Bronchial asthma is a common condition; it is estimated that roughly one per cent of the world population have bronchial asthma. Its incidence is a little more in boys than in girls; in adult life, this difference disappears. Incidence is high or even slightly more, in the upper income groups than in the lower.
Influence of Heredity
Asthma occurs more often in person who have a family history of the disease. The greater the degree of inheritance, the greater the likelihood of the offspring becoming sensitive. Furthermore, when both the parents are affected, the disease in the children appears earlier, and often before puberty.
One inherits as allergic predisposition rather than a specific allergic disease; children of a parent suffering from hay fever may develop asthma or eczema and not necessarily hay fever.
Influence of Infection
It has been observed that, many a time, after a throat infection, a child becomes breathless, has wheezy sound in the chest and presents a clinical picture of asthma. When the infection subsides, the chest returns to normal condition. Such symptoms may recur afterwards.
Childhood infections, such as measles, pneumonia, whooping cough or infection in the tonsils and adenoids can set up symptoms of asthma in an already predisposed child.
At times, infection makes an allergy-prone individual to start getting symptoms of allergy. A pre-existing sensitivity to a specific allergen may become manifest in the presence of infection. Once such a sensitivity is activated, it may continue even after the infection is over.
Patients of allergic rhinitis and asthma have excessive secretions from the nose and the lungs. These secretions are excellent medium for the growth of micro or organisms, so that rhinitis and asthma patients are more liable to chest infections.
Thus we see that allergy and infection set up a vicious circle in which each aggravates the other, and the infected asthma patient develops chronic bronchitis and emphysema more often than one with asthma alone. Treatment of both the conditions side by side- infection with proper antibiotics, and allergy with appropriate anti-allergic measures-can ensure early recovery.
Influence of Emotional States
While a young girl was working in the kitchen, the gas burst and she died from the burns she suffered. On that very day, her mother developed asthma which continued for ten days and then gradually abated.
There is a history of allergy in her family; her father and one of her brothers have eczema. This lady now invariably gets asthma attacks when she hears news related, or in any way similar to the circumstances of her first attack.
Any excessive emotional reaction is known to, sometimes, precipitate an attack of asthma in a person who is already predisposed to it. It has been observed that some asthmatic children when sent to hostels show an improvement in their symptoms. This, among other things, may be due to the child being rid of the emotional problems that surround him at home.
Influence of Climate
Generally speaking, a dry climate is better suited to an asthmatic than a humid one; he feels better away from a sea coast than near it.
Rainy weather, with its increased humidity, is troublesome to some asthmatics. But patients who are allergic to pollens feel better after the rain, as all the pollens present in the air get washed down. The same thing happens in an industrial area having air pollution because most of the pollutants get washed down.
A dry climate, however, is no panacea for the asthmatic, as there are many other factors that come into the picture.
Asthma patients allergic to some pollens develop their symptoms or find them to be aggravated in the early hours of the morning. This is because the flowers of some plants open and discharge their pollens with the first rays of sunlight.
Winds : Some patients experience difficulty when a wind from a particular direction starts blowing. It is probable that the wind picks up pollens in its path, to which the patient is sensitive and when the patient is exposed to it, he gets the symptoms of asthma.
Barometric Pressure : A sudden drop in barometric pressure, as happens immediately before a thunderstorm, is unsuitable to an asthma patient. Some asthmatics and sinusitis patients are so sensitive to this fall in barometric pressure that they can foretell the coming of storms on the basis of the symptoms that they get even when there are no obvious indications.
Altitude : It has been observed that many asthma patients do not develop symptoms when they go to hill stations. It seems that the improvement in the symptoms of these patients is not so much due to the high altitude, as it is to
1. Changed environment.
2. Changed plants and pollens.
3. Lessened dust, in particular house dust.
Mites, the allergenic factor in house dust, grow slowly at the lower temperatures of the hill stations.
Influence of Occupation
Some occupations are particularly hazardous for people with an allergic background or for those who have some manifestations of allergy already in them, as for example asthma. Farmers, poultry-men, dairy workers and bakers are exposed to large amounts of fungus spores. Gardeners, farmers and farm labourers are exposed to a large number of pollens; upholsterers and mattress renovators are exposed to large quantities of house dust; flour- mill workers and carpenters are exposed to various kinds of dusts; beauticians, barbers or furriers are exposed to excessive amounts of animal dander.
For a patient who already has asthma, such occupations may lead to an aggravation of the symptoms. But if a patient has an allergic background and no manifestations of allergy yet, exposure to excessive amounts of pollens, dusts and molds because of a particular occupation, may lead to the appearance of symptoms of allergy.
Asthma, however, rarely develops after the initial contact with an offending agent. Usually there is a sensitization period of months or even years before any allergic manifestation appears. One asthma patient who came under my observation had symptoms only when he was in his shop; as soon as he came back home, he had no symptoms. He dealt in footwear and was found to be sensitive to leather dust. As soon as somebody cleaned the floor of his shop, he developed symptoms of asthma.
There are certain occupations which cause allergic manifestations not only in the workers but also in people who live in the surrounding area. Such occupations are a public health problem.
Same is the case around every factory area—Chimney’s fumes are contagious and the chimney’s are of short length, so these contagious fumes are mixed in lower level of air, causing asthma in different age groups.