Journal of Atherosclerosis and Thrombosis
Online ISSN : 1880-3873
Print ISSN : 1340-3478
ISSN-L : 1340-3478
Review
Atherosclerotic Diseases in Chronic Kidney Disease
Toshiaki Nakano
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2025 Volume 32 Issue 2 Pages 111-119

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Abstract

Patients with chronic kidney disease (CKD) have a high incidence of atherosclerotic diseases, such as ischemic heart disease, cerebrovascular disease, and peripheral arterial disease. To prevent the incidence of atherosclerotic cardiovascular disease in patients with CKD, the pathology of arteriosclerosis should be determined. Vascular calcification is a characteristic of arteriosclerosis in patients with CKD. Recent studies have reported that coronary artery calcification is associated with acute coronary syndromes. CKD is frequently associated with heart failure. Furthermore, recent evidence suggests that coronary artery calcification affects asymptomatic myocardial ischemia. Hyperphosphatemia and calciprotein particles may be involved in the pathology of vascular calcification. Controlling the progression of vascular calcification and classical atherosclerotic risk factors is important to prevent the occurrence of atherosclerotic diseases in CKD.

I. Introduction

The number of patients with chronic kidney disease (CKD) has been increasing along with an increase in lifestyle-related diseases and the population1, 2). Patients with CKD appear to have a higher incidence of cardiovascular complications than a population with a normal kidney function. Therefore, lipid-lowering therapies such as statins have been considered to prevent the development of atherosclerotic cardiovascular disease (ASCVD)3). The fact that the effect of lipid-lowering therapy using statins in reducing atherosclerotic cardiovascular events diminishes as CKD progresses to end-stage renal failure suggests that the pathology of atherosclerosis in patients with CKD may be altered4, 5).

In recent years, evidence has suggested that vascular calcification affects plaque rupture and calcified nodules and exacerbates the development of acute coronary syndrome6). In addition, coronary artery calcification may cause microcirculatory disturbances in the heart7). This review summarizes the epidemiological and pathological characteristics of ASCVD associated with CKD.

II. Epidemiology of Cardiovascular disease in patients with CKD

In a large cohort study, the incidence of cardiovascular disease was 36.6 times higher in a population with a low estimated glomerular filtration rate (eGFR) of 15 ml/min/1.73 m2 than in a population with a normal kidney function8). In addition, the incidence of cardiovascular disease was 3.4 times higher after multivariate adjusting for risk factors than that in a population with a normal kidney function. A cohort study of the general Japanese population similarly reported that CKD is an independent risk factor for the development of cardiovascular disease9). Several other reports have shown that CKD and proteinuria are independent risk factors for the development of cardiovascular disease and death10-12).

Common risk factors for CKD and cardiovascular diseases, such as hypertension, diabetes, and dyslipidemia, increase the risk of cardiovascular complications in CKD patients (Fig.1). In the Suita Study, a multivariate adjusted analysis (adjusted for age, sex, smoking, diabetes, hypertension, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol) showed that the incidence of coronary artery disease was 1.34 times higher in CKD stage 3 and 4.01 times higher in CKD stages 4 and 5 than in the general population13). Therefore, the risk of developing coronary artery disease due to CKD remains even after multivariate adjusting for the classical risk factors for atherosclerosis. This finding may be explained by the fact that CKD has various risk factors for cardiovascular disease, such as abnormal calcium and phosphorus metabolism, anemia, accumulation of urea toxins, oxidative stress, chronic inflammation, endothelial dysfunction, increased renin–angiotensin system (RAS) activity, and an increased sympathetic nerve function14-16) (Table 1, Fig.1).

Fig.1. Interaction between CKD and ASCVD

Classical risk factors for ASCVD include the progression of atherosclerosis, CKD, heart disease, and stroke. CKD-specific risk factors also affect the progression of atherosclerosis, heart disease, and strokes. CKD, chronic kidney disease; ASCVD, atherosclerotic cardiovascular disease; CKD-MBD, chronic kidney disease-mineral bone disorder.

Table 1.Risk factors for atherosclerosis in patients with CKD

Classical risk factor Specific risk factor in CKD
Age Mineral bone metabolism
Male gender Vascular calcification
Hypertension Uremic toxin
Diabetes mellitus Renal anemia
Dyslipidemia Oxidative stress
Obesity Chronic Inflammation
Smoking Abnormal lipid modifications
Endothelial dysfunction
Renin angiotensin activity
Sympathetic nerve activity

Patients on dialysis have a higher incidence of ASCVD than the general population17). Lipid-lowering therapy with statins has been used for patients with CKD. In a clinical trial, a post hoc analysis of pre-dialysis CKD patients showed that statins were effective3). However, statins alone failed to prevent cardiovascular events in patients undergoing dialysis4, 5). Therefore, risk factors for atherosclerotic diseases other than dyslipidemia may be involved in patients undergoing dialysis.

