By Sola Ogundipe, Chioma Obinna & Gabriel Olawale
As the global population rises over seven billion, a new report has shown that the number of deaths from hypertension, stroke, heart attacks and other circulatory diseases is on the rise, climbing from 12.3 million deaths to 17.3 million.
The report also showed that efforts to prevent and treat cardiovascular diseases appear to be working as the rise in deaths is slower than the overall growth of the population.
This is coming on the heels of a recent survey that shows that hypertension rates in Nigeria jumped from 11 per cent in 1997 to 40 per cent in 2013.
Globally, the number of deaths due to cardiovascular diseases increased by 41 percent between 1990 and 2013, climbing from 12.3 million deaths to 17.3 million deaths. Over the same period, death rates within specific age groups dropped by 39 percent, according to an analysis of data from 188 countries. Death rates from cardiovascular diseases were steady or fell in every region of the world except western sub-Saharan Africa, where the rates increased.
The study, published yesterday in The New England Journal of Medicine, and the “Demographic and Epidemiologic Drivers of Global Cardiovascular Mortality,” was conducted by researchers led by the Institute for Health Metrics and Evaluation, IHME, at the University of Washington.
The researchers noted that the progress in fighting cardiovascular diseases is evident around the world but varies by region.
According to them, South Asia, which includes India, experienced the largest jump in total deaths due to cardiovascular diseases, with 1.8 million more deaths in 2013 than in 1990 — an increase of 97 percent.
In line with global trends, the increase in deaths from cardiovascular disease in India is driven by population growth and aging without the decrease in age-specific death rates found in many other countries.
“This pattern is reversed to some extent in the Middle East and North Africa, which includes countries such as Saudi Arabia, Lebanon, and Jordan. In these regions, population growth and aging have been offset by a significant decline in age-specific death rates from cardiovascular disease, which has kept the increase in deaths to just fewer than 50 percent. East Asia experienced a similar rise of almost 50 percent, 1.2 million additional deaths, because declines in the risk of cardiovascular diseases offset the effect of a rapidly aging population.
“Taken together as a region, the United States and Canada were among a small number of places with no detectable change in the number of deaths from cardiovascular diseases, because aging and population growth balanced out declines in age-specific death rates. The same was true in southern Latin America, including Argentina and Chile, as well as Australia and New Zealand.
“Two regions— central Europe and western Europe—have managed to do what their global peers have not by significantly reducing not only the death rates but also the total number of deaths from cardiovascular diseases, which fell by 5.2 percent and 12.8 percent, respectively, between 1990 and 2013. When looking at cardiovascular death rates, the high-income Asia Pacific region, which includes Japan, achieved the greatest decline globally.
In the views of Assistant Professor at IHME from the Division of Cardiology at the University of Washington, Dr. Gregory Roth “Cardiovascular diseases will remain a global threat as the population grows and people age but the progress seen in some regions shows that reducing the toll of cardiovascular diseases is possible.”
Researchers found that population aging contributed to an estimated 55 percent increase in cardiovascular disease deaths globally, and population growth contributed to a 25 percent increase. These demographic factors are not the only drivers behind the trend of increasing deaths and falling death rates. Changes in the epidemiology of cardiovascular diseases are another factor.
Ischemic heart disease is both the leading cause of death worldwide and accounts for almost half of the increase in the number of cardiovascular deaths, despite a 34 percent decrease in age-specific death rates. Several other types of cardiovascular causes of death followed the same pattern, including aortic aneurysm, hypertensive heart diseases, and endocarditis, among others.
Two conditions that were exceptions to this pattern are atrial fibrillation and peripheral vascular disease, for which deaths have jumped significantly since 1990, due to both higher death rates within specific age groups as well as general aging and population growth.
Only rheumatic heart disease, which had a death rate decrease of more than 100 percent, had a lower number of total deaths in 2013 than in 1990; deaths fell by an estimated 27 percent over the 23-year period of the study.
Researchers also examined whether wealthier countries fared better than lower-income countries when it comes to cardiovascular deaths and found there was not a strong correlation between income per capita and lower age-specific death rates. The dramatic improvement in the death rates seen in some regions was attributed to prevention and treatment of cardiovascular diseases, in part by reducing risk factors including smoking. Primary care management of other risk factors for cardiovascular diseases, such as elevated blood pressure and blood sugar, are also important.
IHME Director, Dr. Christopher Murray however said: “Addressing the range of factors that contribute to cardiovascular disease will help ensure that fewer people around the world die from it prematurely. Investments and policies aimed at targeting preventable risk factors can reduce the impact of cardiovascular disease.”
Research shows that hypertension rates jumped from 11 per cent in 1997 to 40 per cent in 2013. A World Cardiology study conducted in Oyo, Katsina, Kwara and Enugu states, shows that estimates that the prevalence of people living with hypertension is about 27 per cent in Katsina, 36.6 per cent in Ilorin, 20.8 per cent in Ibadan rural, 46.6 per cent in Enugu rural.
Speaking on the issue, Emeritus Professor of Medicine at the University of Ibadan, Oyo State, Oladipo Akinkugbe, noted that unmanaged and undetected hypertension or high blood pressure was the major reason why more Nigerians were suffering and dying of stroke, heart disease and chronic kidney failure.
Akinkugbe blamed high salt content in local foods in the country for the trend. “If there is much salt, the kidneys pass it into urine. But when our salt intake levels through foods are very high, the kidneys cannot keep up and the salt ends up in our bloodstream. Salt attracts water. When there is much salt, it draws more water into the blood. More water increases the volume of blood, which raises blood pressure. “Akinkugbe who advocated a national salt-focused reduction therapy policy in the country, said Africans are more salt sensitive than their white counterparts
“The situation is worse today because the lifestyle and diet of the average Nigerian has changed. We eat more processed foods than ever, yet we are the ones suffering from the diseases they cause because of our genes.”
In the views of Associate Professor of Medicine, College of Medicine, University of Lagos, Dr. Amam Mbakwem, Nigerians suffer from the effects of high blood pressure due to ignorance.
Mbakwem, a cardiologist, argued that more than 60 per cent of Nigerians, who are hypertensive, do not know they have high blood pressure. Her words: “Many Nigerians with heart diseases do not know that they have high blood pressure till their hearts start failing. They wait for symptoms before they go for check up, which is deadly. For instance, if you have high blood pressure and you don’t know, by the time you are feeling dizzy or weak or breathless in the morning, some organs, such as the kidney and the liver, may have been damaged.”
“We are not just worried that the number of hypertensive patients is going up. We are more worried that Nigerians do not know how to manage it. The statistics has been going up in the last 15 years, yet there is no special plan to check it. High blood pressure is fatal to the heart, kidney and brain when left unmanaged.” Recent surveys show that heart and cardiovascular diseases are the leading causes of death in the world. Findings show that death rates are higher generally in developing countries, including Nigeria due to the late detection of cases and other risk factors such as high cholesterol, high blood pressure and smoking; diabetes, obesity and sedentary living.