Cardiovascular disease: risk factors in older Canadians

David R. MacLean, MD

CMAJ 1999;161(8 suppl):S1

Cardiovascular disease is an important cause of death, premature death, morbidity and years of potential life lost in Canada. The various conditions encompassed by this term are the leading causes of disability, loss of productivity and deterioration in quality of life among both men and women in this country. The care of people with these conditions uses up a large share of the budget devoted to health care in all provinces. Estimates suggest that cardiovascular disease costs the Canadian health care system approximately 17 billion dollars annually.¹ Clearly, cardiovascular disease is a major public health problem in Canada, one that creates a heavy burden in social and economic terms.

For countries such as Canada, there is some good news. The rates of cardiovascular disease and associated sequelae have been falling substantially over the past 2 decades, declining as much as 50% in some subpopulations.² This decline has been particularly pronounced for death caused by stroke. Canada has done very well in this regard, and our stroke rates are now among the lowest in the world.³ The reasons for the decline in the rates of cardiovascular disease are far from clear. However, evidence suggests that the reductions result from declines in both the incidence of disease and case fatality rates^4,5 -- the former presumably being the result of preventive efforts and the latter the result of improvements in medical care.

However, we should not take too much comfort from these trends. Despite the declines, cardiovascular disease is still the leading cause of death and disability in men and women, as well as the leading cause of premature death. Perhaps more important is the likely impact of changing demographics in Canada as the population ages. It is worthwhile to note that people at the leading edge of the baby-boom generation are just now entering the years when chronic diseases typically develop. Therefore, even with rates of cardiovascular disease continuing to decline, the absolute numbers of cases of heart disease and stroke will probably increase, perhaps dramatically, in the early part of the next century. If this situation develops, there will almost certainly be a significant increase in the demand for acute care related to these diseases and a concomitant increase in the need for acute care personnel and facilities. These increases will in turn add further to the costs of care in the already financially strained health care sector.

The papers presented in this supplement^6,7 provide specific information about the epidemiology of cardiovascular disease in older Canadians. The data come from the Canadian Heart Health Surveys database, an integrated data set derived from the provincial heart health surveys, which were conducted in every province of Canada according to a common protocol developed in Nova Scotia.⁸ The establishment and maintenance of this database has been an integral component of the Canadian Heart Health Initiative, a Canada-wide research and development program funded jointly through research grants from the National Health Research and Development Program of Health Canada and program grants from the provincial departments of health. The initiative is a unique undertaking for the prevention and control of heart disease and the promotion of heart health. It uses a public health approach, promoting action on the determinants of heart health through a partnership model, mainly at the community level.⁹

Much has been learned over the past 30 years about the epidemiology of cardiovascular disease, and during this period many of the important risk factors have been identified.¹⁰ As Donald Langille and associates report in this supplement,⁶ large numbers of Canadians 55 to 74 years of age have significantly elevated levels of the individual modifiable risk factors for cardiovascular disease. Research has also shown that cardiovascular disease is a multifactor disorder that results from a complex interaction of a number of risk factors leading to atherosclerosis and the formation of atheromatous plaque. Langille and associates⁶ also demonstrate that clustering of risk factors is widespread in people 55 to 74 years of age, with over 96% of this population having one or more of the major risk factors for cardiovascular disease. Clearly, widespread risk is at the root of the widespread prevalence of disease in this age group.

One of the major strategies commonly employed for the prevention and management of cardiovascular disease has been educating patients and the public. Although this approach does not guarantee changes in behaviour on the part of individuals, it is generally viewed as an essential ingredient in the process of change. In the other paper in this supplement, Susan Kirkland and colleagues⁷ demonstrate that there is much to be done in this regard. Individual knowledge concerning the risk factors for cardiovascular disease is poor, and it appears that older Canadians do not know enough about cardiovascular disease to help themselves.

Given the results of the analysis presented in this supplement, what should be done with respect to cardiovascular disease and older Canadians?

Epidemiological and community research over the past 30 years has shown, in a convincing manner, that cardiovascular disease is preventable, or at least its occurrence can be postponed.^11,12,13 These research observations have laid the foundation for a general scientific consensus that enough is known to take action on cardiovascular disease now and that reducing risk levels is cost effective.^14,15 To reduce risk, effective and practical programs are needed. One of the benefits of targeting cardiovascular disease as an entry point to issues of prevention and control of noncommunicable disease is that many of the risk factors associated with heart disease are also associated with other major chronic diseases such as cancer and diabetes. Therefore, an integrated approach to prevention will have a beneficial impact on many conditions. In addition, from a practical perspective, there is now a large and readily available constituency concerned with cardiovascular disease in Canada who are prepared to come together to address this issue.

Central to activities for controlling cardiovascular disease is the aim not only to extend life expectancy but also to influence health expectancy by improving people's quality of life. In practical terms this means the prevention of premature death and disability -- what has been referred to as "squaring the mortality curve and compressing morbidity." There is good evidence to suggest that these goals are indeed attainable and that people who have healthful lifestyles not only live longer, but also suffer less disability and consume fewer health care resources throughout their lives.^16,17,18

The data presented in this supplement show that there is much to be done if we are to lessen the burden of cardiovascular disease among older Canadians. Cardiovascular disease is a public health problem of the first order in this country, one that requires a comprehensive public health approach for its remedy. Such an approach requires that prevention and control become priorities not only for the health care system but also for all sectors of society that have a bearing on health.

Competing interests: none declared.

Address correspondence to: Dr. David R. MacLean, Department of Community Health and Epidemiology, Faculty of Medicine, Dalhousie University, 5849 University Ave., Halifax NS B3H 4H7; fax 902 494-1597; David.MacLean@dal.ca

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