Asthma – Inflammation of the Respiratory Tract: Symptoms, Causes, Treatment and Study

Natural environments reduce the number of asthma attacks, experts say

Asthma is a disorder caused by inflammation in the airways (called bronchi) that lead to the lungs. This inflammation causes the airways to constrict, which prevents air from flowing freely to the lungs, making breathing difficult.

Every year many people with asthma require treatment in the emergency departments with a portion that requires hospitalization.

Children under the age of 18 represent a large part of emergency department visits and hospitalizations due to asthma exacerbations.

The magnitude of the impacts of asthma on children is illustrated by the fact that asthma is responsible for more hospitalizations in children than any other chronic disease. In addition, asthma causes children and adolescents to miss school days and causes parents to miss days at work.

As expected, asthma also explains more school absences than any other chronic illness.

It has long been known that trees help keep our air clean, and new research now shows that they could have a dramatic effect on the number of people entering the hospital with problems related to asthma.

Experts call for more trees to be formed on city streets, after the largest study has analyzed the impact of urban vegetation on respiratory conditions, discovering that planting vegetation could help counteract the dangerous effects of traffic fumes .

Common symptoms of asthma

  • Cough especially at night and when exercising.
  • Difficulty breathing.
  • Sensation of pressure in the chest.
  • Wheezing: a screeching or whistling sound.


  • Allergens such as dust, animal skins, cockroaches, mold, tree pollens, herbs or flowers.
  • Irritants can be some things nearby, such as cigarette smoke, pollution, dust from the workplace or routine household decoration products such as lacquer, perfume, etc.
  • Medications are also a cause like aspirin or other nonsteroidal anti-inflammatory drugs.
  • Food and drinks that contain sulfites.
  • Viral infections of the upper respiratory tract like cold.
  • Physical activity as exercise or running.


There is no cure for asthma, but with proper guidance and following the instructions and treatment protocols of the doctor. Asthmatic patients can lead a normal life. They only have to deal with the triggers that most affect them.

The initial treatment plan depends on the severity and the ongoing treatment will depend on how well the action plan controls the symptoms and prevents the attacks.

There are two types of medications available to treat asthma. First is the long-term control and the second is quick relief medications. Long-term control medications can help reduce airway inflammation, while quick-relief medications decrease the symptoms of sudden onset asthma.

Here is a list of some controller medications:

  • Inhaled corticosteroids such as fluticasone, budesonide, mometasone, ciclesonide, flunisolide, beclomethasone.
  • Asthma inhalers contain an inhaled corticosteroid along with a long-acting beta-agonist that are useful for opening the airways. Long-acting beta agonists should never be prescribed without asthma inhalers.

The study

Researchers at the University of Exeter’s Faculty of Medicine (UK) studied the impact of urban vegetation on the respiratory condition and claim that the results suggest that planting trees could help reduce the dangerous effects of traffic fumes.

However, large areas of gardens with lawns or green areas could worsen asthma, the findings suggest, because grass pollen fuses with pollution, triggering a condition known as “gray fever.”

It is known that pollution exacerbates asthma, but researchers found that even in the most polluted areas, a high density of trees led to lower asthma admissions than in less contaminated neighborhoods with fewer trees.

The findings are true, although tree pollen can often trigger asthma, suggesting that the effect of absorbing pollution is greater than the allergenic impact, particularly when contamination is high.

The researchers concluded that, in general, trees did “much more good than harm”, with every 300 additional trees per square kilometer associated with about 50 fewer emergency asthma cases per 100,000 residents over a 15-year period.

“Green space and gardens were associated with reductions in hospitalization for asthma at lower levels of pollutants, but not in the most polluted urban areas. With the trees it was the other way around, “said study leader Dr. Ian Alcock.

“Grass pollen may become more allergenic when combined with air pollutants, so the benefits of green space diminish as pollution increases.

“On the contrary, trees can effectively remove air pollutants, and this may explain why they seem to be most beneficial when concentrations are high.”

The study, published in the journal Environmental International, analyzed more than 650,000 serious asthma attacks for 15 years in England.

By comparing 26,000 urban neighborhoods, researchers found a link between areas heavily populated by trees and lower rates of emergency hospital visits for asthma.

While tree coverage was associated with the benefit of asthma sufferers in highly contaminated areas, the findings suggest that those who suffer in areas of low contamination may not benefit as much.

This is because in areas of low pollution, the foliage can retain the accumulations of irritating pollutants that would otherwise have been dispersed by the wind.

Met Office’s lead climate scientist and study co-author, Dr. Rachel McInnes, said that research showing different effects according to the type of vegetation was important for public health and urban planning policies.

“We also know that the interaction between pollen and air pollution, and the effect on health and asthma is very complex and this study confirms that more research is needed in this area,” he said.

The study also noted that asthma was strongly related to socioeconomic deprivation, and that researchers controlled that factor.