BACKGROUND: Cardiovascular disease is the leading cause of death and disability in older people, who account for an increasing proportion of Canada's population. Knowledge and awareness of risk factors is essential for changes in behaviour, yet little is known about these issues in older people. The Canadian Heart Health Surveys database provides a unique resource to examine knowledge and awareness of cardiovascular risk factors in older Canadians. METHODS: This descriptive cross-sectional study used data from the Canadian provinces' Heart Health Surveys, for the years 1986 to 1992. Sampling within each province consisted of stratified, 2-stage, replicated probability samples; 4976 people 55 to 74 years of age were included in the present analysis. Knowledge and awareness of cardiovascular risk factors was determined from the survey question "Can you tell me what are the major causes of heart disease or heart problems?" Blood pressure was measured during a home visit; anthropometric and blood measurements were obtained during a clinic visit. Cardiovascular health status was determined by self-reporting. RESULTS: Smoking and stress or worry were mentioned as major causes of heart disease by the greatest proportion of participants (41% and 44% respectively); hypertension was mentioned by only 16%. Men and women did not differ in their awareness of high blood cholesterol (cited by 23% of participants), smoking (41%), excess weight (30%) or lack of exercise (28%) as causes of heart disease. A greater proportion of women than men were aware of hypertension (19% v. 12%) and heredity (31% v. 17%) as major causes of heart disease. Awareness of risk factors was consistently lower in the older age group (65-74 v. 55-64 years). Among women, there was greater awareness of the respective risk factors as causes of heart disease among those who were smokers (60% v. 35% of nonsmokers), those who had a body mass index (BMI) of 25 or greater (38% v. 24% of those with a BMI less than 25) and those who were hypertensive (22% v. 17% of those without hypertension). Those who had experienced a heart attack had greater awareness of the major causes of heart disease than those who had not; this pattern was stronger among women than among men. Of those in whom elevated cholesterol level was identified during the course of the study, 62% of men and 67% of women were unaware of their cholesterol status. Of those in whom high blood pressure was diagnosed, 43% of men and 33% of women were unaware of their hypertensive status. INTERPRETATION: Awareness of the major causes of cardiovascular disease is low among older Canadians, especially among men and in those 65 to 74 years of age.