III. Frequency of Coronary Artery Disease and Coronary Artery Calcification in Patients with CKD

Ischemic heart disease is a relatively frequent complication in CKD patients. According to the Japanese Society for Dialysis Therapy, myocardial infarction accounted for 3.3% of the causes of death among patients on dialysis in Japan in 2022, which was lower than that in previous years18). Deaths directly caused by myocardial infarction have been decreasing owing to the increased use of RAS system inhibitors and statins, therapeutic interventions for renal anemia, and early screening for cardiac diseases. However, regarding a history of ischemic heart disease in predialysis patients with CKD, recent reports from Japan showed a prevalence of 13.4% in the CKD-JAC Study and 10.8% in the Fukuoka Kidney disease Registry Study19, 20). This finding indicates that ischemic heart disease is a frequent complication of chronic kidney disease. A study of myocardial scintigraphy to screen for ischemic heart disease before the induction of dialysis was performed in Japan21). This study reported that 22% of the patients with end-stage renal failure had ischemic heart disease, and the frequency of complications remained high. An autopsy study showed that advanced atherosclerotic lesions in the coronary arteries increased with CKD stage progression22) (Fig.2). Therefore, the prevention of ischemic heart disease remains an important issue in patients with CKD.

Fig.2. Proportions of atherosclerotic lesions in accordance with the AHA classification associated with the kidney function

The bar graphs indicate the percentage of atherosclerotic lesions estimated based on the AHA classifications according to different eGFRs. The percentages of advanced atherosclerosis (AHA types IV–VI) for the respective eGFRs are shown on the right side of the graphs. The figure was reproduced from an article by Nakano et al.22) with permission from the publisher.

A study that evaluated coronary artery calcification in patients with CKD who underwent chest computed tomography reported that a higher degree of vascular calcification in the coronary arteries was associated with a poorer survival rate23). Vascular calcification can occur in the intima and the tunica media. Calcification in the tunica media is called Mönckeberg medial calcific sclerosis and is characteristic of patients with CKD and diabetes, often being found in muscular arteries of the upper and lower extremities and pelvic arteries24). However, calcification in the intima often occurs with atherosclerosis and has been reported to be associated with a poorer prognosis than medial calcification25). Although the frequency of medial and intimal calcification in the coronary arteries of patients with CKD is unclear, calcification in the intima of coronary arteries is reported to occur with atherosclerosis in patients with CKD22, 26). The frequency of vascular calcification in the coronary arteries was reported in autopsy cases in the Hisayama Study2, 22). In the present study, patients with CKD and an eGFR <30 mL/min/1.73 m2 had a 4.7-fold increased risk of coronary artery calcification compared with the general population with an eGFR ≥ 60 mL/min/1.73 m2 22). Therefore, patients with CKD have an increased frequency of coronary artery calcification, which may be associated with coronary artery disease.

IV. Pathogenesis of Acute Coronary Syndrome with Coronary Calcification

Acute coronary syndrome is mainly caused by plaque rupture, plaque erosion, and calcified nodules. The most common cause of acute coronary syndrome is plaque rupture, in which rupture of the atheroma results in thrombus formation in the coronary artery. Plaque erosion, in which a thrombus forms on the intimal surface of the plaque, occludes the coronary artery27). Risk factors for plaque rupture include a large lipid core, thin fibrous capsule, high inflammatory cell infiltrates, high levels of angiogenesis, enlarged necrotic core, and positive remodeling28). Recently, coronary calcification was reported to be associated with plaque rupture29). It is difficult to determine whether or not calcification in the intima of coronary arteries directly affects plaque rupture. However, in a previous study, optical coherence tomography during coronary angiography to evaluate the responsible lesion showed that coronary arteries with plaque rupture had spotty calcification in the intima30). This finding suggests that microcalcifications and fragmented calcifications in the intima may be risk factors for plaque ruptures.

Thin-cap fibroatheroma and ruptured plaques with a thin fibrous capsule, which are at high risk of rupture, are often associated with microcalcifications (between 0.5 and 15 µm) and fragmented calcifications (<3 mm) in the intima27, 29). Sheet calcification (>3 mm) is frequently observed in healed plaque ruptures and fibrocalcific plaques and may be associated with stable plaques with a low risk of rupture27, 29). An autopsy study showed that vascular calcification was associated with intraplaque hemorrhage, which is a risk factor for plaque destabilization31) (Fig.3). Macrophage infiltration is also associated with the risk of intraplaque hemorrhage and vascular calcification31). These findings suggest that vascular calcification increases the frequency of ASCVD events in patients with advanced atherosclerotic lesions.

