A major global study has found that the vast majority of heart attacks may be predicted by nine easily measurable factors which apply to virtually every region and ethnic group worldwide.
The INTERHEART study, one of the largest case control studies examining the importance of heart disease risk factors, looked at more than 29,000 people in 52 countries from all inhabited continents of the world. The study was coordinated by Dr Salim Yusuf, Professor of Medicine at the Michael G. DeGroote School of Medicine at McMaster University and Director of the Population Health Research Institute at McMaster University and Hamilton Health Sciences, Ontario, Canada. Aga Khan University (AKU), Karachi was the coordinating centre for Pakistan with five centres in Karachi, Hyderabad and Islamabad contributing nearly 1,400 subjects to the study. Dr Khawar Kazmi, Head, Section of Cardiology at Aga Khan University Hospital (AKUH), was the national coordinator.
The study found that the two most significant risk factors are cigarette smoking and an abnormal ratio of blood lipids (apolipoprotein B and A-I), which together account for two-thirds of the global risk of heart attack. Additional risk factors include high blood pressure, diabetes, abdominal obesity, stress, inadequate consumption of fruits and vegetables, and lack of daily exercise. Worldwide, these nine factors can collectively predict over 90 per cent of potential heart attack.
The INTERHEART study involved 15,152 individuals who had suffered one heart attack and 14,820 others who did not have heart disease but who were of the same age, gender and from the same city. This major study is the first examination of whether risk factors for heart attack have a similar or different impact on all major ethnic groups and major areas of the world. It included 4,000 South Asians, 7,000 people of European extraction, 2,000 from Latin America, 1,400 Africans, 6,000 Chinese, 3,500 Arabs and 2,000 subjects from other parts of Asia.
The INTERHEART study results were presented at the European Society of Cardiology (ESC) conference in Munich, Germany, in August 2004 and results were published in the prestigious medical journal The Lancet on September 11, 2004.
According to Dr Khawar Kazmi of AKUH, conventional wisdom had previously suggested that only half of the risk of heart attacks may be foreseen. However, the INTERHEART findings mean the overwhelming majority of heart attack risk may be predicted.
"These factors appear to predict the majority of the risk in virtually every region, every ethnic group, in men and women and in the old and the young," said Dr Kazmi. "This suggests that the message of preventing cardiovascular disease can be quite simple and generally similar across the world, after taking into account economic and cultural differences. "Since these risk factors may all be modified, this study will change the way we look at heart attack prevention. It means we should be able to prevent the majority of premature heart attacks in the world. This is a landmark study."
Dr Kazmi explained that the study suggests that a combination of lifestyle changes including smoking cessation, healthier diet and increased exercise could lead to an 80 per cent reduction in the risk of heart attacks," he said. "The INTERHEART study provides the research evidence needed to build national and international programmes for the prevention and control of one the leading cause of death in Pakistan and across the world."
Dr Kazmi added that the study is of great relevance to Pakistan. "This is the largest data study to date in Pakistan on the risk factors for acute heart attack and guides us in developing strategies for the prevention of the rising epidemic of coronary artery disease," he elaborated, urging the medical community, government and NGOs to join hands and work together for this cause. He also highlighted the initiative taken by AKU in the form of a Smart Heart Programme which has three major components:
- Increasing awareness of heart disease and healthy lifestyles among the general public;
- Continued educational activities for general practitioners which will help standardise patient care at the grass root level.
- Creating awareness of healthy lifestyles in school children.
In this connection, AKU's Smart Heart Programme is also celebrating World Heart Day on September, 26, 2004. The theme this year is 'Children, Adolescents and Heart Disease' and an education-cum-entertainment programme has been arranged on the day for school children at AKUH.
