Chronic Kidney Disease

Deciphering the genetic and modular connections between coronary heart disease, idiopathic pulmonary arterial hypertension and pulmonary heart disease

Coronary heart disease (CHD), idiopathic pulmonary arterial hypertension (IPAH) and pulmonary heart disease (PHD) are circulatory system diseases that may simultaneously emerge in a patient and they are often treated together in clinical practice. However, the molecular mechanisms connecting these three diseases remain unclear. In order to determine the multidimensional characteristic correlations between these three diseases based on genomic networks to aid in medical decision-making, genes from the Online Mendelian Inheritance in Man database were obtained, and applied network construction and modularized analysis were conducted. Functional enrichment analysis was conducted to explore the associations between overlapping genes, modules and pathways. A total of 29 overlapping genes and 3 common modules were identifed for the 3 diseases. Glycosphingolipid biosynthesis and the arachidonic acid metabolism are common pathways, and the biosynthetic process is suggested to be the major function involved in the three diseases. The current study reported, to the best of our knowledge for the first time, the role of glycosphingolipid biosynthesis in IPAH and PHD. The present study provided an improved understanding of the pathological mechanisms underlying CHD, IPAH and PHD. The overlapping genes, modules and pathways suggest novel areas for further research, and drug targets. The observations of the current study additionally suggest that drug indications can be broadened because of the presence of common targets.

Renal function and effect of statin therapy on cardiovascular outcomes in patients undergoing coronary revascularization (from the CREDO-Kyoto PCI/CABG Registry Cohort-2)

Although statin therapy is essential for secondary cardiovascular prevention, the therapeutic effect of statins on cardiovascular outcomes in patients with advanced chronic kidney disease (CKD) after coronary revascularization has not been fully elucidated. In the CREDO-Kyoto Registry Cohort-2, 14,706 patients who underwent first coronary revascularization were divided into 4 strata based on estimated glomerular filtration rate (eGFR) or status of hemodialysis (HD). Patients in each stratum were further divided into 2 groups based on statin therapy at discharge: non-CKD stratum (eGFR ≥60 ml/min/1.73 m(2)), 8,959 patients (statin, n = 4,747; no statin, n = 4,212); mild CKD stratum (eGFR ≥30 to <60 ml/min/1.73 m(2)), 4,567 patients (statin, n = 2,135; no statin, n = 2,432); severe CKD stratum (eGFR <30 ml/min/1.73 m(2)), 608 patients (statin, n = 229; no statin, n = 379); and HD stratum, 572 patients (statin, n = 117; no statin, n = 455). Median follow-up duration was 956 days (interquartile range 699 to 1,245). Adjusted risk for major adverse cardiovascular events (MACEs; composite of cardiovascular death, myocardial infarction, or stoke) was significantly lower in the statin group than in the no-statin group in the non-CKD (hazard ratio 0.8, 95% confidence interval 0.68 to 0.95, p = 0.01) and mild CKD (hazard ratio 0.69, 95% confidence interval 0.56 to 0.84, p = 0.0002) strata. However, a significant association of statin therapy and lower risk for MACEs was not seen in the severe CKD (hazard ratio 0.91, 95% confidence interval 0.6 to 1.38, p = 0.65) and HD (hazard ratio 1.04, 95% confidence interval 0.64 to 1.69, p = 0.87) strata. In conclusion, statin therapy was associated with significantly lower risk for MACEs in patients with non-CKD and mild CKD undergoing coronary revascularization. However, therapeutic benefits of statins were not apparent in patients with severe CKD and HD.

Diagnosis of cardiovascular disease in patients with chronic kidney disease

The major forms of cardiovascular disease including coronary atherosclerosis, valvular disease, myocardial dysfunction, and arrhythmias are observed either alone or in combination in a large fraction of patients with chronic kidney disease (CKD). As CKD progresses, these cardiovascular conditions become more prevalent and severe. The clinical implications of combined heart and kidney disease include challenges in diagnosis and management. In addition, the terminal events in CKD commonly involve one of these four domains of cardiovascular disease. This paper will explore the issue of early diagnosis of heart disease in patients with CKD with the major goal being early intervention to lessen the impact of this comorbidity.

