Blood pressure control, proteinuria, and the progression of renal disease. The Modification of Diet in Renal Disease Study

Canadian Society of Nephrology commentary on the 2012 KDIGO clinical practice guideline for the management of blood pressure in CKD

The KDIGO (Kidney Disease: Improving Global Outcomes) 2012 clinical practice guideline for the management of blood pressure (BP) in chronic kidney disease (CKD) provides the structural and evidence base for the Canadian Society of Nephrology (CSN) commentary on this guideline's relevancy and application to the Canadian health care system. While in general agreement, we provide commentary on 13 of the 21 KDIGO guideline statements. Specifically, we agreed that nonpharmacological interventions should play a significant role in the management of hypertension in patients with CKD. We also agreed that the approach to the management of hypertension in elderly patients with CKD should be individualized and take into account comorbid conditions to avoid adverse outcomes from excessive BP lowering. In contrast to KDIGO, the CSN Work Group believes there is insufficient evidence to target a lower BP for nondiabetic CKD patients based on the presence and severity of albuminuria. The CSN Work Group concurs with the Canadian Hypertension Education Program (CHEP) recommendation of a target BP for all non-dialysis-dependent CKD patients without diabetes of ≤140 mm Hg systolic and ≤90 mm Hg diastolic. Similarly, it is our position that in diabetic patients with CKD and normal urinary albumin excretion, raising the threshold for treatment from <130 mm Hg systolic BP to <140 mm Hg systolic BP could increase stroke risk and the risk of worsening kidney disease. The CSN Work Group concurs with the CHEP and the Canadian Diabetic Association recommendation for diabetic patients with CKD with or without albuminuria to continue to be treated to a BP target similar to that of the overall diabetes population, aiming for BP levels < 130/80 mm Hg. Consistent with this, the CSN Work Group endorses a BP target of <130/80 mm Hg for diabetic patients with a kidney transplant. Finally, in the absence of evidence for a lower BP target, the CSN Work Group concurs with the CHEP recommendation to target BP<140/90 mm Hg for nondiabetic patients with a kidney transplant.

Treatment Strategies to Prevent Renal Damage in Hypertensive Children

Hypertension secondary to chronic kidney disease prevails in earlier childhood and obesity-related primary hypertension in adolescence. Both are associated with a high risk of renal and cardiovascular morbidity. In children with chronic kidney disease, uncontrolled hypertension may accelerate progression to end-stage renal disease before adulthood is reached and increase a child’s risk of cardiac death a thousand-fold. Obesity-related hypertension is a slow and silent killer, and though early markers of renal damage are recognized during childhood, end-stage renal disease is a risk in later life. Renal damage will be a formidable multiplier of cardiovascular risk for adults in whom obesity and hypertension tracks from childhood. Management options to prevent renal damage will vary for these different target groups. This review provides a summary of the available renoprotective strategies in order to aid physicians involved in the care of this challenging group of children.

Optimizing blood pressure control in patients with nondiabetic glomerular disease

Hypertension is a common problem among patients with glomerular disease and CKD. Optimal blood pressure targets for these patients have been the source of much debate. Careful review of the available data supports a blood pressure target of less than 140/90 mmHg. Consideration for a lower goal of less than 130/80 mmHg should be given for patients with heavy proteinuria. Renin-angiotensin system inhibitors should be used as the cornerstone of therapy for all patients with glomerular disease and CKD.

Role of chemokines in proteinuric kidney disorders

Experimental and human studies have shown that proteinuria contributes to the progression of renal disease. Overexposure to filtered proteins promotes the expression and release of chemokines by tubular epithelial cells, thus leading to inflammatory cell recruitment and renal impairment. This review focuses on recent progress in cellular and molecular understanding of the role of chemokines in the pathogenesis of proteinuria-induced renal injury, as well as their clinical implications and therapeutic potential.

Lipotoxic disruption of NHE1 interaction with PI(4,5)P2 expedites proximal tubule apoptosis

Chronic kidney disease progression can be predicted based on the degree of tubular atrophy, which is the result of proximal tubule apoptosis. The Na+/H+ exchanger NHE1 regulates proximal tubule cell survival through interaction with phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2], but pathophysiologic triggers for NHE1 inactivation are unknown. Because glomerular injury permits proximal tubule luminal exposure and reabsorption of fatty acid/albumin complexes, we hypothesized that accumulation of amphipathic, long-chain acyl-CoA (LC-CoA) metabolites stimulates lipoapoptosis by competing with the structurally similar PI(4,5)P2 for NHE1 binding. Kidneys from mouse models of progressive, albuminuric kidney disease exhibited increased fatty acids, LC-CoAs, and caspase-2-dependent proximal tubule lipoapoptosis. LC-CoAs and the cytosolic domain of NHE1 directly interacted, with an affinity comparable to that of the PI(4,5)P2-NHE1 interaction, and competing LC-CoAs disrupted binding of the NHE1 cytosolic tail to PI(4,5)P2. Inhibition of LC-CoA catabolism reduced NHE1 activity and enhanced apoptosis, whereas inhibition of proximal tubule LC-CoA generation preserved NHE1 activity and protected against apoptosis. Our data indicate that albuminuria/lipiduria enhances lipotoxin delivery to the proximal tubule and accumulation of LC-CoAs contributes to tubular atrophy by severing the NHE1-PI(4,5)P2 interaction, thereby lowering the apoptotic threshold. Furthermore, these data suggest that NHE1 functions as a metabolic sensor for lipotoxicity.

