[Birth cohort effect on prevalence of cardiovascular risk factors in coronary artery disease. Experience in a Latin-american country].

Background: The prevalence of major risk factors associated to coronary artery disease has changed over time. Today, the frequency of dyslipidemia, hypertension and diabetes mellitus has increased, while smoking has decreased. The birth cohort effect for coronary artery disease in subjects as an approximation of the true prevalence over time has not been studied in Latin-America.

Objective: To determine the trends in the prevalence of major risk factors for coronary artery disease by birth cohort effect in a high risk population.

Methods: We estimate the prevalence of diabetes mellitus, smoking, hypertension and dyslipidemia from a prospective institutional registry (DREST registry) of patients who underwent percutaneous coronary intervention for acute coronary event. Birth cohort effect was defined as a statistical, epidemiological and sociological methodology to identify the influence of the environment in the lifetime from birth by each decade. Univariate and multivariate analyses were performed adjusted by gender.

Results: Out of 3,056 subjects who were enrolled, 72% were male, with a median age of 61 years (interquartile range=53-69). Hypertension prevalence was 62.3%, for diabetes mellitus it was 48.8%, for smoking it was 18.8% and for dyslipidemia it was 48.8%. We observed an increase in prevalence for diabetes mellitus and dyslipidemia in each cohort according to birth decade, while there was a reduction in prevalence for hypertension in the same decades.

Conclusions: The prevalence of major cardiovascular risk factors has changed in time and the presence of time at birth effect is evident, possibly influenced by the environment's social conditions in each decade of life.