Heart disease

Cardiovascular disease and risk factors

Cardiovascular disease remains the leading cause of death in Canada and is one of the major reasons for hospitalization. Cardiovascular disease is the main contributor to direct and indirect health costs ($18.5 billion in 1998, or 11.6% of the total cost of all diseases combined). And cardiovascular disease is preventable, for the most part, although doing so is a complex undertaking that requires action at multiple levels with objectives that vary in accordance with how the disease develops.

In Canada, mortality from ischemic heart disease has declined steadily since the 1960s. It is estimated that the decrease observed in Canada between 1970 and 1990 could be attributed to preventive measures (50%) and improved treatments (50%).

Numerous studies have identified the major risk factors associated with cardiovascular disease, and these factors have been described in various publications and reports. Among these is the report published by the Heart and Stroke Foundation of Canada in May 2003, entitled “The Growing Burden of Heart Disease and Stroke in Canada”. This document reports that approximately 80% of the population presents at least one modifiable risk factor for cardiovascular disease. Although it is impossible to modify age, sex and family history, it is possible to take action against the other risk factors such as smoking, physical inactivity, excess weight, high blood pressure, high cholesterol, diabetes (type 2) and stress. Here is how the report qualifies the various risk factors.

Smoking

Smoking is the leading cause of preventable death in Canada and increases the risk of developing all major forms of cardiovascular disease. Smoking is the leading cause of cardiovascular diseases and is therefore considered the No. 1 killer in the United States and Canada. It is estimated that 26% of the Québec population smokes (men and women aged 15 years and older), which represents 1.7 million people. In this group, one out of two people will die from an illness related to this habit; losing an average of 10 years of life expectancy. More than 13,000 Quebeckers die from a smoking-related illness each year; 25% to 30% of these deaths are related to cardiovascular diseases. Most studies suggest that anti-smoking counselling is extremely effective and an essential element of any therapy aimed at helping a person who is trying to stop smoking. In recent years, a significant number of smokers have managed to put an end to their dependency thanks to Québec's anti-smoking strategies. Among these is the ban on smoking in the workplace and the success of the "Quit to Win Challenge". In 1994 and 1995, between 36% and 38% of Quebeckers were smokers. According to a Health Canada cohort study, accepted as an authority at the time, this percentage decreased to approximately 36% in 1996-1997, and was around 34% in 1999.

Physical inactivity

Excess weight

The majority of industrialized countries are currently struggling with an epidemic of obesity and type 2 diabetes among both adults and children. Being overweight, either excess weight or obesity, is one of the most common factors influencing the development of high blood pressure and diabetes, two important risk factors for cardiovascular disease. In general, balanced nutrition and regular physical activity can reduce excess weight and obesity. Often, however, the treatment is associated with a pattern of weight loss and weight gain, necessitating a multidisciplinary approach involving doctors, nutritionists and other healthcare professionals.

Inadequate consumption of fruits and vegetables

Daily consumption of 5 to 10 servings of fruits and vegetables is associated with a reduced risk of cardiovascular disease. This benefit is related to the intake of natural vitamins, antioxidants and natural fibre.

High blood pressure

High blood pressure is a major risk factor for stroke and coronary artery disease, peripheral vascular disease and congestive heart failure. It increases cardiovascular risk by two to three times. According to authors G. Paradis and C. Thivierge, treating high blood pressure is based on lifestyle modification: adopting a healthy diet that is balanced and low in salt; engaging in physical activity; reducing alcohol consumption; and, stopping smoking.

Dyslipidemia

Abnormally elevated cholesterol, low-density lipoproteins (LDL) and triglycerides, and low levels of high density lipoproteins (HDL) are important risk factors for the development of vascular disease, particularly for coronary artery disease. “According to the 1985-1990 Heart Health Surveys, 45% of men and 43% of women had a total plasma cholesterol level above the desirable level of 5.2 mmol/L.”

Diabetes

Adult onset diabetes is a significant risk factor for the development of high blood pressure, stroke, and heart and vascular disease, particularly in women.

The authors agree that prevention must begin in childhood, with good nutrition and physical activity. For adults, prevention is geared towards those in good health, but who present risk factors and, obviously, those who have already suffered a heart attack, to reduce their risk of having any subsequent attacks.

Moreover, in the discussion section of the chapter on risk factors, the Canadian Heart and Stroke Foundation states, “unless community interventions with a sufficient preventive impact are implemented, the cardiovascular epidemic will continue.” In fact, it seems that the decreased morbidity attributable to cardiovascular diseases mentioned earlier in the text is beginning to reverse. According to many specialists in the field of cardiovascular prevention, the incidence of cardiovascular disease will increase in years to come given the increasing obesity among children, adolescents and even young adults.

Finally, it is important to point out that the lifestyle modifications recommended for preventing cardiovascular disease are the same as those recommended for preventing cancer.

References:

• Economic Burden of Illness in Canada, Health Canada, 1998
• The Growing Burden of Heart Disease and Stroke in Canada, Canadian Heart and Stroke Foundation, May 2003
• Paradis G., Thivierge C., Cardiovascular diseases. Risk factors. Prévention en pratique médicale, Newsletter of the Montréal Public Health Department, 2nd quarter 2004
• Info-tabac, No. 37, September-October 2001