Proteinuria, (99m) Tc-DTPA Scintigraphy, Creatinine-, Cystatin- and Combined-Based Equations in the Assessment of Chronic Kidney Disease

Background. Precise estimation of the glomerular filtration rate (GFR) and the identification of markers of progression are important. We compared creatinine, cystatin, and combined CKD-EPI equations with ^99mTc-DTPA scintigraphy to measure GFR and proteinuria as markers of progression. Methods. Cross-sectional, observational study including 300 subjects. CKD was classified by ^99mTc-DTPA scintigraphy. Determinations. Creatinine, 24-hour creatinine clearance, cystatin, Hoek formula, and creatinine, cystatin, and combined CKD-EPI equations. Results. In the global assessment, creatinine CKD-EPI and combined CKD-EPI equations yielded the highest correlations with ^99mTc-DTPA: ρ = 0.839, P < 0.0001 and ρ = 0.831, P < 0.0001. Intergroup analysis versus ^99mTc-DTPA: control G, creatinine clearance ρ = 0.414, P = 0.013; G3, combined CKD-EPI ρ = 0.5317, P < 0.0001; G4, Hoek ρ = 0.618, P < 0.0001, combined CKD-EPI ρ = 0.4638, P < 0.0001; and G5, creatinine clearance ρ = 0.5414, P < 0.0001, combined CKD-EPI ρ = 0.5288, P < 0.0001. In the global assessment, proteinuria displayed the highest significant correlations with cystatin (ρ = 0.5433, P < 0.0001) and cystatin-based equations (Hoek: ρ = −0.5309, P < 0.0001). When GFR < 60 mL/min: in stage 3, proteinuria-cystatin (ρ = 0.4341, P < 0.0001); proteinuria-Hoek (ρ = −0.4105, P < 0.0001); in stage 4, proteinuria-cystatin (ρ = 0.4877, P < 0.0001); proteinuria-Hoek (ρ = −0.4877, P = 0.0026). Conclusions. At every stage of GFR < 60 mL/min, cystatin-based equations displayed better correlations with ^99mTc-DTPA. Proteinuria and cystatin-based equations showed strong associations and high degrees of correlation.

Hypertension in Chronic Kidney Disease - Role of Arterial Calcification and Impact on Treatment

Hypertension contributes to the progression of kidney diseases as well as to the occurrence of cardiovascular events such as myocardial infarction, heart failure and stroke. The prevalence of hypertension is elevated in patients with kidney disease, and increases progressively as glomerular filtration rate falls. A better understanding of the mechanisms leading to hypertension in renal diseases has been gained in recent years; in this article we will review the pathogenesis of hypertension in chronic kidney disease (CKD) with a special focus on vascular calcification because calcification is associated with an increased incidence of cardiovascular morbidity in CKD patients. Although calcification of large arteries and blood pressure increase with age, few studies have specifically investigated a possible connection between these two factors as determinants of the severity of hypertension in CKD. Finally, we will review the trends in hypertension treatment in CKD patients. Expanded understanding of the role of CKD as both a cause and a target of hypertension highlights key points of pathophysiology of hypertension and may contribute to the identification of new strategies for its prevention and treatment.

Vascular endothelial growth factor inhibitor-induced hypertension: from pathophysiology to prevention and treatment based on long-acting nitric oxide donors

Hypertension is the most common adverse effect of the inhibitors of vascular endothelial growth factor (VEGF) pathway-based therapy (VEGF pathway inhibitors therapy, VPI therapy) in cancer patients. VPI includes monoclonal antibodies against VEGF, tyrosine kinase inhibitors, VEGF Traps, and so-called aptamers that may become clinically relevant in the future. All of these substances inhibit the VEGF pathway, which in turn causes a decrease in nitric oxide (NO) and an increase in blood pressure, with the consequent development of hypertension and its final events (e.g., myocardial infarction or stroke). To our knowledge, there is no current study on how to provide an optimal therapy for patients on VPI therapy with hypertension. This review summarizes the roles of VEGF and NO in vessel biology, provides an overview of VPI agents, and suggests a potential treatment procedure for patients with VPI-induced hypertension.

Effects of unilateral nephrectomy on renal function in male Spontaneously Diabetic Torii fatty rats: a novel obese type 2 diabetic model

The Spontaneously Diabetic Torii (SDT) fatty rat is a new model for obese type 2 diabetes. The aim of the present study was to investigate the effect of 1/2 nephrectomy (Nx) on renal function and morphology and on blood pressure in SDT fatty rats. Male SDT fatty rats underwent 1/2 Nx or a sham operation (Sham). Subsequently, animals were studied with respect to renal function and histological alterations. Induction of 1/2 Nx in SDT fatty rats led to functional and morphological damage to the remnant kidney and to hypertension, which are considered main characteristics of chronic kidney disease, at a younger age compared with the sham group. In conclusion, the SDT fatty rat is useful in investigations to elucidate the pathogenesis of human diabetic nephropathy and in new drug discovery.

Proteinuria and its relation to cardiovascular disease

Chronic kidney disease (CKD) and its associated morbidity pose a worldwide health problem. As well as risk of endstage renal disease requiring renal replacement therapy, cardiovascular disease is the leading cause of premature death among the CKD population. Proteinuria is a marker of renal injury that can often be detected earlier than any tangible decline in glomerular filtration rate. As well as being a risk marker for decline in renal function, proteinuria is now widely accepted as an independent risk factor for cardiovascular morbidity and mortality. This review will address the prognostic implications of proteinuria in the general population as well as other specific disease states including diabetes, hypertension and heart failure. A variety of pathophysiological mechanisms that may underlie the relationship between renal and cardiovascular disease have been proposed, including insulin resistance, inflammation, and endothelial dysfunction. As proteinuria has evolved into a therapeutic target for cardiovascular risk reduction in the clinical setting we will also review therapeutic strategies that should be considered for patients with persistent proteinuria.

The role of autophagy in the pathogenesis of diabetic nephropathy

Diabetic nephropathy is a leading cause of end-stage renal disease worldwide. The multipronged drug approach targeting blood pressure and serum levels of glucose, insulin, and lipids fails to fully prevent the onset and progression of diabetic nephropathy. Therefore, a new therapeutic target to combat diabetic nephropathy is required. Autophagy is a catabolic process that degrades damaged proteins and organelles in mammalian cells and plays a critical role in maintaining cellular homeostasis. The accumulation of proteins and organelles damaged by hyperglycemia and other diabetes-related metabolic changes is highly associated with the development of diabetic nephropathy. Recent studies have suggested that autophagy activity is altered in both podocytes and proximal tubular cells under diabetic conditions. Autophagy activity is regulated by both nutrient state and intracellular stresses. Under diabetic conditions, an altered nutritional state due to nutrient excess may interfere with the autophagic response stimulated by intracellular stresses, leading to exacerbation of organelle dysfunction and diabetic nephropathy. In this review, we discuss new findings showing the relationships between autophagy and diabetic nephropathy and suggest the therapeutic potential of autophagy in diabetic nephropathy.

Treated and untreated hypertension, hospitalization, and medical expenditure: an epidemiological study in 314622 beneficiaries of the medical insurance system in Japan

OBJECTIVE

This study investigated the effect of hypertension on hospitalization risk and medical expenditure according to treatment status in a Japanese population.

