This article is a summary of the 10-year multinational collaborative WHO/IS
FC Study of Pathobiological Determinants of Atherosclerosis in Youth (PBDAY
Study). Details are provided of the study design, relevant results, conclu
sions, and recommendations, as formulated at a consultation of the heads of
PBDAY Reference Centres, held in Budapest, Hungary, in October 1996. The W
HO/ISFC study provides unique information about the determinants of atheros
clerosis and structural changes in the arteries, especially during their ea
rly stages, and their progression from early life in populations with vastl
y different lifestyles. The pilot study covered subjects aged 5-34 years, o
f both sexes, from 18 centres in 15 countries, while the main study covered
11 centres in 11 countries. Included were both developed and developing co
untries with different economic, sociocultural and nutritional patterns fro
m five WHO regions. Collected was background epidemiological information, i
nformation about cases, and special studies of arteries using various morph
ometric methods and specialized techniques. Atherosclerotic lesions start t
o 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 a
ge, while raised lesions begin developing slowly during the second decade o
f life, progressing steadily during the third and more rapidly during the f
ourth. Fatty streaks are more prevalent among females and raised lesions am
ong males. The prevalence and extent of raised lesions were greater in coun
tries with a high prevalence of known risk factors and high mortality rates
for cardiovascular diseases, coronary heart disease, and cerebrovascular d
iseases.