Air Pollution and Strokes

In a series of studies called the 'Global Burden of Disease,' which began in 1990 in collaboration with the World Bank and the World Health Organization, the number of deaths and disabilities caused by diseases in various countries is calculated. These countries need local data for health planning and preventive measures. The main goal of these studies is to calculate the 'burden of death' and 'burden of disability' due to diseases. The latest research in this series, published in the prestigious medical journal 'The Lancet,' examines the relationship between air pollution and environmental pollution with strokes in countries. This research, conducted using medical data from 188 countries from 1990 to 2013, is considered the first global assessment of the impact of air pollution on strokes. More than 300 causes of death and disease and 70 risk factors were examined in this study, with air pollution being one of the more widespread issues globally. According to this research, it can be said that if there were no air pollution or if we had very low levels of air pollution, we could prevent 14% of stroke-related deaths in Iran. Dr. Mohammad Hossein Forouzanfar, one of the managers of this global research in the risk factor calculation section, states: 'Our calculation shows that globally there are more than six and a half million deaths due to strokes. Iran's share is around 28,000 stroke-related deaths in 2013, which we set as the reference year. Of these deaths, 15,000 occurred among men and 13,000 among women. We calculated that, given the level of pollution faced by our country's population, about 14% of stroke deaths can be attributed to air pollution. In other words, based on this research, it can be said that if there were no air pollution or if we had very low levels of air pollution, we could prevent 14% of stroke-related deaths in Iran.' Strokes can occur due to reasons such as the blockage or rupture of one of the blood vessels supplying the brain. According to the president of the Iranian Neurology Association, 150,000 to 160,000 people experience strokes annually in the country, and about 20,000 of these individuals lose their lives. Dr. Forouzanfar, a manager of this global research, refers to the conditions of strokes in Iran in light of the increase in dust storms in the country: 'The average air pollution level in Iran in 1990 was about 28 micrograms per cubic meter, and this amount has increased by 10%. Based on satellite maps and the map we calculated for the entire country, there are two main pollution centers. One center is in the central and eastern part of the country, mainly due to desert conditions, but in urban areas, the red zones and high levels of migrants are seen in Tehran, Arak, and Khuzestan province. We can consider Khuzestan province, where a significant amount of this pollution is due to dust storms. A portion of the pollution in Iran is due to pollution from desert areas in the southern provinces and central regions. Studies have shown that any reduction in dust storms, regardless of their source, can decrease the risk of strokes. We are positioned on a risk curve concerning various levels of air pollution, where even small successes, such as 5% or even 10% reductions, can have a significant impact on public health. This is the minimum effect it has.' The likelihood of strokes in Iran is becoming more serious each year. According to studies in this area, the age of strokes in Iran has decreased by 10 years. Last year, a campaign titled 'Let’s Hear the Stroke' was launched in Iran, aimed at familiarizing people with the signs of this disease. Officials state that 15% of those who suffer a stroke die, but 70% of survivors are disabled and unable to work. Therefore, a specialized committee for managing stroke treatment was established in 2015 at the Ministry of Health, and 64 hospitals across the country are working to reduce the damage caused by strokes. Mohammad Hossein Forouzanfar, the manager of the risk factor calculation section of this research in the U.S., says that all these probabilities and simple conditions for stroke can be reduced with simple solutions such as reducing air pollution: 'Air pollution has decreased in most countries, especially developed countries, over the past 10 to 20 years. This means we are facing something that can be addressed with public actions and controlling pollution sources, such as reducing fossil fuel use. Stroke-related deaths have decreased globally, and they have also decreased in Iran. However, the number of strokes has increased, and nothing can replace initial preventive actions to reduce the risk of stroke, which is through reducing risk factors like air pollution. Air pollution is one of the risk factors for strokes.' Experts say that strokes can occur at any age. The reality is that the risk of stroke is more serious in individuals with risk factors; having a history of diabetes, high blood pressure, high cholesterol, atherosclerosis, physical inactivity, and smoking are among these risk factors: 'Air pollution is something that can be reduced with actions. The level of safety that we think is completely accessible is around eight micrograms per cubic meter, which is something achievable and not theoretical. The most significant pathway through which increased air pollution causes death is cardiovascular diseases, and nearly three times this number of deaths is due to heart diseases caused by air pollution. Air pollution has other effects, such as chronic respiratory diseases, lung cancer, and respiratory infections. Short-term effects can have a significant burden, and studies within the country have also shown that increased air pollution on days with high pollution levels leads to increased eye, respiratory, and even psychological effects like fatigue.' The likelihood of heart strokes in individuals aged 60 to 80, who have more fragile blood vessels, increases. However, pollution and air density can accelerate these conditions and worsen the situation. Although it is said that in recent years, the Iranian population is at a lower risk of death from strokes, this is not due to the control of risk factors but may be attributed to increased access to healthcare and educational services. Nevertheless, the prevalence of the disease in Iran has increased over a specific period. Our study showed that since 2011, stroke-related deaths have decreased, but risk factors have not changed significantly. Except for smoking, which has slightly decreased, some risk factors like air pollution have increased. However, in every age group, when we look at the probability of death, it has decreased by nearly 40%. People in Iran in 2013 were at a lower risk of death from strokes. But this is not because risk factors have been controlled. Researchers say that Iran has managed to some extent to prevent stroke-related deaths, but these patients are at risk of disability and loss of quality of life, placing a heavy financial burden on families and the government. This situation can be addressed with primary preventive actions, including reducing air pollution and combating the phenomenon of dust storms in the country.