Ecological study of reasons for sharp decline in mortality from ischaemic heart disease in Poland since 1991

Abstract

<b>Objective:</b> To investigate the reasons for the decline in deaths attributed to ischaemic heart disease in Poland since 1991 after two decades of rising rates. <b>Design:</b> Recent changes in mortality were measured as percentage deviations in 1994 from rates predicted by extrapolation of sex and age specific death rates for 1980-91 for diseases of the circulatory system and selected other categories. Available data on national and household food availability, alcohol consumption, cigarette smoking, socioeconomic indices, and medical services over time were reviewed. <b>Main outcome measures:</b> Age specific and age standardised rates of death attributed to ischaemic heart disease and related causes. <b>Results:</b> The change in trend in mortality attributed to diseases of the circulatory system was similar in men and women and most marked (&gt;20%) in early middle age. For ages 45 to 64 the decrease was greatest for deaths attributed to ischaemic heart disease and atherosclerosis (around 25%) and less for stroke (&lt;10%). For most of the potentially explanatory variables considered, there were no corresponding changes in trend. However, between 1986-90 and 1994 there was a marked switch from animal fats (estimated availability down 23%) to vegetable fats (up 48%) and increased imports of fruit. <b>Conclusion:</b> Reporting biases are unlikely to have exaggerated the true fall in ischaemic heart disease; neither is it likely to be mainly due to changes in smoking, drinking, stress, or medical care. Changes in type of dietary fat and increased supplies of fresh fruit and vegetables seem to be the best candidates. <h3>Key messages</h3> Among former socialist countries Poland has undergone unusually rapid social and economic changes since 1988-9, including aspects of diet Mortality from heart disease declined sharply during 1991-4 after long term increases; mortality from stroke declined less strongly This study investigated what has changed in Poland to reduce the risks of fatal events in people with established ischaemic heart disease Candidate dietary explanations were the substitution of unsaturated for saturated fats and increased consumption of fresh fruit and vegetables