Urinary albumin-to-creatinine ratio levels are associated with subclinical atherosclerosis and predict CVD events and all-cause deaths: a prospective analysis

Abstract

Objective: We aimed to examine the associations of urinary albumin-to-creatinine ratio (ACR) levels with risks of subclinical atherosclerosis, cardiovascular events and all-cause deaths.

Methods: Data from a large population-based cohort were used, which included 9580 participants aged ≥40 years free from cardiovascular diseases. Carotid intima-media thickness, brachial-ankle pulse wave velocity and ankle-brachial index were measured at baseline to assess subclinical atherosclerosis. After a median of 4.53 years' follow-up, 486 cardiovascular events and 230 all-cause deaths were recorded.

Results: The urinary ACR levels were categorised into three groups. Compared with the normal group (0≤ACR <7.82 mg/g), people with low-grade albuminuria (7.82≤ACR <30 mg/g) and albuminuria (ACR ≥30 mg/g) had higher levels of subclinical atherosclerosis. In prospective analysis, people with low-grade albuminuria was not significantly associated with cardiovascular events (HR=1.18; 95% CI 0.95 to 1.46], whereas people with albuminuria had a 50% higher risk of cardiovascular events (HR=1.50; 95% CI 1.11 to 2.03). People with low-grade albuminuria and albuminuria had 43% (HR=1.43; 95% CI 1.05 to 1.93) and 87% (HR=1.87; 95% CI 1.24 to 2.81) higher risks of all-cause deaths during follow-up, respectively. In stratified analysis, the association of higher ACR with risks of cardiovascular events and all-cause deaths was stronger among individuals with concomitant subclinical atherosclerosis, the presence of diabetes and more cardiovascular risk factors, respectively.

Conclusions: ACR levels were positively associated with subclinical atherosclerosis and predicted the risks of cardiovascular events and all-cause deaths. Evaluation of ACR levels should be integrated into risk stratification and prevention of cardiovascular events and all-cause deaths, especially among those with pre-existing subclinical atherosclerosis and cardiometabolic abnormalities.

Keywords: cardiology; coronary heart disease; myocardial infarction.

Figure 1

Study flowchart. Subclinical atherosclerosis: (1) carotid atherosclerosis (carotid intima-media thickness >0.6 mm or the presence of carotid stenosis as 50%), (2) elevated Ba-PWV (Ba-PWV >1789 cm/s) or (3) abnormal ABI (ABI<0.9 or ABI>1.4). Cardiovascular events: the first instance of nonfatal myocardial infarction, nonfatal stroke, congestive heart failure or cardiovascular-related deaths. ABI, ankle-brachial index; ACR, albumin-to-creatinine ratio; Ba-PWV, brachial-anklepulse wave velocity.

Figure 2

(A–H). Risks of cardiovascular events and all-cause deaths according to different ACR groups stratified by baseline subclinical atherosclerosis. Carotid atherosclerosis (A, B), elevated Ba-PWV (C, D), abnormal ABI (E, F), presence of subclinical atherosclerosis (G, H). The model was adjusted for age, sex, body mass index, education level, current smoking, current drinking, physical activity, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, total cholesterol, systolic blood pressure, diabetes status, eGFR. ABI, ankle-brachial index; ACR, albumin-to-creatinine ratio; Ba-PWV, brachial-ankle pulse wave velocity; eFGR, estimated glomerular filtration rate; ref., reference.

Figure 3

(A–D). Risks of cardiovascular events and all-cause deaths according to different ACR groups stratified by diabetes status and number of cardiovascular risk factors. Diabetes status (A, B), number of cardiovascular risk factors (C, D). The model was adjusted for age, sex, education level, current drinking, eGFR. ACR, albumin-to-creatinine ratio; eGFR, estimated glomerular filtration rate; ref., reference.