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. 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