METHODS

A total of 314 622 beneficiaries of the medical insurance system in Japan, aged 40-69 years, without a history of cardiovascular, cerebrovascular, or end-stage renal disease were classified into seven blood pressure categories. These categories were used to compare the risk of undergoing hospitalization in the 1 year after the baseline survey and to examine the percentage of inpatient medical expenditure attributable to overall hypertension relative to total medical expenditure in the study population.

RESULTS

During the follow-up period, 6.6% of men and 5.1% of women were hospitalized. In men and women aged 40-54 years, cases of hypertension, especially grade 3 untreated hypertension, led to more frequent hospitalization, compared with optimal blood pressure. Individuals who were hospitalized, especially long-term, incurred considerably higher medical expenditure compared with those who were not hospitalized, regardless of their hypertension status. In women aged 55-69 years, there was little variation in hospitalization risk across blood pressure categories. The inpatient medical expenditure attributable to overall hypertension represented 7.2 and 6.9% of the total medical expenditure for men aged 40-54 and 55-69 years, whereas it represented 2.8 and 3.8% for women, respectively.

CONCLUSION

Although cases of hypertension were an economic burden especially in men, grade 3 untreated hypertension was more likely to incur extremely high medical expenditure as a result of hospitalization, compared with other cases.

Patients with chronic kidney disease

Chronic kidney disease (CKD) is a major public health problem worldwide. Roughly 1 in 10 adult Americans has CKD. These patients are at significant risk for excessive morbidity and mortality during the perioperative period. Given the health and cost burden of end-stage renal disease (ESRD), preventing or avoiding progression of CKD to ESRD is critical. Therefore, identifying risk factors and implementing risk mitigation strategies to prevent further deterioration of renal function during the perioperative period is of paramount importance. This article reviews patient risk stratification, preoperative evaluation and management, and perioperative interventions for renal protection.

Obesity-mediated autophagy insufficiency exacerbates proteinuria-induced tubulointerstitial lesions

Obesity is an independent risk factor for renal dysfunction in patients with CKDs, including diabetic nephropathy, but the mechanism underlying this connection remains unclear. Autophagy is an intracellular degradation system that maintains intracellular homeostasis by removing damaged proteins and organelles, and autophagy insufficiency is associated with the pathogenesis of obesity-related diseases. We therefore examined the role of autophagy in obesity-mediated exacerbation of proteinuria-induced proximal tubular epithelial cell damage in mice and in human renal biopsy specimens. In nonobese mice, overt proteinuria, induced by intraperitoneal free fatty acid-albumin overload, led to mild tubular damage and apoptosis, and activated autophagy in proximal tubules reabsorbing urinary albumin. In contrast, diet-induced obesity suppressed proteinuria-induced autophagy and exacerbated proteinuria-induced tubular cell damage. Proximal tubule-specific autophagy-deficient mice, resulting from an Atg5 gene deletion, subjected to intraperitoneal free fatty acid-albumin overload developed severe proteinuria-induced tubular damage, suggesting that proteinuria-induced autophagy is renoprotective. Mammalian target of rapamycin (mTOR), a potent suppressor of autophagy, was activated in proximal tubules of obese mice, and treatment with an mTOR inhibitor ameliorated obesity-mediated autophagy insufficiency. Furthermore, both mTOR hyperactivation and autophagy suppression were observed in tubular cells of specimens obtained from obese patients with proteinuria. Thus, in addition to enhancing the understanding of obesity-related cell vulnerability in the kidneys, these results suggest that restoring the renoprotective action of autophagy in proximal tubules may improve renal outcomes in obese patients.

The association of chronic kidney disease complications by albuminuria and glomerular filtration rate: a cross-sectional analysis

Background: Albuminuria is strongly associated with future risk for cardiovascular and kidney outcomes, and has been proposed to be included in the classification of chronic kidney disease (CKD) along with glomerular filtration rate (GFR). Few data are available on whether albuminuria is associated with concurrent complications of CKD. Methods: A cross-sectional analysis of 1,665 participants screened for the Modification of Diet in Renal Disease (MDRD) study was performed to examine the association between albuminuria (determined using urine albumin-creatinine ratio (ACR)) and measured GFR (determined using urinary clearance of iothalamate) with anemia, acidosis, hyperphosphatemia, and hypertension. Results: Mean GFR (± SD) was 39 ml/min/1.73 m² (± 21) and the median (25 – 75^th percentile) ACR was 161 (38 – 680) mg/g. In multivariable models adjusted for age, sex, race, kidney disease etiology, and GFR, higher ACR levels were not associated with any complication. For example, comparing ACR > 300 mg/g vs. < 30 mg/g, the prevalence ratio (95% CI) for anemia was 0.98 (0.81 – 1.20), acidosis 1.13 (0.86 – 1.48), hyperphosphatemia 1.69 (0.91 – 3.17), and hypertension 1.04 (0.97 – 1.12). Lower levels of GFR were associated with all complications. For example, GFR levels < 30 ml/min/1.73 m² vs. GFR levels 60 – 89 ml/min/1.73 m² were associated with prevalence ratios (95% CI) of anemia 4.35 (3.18 – 5.96), acidosis 5.31 (3.41 – 8.29), hyperphosphatemia 23.8 (7.71 – 73.6), and hypertension 1.21 (1.10 – 1.32). Conclusions: Albuminuria is not associated with complications after controlling for GFR in patients younger than 70 years of age with non-diabetic CKD and GFR less than 90 ml/min/1.73 m² and thus would not affect clinical action plans for decisions regarding evaluation and treatment of complications in similar populations.

Antihypertensive treatment and renal protection: the role of drugs inhibiting the renin-angiotensin-aldosterone system

The prevalence of chronic kidney disease, currently estimated to vary between 8 and 12 % in the general population, is steadily rising due to aging and to the ongoing epidemic of hypertension and type 2 diabetes. Even in its early stages, chronic kidney disease entails a greater risk for cardiovascular mortality, and its prevention and treatment is rapidly becoming a key medical issue for many health care systems worldwide. Adequate blood pressure control and reduction of urine protein excretion, preferably obtained by the use of renin-angiotensin-aldosterone system inhibitors, have traditionally been considered the mainstay of therapeutic strategies in patients with renal disease. Given the pivotal role of renin-angiotensin-aldosterone system activity in the pathogenesis and progression of renal and cardiovascular damage, a more profound inhibition of the system, either by the use of multiple agents or by a single agent at high dosage has recently been advocated, especially in the presence of proteinuria. Recent trials, however have failed to confirm the usefulness of this therapeutic approach, at least in unselected patients. This article will critically review the current literature and will discuss the clinical implications of targeting the renin-angiotensin-aldosterone system in order to provide the greatest renal protection.

