[Age-period-cohort analysis of mortality caused by ischemic cardiopathy in Spain 1965-1985].

With the objective of studying the temporal evolution of ischaemic cardiopathy (IC), or coronary heart disease mortality, in Spain, we carried out a cohort analysis with conventional graphic techniques and modern statistical methods. This permits better understanding and quantification of the age-period-cohort effects and identification of the potential factors operating upon them. To this end, loglineal (Poisson regression) models were constructed of the IC mortality rates for both sexes, using the GLIM package, in which the regression coefficients are the natural Relative Risk (RR) logarithms of the various age groups (35-74 years), period of death (1970-1985) and birth cohort (1985-1960) with respect to the reference group mortality, controlled by the effect of other groups. In respect of the results, the maximum RR value corresponds to decrease year 1975, and falls progressively to 1985, though at all times remaining above the 1970 value. The effect of 1985, though less than 1980, does not present significant differences from the latter. Nevertheless, no clear cohort effect was found. As a probable explanation for the pattern observed, this would suggest recent changes in life style and in medical attention. There is a discussion of the consistency of the models selected with the graphical results and with present knowledge of the natural history of IC and with the evolution of its determining factors, together with validation of the models. In summary, the IC mortality patterns observed show an increase up to the mid-seventies, and stabilization from that date onwards, in all age and sex groups, which is consistent with an age-period effect.