Fig.3. Representative images of coronary arteries with calcification and the frequency of intraplaque hemorrhage

(A) Coronary artery with calcification and massive hemorrhage (indicated by an asterisk). The calcification area is 0.83 mm2. (B) Coronary artery with moderate calcification and moderate hemorrhage (asterisk). The calcification area is 1.68 mm2. (C) Coronary artery with moderate calcification, necrosis, and a small amount of hemorrhage (asterisk). The calcification area is 3.24 mm2. (D) Coronary artery with a large calcification area. There is no intraplaque hemorrhage. The calcification area is 5.56 mm2. Arrowheads in the images show the calcification area (A–D). Scale bars indicate 1.0 mm (A–D). (E) The multivariable-adjusted model was adjusted for age, sex, estimated glomerular filtration rate, systolic blood pressure, diabetes, serum total cholesterol concentrations, serum high-density lipoprotein cholesterol concentrations, calcium concentrations, phosphate concentrations, hemoglobin concentrations, current smoking, and current drinking. The solid line represents the adjusted odds ratio, and the dotted line represents the 95% CI. The calcification area at the highest odds ratio for intraplaque hemorrhage was 1.98 mm2. The images were reproduced from an article by Nakano et al.31). CI, confidence interval.

Recently, calcified nodules protruding into the lumen of coronary arteries have been shown to cause thrombosis6). Necrotic cores in fibroatheroma may become extensively calcified (sheet calcification) over time, forming fibrocalcific plaques. Mechanical stress on diffuse calcified arteries is thought to destroy plate calcification, forming calcified nodules by aggregation of a necrotic core and calcification (Fig.4). Calcified nodules are often observed in patients with CKD, and balloon intervention often does not provide sufficient dilation for stenotic lesions around calcified nodules in the coronary arteries. Even when stenotic lesions are dilated, calcified nodules may reappear in the stent, causing thrombosis and restenosis.

Fig.4. Atherosclerotic lesions with calcification in CKD

(A) CPPs in vessels induce an inflammatory response in macrophages, endothelial cells, and smooth muscle cells. Blue stars indicate CPPs. (B) Calcification in the intima is often associated with intraplaque hemorrhage. (C) A calcified nodule protrudes into the lumen, disrupting the fibrous cap, and is associated with thrombus formation. CPPs, calciprotein particles.

Therefore, calcification in coronary arteries is a risk factor for plaque rupture, and the formation of calcified nodules can lead to thrombus formation in the lumen, resulting in acute coronary syndrome.

V. Heart Failure Associated with CKD

CKD is frequently associated with left ventricular hypertrophy, especially afferent left ventricular hypertrophy32, 33). This condition may be due to the fact that hypertension is more frequently complicated by impaired sodium excretion with a decreased kidney function than a normal kidney function, resulting in an increased frequency of left ventricular hypertrophy. In a recent autopsy study, left ventricular wall thickening increased as CKD progressed, and considerable left ventricular wall thickening was observed even after adjusting for risk factors such as hypertension and diabetes mellitus34). Furthermore, an evaluation of myocardial fibrosis showed expansion of fibrosis in myocardial tissue with the progression of the CKD stage. Myocardial wall thickening was also shown to be accompanied by swelling of myocytes, suggesting that local RAS is activated in myocytes35). Myocardial fibrosis may also indicate the presence of peripheral circulatory disturbances within the myocardium. CKD pathogenesis is accompanied by abnormal calcium and phosphorus metabolism, which is associated with an increased frequency of calcification in the vascular intima and medial lesions. Such calcification of the vessel wall contributes to increased arterial stiffness and left ventricular hypertrophy36). In addition, peripheral myocardial tissue has a high risk of ischemia owing to increased vascular stiffness with calcification, leading to fibrosis and an increased risk of heart failure. Therefore, CKD may predispose patients to left ventricular hypertrophy and myocardial fibrosis.

VI. Coronary Microcirculatory Dysfunction and Coronary Artery Calcification

In recent years, there has been widespread implementation of emergency coronary angiography for acute coronary syndrome, with the development of diagnostic techniques using highly sensitive troponin. This has led to the proposal of a new concept of myocardial infarction without nonobstructive coronary arteries (MINOCA) and ischemia with nonobstructive coronary artery disease (INOCA)37). MINOCA occurs not only in patients with heart failure or atrial fibrillation but also in patients with cerebrovascular disease, peripheral arterial disease, and CKD38). The main causes of INOCA are coronary spasms and microvascular dysfunction. Coronary microvascular dysfunction frequently occurs in the hearts of patients with CKD39).