Long-term effects of fosinopril and pravastatin on cardiovascular events in subjects with microalbuminuria:Ten years of follow-up of Prevention of Renal and Vascular End-stage Disease Intervention Trial (PREVEND IT)

BACKGROUND

The PREVEND IT investigated whether treatment targeted at lowering urinary albumin excretion (UAE) would reduce adverse cardiovascular events. We obtained extended follow-up data to approximately 10 years to investigate the long-term effects of fosinopril 20 mg and pravastatin 40 mg on cardiovascular outcomes in subjects with UAE >15 mg per 24 hours.

METHODS

The original PREVEND IT consisted of 864 participants and 839 survivors after 4 years. For every survivor, the primary end point determined by the combined incidence of cardiovascular mortality and hospitalization for cardiovascular morbidity was registered in several national databases and electronic hospital systems.

RESULTS

Mean total follow-up of the extended PREVEND IT was 9.5 years (range 9.4-10.7 years). Four years of treatment with fosinopril was not associated with a reduction in the primary end point compared with placebo (hazard ratio 0.87, 95% CI 0.61-1.24 [P = .42]) during long-term follow-up. After 9.5 years, subjects with a baseline UAE in the upper quintile (>50 mg/24 hours) had a total event rate of 29.5% and were at a higher risk for developing cardiovascular disease compared with less UAE (hazard ratio 2.03, 95% CI 1.38-2.97 [P ≤ .01]). In addition, 4 years of fosinopril treatment resulted in a risk reduction of 45% (95% CI 6%-75% [P = .04]) in this group compared with placebo. Subjects originally assigned to pravastatin had no overall risk reduction in the primary end point (P = .99).

CONCLUSIONS

Elevated UAE is associated with increased cardiovascular mortality and morbidity after 9.5 years of follow-up, with a doubling of the risk if the UAE is >50 mg per 24 hours. In this group, the benefits of 4-year treatment with fosinopril were sustained during posttrial follow-up for cardiovascular mortality and morbidity. We propose that UAE be used to estimate risk in the general population and that large clinical trials be designed to confirm the hypothesis that angiotensin-converting enzyme-inhibitor treatment may be beneficial in patients with mildly elevated UAE despite the absence of other comorbidities.

Cardiorenal syndromes

Cardiorenal syndromes (CRS) have been subclassified as five defined entities which represent clinical circumstances in which both the heart and the kidney are involved in a bidirectional injury and dysfunction via a final common pathway of cell-to-cell death and accelerated apoptosis mediated by oxidative stress. Types 1 and 2 involve acute and chronic cardiovascular disease (CVD) scenarios leading to acute kidney injury or accelerated chronic kidney disease. Types 2 and 3 describe acute and chronic kidney disease leading primarily to heart failure, although it is possible that acute coronary syndromes, stroke, and arrhythmias could be CVD outcomes in these forms of CRS. Finally, CRS type 5 describes a simultaneous insult to both heart and kidneys, such as sepsis, where both organs are injured simultaneously. Both blood and urine biomarkers are reviewed in this paper and offer a considerable opportunity to enhance the understanding of the pathophysiology and known epidemiology of these recently defined syndromes.

Cardiorenal syndromes: pathophysiology to prevention

There is a strong association between both acute and chronic dysfunction of the heart and kidneys with respect to morbidity and mortality. The complex interrelationships of longitudinal changes in both organ systems have been difficult to describe and fully understand due to a lack of categorization of the common clinical scenarios where these phenomena are encountered. Thus, cardiorenal syndromes (CRSs) have been subdivided into five syndromes which represent clinical vignettes in which both the heart and the kidney are involved in bidirectional injury and dysfunction via a final common pathway of cell-to-cell death and accelerated apoptosis mediated by oxidative stress. Types 1 and 2 involve acute and chronic cardiovascular disease (CVD) scenarios leading to acute kidney injury (AKI) or accelerated chronic kidney disease (CKD). Types 3 and 4 describe AKI and CKD, respectively, leading primarily to heart failure, although it is possible that acute coronary syndromes, stroke, and arrhythmias could be CVD outcomes in these forms of CRS. Finally, CRSs type 5 describe a systemic insult to both heart and the kidneys, such as sepsis, where both organs are injured simultaneously in persons with previously normal heart and kidney function at baseline. Both blood and urine biomarkers, including the assessment of catalytic iron, a critical element to the generation of oxygen-free radicals and oxidative stress, are reviewed in this paper.