (AHR 1.09 [1.03-1.15], P = .002).

CONCLUSIONS

Even mild CKD is a strong independent predictor of all-cause and cardiac mortality in women with symptoms/signs of ischemia, regardless of underlying obstructive CAD severity, underscoring the need to better understand the interactions between ischemic heart disease and CKD.

Vitamin D and 1-hour post-load plasma glucose in hypertensive patients

Background

A plasma glucose value ≥155 mg/dl for 1-hour post-load plasma glucose during an oral glucose tolerance test (OGTT) is able to identify subjects with normal glucose tolerance (NGT) at high-risk for type-2 diabetes and with subclinical organ damage. We designed this study to address if 25-hydroxyvitamin D [25(OH)D] circulating levels are associated with glucose tolerance status, and in particular with 1-hour post-load plasma glucose levels.

Methods

We enrolled 300 consecutive Caucasian hypertensive never-treated outpatients (160 men and 140 women, aged 52.9 ± 9.2 years). Subjects underwent OGTT and measurements of 25(OH)D and standard laboratory tests. Estimated glomerular filtration rate (e-GFR) was calculated by CKD-EPI formula and insulin sensitivity was assessed by Matsuda-index.

Results

Among participants, 230 were NGT, 44 had impaired glucose tolerance (IGT) and 26 had type-2 diabetes. According to 1-h post-load plasma glucose cut-off point of 155 mg/dL, we divided NGT subjects into: NGT < 155 (n = 156) and NGT > 155 mg/dL (n = 74).

NGT ≥ 155 had higher significant fasting and post-load glucose and insulin, parathyroid hormone and hs-CRP levels than NGT < 155. On the contrary, Matsuda-index, e-GFR, and 25(OH)D were significantly lower in NGT ≥ 155 than NGT < 155 subjects. In the multiple regression analysis, 25(OH)D levels resulted the major determinant of 1-h post-load plasma glucose in all population and in the four groups of glucose tolerance status. In the whole population, Matsuda-index, hs-CRP and e-GFR explained another 12.2%, 6.7% and 1.7% of its variation.

Conclusions

Our data demonstrate a significant and inverse relationship between 25(OH)D levels and glucose tolerance status, particularly with 1-h post-load glucose.

Association between noninvasive fibrosis markers and chronic kidney disease among adults with nonalcoholic fatty liver disease

Evidence suggests that nonalcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are associated with an increased risk of chronic kidney disease (CKD). In this study we aimed to evaluate whether the severity of liver fibrosis estimated by NAFLD fibrosis score is associated with higher prevalence of CKD in individuals with NAFLD. To this end NAFLD fibrosis score and estimated glomerular filtration rate (eGFR) were assessed in 570 White individuals with ultrasonography-diagnosed NAFLD. As compared with subjects at low probability of liver fibrosis, individuals at high and intermediate probability showed an unfavorable cardio-metabolic risk profile having significantly higher values of waist circumference, insulin resistance, high sensitivity C-reactive protein, fibrinogen, uric acid and lower insulin-like growth factor-1 levels. Individuals at high and intermediate probability of liver fibrosis have lower eGFR after adjustment for gender, smoking, glucose tolerance status, homeostasis model assessment index of insulin resistance (HOMA-IR index), diagnosis of metabolic syndrome, statin therapy, anti-diabetes and anti-hypertensive treatments (P = 0.001). Individuals at high probability of liver fibrosis had a 5.1-fold increased risk of having CKD (OR 5.13, 95%CI 1.13–23.28; P = 0.03) as compared with individuals at low probability after adjustment for age, gender, and BMI. After adjustment for glucose tolerance status, statin therapy, and anti-hypertensive treatment in addition to gender, individuals at high probability of liver fibrosis had a 3.9-fold increased risk of CKD (OR 3.94, 95%CI 1.11–14.05; P = 0.03) as compared with individuals at low probability. In conclusion, advanced liver fibrosis, determined by noninvasive fibrosis markers, is associated with CKD independently from other known factors.

