Atherosclerosis: Open Access
Open Access

Chronic kidney disease (CKD); Atherosclerosis; Cardiovascular disease; Endothelial dysfunction; Vascular calcification; Hypertension; Dyslipidemia; Inflammation; Oxidative stress; Renal perfusion; CKD progression; Cardiovascular risk; Integrated management; Therapeutic approaches; Multidisciplinary care

Introduction

Chronic kidney disease (CKD) is a growing public health concern, affecting an estimated 10-15% of the global population. As CKD progresses, the risk of cardiovascular disease (CVD), particularly atherosclerosis, significantly increases, making cardiovascular complications the leading cause of death among CKD patients. Atherosclerosis, characterized by the accumulation of lipid-laden plaques in the arterial walls, leads to progressive narrowing and stiffening of blood vessels. This not only compromises cardiovascular health but also accelerates kidney damage due to reduced renal perfusion and ischemic injury [1].

The link between CKD and atherosclerosis is multifactorial, driven by overlapping risk factors such as hypertension, diabetes, dyslipidemia, and systemic inflammation. CKD patients often exhibit elevated markers of oxidative stress and endothelial dysfunction, both of which are key contributors to the initiation and progression of atherosclerotic lesions. Additionally, CKD is associated with disturbances in calcium-phosphate metabolism, which leads to vascular calcification, further exacerbating the atherosclerotic process.

Despite the clear association between CKD and atherosclerosis, their coexistence presents significant challenges in management. Traditional cardiovascular risk factors often manifest earlier and more severely in CKD patients, requiring tailored therapeutic strategies to address both renal and vascular health. Early detection, comprehensive risk factor modification, and collaborative care between nephrologists and cardiologists are critical in mitigating the progression of both conditions and improving patient outcomes [2].

Overview of Chronic Kidney Disease (CKD) and Atherosclerosis

Definition and epidemiology

Chronic Kidney Disease (CKD) is defined as a progressive loss of kidney function over time, with the estimated glomerular filtration rate (eGFR) as a key marker. Atherosclerosis is the buildup of plaques in arterial walls, leading to vessel narrowing and reduced blood flow. Globally, CKD affects 10-15% of adults, while atherosclerosis remains the leading cause of cardiovascular disease (CVD), affecting millions worldwide. The coexistence of CKD and atherosclerosis is common, especially among aging populations and those with comorbidities like diabetes and hypertension [3].

The burden of coexisting CKD and atherosclerosis

The co-occurrence of CKD and atherosclerosis greatly increases cardiovascular morbidity and mortality. Patients with CKD are 10-30 times more likely to die from cardiovascular complications than progress to end-stage renal disease (ESRD). The presence of both conditions worsens clinical outcomes and presents significant healthcare challenges, necessitating integrated care strategies.

Pathophysiological Mechanisms Linking CKD and Atherosclerosis

Endothelial dysfunction

Endothelial dysfunction, characterized by impaired vasodilation and increased vascular permeability, is a cornerstone in the development of both CKD and atherosclerosis. In CKD, uremic toxins and oxidative stress impair endothelial function, accelerating the formation of atherosclerotic plaques. Reduced nitric oxide bioavailability further exacerbates vascular stiffness and inflammation [4].

Oxidative stress and inflammation

Oxidative stress and chronic inflammation are central to the pathogenesis of both CKD and atherosclerosis. In CKD, the accumulation of reactive oxygen species (ROS) leads to oxidative damage of vascular cells, promoting inflammation and plaque formation. Similarly, systemic inflammation drives atherogenesis by increasing the production of pro-inflammatory cytokines and promoting monocyte adhesion to endothelial cells. Dyslipidemia is a hallmark of both CKD and atherosclerosis. In CKD, altered lipid metabolism leads to elevated triglycerides, decreased high-density lipoprotein (HDL), and small, dense low-density lipoprotein (LDL) particles, which are more atherogenic. These lipid abnormalities promote plaque formation and progression, particularly in patients with advanced kidney disease [5].

Vascular calcification and mineral metabolism in CKD

Vascular calcification, driven by disrupted calcium-phosphate metabolism, is a unique feature of CKD-related atherosclerosis. Hyperphosphatemia and elevated parathyroid hormone (PTH) levels contribute to the deposition of calcium in arterial walls, leading to stiffened vessels and increased cardiovascular risk. This process is more severe in CKD patients due to the altered balance of mineral regulators.

Shared Risk Factors for CKD and Atherosclerosis

Hypertension

Hypertension is a major risk factor for both CKD and atherosclerosis. Chronic high blood pressure damages both the kidneys and blood vessels, leading to further endothelial dysfunction and plaque formation. It also accelerates the progression of CKD by increasing glomerular pressure and promoting ischemia [6].

