Observational multicenter study to evaluate the prevalence and prognosis of subclinical atheromatosis in a Spanish chronic kidney disease cohort: baseline data from the NEFRONA study

Abstract

BackgroundCardiovascular events (CVE) are more prevalent in chronic kidney disease (CKD) than in general population, being the main cause of morbimortality. Specific risk factors related to CKD have been suggested, because traditional factors do not fully explain this increase in cardiovascular disease rates. However, the role of atheromatosis, its pathogenesis and evolution are still unclear. The potential use of diagnostic tests to detect subclinical atheromatosis has to be determined.MethodsNEFRONA is a prospective multicenter cohort study. 2445 CKD subjects were enrolled from 81 Spanish hospitals and dialysis clinics, from 2010 to 2012. Eligibility criteria included: 18 to 74 years old, CKD stage 3 or higher, and no previous CVE. 559 non-CKD controls were also recruited. Demographical, clinical and analytical data were collected. Carotid and femoral ultrasounds were performed by a single trained team to measure carotid intima-media thickness (cIMT) and detect atheromatous plaques. Ankle-brachial index (ABI) was measured.ResultsDifferences in age, sex and prevalence and control of cardiovascular risk factors were found between controls and CKD patients. These differences are similar to those described in epidemiological studies.No difference was found regarding cIMT between controls and CKD (when subjects with plaques in common carotid arteries were omitted); earlier CKD stages had higher values. CKD patients had a higher rate of atheromatous plaques, with no difference between stages in the unadjusted analysis. A group of patients had plaques in femoral arteries but were plaque-free in carotid arteries, and would have gone underdiagnosed without the femoral study. The percentage of pathologic ABI was higher in CKD, with higher prevalence in more advanced stages, and a higher rate of ABI >1.4 than <0.9, suggesting more vascular calcification.ConclusionsNEFRONA is the first large study describing the actual prevalence of subclinical atheromatosis across different CKD stages. There is a very high rate of atheromatous plaques and pathologic ABI in CKD. Prospective data will add important information to the pathogenesis and evolution of atheromatosis in CKD, compared to non-CKD subjects.

The Relationship between Carotid and Femoral Artery Intima-Media Thickness and Histopathologic Grade of Atherosclerosis in Patients with Chronic Kidney Disease

“…Likewise, in our study, the median cIMT and fIMT values linearly increased in relation to the grade of atherosclerosis in the CKD patient population. These findings correlate with the established knowledge that atherosclerosis is a generalized disease involving several segments of the arterial system [14, 15, 41, 42]. …”

“…This somewhat contradicts established and previously published results that have reported a correlation between cIMT and degree of atherosclerosis in CABG patients. One possible explanation for this discrepancy would be the fact that prior published data demonstrated a correlation between IMT values and the number and severity of stenoses in the affected coronary arteries, not the histopathologic grade of atherosclerosis in a different set of arteries (in our case the aorta, renal, brachial, and radial arteries) [14, 15, 41, 42]. Another potential explanation would be that cIMT and fIMT values may only correlate with the grade of atherosclerosis in its early or developing stages, while patients with CABG almost always present with advanced atherosclerotic disease.…”

Predictors of Subclinical Atheromatosis Progression over 2 Years in Patients with Different Stages of CKD

“…Recently, baseline data from the National Observatory of Atherosclerosis in Nephrology (NEFRONA) (16) Study have shown that patients in early CKD stages already have a higher prevalence of atheromatous plaques than those without CKD (17,18), and as previously shown, this prevalence is even higher in advanced stages of CKD (19)(20)(21). However, it is uncertain what the velocity of atheromatosis progression in CKD is (22,23), and little is known about the predictors of plaque progression in patients with CKD.…”

“…A physical examination was performed, consisting of anthropometric measures, standard vital tests, and ABI measurements as previously described (16). A pathologic ABI was described as #0.9 or $1.4.…”

The Modality of Dialysis Does Not Influence Atheromatous Vascular Disease Progression or Cardiovascular Outcomes in Dialysis Patients Without Previous Cardiovascular Disease

“…A physical examination was performed, including in anthropometric measures, standard vital tests and ABI measurement as previously described [16]. A pathological ABI was described as 0.9 or !1.4.…”