Air pollution can cause stroke: Neurologists

As pollution levels deteriorate in the National Capital Region, health experts have warned that continuous exposure to polluted air has the potential to cause a stroke among adults.

Alhough it was earlier believed that pollution only increased the risk of heart problems, it also possesses the capability to damage inner linings of veins and arteries.

"In the current scenario, the situation is getting worse. Many young patients in the 30-40 age group suffer from stroke. We get around 2-3 patients almost every month. The number of young stroke patients has almost doubled as compared to last few years. Studies suggest major risk factors include soaring air pollution," said Praveen Gupta, Director Neurology, Fortis Memorial Research Institute, Gurugram.

Research bodies estimate that the number of fragments of dead cells in the bloodstream increased with higher levels of pollution. Polluted environment promote stroke incidences more pervasively and at an earlier stage than previously thought.

Nearly 15 million people annually suffer a stroke worldwide, of which around six million die and five million are left with permanent disabilities such as loss of sight and speech, paralysis and confusion.

On the occasion of World Stroke Day, October 29, the experts emphasised that indoor air pollution caused by combustion of solid fuels is equally contributing to the stroke burden in the society.

On an average, the internal air pollution in Indian rural homes exceeds the World Health Organisation (WHO) norms by 20 times.

"Women inhaling the household fumes are at a 40 per cent higher risk of getting a stroke. The reason being the carbon monoxide and particulate matter from burning solid fuels tend to reduce the levels of HDl (high density lipoprotein). This in turn prevents the removal of lDl (low density lipoprotein) from the body leading to hardening of the arteries," said Jaideep Bansal, head neurologist at Saroj Super Speciality Hospital.

He added that the rise in the levels of lDl, or harmful fat, thereby raises the risk of a clot, blocking blood supply to the brain and causing stroke.

More than 90 per cent of the global stroke burden is linked to modifiable risk factors, of which internal air pollution tops the list. Other preventable factors include hypertension, a diet low in fresh fruits and whole grain, outdoor air pollution, high BMI and smoking.

The WHO states that 4.3 million people a year in India die from the exposure to household air pollution, which is among the highest in the world.

According to surveys, over 30 crore people in India use the traditional stoves or open fires to cook or heat their homes with solid fuels (coal, wood, charcoal, crop waste).

Poor ventilation and such inefficient practices, especially in rural India, mean the smoke and ambient air in households exceeds the acceptable levels of fine particles by at least 100-fold.

According to neurologists, recognisable symptoms, known often as a 'mini stroke' will occur prior to getting a stroke attack which is often known as a mini-stroke.

"Though it lasts only for a minute but certainly indicates the onset of a major stroke attack within 48-72 hours. Delay in treatment can lead to loss of 2 million neurons each minute. This happens due to the fact that the blood flow to certain part of the brain is blocked by the clot formed due to inhalation of compound like carbon monoxide and particulate matter," said Atul Prasad, Director and Senior Neurology Consultant at BlK Super Specialty Hospital.