THE global rise in the prevalence and mortality of cardiovascular diseases (CVD) over the past 30 years is thought to indicate the real world outcomes of the profound income inequality and health inequity within communities resulting from the unmet need for affordable interventions.
This inequity is compounded by patients' risk factor level, education and health policies.
In a recent report evaluating data from 204 countries and territories in the Global Burden of Cardiovascular Disease Collaboration, the investigators identified Central Asia and Eastern Europe as epicentres of the CVD epidemic with the highest rates of CVD mortality. Furthermore, the report identified hypertension, dietary indiscretion, high cholesterol, and air pollution as the leading causes of CVD globally. The recognition of air pollution as a leading cause of CVD globally is an area that has received scant attention. Starting from the new year, we intend to do a series of articles on air pollution and CVD to highlight this important but neglected cause of CVD.
In high-income regions of North America the researchers found that age-standardised CVD mortality rates ranged from 102.1 to 224.8 per 100,000 in 2021, reflecting a 2.6-fold difference. Hypertensive heart disease had the largest per cent increase in CVD cause-specific, age-standardised mortality rates since 1990 (53.3 per cent), whereas rheumatic heart disease had the largest per cent decrease (61.2 per cent).
Ranking of modifiable risk factors
The analysis of the Global Burden of Diseases, Injuries and Risk Factors study provide a useful ranking of modifiable risk factors associated with these trends in CVD and mortality:
• High systolic BP
• High LDL-Cholesterol
• Air pollution
• High body mass index (BMI)
• Tobacco smoking
• High blood glucose
• Kidney dysfunction.
According to the analysis, rheumatic heart disease, fuelled by poverty and crowded housing conditions, as well as alcoholic cardiomyopathy fuelled by excessive alcohol consumption, are also potential targets for CV risk reduction.
Global prevalence of CVD and mortality
Globally, the total number for CVD nearly doubled over the past 30 years from 271 million in 1990 to 523 million in 2019, and CVD deaths increased from 12.1 million in 1990 to 18.5 million in 2019, affecting men and women almost equally (9.6 million men: 8.9 million women), according to the analysis. Approximately 6.1 million premature deaths from CVD were noted in individuals aged 30 to 70 years, representing 33 per cent of CVD deaths worldwide. Additionally, CVD was the underlying cause of death among approximately one-third of all deaths globally. CVD prevalence is likely to increase substantially as a result of population growth and ageing, especially in low-resource communities including much of Africa, Asia, Latin America, and the Caribbean where the share of older persons is projected to double between 2019 and 2050. Increased attention to promoting ideal cardiovascular health and healthy ageing across the lifespan and population segments must therefore form part of the national policy thrust for managing the expected increase in CVD in the coming years. We look forward to working with the Government and other responsible parties in proactively designing mechanisms to address this problem in a way that ensures health equity consistent with the One Health initiative being promoted by the Minister of Health Dr Christopher Tufton.
Disability-Adjusted Life Years (DALY)
The report also looked at disability-adjusted life years, the years of life lost due to premature mortality, and years lived with disability. By summing the DALYs in a population, we can discover which populations are living with the greatest health burden and prioritise those areas for future health interventions. The main advantage is that DALYs provide a composite, internally consistent measure of population health which can be used to evaluate the relative burden of different diseases and injuries, and provide comparison of population health by geographic region and over time. The overall burden of disease is assessed using the disability-adjusted life year (DALY), a time-based measure that combines years of life lost due to premature mortality (YLLs) and years of life lost due to time lived in states of less than full health, or years of healthy life lost due to disability (YLDs). DALY is a very useful assessment of quality of life rather than simply measuring the length of life. Next to ischemic heart disease and stroke, the collaborative investigators found that hypertensive heart disease had the highest age-standardised DALY rate of 226.4. Among all CVD risks, hypertension accounted for the largest proportion of DALYs at 40.5 per cent. Globally, the report noted that ischemic heart disease is the leading cause of CV death, accounting for 9.44 million deaths in 2021 and 185 million DALYs.
Hypertension is a leading modifiable risk for CVD
Hypertension is the leading modifiable risk factor for CV death. High blood pressure remains the key risk factor driving the global rise in CVD mainly through the causation of hypertensive heart disease, coronary artery disease and stroke. According to the Jamaica Health and Lifestyle Survey for 2016/2017, one in three Jamaicans are hypertensives, including nearly 40 per cent of women. More worrisome is that four out of every 10 hypertensives are unaware of their status, 60 per cent of whom are men. Another study from the Imperial College of London notes that more than 80 per cent of hypertensives globally account for about one billion people live in low- and middle-income countries.
In individuals at risk, treatment to lower blood pressure is a remarkably effective strategy to delay progression to cardiovascular complications including heart attacks, strokes, kidney failure and heart failure. When initiated in middle age, intensive blood pressure control is predicted to prolong life expectancy by up to three years. In light of the evidence, there is a great urgency in driving public health strategies to promote early screening, detection, and treatment of hypertension. Affordable and cost-effective approaches must be explored to expand access to include individuals in remote, rural, and low-income communities. Effective strategies currently exist leveraging mobile technology and remote patient monitoring to expand access, and these approaches must be embraced in low-resource nations and communities to address a clear and present danger. Individuals at risk can be evaluated in real time, and early signs of cardiovascular damage can be identified with simple techniques like electrocardiograms (ECGs). Affordable technology currently exists to provide electrocardiograms daily — with cardiologist interpretation in real time in all public health centres in all 14 parishes — and we would be happy to assist the Ministry of Health and Wellness in getting this done. Once identified, treatment approaches must consider the use of polypills for hypertension and other CVD promoters as these have been demonstrated to be highly cost-effective and efficacious, especially in individuals and communities with financial constraints.
Dr Ernest Madu, MD, FACC and Dr Paul Edwards, MD, FACC are consultant cardiologists for the Heart Institute of the Caribbean (HIC) and HIC Heart Hospital. HIC is the regional centre of excellence for cardiovascular care in the English-speaking Caribbean and has pioneered a transformation in the way cardiovascular care is delivered in the region. HIC Heart Hospital is registered by the Ministry of Health and Wellness and is the only heart hospital in Jamaica. Send correspondence to email@example.com or call 876-906-2107