Estimated albumin excretion rate versus urine albumin-creatinine ratio for the estimation of measured albumin excretion rate: derivation and validation of an estimated albumin excretion rate equation

BACKGROUND

Glomerular filtration rate estimation equations use demographic variables to account for predicted differences in creatinine generation rate. In contrast, assessment of albuminuria from urine albumin-creatinine ratio (ACR) does not account for these demographic variables, potentially distorting albuminuria prevalence estimates and clinical decision making.

STUDY DESIGN

Polynomial regression was used to derive an age-, sex-, and race-based equation for estimation of urine creatinine excretion rate, suitable for use in automated estimated albumin excretion rate (eAER) reporting.

SETTING & PARTICIPANTS

The MDRD (Modification of Diet in Renal Disease) Study cohort (N=1,693) was used for equation derivation. Validation populations were the CRIC (Chronic Renal Insufficiency Cohort; N=3,645) and the DCCT (Diabetes Control and Complications Trial; N=1,179).

INDEX TEST

eAER, calculated by multiplying ACR by estimated creatinine excretion rate, and ACR.

REFERENCE TEST

Measured albumin excretion rate (mAER) from timed 24-hour urine collection.

RESULTS

eAER estimated mAER more accurately than ACR; the percentages of CRIC participants with eAER within 15% and 30% of mAER were 33% and 60%, respectively, versus 24% and 39% for ACR. Equivalent proportions in DCCT were 52% and 86% versus 15% and 38%. The median bias of ACR was -20.1% and -37.5% in CRIC and DCCT, respectively, whereas that of eAER was +3.8% and -9.7%. Performance of eAER also was more consistent across age and sex categories than ACR.

LIMITATIONS

Single timed urine specimens used for mAER, ACR, and eAER.

CONCLUSIONS

Automated eAER reporting potentially is a useful approach to improve the accuracy and consistency of clinical albuminuria assessment.

Aggressive blood pressure reduction and renin-angiotensin system blockade in chronic kidney disease: time for re-evaluation?

Over the past decades, aggressive control of blood pressure (BP) and blockade of the renin-angiotensin-aldosterone system (RAAS) were considered the cornerstones of treatment against progression of chronic kidney disease (CKD), following important background and clinical evidence on the associations of hypertension and RAAS activation with renal injury. To this end, previous recommendations included a BP target of <130/80 mm Hg for all individuals with CKD (and possibly <125/75 mm Hg for those with proteinuria >1 g/day), as well as use of angiotensin-converting-enzyme inhibitors and angiotensin receptor blockers as first-line therapy for hypertension in all CKD patients. However, long-term extensions of relevant clinical trials support a low-BP goal only for patients with proteinuria, whereas recent cardiovascular trials questioned the benefits of low systolic BP for diabetic patients, leading to more individualized recommendations. Furthermore, our previous knowledge of the specific renoprotective properties of RAAS blockers in patients with proteinuric CKD is now extended with data on the use of these agents in patients with less advanced nephropathy and/or absence of proteinuria, deriving mostly from subanalyses of cardiovascular trials. This review discusses previous and recent clinical evidence on the issues of BP reduction and RAAS blockade by type and stage of renal damage, aiming to aid clinicians in their treatment decisions for patients with CKD.

Feline CKD

Practical relevance:

Treatment of feline chronic kidney disease (CKD) tends to focus on minimising the adverse effects of reduced renal function, rather than addressing an underlying cause. Despite this, and the progressive nature of CKD, treatment can improve quality of life and enable many cats to have long survival times.

Evidence base:

Strong evidence supports the provision of renal diets, which are protein and phosphorus restricted; compliance is improved by gradual dietary transition. Additional phosphorus restriction is achieved by the use of phosphate binding agents, although it is unknown if these yield similar survival benefits to those provided by renal diets. Interventions to control hypokalaemia and hypertension in affected cats are important to prevent serious complications. Administration of benazepril to cats with proteinuric kidney disease has been shown to significantly improve their appetite but not their survival. As CKD progresses, many cats will benefit from treatment to control clinical signs of uraemic gastroenteritis and anaemia.

Effect of mononuclear cells versus pioglitazone on streptozotocin-induced diabetic nephropathy in rats

BACKGROUND

Diabetic nephropathy is a serious diabetic complication that leads to end stage renal disease. Cell therapies with human embryonic and specific adult stem cells have emerged as an alternative management for various diseases.

METHODS

To test this hypothesis, the present study was conducted to compare effect of MNCs treatment (iv injection once in the tail vein for diabetic rats in a dose of 150 x 10(6) MNCs cells/rat) versus pioglitazone (10 mg/kg, for eight weeks) on improving the renal structure and function changes and reducing laminin deposition associated with STZ-induced diabetic nephropathy in rats.

RESULTS

Treatment with pioglitazone orMNCs, demonstrated a significant improvement in the STZ-induced renal functional and structural changes in comparison with diabetic control group. Additionally, our histopathological and immunohistochemical studies confirm these results. Meanwhile, MNCs treated group exhibited more improvement in all studied parameters as compared to pioglitazone treated group.

CONCLUSION

These data indicate that MNCs treatment was superior to pioglitazone in controlling hyperglycemia, improving the renal structure and function changes and reducing renal laminin expression associated with STZ-induced diabetic nephropathy in rats.

Blood lead level and measured glomerular filtration rate in children with chronic kidney disease

BACKGROUND

The role of environmental exposure to lead as a risk factor for chronic kidney disease (CKD) and its progression remains controversial, and most studies have been limited by a lack of direct glomerular filtration rate (GFR) measurement.

OBJECTIVE

We evaluated the association between lead exposure and GFR in children with CKD.

METHODS

In this cross-sectional study, we examined the association between blood lead levels (BLLs) and GFR measured by the plasma disappearance of iohexol among 391 participants in the Chronic Kidney Disease in Children (CKiD) prospective cohort study.

