- Health

Effect of smog on cardiovascular health

As experts like Best Internal Medicine Specialist in Islamabad tell, the cardiovascular effects of inhaled smog particles, are responsible for substantial mortality and morbidity. Research shows that exposure to exhaust fumes, among other forms of pollutants, has both acute and chronic effects on the cardiovascular system. 

Governments and health organizations arounds the world are getting increasingly worried about the worsening air quality index (AQI) and its impact on the people. The adverse effects of smog on the pulmonary and respiratory system is well understood. However, recent data shows that the cardiovascular system is also impacted due to poor air quality. These adverse health effects are exacerbated in individuals who already suffer from cardio-pulmonary diseases, as seen in the elderly. 

How does smog effect cardiovascular system?

Poor air quality index means lower oxygen levels in the air, with high particulate matter (PM) and ambient air pollutants (AAP). These pollutants contribute to artery blockages, permanent heart damage and infarction. This death of the heart tissue is due to oxidative stress and blockage of the blood vessels supplying oxygen to the muscle of the heart. Contributing factors involve pulmonary inflammation secondary to smog. 

Records show when the concentration of particulate matter rises in the air, hospital admissions due to heart attacks, heart diseases and congestive heart failure increases exponentially. 

On the other hand, when the air levels of ambient air pollutants like nitrogen oxides rise, there is increase in both hospital admissions and mortality index due to: fatal arrythmias. 

Apart from the increase in death rate due to short-term spikes, death due to long-term exposure are also seen. In cities with high nitrogen oxide and other pollutants, the death rate due to cardiovascular diseases in four times higher. 

What does research suggest?

Studies show a positive correlation between high risk in particulate matter and prevalence of cardiovascular diseases. In one research, there was an increase in heart disorders from 0.5 percent to 1.5 percent for every 5-6 microgram per cubic meter, rise in particulate matter. Cardiovascular deaths due to this rise, showed a 69 percent increase, in comparison to the 28 percent rise in deaths due to respiratory diseases. This effect is acknowledged by the American Heart Association and the Environmental Protection Agency (EPA). 

In another study based in Boston, emergency room admissions reported a rise in cases of acute myocardial infarction (heart attack) with the rise in nitrogen oxide in the air index. This Intermountain Heart Collaborative Study found an increase of 4.5 percent in coronary artery disease with every 10 microgram per cubic meter, rise in particulate matter. 

A similar research in Europe and the United States, correlating air pollution and cardiovascular disease found increase in death due to cardiopulmonary causes secondary to rise in particular matter. This study, analyzing 50 million people in 20 largest cities, showed that the death rate increased by 0.68 percent and was associated with a rise of 10 microgram per cubic meter the day before death. 

Data from other numerous studies find that air pollution causes significant rise in blood pressure as well. In fact, people with no history of hypertension find a rise in diastolic blood pressure readings after two hours exposure to ozone and particulate matter. Even higher rises are attributed to carbon monoxide levels. 

As mentioned before, these adverse effects are amplified in the elderly and those who have pre-existing cardiovascular diseases. Such risk factors should be discussed with the primary healthcare provider like Best Internal Medicine Specialist in Karachi and measures to mitigate the effect of air pollution should be taken. These could include: limiting time in the outdoors especially during the peak hours, using an air purifier and adhering to medication.