Pathobiological determinants of atherosclerosis in youth (PBDAY Study), 1986-96.

This article is a summary of the 10-year multinational collaborative WHO/ISFC Study of Pathobiological Determinants of Atherosclerosis in Youth (PBDAY Study). Details are provided of the study design, relevant results, conclusions, and recommendations, as formulated at a consultation of the heads of PBDAY Reference Centres, held in Budapest, Hungary, in October 1996. The WHO/ISFC study provides unique information about the determinants of atherosclerosis and structural changes in the arteries, especially during their early stages, and their progression from early life in populations with vastly different lifestyles. The pilot study covered subjects aged 5-34 years, of both sexes, from 18 centres in 15 countries, while the main study covered 11 centres in 11 countries. Included were both developed and developing countries with different economic, sociocultural and nutritional patterns from five WHO regions. Collected was background epidemiological information, information about cases, and special studies of arteries using various morphometric methods and specialized techniques. Atherosclerotic lesions start to develop early in life independently of race, sex or geographical origin. The rate of fatty streak development is higher between 15 and 25 years of age, while raised lesions begin developing slowly during the second decade of life, progressing steadily during the third and more rapidly during the fourth. Fatty streaks are more prevalent among females and raised lesions among males. The prevalence and extent of raised lesions were greater in countries with a high prevalence of known risk factors and high mortality rates for cardiovascular diseases, coronary heart disease, and cerebrovascular diseases.