Introduction
Cardiovascular diseases (CVDs) are recognized as among the leading causes of health and economic burden, not only in Australia but also globally (O’Neil et al., 2012). CVD is a generic term describing a multiplicity of diseases that results from inadequate blood flow to the heart, primarily caused by the constriction of the coronary arteries due to atherosclerosis. Myocardial infarction (MI), according to Joynt et al (2009), is the most persistent form of CVD and occurs when a section of the heart muscle dies or is lastingly damaged due to insufficient supply of oxygen to that section triggered by a continued obstruction in a coronary artery. The present paper aims to explore and analyze how MI is currently affecting the Australian population.
Exploration & Analysis of MI in Australia
Population/Community affected by MI
Extant literature demonstrates that not only are men at a higher risk of MI than women, but they are more likely to become victims at a relatively younger age (BigPond, n.d.). Loughnan et al (2008) suggest that although men and women aged over 70 are at an elevated risk of being affected by MI, around 75 percent of recorded heart attacks are in male patients, but their predisposition diminishes with advancing age. In contrast, menopausal women record higher rates of MI than younger women due to lack of estrogen, which is known to reduce the build-up of plaques in blood arteries (Ioannides-Demos et al., 2010).
Extending work in this nascent area of research, Hunter (2010) claims that indigenous people of Australia (Aboriginals) have the greatest excess mortality and morbidity from MI. This fact is reinforced by an Australian report on CVD, which suggests that “…mortality from all cardiovascular diseases was highest in the Northern Territory at 3,900 and 2,426 deaths per million population for males and females respectively in 1994-96” (Overview of Current Trends, n.d., p. 9). The higher mortality rate in the Northern Territory, according to this report, can be attributed to the fact that aboriginals and other indigenous people form a large part of the population compared to other regions in Australia. Overall, according to Ioannides-Demos et al (2010), the Australian population mostly affected by MI is aged between 25 and 84 years.
Scope & Implications of MI in Australia
Acute myocardial infarction (AMI) can be delineated as the detection of elevated values of cardiac biomarkers (preferably troponin) above the 99th percentile of the upper reference limit (URL) with one or several of the following: a) ischemic symptoms, b) electrocardiographic (ECG) shifts indicative of new ischemia (new ST-T changes or the new left bundle branch block), c) development of pathological Q waves in ECG, and d) imaging evidence of new loss of viable myocardium or the new regional wall motion abnormality (Jaffe, 2008). MI, according to this author, can also be defined in terms of unexpected cardiac death, including cardiac arrest, with symptoms reminiscent “…of myocardial ischemia, accompanied by new ST elevation, or new LBBB [left bundle branch block], or definite new thrombus by coronary angiography but dying before blood samples could be obtained, or in the lag phase of cardiac biomarkers in the blood” (P. 1486). It is important to note that although AMI is a major contributor to ischemic heart disease mortality in Australia because it is responsible for 60 percent of ischemic-related deaths, mortality resulting from AMI has been declining slightly faster than ischemic heart disease at an annual rate of 5.5 percent and 4.7 percent for males and females respectively (Overview of Current Trends, n.d.).
In terms of scope, it is reported that the most recent guidelines recognize five distinct variants or types of MI (Jaffe, 2008). Type 1 is an impulsive MI due to severe plaque rupture or erosion, implying that it characterizes as the typical ST elevation or non-ST elevation MI (Jaffe, 2008). This particular author conceptualizes Type 2 MI as “…secondary to an imbalance between oxygen supply and demand which may occur when one has fixed coronary disease and tachycardia, due to anemia or drug overdose, and at times can be related to concurrent abnormalities in coronary vasomotion” (p. 1487).