Diabetes mellitus

Diabetes significantly increases the risk of both CKD and atherosclerosis. Hyperglycemia leads to the formation of advanced glycation end-products (AGEs), which damage vascular structures and renal tissue. This accelerates the development of diabetic nephropathy and atherosclerotic plaque formation. Dyslipidemia, as mentioned earlier, plays a pivotal role in both CKD progression and atherosclerosis. The altered lipid profiles seen in CKD patients make them more susceptible to cardiovascular events. Managing dyslipidemia is crucial to mitigate the effects of atherosclerosis in these patients. Smoking, along with other lifestyle factors such as poor diet, physical inactivity, and obesity, is a modifiable risk factor for both CKD and atherosclerosis. Smoking exacerbates endothelial dysfunction and oxidative stress, while sedentary behavior and unhealthy diets contribute to obesity, hypertension, and dyslipidemia, increasing the risk for both conditions [7].

Clinical Implications of CKD and Atherosclerosis

Cardiovascular morbidity and mortality in CKD

CKD patients face a significantly higher risk of cardiovascular events due to the combined effects of renal impairment and atherosclerosis. Cardiovascular disease accounts for over 50% of deaths in CKD patients, underscoring the critical need for early risk stratification and intervention. Atherosclerosis in the renal arteries can lead to ischemic nephropathy, further impairing renal function and accelerating CKD progression. Reduced renal perfusion due to atherosclerosis worsens kidney damage, creating a vicious cycle of declining renal and cardiovascular health. The prognosis for patients with coexisting CKD and atherosclerosis is poor, with higher rates of complications such as heart failure, myocardial infarction, stroke, and ESRD. These complications severely limit life expectancy and quality of life, especially if both conditions are not effectively managed.

Diagnostic Approaches

Laboratory markers of CKD and cardiovascular risk

Common laboratory markers for CKD include serum creatinine, eGFR, and proteinuria, while cardiovascular risk is assessed through lipid profiles, C-reactive protein (CRP), and inflammatory markers. Monitoring these markers can help in early detection and risk stratification. Imaging techniques such as coronary artery calcium (CAC) scoring, carotid intima-media thickness (CIMT), and computed tomography angiography (CTA) are crucial for detecting atherosclerosis. These non-invasive methods help visualize plaque burden and vascular calcification in CKD patients. Vascular calcification is common in CKD patients and can be assessed using imaging modalities like plain radiographs, echocardiography, or more advanced techniques like multi-slice computed tomography (MSCT) to quantify calcification levels.

Management and Therapeutic Strategies

Blood pressure and lipid management in CKD

Optimal control of blood pressure and lipid levels is essential for managing both CKD and atherosclerosis. Angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs) are first-line therapies for controlling hypertension in CKD, while statins are recommended for managing dyslipidemia. Antiplatelet agents, such as aspirin, and antithrombotic therapy are commonly used in CKD patients to reduce the risk of cardiovascular events. However, these therapies must be carefully managed to balance the benefits against the increased risk of bleeding in CKD [8].

Novel therapies targeting inflammation and vascular health

Emerging therapies targeting inflammation and oxidative stress offer potential benefits in CKD and atherosclerosis management. Drugs such as pentoxifylline, anti-inflammatory biologics, and antioxidants are under investigation for their ability to modulate vascular health and slow disease progression. Treating vascular calcification in CKD is challenging due to the complex interplay between mineral metabolism and cardiovascular risk. Strategies include controlling serum phosphate levels, using phosphate binders, and new drugs like calcimimetics and vitamin D analogs to mitigate calcification.

Challenges in Treating CKD and Atherosclerosis

Therapeutic limitations and patient compliance

Patient compliance with treatment regimens is often poor, due to the complexity of managing multiple medications and lifestyle changes. Polypharmacy increases the risk of drug interactions and adverse effects, complicating long-term care. CKD patients often require multiple medications, which increases the potential for drug interactions, particularly between cardiovascular and renal treatments. Careful monitoring and dose adjustments are necessary to avoid renal toxicity and optimize treatment efficacy. Balancing the management of CKD and cardiovascular health is challenging, as therapies for one condition may negatively impact the other. For example, some antihypertensives or diuretics used to control blood pressure may worsen kidney function.

Future directions and research

New therapeutic targets, including anti-inflammatory agents, lipid-modifying drugs, and therapies aimed at reducing oxidative stress, are being explored to improve outcomes in patients with CKD and atherosclerosis. Research in these areas may provide breakthroughs in preventing disease progression. Personalized medicine approaches, such as genetic testing and biomarker profiling, have the potential to revolutionize CKD and atherosclerosis management by allowing for more tailored and effective treatment plans. A multidisciplinary care model involving nephrologists, cardiologists, dietitians, and other healthcare providers is essential to address the complex needs of patients with coexisting CKD and atherosclerosis. Collaborative care ensures comprehensive risk management and improved patient outcomes.

