07 April 2018
THE IMPACT OF ENVIRONMENT ON THE HEART
Environmental cardiology is the impact of the environment on the science of cardiology.
We are aware of certain factors that have the reputation of increasing the risks of a heart disease to surge. These factors are grouped under two categories; the non-modifiable risk factors and the modifiable risk factors.
The non-modifiable risk factors are: males, age and hereditary background.
The modifiable risk factors are: smoking habits, inactivity, obesity, diabetes and high blood pressure.
We now know that there is one more modifiable risk factor that has to be added to the list. And, it’s a big one. It’s our milieu, our environment.
From the coronary stake to the tree stake
Nowadays, we can instantly be aware of anything that happens around the World because of information globalisation. The same goes with the compilation of the statistics of deaths related to certain diseases.
The information may be compared between one region and another, between a country and another.
This is why we can see the differences between the number of people suffering from sicknesses and the deaths related to the heart in these different regions.
Questions arise. Why is it that there are less people from a certain area versus another area that are suffering from these diseases or that die from heart complications? The differences in eating habits and the impact of the environment are now well known.
Let’s see why this is so.
Important differences in cardiovascular mortality between countries
A stunning diagram presented by the World Health Organization shows that Russian and Ukrainian men (25-64 years of age) have a cardiovascular mortality rate 11 times greater (1100% !!) than Swiss and Spanish men.
This monstrous difference confirms that the traditional risk factors are not the only cause of this high rate.
Traditional risk factors
The individual risk factors of the coronary disease are well identified: family background, tobacco, diabetes, hypercholesterolemia, hypertension, obesity and inactivity.
In traditional medicinal school, the family and individual factors are well characterized. But, it is just recently that we are interested in environmental factors.
Industrial revolution = increase in cardiovascular mortality rate
Taking a step back, we realize that a cardiovascular disease was less frequent in the pre-industrialized era. In fact, from 1900 to 1950, the number of heart attacks quadrupled in the USA.
Humans who live away from the industrialized world are also less affected.
Through time and space, each industrial revolution saw an increase in the cardiovascular mortality rate.
The main environmental responsible: aerial nano-aggressors, very small-aggressors (pollution particles), food nano-aggressors (industrialized additives), urban mineralization, or wall to wall concrete.
Air pollution is responsible
We had to wait until March 2014 for the World Health Organization (WHO) to reveal that 7 million deaths are accountable to air pollution, or one out of eight deaths worldwide.
We evidently think of developing countries as main victims.
However, it is important to remember that in Canada (2008), it was estimated that 20 000 too many deaths occurred than what was “normally” expected and that 9.1 billion dollars were spent in health care because of the environment.
How to calculate the death “surplus”
The “extra” deaths, or the deaths that shouldn’t have been, are the difference between the expected deaths and the actual amount of deaths in a group of the population suffering from a heart disease.
We calculate the expected number of deaths according to the number of people who have a cardiovascular sickness and the normal mortality rate.
For example, if the mortality rate for a heart disease is 5% per year, for 1000 people suffering, the expected deaths are 50.
In the case where 75 people die in a year, the exceeding amount is 25 people.
Oxidant stress and inflammation
The atmospheric pollutants that increase heart attacks, strokes and sudden deaths are now well documented.
Let’s name them “oxidant stress” and associated inflammation.
If we vulgarize “oxidant stress”, we could say that the cells have small nuclear plants to build their energy. These small plants produce pollutants that we call free radicals.These are responsible for the oxidant stress, the counter-poison is the antioxidants that we hear more and more about.
The problem here is the unbalance between the production of the free radicals and the availability of the antioxidants.
Improvement in air quality works
A recent and historical victory: in 2014, Montreal and Toronto have a smog-free summer for the first time since tests are done. The University of Toronto estimated that with the improvement in the quality of air, there has been a reduction of exceeded deaths due to pollution (1300 compared to 1700 in 2004) and that there were less overnight hospitalizations (3550 compared to 6000).
Experts mainly attribute this to the closing of coal industries and to the “Drive Clean” program in Ontario.
A similar victory took place in the 80s. With the regulated eradication of lead in gasoline, the level of ambient lead was so greatly reduced that the Air Quality Surveillance Network in Montreal doesn’t measure it anymore.
But there is still lots to be done: only one of three days is considered “good” (air quality index <25) in downtown Montreal.
A recent study conducted in Boston by Harvard University demonstrates that when air quality goes from “good” to “acceptable” (AQI 25-50), there is a 35-50% increase in strokes.
