Comparison of C-reactive protein and albumin excretion as prognostic markers for 10-year mortality after myocardial infarction

Abstract

Background: C-reactive protein (CRP) is an established prognostic marker in the setting of acute coronary syndromes. Recently, albumin excretion rate also has been found to be associated with adverse outcomes in this clinical setting. Our aim was to compare the prognostic power of CRP and albumin excretion rate for long-term mortality following acute myocardial infarction (AMI).

Hypothesis: To determine whether albumin excretion rate is a better predictor of long-term outcome than CRP in post-AMI patients.

Methods: We prospectively studied 220 unselected patients with definite AMI (median [interquartile] age 67 [60-74] y, female 26%, heart failure 39%). CRP and albumin-to-creatinine ratio (ACR) were measured on day 1, day 3, and day 7 after admission in 24-hour urine samples. Follow-up duration was 10 years for all patients.

Results: At survival analysis, both CRP and ACR were associated with increased risk of 10-year all-cause mortality, also after adjusting for age, hypertension, diabetes mellitus, prehospital time delay, creatine kinase-MB isoenzyme peak, heart failure, and creatinine clearance. CRP and ACR were associated with nonsudden cardiovascular (non-SCV) mortality but not with sudden death (SD) or noncardiovascular (non-CV) death. CRP was not associated with long-term mortality, while ACR was independently associated with outcome both in short- and long-term analyses. At C-statistic analysis, CRP did not improve the baseline prediction model for all-cause mortality, while it did for short-term non-SCV mortality. ACR improved all-cause and non-SCV mortality prediction, both in the short and long term.

Conclusions: ACR was a better predictor of long-term mortality after AMI than CRP.

Figure 1

Kaplan‐Meier estimates of the probability of all‐cause and non‐sudden cardiovascular mortality in the patients stratified by tertiles of C‐reactive protein (CRP) and albumin‐to‐creatinine ratio (ACR)