Admission C-reactive protein and short- as well as long-term mortality in diabetic versus non-diabetic patients with incident myocardial infarction

Abstract

Background: To investigate the association between admission C-reactive protein (CRP) levels and 28-day case fatality as well as long-term mortality after an incident acute myocardial infarction (AMI) in non-diabetic and diabetic patients.

Methods: The study was based on 461 diabetic and 1,124 non-diabetic persons consecutively hospitalized with a first-ever MI between January 1998 and December 2003 recruited from a population-based MI registry. The study population was stratified into two groups of admission CRP concentrations (cut-off point median </≥0.5 mg/dl).

Results: The patients were followed up until 31st December 2005 (median follow-up time of 4.0 years). After multivariable adjustment the odds ratio (OR) (95% confidence interval) for 28-day case fatality among those with high admission CRP values in comparison to persons with low CRP values were 2.55 (1.52-4.28) for the overall population, 2.53 (1.29-4.96) for non-diabetic patients, and 2.75 (1.18-6.37) for diabetic patients. Admission CRP concentration was also associated with long-term mortality. After multivariable adjustment persons with high admission CRP values had a relative risk of 1.90 (95% CI 1.36-2.65) for all-cause mortality compared with those who had CRP values below the median; the corresponding HR in non-diabetic persons was 2.15 (95% CI 1.38-3.35) and in diabetic persons it was 1.38 (95% CI 0.83-2.30).

Conclusions: Admission CRP is a strong risk marker of bad short-term prognosis after an incident AMI. However, in contrast to non-diabetic patients in diabetic patients, admission CRP is not independently associated with long-term prognosis.