Hypothesis: the recent decline in coronary heart disease mortality--mainly a shift from fatal to non-fatal events?
OBJECTIVE
A marked, sequential decline in coronary heart disease (CHD) mortality is established, but not its causes. Does it reflect modern treatment effects or a spinoff of primary prevention? The aim of this study was to explore this issue using a prospective cohort follow-up design.


METHODS
In 1972-1975 and 1980-1982 Cohorts 1 (n = 613) and 2 (n = 667) of identical age (males, mean 56 years) were examined, and thereafter followed closely for 14 years. CHD risk- and treatment patterns, incidence of non-fatal myocardial infarctions (MIs) and total-, cardiovascular and CHD mortality rates were studied.


RESULTS
CHD risk factors were more favourable, medical treatment more aggressive and 14-years CHD mortality, as expected, lower in Cohort 2 (7.7%/4.8%, p = 0.032). However, hospital- and prospective ECG data revealed opposite trends in non-fatal cohort CHD incidence, and aggregated numbers of CHD deaths and non-fatal MI cases were 16.7%/16.0% in Cohort 1/2 (p = 0.90).


CONCLUSIONS
A marked, sequential reduction in CHD mortality was followed by a reciprocal increase in non-fatal MIs. This phenomenon may prevail in low CHD-endemic areas, and may call for altered primary preventive measures for reduction in total CHD incidence.
Erikssen
G
G
Medical Department, Central Hospital of Akershus, Nordbyhagen, Norway. k-eriks@online.no
Liestøl
K
K
Bjørnholt
J V
JV
Thaulow
E
E
Erikssen
J
J
D000368:Aged; D003327:Coronary Disease / Q000453:epidemiology / Q000401:mortality* / Q000517:prevention & control / Q000628:therapy; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009017:Morbidity; D009664:Norway / Q000453:epidemiology; D016016:Proportional Hazards Models; D011446:Prospective Studies; D016019:Survival Analysis