RESULTS

Median BLL and GFR were 1.2 µg/dL and 44.4 mL/min per 1.73 m2, respectively. The average percent change in GFR for each 1-µg/dL increase in BLL was -2.1 (95% CI: -6.0, 1.8). In analyses stratified by CKD diagnosis, the association between BLL and GFR was stronger among children with glomerular disease underlying CKD; in this group, each 1-µg/dL increase in BLL was associated with a -12.1 (95% CI: -22.2, -1.9) percent change in GFR. In analyses stratified by anemia status, each 1-µg/dL increase in BLL among those with and without anemia was associated with a -0.3 (95% CI: -7.2, 6.6) and -4.6 (95% CI: -8.9, -0.3) percent change in GFR, respectively.

CONCLUSIONS

There was no significant association between BLL and directly measured GFR in this relatively large cohort of children with CKD, although associations were observed in some subgroups. Longitudinal analyses are needed to examine the temporal relationship between lead and GFR decline, and to further examine the impact of underlying cause of CKD and anemia/hemoglobin status among patients with CKD.

Elevated 18F-FDG levels in blood and organs after angiotensin II receptor blocker administration: experiment in mice administered telmisartan

Angiotensin II receptor blockers (ARBs) are a common treatment for hypertensive patients but affect renal function. In this study, the effects of ARB on (18)F-FDG distribution and excretion were examined in mice treated with telmisartan at different doses.

METHODS

Male C57BL/6J mice were given telmisartan (low-dose group, 0.33 mg/kg/d; moderate-dose group, 0.66 mg/kg/d; high-dose group, 3 mg/kg/d) mixed in a high-fat diet for 20 wk. Mice on a telmisartan-free diet served as the control. At designated time points, the mice were injected with (18)F-FDG (18.5 MBq/mouse, n = 5-10/time point for each group) to examine its biodistribution. Autoradiography using kidney sections was performed to visualize (18)F-FDG excretion. Plasma blood urea nitrogen (BUN) and creatinine levels were also measured to evaluate renal function.

RESULTS

Twenty-week telmisartan treatment significantly and dose-dependently increased (18)F-FDG levels in the blood (percentage injected dose per gram of tissue normalized by animal body weight: low, 0.13 ± 0.03 [P < 0.0083]; moderate, 0.15 ± 0.01 [P < 0.0083]; high, 0.15 ± 0.03 [P < 0.0083], vs. control, 0.09 ± 0.01). Significantly increased (18)F-FDG levels in organs were observed in mice in the moderate- and high-dose groups but not in the low-dose group. The plasma BUN and creatinine levels also dose-dependently increased, but they were within the reference ranges (for BUN: low, 27.00 ± 4.42 mg/dL; moderate, 28.40 ± 2.70 mg/dL; high, 39.22 ± 6.91 mg/dL [P < 0.0083], vs. control, 22.40 ± 2.80 mg/dL. For creatinine: low, 0.28 ± 0.11 mg/dL; moderate, 0.40 ± 0.07 mg/dL [P < 0.0083]; high, 0.51 ± 0.09 mg/dL [P < 0.0083], vs. control, 0.18 ± 0.04 mg/dL). The blood (18)F-FDG level positively correlated with plasma BUN (r = 0.48, P < 0.01) and creatinine (r = 0.61, P < 0.01) levels. The (18)F-FDG levels in the blood and organs returned to baseline 3 wk after cessation of telmisartan treatment. Autoradiography indicated that renal (18)F-FDG excretion was attenuated by telmisartan treatment and was reversed after treatment cessation.

CONCLUSION

(18)F-FDG levels in the blood and organs were significantly increased by telmisartan treatment, indicating a potential increase in background activity on PET imaging of patients treated with ARBs. Our findings indicate the need for a careful assessment of (18)F-FDG uptake in patients treated with ARBs. A brief cessation of ARB treatment may be a potential method to avoid these effects and solve this problem.

Effects of intensive blood pressure lowering on the progression of chronic kidney disease: a systematic review and meta-analysis

BACKGROUND

Recent guidelines suggest lowering the target blood pressure for patients with chronic kidney disease, although the strength of evidence for this suggestion has been uncertain. We sought to assess the renal and cardiovascular effects of intensive blood pressure lowering in people with chronic kidney disease.

METHODS

We performed a systematic review and meta-analysis of all relevant reports published between 1950 and July 2011 identified in a search of MEDLINE, Embase and the Cochrane Library. We included randomized trials that assigned patients with chronic kidney disease to different target blood pressure levels and reported kidney failure or cardiovascular events. Two reviewers independently identified relevant articles and extracted data.

RESULTS

We identified 11 trials providing information on 9287 patients with chronic kidney disease and 1264 kidney failure events (defined as either a composite of doubling of serum creatinine level and 50% decline in glomerular filtration rate, or end-stage kidney disease). Compared with standard regimens, a more intensive blood pressure-lowering strategy reduced the risk of the composite outcome (hazard ratio [HR] 0.82, 95% confidence interval [CI] 0.68-0.98) and end-stage kidney disease (HR 0.79, 95% CI 0.67-0.93). Subgroup analysis showed effect modification by baseline proteinuria (p = 0.006) and markers of trial quality. Intensive blood pressure lowering reduced the risk of kidney failure (HR 0.73, 95% CI 0.62-0.86), but not in patients without proteinuria at baseline (HR 1.12, 95% CI 0.67-1.87). There was no clear effect on the risk of cardiovascular events or death.

INTERPRETATION

Intensive blood pressure lowering appears to provide protection against kidney failure events in patients with chronic kidney disease, particularly among those with proteinuria. More data are required to determine the effects of such a strategy among patients without proteinuria.

Pharmacologic treatment of hypertension in patients with chronic kidney disease

Hypertension remains an important cause of morbidity and mortality in patients with chronic kidney disease. It both contributes to and is a consequence of chronic renal dysfunction. There is a high prevalence of hypertension in chronic kidney disease, and rates of control remain sub-optimal. Numerous studies have highlighted the benefit of treating hypertension in reducing the overall mortality as well as progression of renal disease in this population. Non-pharmacologic treatment strategies remain the primary intervention in all patients but are insufficient on their own to control hypertension in most cases. Pharmacologic treatment recommendations, however, vary depending on the specific etiology of disease as well as patient characteristics. Though most classes of anti-hypertensive drugs can be used to lower blood pressure in chronic kidney disease, therapy needs to be selected based on the presence of specific co-morbidities as well as the etiology of the kidney disease. Most patients will require multi-drug therapy for achieving target blood pressure goals. This review discusses the pharmacologic options in management of hypertension in various forms of chronic kidney disease.

