Journal of Clinical Epidemiology 55 (2002) 749–755 0895-4356/02/$ – see front matter © 2002 Elsevier Science Inc. All rights reserved. PII: S0895-4356(02)00414-6 Can cardiovascular risk factors explain the association between education and cardiovascular disease in young women? Choon-Lan Chang a , Martin J. Shipley b , Michael G. Marmot b , Neil R. Poulter a, * a Cardiovascular Studies Unit, Department of Clinical Pharmacology, Imperial College of Science, Technology and Medicine, St. Mary’s Campus, London W2 1PG, UK b International Centre for Health & Society, Department of Epidemiology and Public Health, University College London, UK Received 27 March 2001; received in revised form 1 February 2002; accepted 4 February 2002 Abstract We sought to explain the observed variation in the relationship between education and cardiovascular disease (CVD) among young women in countries at different stages of economic development. Data comprised 2,478 cases of acute myocardial infarction (AMI) or stroke and 6,819 age- matched controls from Africa, Asia, Eastern Europe, and Latin America. The risks of AMI associated with lower education observed in Eastern Eu- rope and higher education in non-European countries were reduced by 92% in Eastern Europe and totally abolished in non-European countries by adjustment for standard cardiovascular risk factors. The inverse associations between education and stroke risk in the three non-African regions were attenuated by 22, 47, and 60% after adjustment. In Africa, the slight inconsistent trend towards lower stroke risk in less well educated women was unaffected by adjustment. These data suggest that standard risk factors explain a substantial proportion if not all of the difference in AMI risk associ- ated with education but a lesser proportion of educationally linked stroke risk. © 2002 Elsevier Science Inc. All rights reserved. Keywords: Acute myocardial infarction; Developing countries; Educational attainment; Risk factors; Stroke; Young women 1. Introduction The inverse relationship between cardiovascular disease (CVD) and socio-economic status (SES) in western societ- ies has been reported by many investigators in the last 2 de- cades [1–4]. However, the relationship between CVD and SES in developing countries remains inconsistent, depend- ing on the level of development [5–10]. Many investigators have reported that the SES-associated differences in CVD or mortality are only partly accounted for by differences in known standard risk factors [11,12]. We have examined the relationship between SES and CVD in women [13], but to our knowledge, none has sought to explain the observed re- lationship. Using data collected in the WHO Collaborative Study of Cardiovascular Disease and Steroid Hormone Contracep- tion [14–17], we investigated the role of classic risk factors in determining the apparent association between educa- tional level as a surrogate measure of SES and risk of acute myocardial infarction (AMI) and stroke in young women. 2. Subjects and methods The WHO Collaborative Study was a large international multicentre hospital-based case–control study, a detailed description of the methods of which has been previously published [17]. In brief, the main study was undertaken in 21 centers from 17 countries in Africa, Asia, Europe, and Latin America. Because of the small number of cases re- cruited in each country and the number of confounding vari- ables included in the regression analyses results are reported on a regional basis rather than by country. UK data were not included in the joint European analyses because: (1) of its mature market economy in contrast to the other European countries that are formerly socialist countries and do not have a market economy; and, (2) its distribution of cases and controls among the educational strata was significantly different from that of other European countries. Slovenia and the Federal Republic of Yugoslavia were considered as one country in these analyses and, hence, data from the four regions arise from 15 countries. Cases were incident cases of AMI and cerebrovascular accident (stroke) among women aged 20–44 years (15–49 years in the African region and Jamaica), who were admit- ted to one of the collaborating hospitals between February 1989 and January 1995. Stroke cases were classified as is- * Corresponding author. Tel.: +44-020-7594-3446; fax: +44-020- 7594-3411. E-mail address: n.poulter@ic.ac.uk (N.R. Poulter).