As per the Central Pollution Control Board, the overall air quality in Delhi continues to be in the ‘severe’ category for the fifth straight day. On November 6, the air quality in the National Capital was recorded at 488 as per data issued by the System of Air Quality Forecasting and Research (SAFAR-India). Apart from Delhi, other parts of NCR like Noida, Faridabad, Ghaziabad and Gurgaon, as well as cities across the country like Mumbai and others have also been witnessing a spike in pollution cases.  

According to doctors, for any healthy person, a recommended AQI should be less than 50, but these days the AQI has spiked beyond 400 in NCR, which could prove fatal for those suffering from lung-related diseases and even poses a risk of lung cancer. Stroke seems another risk factor. Dr Vipul Gupta, director, Neurointervention, Artemis-Agrim Institute of Neurosciences, Gurugram, shares, “Air pollution continues to be a significant concern to public health and a tough problem confronted by society. Despite the fact that the adverse effects of air pollution have been long known, there is less awareness that the majority of the morbidity and mortality caused by it is due to the effects on the cardiovascular system. Evidence from epidemiological studies has demonstrated a strong association between air pollution and cardiovascular diseases including stroke. Of particular concern are findings that the strength of this association is stronger in low- and middle-income countries where air pollution is projected to rise as a result of rapid industrialisation.”

According to Dr Gupta, more than 90% of the global stroke burden is linked to modifiable risk factors, of which air (Ambient and Household) pollution tops the list. It is important to prevent casualties from stroke due to air pollution. So how to identify a stroke risk? Dr Gupta shares, “Recognisable symptoms will occur prior to getting a stroke attack which is often known as a mini-stroke. The symptoms are only persistent for a minute but indicate a major onset of stroke within 2 days. Timely intervention can help preserve 2 million neurons per minute as inhaled compounds like PM and CO lead to clot formation and block the blood flow to the brain.” 

 

So how does pollution impact health? Dr Gupta explains, “The particles inhaled into the lungs are ingested by cells called macrophages, which leads to local inflammatory response within the lung and ultimately spreads to blood vessels in the body. The reaction leads to change in blood vessel functioning as well as lipid levels in the circulation.  The inflammation (reaction) caused by pollution particles lead to alteration of blood circulation including heart rate regulation. There is extensive evidence demonstrating reductions in various parameters of heart rate variability (HRV) after exposure to PM2.5. Several animal studies have shown that exposure to urban PM and diesel exhaust particles increases the incidence or susceptibility to heart rate irregularities (arrhythmia) which can lead to clot formation in the heart, predisposing to stroke.”