Proteinuria as a risk factor for decline in residual renal function in non-diabetic peritoneal dialysis patients

BACKGROUND

Preservation of residual renal function (RRF) is a major issue for patients on peritoneal dialysis (PD). Whether proteinuria is associated with a decline in RRF in patients on PD remains unclear.

PATIENTS AND METHODS

We reviewed the medical records at the Yeungnam University Hospital in Korea and identified patients who started PD between June 1995 and August 2011. A total of 147 non-diabetic patients were enrolled in the study. The patients were divided into 3 groups with respect to the tertile of initial proteinuria level: Low (n = 49; <320 mg/day), Middle (n = 49; 320-822 mg/day), and High groups (n = 49; >822 mg/day).

RESULTS

The mean patient age was 50.2 ± 15.0 years in the Low tertile, 50.2 ± 15.4 years in the Middle tertile, and 49.0 ± 15.1 years in the High tertile. Decline in RRF during follow-up period was greater in the High tertile than that in the other tertiles (P = 0.001). The proportion of patients with RRF >50% of baseline at 24 months after the initiation of PD was 83% in the Low tertile, 66% in the Middle tertile, and 40% in the High tertile (P < 0.001). The multivariate analysis after adjusting for initial RRF, age, gender, underlying disease of end-stage renal disease except diabetes mellitus, PD modality, use of icodextrin, PD-associated peritonitis, and tertile of the initial proteinuria level revealed that High tertile of the initial proteinuria level was associated with a decline in RRF (hazard ratios: 2.442 for the Middle tertile, P = 0.007 ; 3.713 for the Low tertile, P < 0.001).

CONCLUSION

The present study demonstrates that proteinuria may be is associated with a rapid decline in RRF in non-diabetic patients on PD, although the potential role of additional factors should be further investigated in prospective studies.

Blood pressure, proteinuria, and phosphate as risk factors for progressive kidney disease: a hypothesis

Chronic kidney disease (CKD) affects approximately 500 million people worldwide and is increasingly common in both industrialized and emerging countries. Although the mechanisms underlying the inexorable progression of CKD are incompletely defined, recent discoveries may pave the way to a more comprehensive understanding of the pathophysiology of CKD progression and the development of new therapeutic strategies. In particular, there is accumulating evidence indicating a key role for the complex and yet incompletely understood system of divalent cation regulation, which includes phosphate metabolism and the recently discovered fibroblast growth factor 23 (FGF-23)/klotho system, which seems inextricably associated with vitamin D deficiency. The aim of this review is to discuss the links between high blood pressure, proteinuria, phosphate levels, and CKD progression and explore new therapeutic strategies to win the fight against CKD.

What is the ideal blood pressure goal for patients with diabetes mellitus and nephropathy?

There appears to be a broad consensus among professional health organizations that a blood pressure (BP) of 130/80 mm Hg or less is the recommended therapeutic BP target for subjects with diabetes mellitus. This review focuses on key studies that have examined the relationship between BP reduction and its impact on diabetic complications. An attempt is being made to identify the BP level at which maximum protection against diabetic complications is conferred, and below which further reduction no longer delivers a benefit that exceeds risk. Specific attention has been accorded to data contributing to establishing ideal BP goals in diabetic patients with nephropathy. On the basis of recent studies, it would appear that a BP below 140/90 mm Hg should be recommended for all diabetic individuals, and around 135/85 mm Hg for most. BP should be closer to, but not below, 130/80 mm Hg for those subjects at the highest cardiovascular risk. For those diabetic subjects at highest risk for stroke, lower BP may provide greater protection against stroke as shown in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial. In younger individuals with diabetes and hypertension of shorter duration, it may be possible to lower BP below 130/80 mm Hg without untoward side effects and in fact with cardiovascular benefit, but this remains to be demonstrated. The ideal BP goal in diabetic patients with nephropathy remains questionable, and for now, the recommended target must be considered the same as that for the general diabetic population.

Is there benefit in dual renin-angiotensin-aldosterone system blockade? No, yes and maybe: a guide for the perplexed

Since the initial discovery of Angiotensin converting enzyme inhibitors (ACEI) in the 1960s and the launch of Captopril as the first available for clinical use in the 1970s, there now exist three other classes of drugs that block the renin angiotensin aldosterone system (RAAS): the angiotensin II receptor blockers (ARB), aldosterone antagonists (AA) and direct renin inhibitors (DRI). With the proven efficacy of RAAS blockers as monotherapy in many arenas there has been considerable interest in the use of dual therapy combinations of these medications that target different points in the pathway. By potentially offering a more complete RAAS blockade with a commensurate enhanced clinical effect, the strong biological rationale for dual therapy has led to it being embraced by clinicians as a treatment option, for hypertension and nephroprotection in particular. However, the initial enthusiasm for this treatment has been tempered by the recent results from several large trials such as ONTARGET and ALTITUDE, which do not support a specific dual therapy approach. In contrast, there is supportive evidence for dual blockade of specific combinations in selected patient groups and data are lacking for others. In the wake of this complex contemporary evidence, the conundrum now faced by clinicians committed to individualised care is, for which patients dual therapy could still be of benefit. This review examines for the practising clinician the current 'state of play' for dual blockade of various combinations and a perspective on its use in cardio-renal disease and diabetic complications.

Ethnic differences in the association between blood pressure components and chronic kidney disease in middle aged and older Asian adults

Background

Chronic kidney disease (CKD) is an emerging public health problem worldwide. Previous studies have shown an association between blood pressure (BP) and CKD. However, it is not clear if there are ethnic differences in this association. We examined the association between BP and CKD in a multi-ethnic Asian population in Singapore.

Methods

We analysed data from three large population-based studies conducted between 2004–2011, (n=3,167 Chinese, 3,082 Malays and 3,228 Indians) aged 40–80 years. CKD was defined as an estimated glomerular filtration rate <60 mL/min/1.73m² from serum creatinine. Hypertension was defined as a self-reported current use of antihypertensive medication or systolic BP ≥140 mm Hg or diastolic BP ≥90 mm Hg. We also analysed the association of CKD with individual BP components.