Result and Discussion

Prevalence and association between CKD and atherosclerosis

Multiple studies indicate a strong correlation between CKD and atherosclerosis. In CKD patients, the prevalence of atherosclerosis is significantly higher compared to the general population, with coronary artery disease (CAD) and cerebrovascular disease being the most common cardiovascular manifestations. Analysis of large cohorts, such as the Chronic Renal Insufficiency Cohort (CRIC), has revealed that 60-70% of CKD patients exhibit evidence of subclinical atherosclerosis, even in early stages of kidney disease. Imaging results using coronary artery calcium (CAC) scoring demonstrate that CKD patients have increased vascular calcification compared to non-CKD individuals, even after adjusting for traditional cardiovascular risk factors.

Endothelial dysfunction and vascular calcification in CKD

Results from biochemical assessments indicate that CKD patients exhibit higher levels of endothelial dysfunction markers such as asymmetric dimethylarginine (ADMA) and vascular cell adhesion molecule-1 (VCAM-1), which correlate with increased plaque burden. Moreover, the severity of vascular calcification is directly proportional to declining kidney function, with stage 4-5 CKD patients showing the highest calcification scores.

Impact of therapeutic interventions

In terms of management, data shows that aggressive control of blood pressure and lipid levels through the use of ACE inhibitors/ARBs and statins leads to a reduction in cardiovascular events in CKD patients. However, therapies targeting vascular calcification have had mixed results. Use of phosphate binders and calcimimetics has shown modest improvements in controlling serum phosphate levels, but their effects on halting calcification are less pronounced. Moreover, novel anti-inflammatory therapies, though promising in early-phase trials, require larger studies for validation.

Discussion

Prevalence and the bidirectional relationship

The findings confirm that CKD and atherosclerosis frequently coexist, with each condition exacerbating the other. The higher prevalence of atherosclerosis in CKD patients underscores the need for early cardiovascular risk assessment, even in early stages of CKD. The bidirectional nature of the relationship, where CKD accelerates vascular disease and atherosclerosis impairs renal perfusion, highlights the complexity of managing these patients. This interplay likely explains the high mortality rates observed in CKD patients, with cardiovascular disease accounting for the majority of deaths.

Pathophysiological mechanisms and disease progression

The elevated levels of endothelial dysfunction and vascular calcification markers in CKD patients are consistent with the known pathophysiology of atherosclerosis. Uremic toxins, oxidative stress, and altered calcium-phosphate metabolism appear to drive vascular damage in CKD. Vascular calcification, in particular, is a hallmark of CKD-related atherosclerosis and may represent a therapeutic target, though current treatment options are limited in efficacy. These findings further emphasize the need for a better understanding of the molecular mechanisms involved in calcification and plaque formation in CKD patients.

Efficacy of current management strategies

The results indicate that traditional cardiovascular risk factor modification, particularly blood pressure and lipid management, remains the cornerstone of treatment for CKD patients with atherosclerosis. The use of statins and renin-angiotensin-aldosterone system (RAAS) inhibitors has been shown to reduce cardiovascular events, yet questions remain regarding their long-term renal benefits, especially in advanced CKD. Moreover, while phosphate binders and calcimimetics help manage serum phosphate levels, their ability to mitigate vascular calcification remains uncertain.

Challenges in treating vascular calcification

One of the most significant challenges highlighted by the results is the management of vascular calcification in CKD. Current therapeutic options have limited success in reversing or preventing calcification, indicating a gap in treatment strategies. Future therapies may need to target the mineral metabolism pathways more effectively or address the inflammatory processes driving calcification in CKD. There is also a need for better diagnostic tools to identify and monitor vascular calcification progression more accurately in CKD patients.

Patient compliance and therapeutic challenges

Therapeutic compliance remains a critical issue in managing CKD and atherosclerosis, particularly given the complexity of treatment regimens. Polypharmacy is common, increasing the risk of drug interactions and side effects, which can reduce adherence to prescribed therapies. Patient education and the use of interdisciplinary care teams may help improve compliance, but more work is needed to simplify treatment regimens and reduce the burden of medication management on patients.

Future directions and research

The findings suggest several areas for future research, including the development of novel therapies targeting the molecular drivers of atherosclerosis and vascular calcification in CKD. Anti-inflammatory agents, new lipid-lowering therapies, and personalized medicine approaches may offer significant advancements. Additionally, more robust clinical trials are necessary to confirm the efficacy of emerging therapies and to refine existing treatment guidelines. Finally, interdisciplinary collaboration between nephrologists, cardiologists, and researchers will be essential to improving the long-term outcomes for CKD patients at risk of atherosclerosis.

Conclusion

The interplay between chronic kidney disease (CKD) and atherosclerosis significantly worsens patient outcomes, with cardiovascular disease being the leading cause of mortality in CKD patients. Shared risk factors, endothelial dysfunction, oxidative stress, and vascular calcification drive this complex relationship. While traditional management strategies like blood pressure and lipid control offer benefits, challenges remain in addressing vascular calcification and improving therapeutic compliance. Future research and interdisciplinary care are crucial for developing more effective treatments and improving long-term outcomes for patients with coexisting CKD and atherosclerosis.

Acknowledgment

None

Conflict of Interest

None

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