Role of estrogen in diastolic dysfunction

The prevalence of left ventricular diastolic dysfunction (LVDD) sharply increases in women after menopause and may lead to heart failure. While evidence suggests that estrogens protect the premenopausal heart from hypertension and ventricular remodeling, the specific mechanisms involved remain elusive. Moreover, whether there is a protective role of estrogens against cardiovascular disease, and specifically LVDD, continues to be controversial. Clinical and basic science have implicated activation of the renin-angiotensin-aldosterone system (RAAS), linked to the loss of ovarian estrogens, in the pathogenesis of postmenopausal diastolic dysfunction. As a consequence of increased tissue ANG II and low estrogen, a maladaptive nitric oxide synthase (NOS) system produces ROS that contribute to female sex-specific hypertensive heart disease. Recent insights from rodent models that mimic the cardiac phenotype of an estrogen-insufficient or -deficient woman (e.g., premature ovarian failure or postmenopausal), including the ovariectomized congenic mRen2.Lewis female rat, provide evidence showing that estrogen modulates the tissue RAAS and NOS system and related intracellular signaling pathways, in part via the membrane G protein-coupled receptor 30 (GPR30; also called G protein-coupled estrogen receptor 1). Complementing the cardiovascular research in this field, the echocardiographic correlates of LVDD as well as inherent limitations to its use in preclinical rodent studies will be briefly presented. Understanding the roles of estrogen and GPR30, their interactions with the local RAAS and NOS system, and the relationship of each of these to LVDD is necessary to identify new therapeutic targets and alternative treatments for diastolic heart failure that achieve the cardiovascular benefits of estrogen replacement without its side effects and contraindications.

Impact and interaction of low estimated GFR and B vitamin therapy on prognosis among ischemic stroke patients: the Vitamin Intervention for Stroke Prevention (VISP) trial

BACKGROUND

Low estimated glomerular filtration rate (eGFR) has been linked to higher risk of primary stroke, but little is known about the relation of low eGFR to recurrent vascular risk after stroke. B Vitamin therapy has been used to lower homocysteine levels, but its interaction with kidney function on future major vascular events has not been assessed. The objective of this study was to conduct a secondary analysis based on the Vitamin Intervention for Stroke Prevention (VISP) trial to clarify these issues.

STUDY DESIGN

In the VISP trial, patients with a prior ischemic stroke were randomly assigned to receive the high- or low-dose B vitamin therapy. The trial did not find a difference between randomly assigned groups. The present study is a secondary analysis of the VISP trial.

SETTING & PARTICIPANTS

We analyzed the database of a multicenter trial comprising 3,673 patients with recent ischemic stroke who were followed up for 2 years.

PREDICTOR

We subdivided the cohort based on eGFR into 6 groups (≥105, 90-104, 75-89, 60-74, 45-59, and <45 mL/min/1.73 m²) for the analyses and used eGFR of 60-74 mL/min/1.73 m² as the reference category. Low eGFR was defined as <45 mL/min/1.73 m².

OUTCOMES

The primary end point for this analysis was major vascular events, defined as the composite of nonfatal ischemic stroke, nonfatal myocardial infarction, and vascular death (whichever event came first). The secondary end point was recurrent ischemic stroke. Also, the effects of high-dose B vitamin treatment on future major vascular events according to baseline eGFR categories were analyzed and reported separately.

RESULTS

Mean baseline eGFR was 73.9 ± 21.8 (SD) mL/min/1.73 m². 471 major vascular events during an average of 20 months of follow-up, including 300 recurrent strokes, were recorded. Baseline low eGFR was associated with increased risk of major vascular events (HR, 1.83; 95% CI, 1.32-2.52; P < 0.001) and recurrent stroke (HR, 1.53; 95% CI, 1.01-2.32; P = 0.04) after adjustment for traditional vascular risk factors and homocysteine level. At baseline eGFR <45 mL/min/1.73 m², high-dose B vitamin therapy compared to low dose showed a trend of higher risk of future major vascular events (HR, 1.49; 95% CI, 0.95-2.34; P = 0.08). The overall P value for interaction between B vitamin dose and eGFR was not significant (P = 0.6).

LIMITATIONS

No data for albuminuria.

CONCLUSIONS

Low eGFR is associated with higher risk of future major vascular events and recurrent stroke after a recent ischemic stroke.