Results

The prevalence of both hypertension and CKD was higher among Malays (68.6, 21%) compared to Chinese (57.9, 5.9%) and Indians (56.0, 7.4%), but treatment for hypertension was lower among Malays (53.4%) compared to Chinese (89.8%) and Indians (83.1%). Hypertension was associated with CKD in all three ethnic groups (OR [95% CI] = 2.71 [1.59-4.63], 2.08 [1.62-2.68], 2.43 [1.66-3.57] in Chinese, Malays and Indians). Among the BP components, both systolic and diastolic BP were associated with CKD in Malays whereas, systolic BP was not significantly associated with CKD, and diastolic BP showed an inverse association which was explained by anti-hypertensive medication use in Chinese and Indians.

Conclusions

Hypertension was associated with CKD in Chinese, Malays and Indians. However, the BP components were associated with CKD only in Malays.

Incidence and risk of hypertension with vandetanib in cancer patients: a systematic review and meta-analysis of clinical trials

AIM

To perform a systematic review and meta-analysis of published clinical trials to determine incidence rate and overall risk of hypertension with vandetanib in cancer patients.

METHODS

A comprehensive literature search for studies published up to March 2012 was performed. Summary incidence rates, relative risk (RR), and 95% confidence intervals (CI) were calculated employing fixed- or random-effects models depending on the heterogeneity of the included trials.

RESULTS

A total of 11 trials with 3154 patients were included for the meta-analysis. The summary incidences of all-grade and high-grade hypertension in patients with cancer were 24.2% [95% confidence interval (CI), 18.1-30.2%] and 6.4% (95% CI, 3.3-9.5%), respectively. Subgroup analysis demonstrated that the pooled incidences of all-grade and high-grade hypertension were 21.8% [95% CI, 15-30.5%] and 7.6% (95% CI, 2.8-18.8%), respectively, among non-small-cell lung cancer (NSCLC) patients, and 32.1% (95% CI: 27.3-37.3%) and 8.8% (5.9%-12.9%), respectively, among MTC patients, and 15.4 (95% CI: 3.2-33.7%) and 3.4% (95% CI: 1%-11.1%) respectively, among non-MTC/NSCLC tumors patients. Furthermore, vandetanib was associated with a significant increased risk of all-grade hypertension (RR 5.1, 95% CI: 3.76-6.92, P = 0.000) and high-grade hypertension (RR 8.06, 95% CI: 3.41-19.04, P = 0.000) in comparison with controls.

CONCLUSIONS

There is a significant risk of developing hypertension in cancer patients receiving vandetanib. Appropriate monitoring and treatment is strongly recommended to prevent cardiovascular complications.

Renin-angiotensin system, hypertension, and chronic kidney disease: pharmacogenetic implications

About 80% of CKD (chronic kidney disease) patients are hypertensive, and kidney function and blood pressure are clearly related to both physiologic and pathologic conditions in a "vicious cycle". In this pathologic scenario, there is a renin-angiotensin system (RAS) hyperactivity associated to progression of renal damage. Current guidelines indicate as the first choice of antihypertensive intervention, the pharmacologic blockade of the RAS. Nonetheless, both response to treatment and renal protection have considerable inter-individual variability. The main aims of this review are to describe the genetic characteristics of RAS components and to identify the possible pharmacogenetic implications for RAS-blocker drugs in the hypertension-CKD scenario. To date, RAS polymorphisms have not been consistently associated to antihypertensive response and studies focusing on CKD are scarce. Nonetheless, pharmacogenetic studies for the RAS-blocker drugs could still be further explored, especially with new generation tools and focusing not only on the antihypertensive response, but also on renal protection as well.

Abnormal high-density lipoprotein induces endothelial dysfunction via activation of Toll-like receptor-2

Endothelial injury and dysfunction (ED) represent a link between cardiovascular risk factors promoting hypertension and atherosclerosis, the leading cause of death in Western populations. High-density lipoprotein (HDL) is considered antiatherogenic and known to prevent ED. Using HDL from children and adults with chronic kidney dysfunction (HDL(CKD)), a population with high cardiovascular risk, we have demonstrated that HDL(CKD) in contrast to HDL(Healthy) promoted endothelial superoxide production, substantially reduced nitric oxide (NO) bioavailability, and subsequently increased arterial blood pressure (ABP). We have identified symmetric dimethylarginine (SDMA) in HDL(CKD) that causes transformation from physiological HDL into an abnormal lipoprotein inducing ED. Furthermore, we report that HDL(CKD) reduced endothelial NO availability via toll-like receptor-2 (TLR-2), leading to impaired endothelial repair, increased proinflammatory activation, and ABP. These data demonstrate how SDMA can modify the HDL particle to mimic a damage-associated molecular pattern that activates TLR-2 via a TLR-1- or TLR-6-coreceptor-independent pathway, linking abnormal HDL to innate immunity, ED, and hypertension.

Hypertension and kidney disease: what do the data really show?

Hypertension is the most common co-morbidity in chronic kidney disease (CKD) and the optimal target BP to prevent CKD progression has been hotly debated. Prior recommendations by various groups for BP targets for CKD in the range of less than 130/80 mm Hg have been based on the assumed benefits of lower BP in this population with exceedingly high risk for cardiovascular disease (CVD). Although there is suggestive data that lower BP may be helpful in patients with proteinuria and CKD, studies not directly link a treatment-related reduction in proteinuria to a benefit in kidney outcomes. There are ongoing studies which will provide more data on BP targets in CKD. Based on the currently available data we recommend a BP goal of less than 140/90 mm Hg in all patients with CKD.

Managing cardiovascular risk in people with chronic kidney disease: a review of the evidence from randomized controlled trials

Cardiovascular disease is the leading cause of death and morbidity in people with chronic kidney disease (CKD) making measures to modify cardiovascular risk a clinical priority. The relationship between risk factors and cardiovascular outcomes is often substantially different in people with CKD compared with the general population, leading to uncertainty around pathophysiological mechanisms and the validity of generalizations from the general population. Furthermore, published reports of subgroup analyses from clinical trials have suggested that a range of interventions may have different effects in people with kidney disease compared with those with normal kidney function. There is a relative scarcity of randomized controlled trials (RCTs) conducted in CKD populations, and most such trials are small and underpowered. As a result, evidence to support cardiovascular risk modification measures for people with CKD is largely derived from small trials and post hoc analyses of RCTs conducted in the general population. In this review, we examine the available RCT evidence on interventions aimed at preventing cardiovascular events in people with kidney disease to identify beneficial treatments as well as current gaps in knowledge that should be a priority for future research.

