Abstract P398: Are the Trends in Age-Standardized Rates and Crude Numbers of Coronary Events Diverging? Results from the FINAMI Study for the Years 1993–2007
Authors: Salomaa Veikko , Havulinna Aki S , Koukkunen Heli , Kärjä-Koskenkari Päivi , Pietilä Arto , Immonen-Räihä Pirjo , Ketonen Matti , Lehtonen Aapo , Lehto Seppo , Airaksinen Juhani , Kesäniemi Y Antero ,   FINAMI Study Group
Published: July 2021

Background and Aims:
Age-standardized rates of acute coronary events have been declining in all western countries. Concerns have been raised, however, that the absolute numbers of cases may be increasing due to the aging of the population. We examined trends in acute coronary events using data from the FINAMI myocardial infarction (MI) register. We also analyzed trends in coronary and other cardiac events in the whole country, using both age-standardized rates and crude numbers of cases to elucidate the effect of aging of the population.

Methods:
FINAMI is a population-based MI register, which aims at registering all MI events occurring in the populations aged 35 or over in five geographical areas of Finland. Hospital records, death certificates and other relevant documents were scrutinized and cases were classified to diagnostic categories as recommended by the AHA in 2003. To obtain information on the whole country we used record linkage of the National Hospital Discharge Register and Causes of Death Register. International Classification of Diseases (ICD-10) codes I20-I25 were taken as coronary events, for fatal cases we also included I46, R96 and R98. Other cardiac events consisted of ICD-10 codes I30-I52, thus including heart failure and arrhythmias. Annual population counts for the denominators were obtained from the National Population Information System. Event rates were age-standardized to the European Standard Population. Trends for the rates were estimated using Poisson regression and for crude numbers using linear regression.

Results:
The FINAMI MI register recorded 15,776 (13,248 men and 11,657 women) incident (=first) coronary events during the study period. In whole country, the corresponding numbers of first coronary events were 406,222 (221,838 in men and 184,383 in women). In FINAMI areas, the coronary mortality declined an average by 4.5% per year in men (P<0.0001) and 4.7% per year in women (p<0.0001). Declines in the incidence were smaller but also very significant: 1.6% and 1.8% per year in men and women, respectively (p<0.0001 for both). In country-wide data, declines in the age-standardized incidence were of the same order of magnitude as in the FINAMI areas and the crude numbers of cases also showed a declining trend: 0.4% per year in men (p=0.046) and 1.5% per year in women (p<0.0001). The age-standardized incidence of other cardiac events showed significant declines in both sexes, but the crude numbers of cases showed a modest increasing trend among men (1.1% per year, p=0.038) while no change was observed in women.

Conclusions:
Age-standardized incidence and mortality of coronary events continue to decline in Finland. The crude numbers of coronary events have also declined at least until 2007, despite the aging of the population. However, crude numbers of other first cardiac events, including heart failure and arrhythmias, showed a modest increasing trend among men.