The prevalence of heart disease and certain key risk factors — hypertension, diabetes, and obesity — are increasing in all age groups and most income groups in Canada found a new study published in CMAJ (Canadian Medical Association Journal) http://www.cmaj.ca/press/cmaj081629.pdf (www.cmaj.ca). This study, which looked at national data from 1994 to 2005, encompassed people aged 12 years and older sampling from Canadians of all socioeconomic and ethnic groups. Risk factors such as hypertension, diabetes, and obesity increased most rapidly among younger people between 12 to 50 years of age.
The increasing prevalence of heart disease in Canada is likely related to both earlier detection and better survival among those with cardiovascular disease. More Canadians are surviving their first heart attack. The prevalence of heart disease is rising fastest among Canadians of lower socioeconomic status, who also tend to have the highest cardiovascular risk profiles.
This increase in risk factors in younger Canadians has significant health implications because it predisposes people to earlier onset heart disease. It can place greater burden on health care resources as younger people may need longer, and perhaps more intense, treatment.
The study found an estimated 1.29 million Canadians reported having heart disease in 2005, a 19.3% increase in men and 2.1% increase in women compared with 1994. Although people who were of lower socioeconomic status had the highest risk factor burden, hypertension prevalence nearly doubled and obesity increased over time in all socioeconomic groups. Diabetes is also increasing in almost all income groups, although the gap between the richest and the poorest is widening over time.
The authors found that hypertension and diabetes are increasing most in those who were obese or overweight. “Projections suggest that the rising prevalence of obesity in the current generation of adolescents will increase the prevalence of coronary heart disease by 5 to 16% in 2035, and may for the first time in 2 centuries significantly reduce life expectancy in the 21st century,” state Dr. Douglas Lee of the Institute for Clinical Evaluative Sciences (ICES) and coauthors.
“This study has implications for all Canadians because the surveys were conducted in a representative sample of the Canadian population, including all ethnic groups,” write the authors. “Our findings draw attention to risk factors in early adulthood, which predict cardiovascular disease of early onset and are associated with greater need for health care resources in the last years of life.”
Interventions to encourage healthy eating, exercise and provision of preventative medications such as smoking cessation therapy in at-risk groups may help reduce widening disparities between the highest and lowest socioeconomic groups.
The study was conducted by researchers from the Institute for Clinical Evaluative Sciences, University Health Network, University of Toronto, Sunnybrook Health Sciences Centre, Toronto; Queen’s University, Kingston, Ontario; University of Alberta, University of Calgary, Alberta; Dalhousie University, Halifax, Nova Scotia; and Statistics Canada. It was funded by the Canadian Institutes of Health Research (CIHR).
The declines in mortality associated with heart disease may be at an end, writes Dr. Annika Rosengren of Sahlgrenska Academy, Goteborg, Sweden in a related commentary http://www.cmaj.ca/press/cmaj090911.pdf. The decline in rates for young people in England, Wales and the US has begun to level off and may also be happening in Canada. She argues for action that focuses broadly on societal changes to fight obesity such as healthy eating and exercise.