Chronic kidney disease in postmenopausal women

Menopause is derived from the Greek words men (month) and pauses (cessation) and means permanent cessation of menstruation after the loss of ovarian activity. Chronic kidney disease (CKD) has recently been associated with cardiovascular events in several studies. CKD patients have a heavy burden of traditional cardiovascular risk factors in addition to a range of nontraditional risk factors such as inflammation and abnormal metabolism of calcium and phosphate. In this review, the association of CKD and cardiovascular disease (CVD), as well as of osteoporosis in postmenopausal women is discussed. CKD mineral and bone disorder, characterized by disturbances of calcium/phosphate/parathyroid hormone, bone abnormalities and vascular and soft tissue calcification, is highly prevalent in CKD and is a strong, independent predictor of bone fracture, CVD and death. Estrogen has been shown to: (a) decrease the expression of angiotensin type 1 receptors in vasculature and kidneys; (b) reduce the expression and activity of angiotensin-converting enzyme, and (c) cause the release of angiotensinogen substrate from the liver. However, the degree of activation or suppression of the renin-angiotensin-aldosterone system by estrogen has not been clearly established. Clinical data on the effects of estrogen therapy on bone mineral densities are extremely limited in the ESRD population. CVD is the most common cause of death in postmenopausal women with CKD and many contributing factors have been explored. Future research for prevention of CVD in postmenopausal women with CKD would focus on the biology of vascular calcification as well as bone loss.

Low glomerular filtration rate and risk of stroke: meta-analysis

OBJECTIVE

To qualitatively and quantitatively investigate the link between a low estimated glomerular filtration rate (eGFR) at baseline and risk of future stroke.

DESIGN

Systematic review and meta-analysis of prospective studies.

DATA SOURCES

PubMed (1966-October 2009) and Embase (1947-October 2009). Selection criteria Inclusion criteria were studies that prospectively collected data within cohort studies or clinical trials, estimated glomerular filtration rate at baseline using the modification of diet in renal disease or Cockcroft-Gault equations, assessed incident stroke, had a follow-up of at least one year, and reported quantitative estimates of multivariate adjusted relative risk and 95% confidence interval for stroke associated with an eGFR of 60-90 ml/min/1.73 m(2) or <60 ml/min/1.73 m(2). Data abstraction Two investigators independently abstracted data from eligible studies. Estimates were combined using a random effects model. Heterogeneity was assessed by P value of χ(2) statistics and I(2). Publication bias was assessed by visual examination of funnel plots.

RESULTS

21 articles derived from 33 prospective studies: 14 articles assessed eGFR <60 ml/min/1.73 m(2) and seven assessed eGRF at both <60 ml/min/1.73 m(2) and 60-90 ml/min/1.73 m(2) for a total of 284 672 participants (follow-up 3.2-15 years) with 7863 stroke events. Incident stroke risk increased among participants with an eGFR <60 ml/min/1.73 m(2) (relative risk 1.43, 95% confidence interval 1.31 to 1.57; P<0.001) but not among those with an eGFR of 60-90 ml/min/1.73 m(2) (1.07, 0.98 to 1.17; P=0.15). Significant heterogeneity existed between estimates among patients with an eGFR <60 ml/min/1.73 m(2) (P<0.001). In subgroup analyses among participants with an eGFR <60 ml/min/1.73 m(2), heterogeneity was significant in Asians compared with non-Asians (1.96, 1.73 to 2.23 v 1.25, 1.16 to 1.35; P<0.001), and those with an eGFR of 40-60 ml/min/1.73 m(2) v <40 ml/min/1.73 m(2) (1.28, 1.04 to 1.56 v 1.77, 1.32 to 2.38; P<0.01).

CONCLUSIONS

A baseline eGFR <60 ml/min/1.73 m(2) was independently related to incident stroke across a variety of participants and study designs. Prompt and appropriate implementation of established strategies for reduction of vascular risk in people with know renal insufficiency may prevent future strokes.

Chronic renal insufficiency, cardiovascular disease and mortality in women: a causal relationship or coincidence?

Evaluation of: Kurth T, de Jong PE, Cook NR, Buring J: Kidney function and risk of cardiovascular disease and mortality in women: a prospective cohort study. BMJ 338, B2769 (2009). The incidence of cardiovascular disease events and cardiovascular death in a cohort of 27,939 apparently healthy female health professionals over 45 years of age (Women's Health Study) who were stratified by estimated glomerular filtration rate (GFR) and followed for 12 years was assessed. Women with a GFR less than 60 ml/min/1.73 m(2) demonstrated an increased risk of death from cardiovascular disease (HR: 1.68; 95% CI: 1.02-2.79) compared with women with a GFR higher than 90 ml/min/1.73 m(2). There was no difference in risk when groups with decreased GFR of different ranges were compared with the group of women with normal GFR for first cardiovascular disease, all-cause mortality, myocardial infarction, stroke, coronary revascularization and noncardiovascular death.