The Chicago Medicine from October 2014 quotes this estimation from the Environment Protection Agency (EPA): each dollar invested to conform to the “Clean Air Act” cuts $25 from the health costs.
Food “pollution” is also responsible
With the aerial nano-aggressors emitted by flammable fossils, nano-aggressors in food appeared in our everyday life: industrial food additives.
Among the multitude of new molecules, three in particular bring their share of complications: omnipresent salt excess, Trans fat and added industrialized sugars.
The massive diffusion of these molecules causes high blood pressure, dyslipidemia, metabolic syndrome (almost diabetes), obesity, and heart attacks and strokes.
Atmospheric pressure aggravates these aggressions.
Associations often send memos and watchwords that are useless because of a lack of efficient jurisdiction, and because of the 30 000 publicity messages on fast-food that a child will see before adulthood, without mentioning soft drink distributors in schools that luckily are being removed and their proximity with the fast-food restaurants.
Air pollution and food potentiate
The conjunction of pollution and of industrialized food adds up and leads to the perfect vascular storm in our arteries.
Researchers have demonstrated that mice exposed simultaneously to fat food (of fast-food type) and to pollution develop massive atherosclerosis plaques in their aortas.
Industrialized food and pollution potentiate.
Concrete urban milieu
Furthermore, the urban milieu expands, mineralizes, or leaves little or no green areas, and new constraints appear: urban-heat islands, smog peaks, absence of a vegetation cover that tempers and filters the air, runoff and drainage problems.
In 2003, a climatic wake-up call occured in Europe: 70 000 “extra” deaths during the August heat wave, 20 000 of these in France especially in urban milieus with few green areas.
In Paris, the morgues cannot suffice, as corpses are placed tightly in meat refrigerators.
This is an unreal situation in this country considered by the WHO as having the best health system.
For a climatic event, life expectancy shortens in France for the first time since World War II.
The concept of urban heat island gains interest.
The importance of the green milieu
With new regards on deforestation, we realize that we have cut down half the forests on Earth.
We also realize the importance of trees in our urban areas, in all aspects of our lives: beauty and harmony, psychic and physical well-being, climate temperance, reduction of energy costs in buildings, air purification, extraction and metabolism of pollutant molecules.
Hundreds of studies explain the positive effects of trees in our environment, the most spectacular being the Scottish that wanted to measure the impact of green areas on health.
On the 40 million British subjects in the study, we observed 6% less deaths because of cardiovascular difficulties in green areas in only 5 years of tracking.
Three mechanisms are possible to explain this: less pollution in green areas, filtration and purification of the air through the trees, a positive, beneficial action of the arboreal proteins on our organism.
Solution mode. Hospitals first.
If a city eradicates its aerial and food nano-aggressors and promises for a green and active milieu, this city can wish for a reduction of 25 to 75% of the cardiovascular morbidity.
During the first Climate-Health Summit of the WHO in August 2014, many countries and organisations signed an agreement on reforestation and engaged themselves to plant 100 million trees. Everywhere, the implementation of the different “Clean Air Acts” induced a reduction in cardiovascular mortality.
The argument from the health system meets the climatic changes theory: less flammable fossils, more trees. Montreal engaged itself to increase its green areas from 20 to 25%. Revolution? Toronto is at 27%, Halifax is at 40% and the Greater Vancouver Area is at 42%.
Hospitals, health care and good citizen examples
Hospitals and health centers are important advocates in our communities, not only for healthcare, but also as good examples of corporate citizens.
More and more, there is a preoccupation with the environmental impact buildings have on our health. The green hospital is emerging.
The environmental health meets the objectives of the climate experts. In the global mandate of the Quebec provincial government, we notice the preoccupations that all the ministries and organisations include a strategy to reduce the Greenhouse effect and pollutants in their development and choose to find green solutions in all regards.
The 3Rs (reduce, reuse, recycle) are highly diffused in the health system, conscious that hospitals alone release 2% of the Greenhouse effects of the country.
Health institutions are beginning to include themselves in this environmental hygiene approach.
National Tree Day began at the Cité de Laval in Québec in September 2008 and now takes place in many cities, from Sherbrooke to Val d’Or, from Three-Rivers to Lanaudière.
This day is the occasion to emphasize the links between the environment and health, to diffuse recent environmental health knowledge and to mention the positive initiatives or our institutions.
Individual actions reinforce collective behaviour
Notwithstanding the political and temporal upheavals, the hospital administrators and the doctors must integrate this new knowledge in their decision to join the efforts of the governments and the enterprises. Each one of our individual actions reinforces our collective actions.
Think globally, act locally.