Background and Objectives
Common diseases of public health significance such as diabetes mellitus, cardio-vascular disorders, and most cancers are multi-factorial in origin, often involving complex gene-environment interactions. Cohort studies are valuable for studying such diseases because they enable measurements of environmental exposure as well as collection of biological specimens are made prior to the onset of disease. Cohort studies also allow investigators to monitor numerous outcomes simultaneously. Furthermore, their value increases significantly with longer follow-up and repeated measures of exposure data.

Singapore's multi-ethnic composition presents an additional advantage as our local cohorts can provide valuable comparisons between the three major ethnic groups. For example, lung cancer incidence in Chinese male is 1.5 times higher than that of Malay males. Yet smoking is 1.8 times more prevalent in Malay than Chinese males. The risk of ischemic heart disease is 3 times higher in Indians than Chinese but their mean serum lipid profile is fairly similar. The reasons for such ethnic differences remain unclear but it is possibile that undetected gene-gene or gene-environment interactions are present. Adequate numbers of subjects in each ethnic group are critical to provide the statistical power required to explore these interactions.

Activities
The Singapore Consortium of Cohort Studies (SCCS) has been set up to establish the following:

1. An amalgamated cohort of normal individuals for the study of cardiovascular and metabolic diseases and selected cancers by combining three on-going studies which have very similar protocols. In addition, a new cohort of Indians will be recruited using the same protocol.
2. A prospective cohort of 10,000 diabetic patients to study the development of both macro- and micro-vascular complications.

Leadership

The SSCC is chaired by Professor Chia Kee Seng, Professor (Department of Community, Occupational Family Medicine, NUS); Director (Centre for Molecular Epidemiology, NUS); Senior Faculty (NUS Graduate School for Integrative Science and Engineering); and Adjunct Group Leader (Genome Institute of Singapore).