Type 3 MI is demonstrated in an individual “…with a classic MI with verified thrombus by angiography or at autopsy who dies before a troponin measurement being obtained or, if obtained, before a rise can be observed” (Jaffe, 2008, p. 1487). Type 4 MI, according to recent guidelines, is directly linked to percutaneous coronary interventions either in terms of the procedure itself or hinged on subsequently verified stent thrombosis. Lastly, Type 5 is a heart condition that generally occurs as a direct result of coronary bypass graft surgery (Jaffe, 2008). Majority of patients who die from MI in Australia develop ventricular fibrillation, which occurs soon after the onset of ischemia but before they can seek medical attention (O’Neil et al., 2010).
MI has far-reaching implications for the affected population. In Australia, as in other countries, MI forms a massive burden of care, in terms of morbidity, mortality, and economic cost (Chew et al., 2007). Although the incidence of CVD has been decreasing in Australia going to data released by various government agencies, the predictions still indicate that CVD and MI will constitute the major burden of disease in the country in the foreseeable future (O’Neil et al., 2012). In 2003, as reported by Ioannides-Demos et al (2010), CVD contributed considerably to the mortality and morbidity of the Australian population, accounting for an estimated 18 percent of the total burden of disease. These authors further observe that in 2006, one-third of all deaths in Australia were directly related to cardiovascular incidences, whereas AMI and angina pectoris accounted for almost half of over 45,000 CVD deaths recorded in 2005. These statistics demonstrate that MI is not only a common health problem in Australia, but is a serious and life-threatening condition (BigPond Health, n.d.).
Most survivors of MI are rendered unproductive or underproductive due to the nature of the illness and the high risk of recurrent heart attacks (O’Neil et al., 2012). Apart from this loss of individual productivity, society, in general, suffers from loss of productive members and the economic costs of the disease burden (O’Neil et al., 2010), as the disease is known to kill most of its victims as it progresses (BigPond Health, n.d.). This implies that society is not only burdened with the cost of bringing up the children of people who succumbs to MI but is forced to develop mechanisms to sustain the surviving patients who have been rendered morbid by the condition. Furthermore, the costs involved in managing MI have skyrocketed over the years, with available literature demonstrating that the cost for a MI in 2004-2005 ranged between $A3047 and $A9154 (Ioannides-Demos et al., 2010). This implies that the affected people are often prevented from achieving social and economic advancement as they routinely use considerable sums of money for hospitalization and treatment. Lastly, MI is associated with increased stress and depression (O’Neil et al., 2012), implying that the affected population is forced to put up with low-quality life due to the depressive state of mind and emotional drain.
Social Determinants of Health
According to Lang et al (2011), social determinants of health are basically the social conditions in which people interact on daily occasions in their work and relationships, not mentioning that these conditions, which are much on an international and national level as on a local level, are greatly informed by the allocation of power, income and critical resources. Social determinants of MI, therefore, are mostly found outside the scope of healthcare and preventive healthcare systems (Anand et al., 2008), but within the management of traditional risk factors associated with the condition.
Accordingly, it can be argued that apart from the known traditional risk factors of MI such as high blood pleasure, poor eating habits, environmental factors, sexual activity, elevated cholesterol, smoking, diabetes, and physical inactivity (Muller-Nordhorn & Willich, 2007), as well as abnormal lipids, abnormal obesity, hypertension, diabetes, alcohol use, and psychosocial stress factors (Anand et al., 2008), there exist other social determinants of MI such as working conditions, housing, and interpersonal relationships (Lang et al., 2011). Indeed, these authors have proved that some social determinants, including stressful work, unemployment, job instability, social isolation, polluted geographic location, discrimination, and ethnicity, are directly or indirectly linked to the development of MI risk factors.
Conclusion
The paper sought to explore and analyze how MI is currently affecting the Australian population. It can be concluded that men, menopausal women, and aboriginals have a higher risk of MI. Although recent guidelines recognize five distinct types of MI, many victims of MI in Australia develop ventricular fibrillation, which occurs soon after the onset of ischemia but deteriorates before victims are able to seek medical attention. MI forms a massive burden of care in Australia in terms of morbidity, mortality, and economic cost. Lastly, the social determinants of MI include working conditions, unemployment, housing, interpersonal relationships, as well as discrimination, and ethnicity.
References
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