The Hordaland Homocysteine Study: Lifestyle and Total Plasma Homocysteine in Western Norway

The Hordaland Homocysteine Study is a cohort of approximately 18,000 men and women, ages 40–67, who had their total plasma homocysteine (tHcy) determined in 1992 or 1993. The long-term aim of the study is to relate plasma tHcy to future cardiovascular disease incidence, cause-specific, and all-cause mortality. In Norway, complete mortality follow-up is assured for all individuals who do not leave the country permanently, and the study will have access to mortality data kept at the Central Bureau of Statistics. Furthermore, we plan to register all hospitalizations for cardiovascular disease, including coronary angiographies, coronary surgery, and balloon angioplasties in the six hospitals that serve Hordaland. Complete cancer incidence data for the cohort members will also be available through the Cancer Registry of Norway, which keeps records of all cancer cases diagnosed in the country. No follow-up data are available yet, and so far we have focused on the study of cross-sectional associations between plasma tHcy and established cardiovascular risk factors and lifestyle.