One study evaluated asymptomatic myocardial ischemia in patients on hemodialysis without a history of ischemic heart disease using fatty acid metabolic scintigraphy40). Fatty acid metabolism is frequently impaired in the presence of myocardial ischemia in patients on hemodialysis, which suggests that asymptomatic myocardial ischemia (i.e. INOCA) is more common in the hearts of patients on dialysis than the general population. Furthermore, studies that measured coronary flow reserve (CFR) reported that CFR was lower in patients with CKD than in those without CKD39). Patients with CKD have an impaired vascular endothelial function, which may contribute to a reduced CFR. Another study reported an inverse correlation between the degree of coronary artery calcification and CFR7). These findings suggest that the frequency of coronary microvascular dysfunction is high in CKD patients. In addition, coronary microvascular dysfunction may be caused by impaired vasodilation due to impaired vascular endothelial function and increased vascular resistance due to vascular calcification. Therefore, vascular calcification may also affect myocardial circulatory disturbances.

VII. Cerebrovascular Complications Associated with CKD

Patients with CKD are at a higher risk of developing cerebrovascular disease than those without CKD. A meta-analysis of CKD and cerebrovascular disease reported a 7% increase in the risk of cerebrovascular disease for every 10 mL/min/1.73 m² decrease in the eGFR41). In addition, the appearance of microalbuminuria was reported to increase the risk of cerebrovascular disease 1.53-fold, while overt albuminuria was reported to increase the risk 1.94-fold41). A decline in the kidney function, albuminuria, and proteinuria in CKD are risk factors for cerebrovascular disease.

The risk of cerebrovascular disease is further increased in patients undergoing dialysis, with a 5.2-fold higher incidence than that in the general population17). Hypertension is the greatest risk factor; however, hyperphosphatemia, which is a characteristic of CKD, is associated with a 2.75-fold increased risk of cerebral hemorrhaging42). Renal anemia has also been reported as a risk factor for cerebrovascular disease43). These findings suggest that CKD pathophysiology contributes to the risk of cerebrovascular disease.

VIII. Treatment of Cardiovascular Disease in Patients on Dialysis

The DOPPS study showed that patients on dialysis have a high mortality rate44). Furthermore, patients on dialysis have a higher incidence of atherosclerotic disease than the general population17). Therefore, managing the risk of cardiovascular disease in patients undergoing dialysis is important. In a Q-cohort study of patients on hemodialysis in Japan, those with a systolic blood pressure ≥ 172 mmHg had a higher incidence rate of cardiovascular events than those with systolic blood pressure between 148 to 159 mmHg45). Regarding dyslipidemia, cardiovascular events were also increased in patients with total cholesterol concentrations ≥ 178 mg/dL46). Therefore, hypertension and dyslipidemia are risk factors for cardiovascular events in patients undergoing dialysis.

Notably, hyperphosphatemia is associated with cerebral hemorrhaging and peripheral arterial disease42, 47). Hyperphosphatemia may cause endothelial dysfunction, and calciprotein particles (CPPs) induced by hyperphosphatemia may induce inflammation in macrophages and vascular smooth muscle cells, leading to atherosclerosis48) (Fig.4). In addition, a recently published post hoc analysis of the AURORA study showed that rosuvastatin did not prevent major adverse cardiovascular events in patients on hemodialysis with serum phosphorus concentrations >5 mg/dL49). However, rosuvastatin reduced major adverse cardiovascular events in patients with serum phosphorus concentrations <5 mg/dL. Therefore, hyperphosphatemia may attenuate the effect of statins on the suppression of cardiovascular diseases in patients undergoing hemodialysis. In addition to interventions for classical risk factors, such as hypertension and dyslipidemia, the management of CKD-mineral and bone disorders is also important in treating cardiovascular disease in patients on hemodialysis.

IX. Conclusion

CKD is associated with several risk factors for atherosclerotic diseases, such as hypertension. CKD is also associated with cardiovascular disease owing to the presence of unique pathologies, such as vascular calcification, renal anemia, accumulation of uremic toxins, endothelial dysfunction, and enhancement of the local RAS. In recent years, evidence has suggested that vascular calcification in coronary arteries directly affects acute coronary syndrome or coronary microvascular dysfunction, which in turn may affect MINOCA and INOCA. Hyperphosphatemia has also been implicated in the development of cerebral hemorrhaging and peripheral arterial disease in patients undergoing hemodialysis. Prevention of atherosclerotic disease in patients with CKD requires management of mineral bone metabolism to prevent vascular calcification, in addition to management of classical risk factors, such as hypertension, diabetes, and dyslipidemia.

Acknowledgements

We thank Ellen Knapp, Ph.D., from Edanz (https://jp.edanz.com/ac) for editing the draft of this manuscript.

Conflict of Interest

The author declares no competing interests.

References
 

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