Trends in 28-day and 1-year mortality rates in patients hospitalized for a first acute myocardial infarction in Norway during 2001-2009: a "Cardiovascular disease in Norway" (CVDNOR) project.

Abstract

OBJECTIVE: The aim of this study was to investigate the trends in 28-day and 1-year mortality rates in patients hospitalized for a first acute myocardial infarction (AMI) in Norway during the period 2001-2009. Potential age group and gender differences in these trends were also examined. DESIGN, SUBJECTS AND SETTING: In this retrospective nationwide cohort study, patients hospitalized for a first AMI between 2001 and 2009 were identified in the Cardiovascular Disease in Norway 1994-2009 (CVDNOR) project and followed for 1 year. MAIN OUTCOME MEASURES: Trends in 28-day and 1-year mortality [both all-cause and cardiovascular disease (CVD) mortality] were investigated. RESULTS: A total of 115,608 patients (60.6% men) were hospitalized for a first AMI during the study period. Mortality at 28 days was reduced annually by 3.8% overall and by 6.7%, 4.1% and 2.6% in patients aged 25-64, 65-84 and ≥85 years, respectively (all Ptrend < 0.001). In addition, 1-year all-cause mortality was reduced annually by 2.0% overall (Ptrend < 0.001) and by 3.7% (Ptrend = 0.02), 2.5% (Ptrend < 0.001) and 1.1% (Ptrend < 0.001) in patients aged 25-64, 65-84 and ≥85 years, respectively. Furthermore, 1-year CVD mortality was reduced overall by 6.2% annually; a reduction was observed in all age groups. Finally, 1-year non-CVD mortality increased annually overall by 3.9% due to an increase in patients aged ≥65 years. CONCLUSION: Mortaity at 28 days after the first AMI declinedin Norway between 2001 and 2009 in both men and women and in all age groups. All-cause mortality at 1 year also declined both in men and women due to decreases in CVD mortality rates, whilst non-CVD mortality rates increased amongst patients ≥65 years of age.