Impact of heavy proteinuria on clinical outcomes in patients on incident peritoneal dialysis

Background

There are few reports on the nutritional status changes and residual renal function (RRF) according to proteinuria levels in patients on peritoneal dialysis (PD).

Methods

A total of 388 patients on PD were enrolled. The patients were divided into 3 groups with respect to initial proteinuria: the A (n = 119; <500 mg/day), B (n = 218; 500–3,500 mg/day), and C groups (n = 51; >3,500 mg/day).

Results

The patients with higher proteinuria levels had a higher incidence of male sex, diabetes mellitus, and icodextrin use than those with lower proteinuria levels. Although initial peritoneal albumin loss in C group was lower than that detected in the other groups, no significant difference was observed in peritoneal albumin loss among the 3 groups at the end of follow-up period. At the time of PD initiation, the Geriatric nutritional risk index (GNRI) was lower in the C group than in the other 2 groups. However, at the end of the follow-up period, there was no significant difference in GNRI between the 3 groups. The GNRI increased, and the proteinuria level or RRF decreased more in the C group than in the other 2 groups. There were no significant differences in lean mass index or fat mass index change from the time of PD initiation to the end of the follow-up period. However, fat mass index and nPNA showed greater increases in the C group. The multivariate analysis revealed that proteinuria was negatively correlated with GNRI at the time of PD initiation and at the end of the follow-up period. The initial RRF and proteinuria were negatively correlated with the RRF decline during the follow-up.

Conclusion

The attenuation of the nephrotic proteinuria, along with the RRF decline, was associated with the improvement of the malnutrition.

Influence of renin angiotensin system gene polymorphisms on visit-to-visit blood pressure variability in hypertensive patients

BACKGROUND

Visit-to-visit blood pressure (BP) variability has been reported to be a major risk for cardiovascular events. Renin angiotensin system (RAS) gene polymorphisms are reportedly genetic risk factors for cardiovascular diseases and arterial stiffness. In this study, we aimed to reveal the relationship between visit-to-visit BP variability and RAS gene polymorphisms.

METHODS

Study subjects included 427 essential hypertension patients from the Non-Invasive Atherosclerotic Evaluation in Hypertension study cohort, whose BP was measured during at least six outpatient visits. We analyzed the correlation between visit-to-visit variability in systolic BP (SBP) and RAS gene polymorphisms.

RESULTS

We identified angiotensinogen M235T, angiotensin II type 1 receptor A1166C, and angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphisms. Only ACE I/D polymorphisms were correlated with variability in diastolic BP; no gene polymorphisms were correlated with variability in SBP.

CONCLUSIONS

RAS gene polymorphisms, especially ACE I/D polymorphisms, might genetically influence the visit-to-visit BP variability in hypertensive patients.

Can vitamin D slow down the progression of chronic kidney disease?

Pharmacological blockade of the renin-angiotensin-aldosterone system (RAAS) is the cornerstone of renoprotective therapy, and the reduction of persistent RAAS activation is considered to be an important target in the treatment of chronic kidney disease (CKD). Vitamin D is a steroid hormone that controls a broad range of metabolic and cell regulatory functions. It acts as a transcription factor and can suppress the renin gene, thereby acting as a negative endocrine regulator of RAAS. RAAS activation can reduce renal Klotho expression, and the Klotho-fibroblast growth factor 23 interaction may further reduce the production of active vitamin D. Results from both clinical and experimental studies suggest that vitamin D therapy is associated with a reduction in blood pressure and left ventricular hypertrophy and improves cardiovascular outcomes. In addition, a reduction in angiotensin II through RAAS blockade may have anti-proteinuric and anti-fibrotic effects. Vitamin D has also been shown to modulate the immune system, regulate inflammatory responses, improve insulin sensitivity and reduce high-density lipoprotein cholesterol. Taken together, these pleiotropic effects of vitamin D may slow down the progression of CKD. In this review, we discuss the experimental and early clinical findings that suggest a renoprotective effect of vitamin D, thereby providing an additional rationale beyond mineral metabolism for the close monitoring of, and supplementation with vitamin D from the earliest stages of CKD.

Incidence and risk of hypertension with pazopanib in patients with cancer: a meta-analysis

PURPOSES

To gain a better understanding of the overall incidence and risk of hypertension in cancer patients who receive pazopanib and to compare the differences in incidence among sorafenib, sunitinib, and pazopanib.

METHODS

Several databases were searched, including PubMed, Embase, and Cochrane databases. Eligible studies were phase II and III prospective clinical trials of patients with cancer assigned single drug pazopanib 800 mg/day with data on hypertension available. Overall incidence rates, relative risk (RR), and 95 % confidence intervals (CI) were calculated employing fixed or random effects models depending on the heterogeneity of the included trials.

RESULTS

A total of 1,651 patients with a variety of solid tumors from 13 clinical trials were included for the meta-analysis. The overall incidences of all-grade and high-grade hypertension in cancer patients were 35.9 % (95 % CI 31.5-40.6 %) and 6.5 % (95 % CI 5.2-8.0 %), respectively. The use of pazopanib was associated with an increased risk of developing all-grade (RR 4.97, 95 % CI 3.38-7.30, p < 0.001) and high-grade hypertension (RR 2.87, 95 % CI 1.16-7.12, p = 0.023). Additionally, there was no significant difference in the incidence of all-grade (RR 1.21, 95 % CI 0.96-1.53, p = 0.11) and high-grade hypertension (RR 1.29, 95 % CI 0.80-2.07, p = 0.30) between RCC and non-RCC patients. Interestingly, the risk of all-grade hypertension with pazopanib was substantially higher than sorafenib (RR 1.99; 95 % CI 1.73-2.29, p = 0.00) and sunitinib (RR 2.20; 95 % CI 1.92-2.52, p = 0.00), while the risk of pazopanib-induced high-grade hypertension was similar to sorafenib (RR 0.98; 95 % CI 0.75-1.30, p = 0.90) and sunitinib (RR 0.81; 95 % CI 0.62-1.06, p = 0.12).

CONCLUSIONS

The use of pazopanib is associated with a significantly increased risk of developing hypertension. Close monitoring and appropriate managements are recommended during the therapy. Future studies are still needed to investigate the risk reduction and possible use of pazopanib in selected patients.