Asthma is a disease that extensively contracts our breathing ways in lungs (bronchus). This happens as a result of some stimulants.
This contraction can recover by medicine or sometimes by itself. There are many reasons of this contraction:
Muscles around bronchus can be stretched
Bronchus can excessively secrete sticky mucus
There can be Oedema on bronchus wall
Veins in bronchus can enlarge and new veins can be formed.
Cells that lay down bronchus can fall.
Cell walls can become thick as a result of connective tissue increase.
Various inflamed cells can come together on bronchus walls.
The most important change in asthmatic’s bronchus is the inflammations on which eosinefil cells are dominate. This allergic inflammation continuously exists even at recovering periods of the illness. Bronchi of asthmatics show excessive sensitivity to both allergic and non-allergic stimulants (cold weather, training, smoke, smell…). We call this as bronchus hyperactivity. That’s why a sharp smell and cigarette smoke cause cough, growling and shortness of breathe on asthmatics. In the light of this information we can say asthma has three main characteristics:
Extensively contraction on bronchus.
Allergic inflammation on bronchus.
Excessive bronchus sensitivity.
SORTS OF ASTHMA
There are several sorts of asthma and it is classified in various forms. However there are two main asthma type: -Allergic asthma, Non-allergic asthma.
Main characteristic of allergic asthma is there is one or more allergens (house mites, pets, pollens, aspergillus etc…) to which patients are sensitive. This sensitivity can be shown by allergic skin tests or IgE blood evaluating. Allergic asthma’s first symptoms are seen at childhood. Other allergic illnesses such as allergic catarrh, eczema, medicine allergy, food allergy etc. are very frequently seen on patient and his family. Allergic asthma gives good answer to medicine treatment and immunotherapy.
There is not a definite allergen to which patient is sensitive; skin tests are negative and IgE limits in blood are normal. The reasons of asthma crisis of these patients are viral infections (catarrh, influenza etc.) cold weather, dirty weather, cigarette smoke, medicine (aspirin, analgesic, rheumatism medicines…), food additives, dye, polish, varnish, perfume, stress etc… On many patients illness symptoms occur after 30 years of age. Other asthma and other allergic illnesses are seen on these people’s families as same frequently as normal people. Progress of non-allergic asthma is more chronic than allergic asthma; crises are heavier and resistant to treatment. Immunotherapy is not applied to these patients.
HOW DOES ASTHMA EMERGE?
Both environmental and hereditary factors play a role on asthma. In order a person to be asthmatic, first of all he has to have genetic predisposition. This genetic predisposition is under the control of many factors. Thus, a person who has predisposition to asthma, one day starts to show asthma symptoms under effect of environmental factors (dirty air, cigarette, viral infections, dense allergen contact…). According to researches, about %40 of people have predisposition to asthma genetically, but asthma emerges only on definite portion of these people.
WHAT ARE ENVIRONMENTAL FACTORS?
When people who genetically have predisposition to asthma are exposed to environmental factors below, asthma development risk starts to rise:
Having been excessively exposed to allergens (house dust, pets, aspergillus etc…) since the day borne
Mother’s smoking while pregnancy
Smoking in house since early years of childhood –
Viral respiration system infections (bronchiolit)
Unhealthy settling of houses (traffic, houses near factories and work-sites etc…)
Unsuitable house conditions (badly aired, dark and damp environments
Various materials added in food and beverage (sweeteners, materials giving smell and preventing decomposition)
Factors related to climate.
Although people who are not exposed to these environmental factors genetically have predisposition to asthma, it is possible that they do not show any symptom belonging to asthma during their lifetime. Environmental factors are mentioned in ‘Allergy’ section in detail.
IT IS NOT ENOUGH YOUR HOUSE IS AWAY FROM FAULT LINE
Recently it has been understood that some characteristics of house might be effective on asthma prevalence.
Storey of house: it has been shown that there are more mite allergens in basements and ground floors, and this facilitates sensitivity.
Number of rooms: asthma prevalence is higher in houses where one room is shared by many people. Here, it might be effective that being exposed to more allergens and viral infections.
Damp of house: it is known that kitchen and relative damps of houses have a big effectiveness on allergen amounts. In order to accept a house as damp, kitchen damp should be more than 7 g/kg and relative damp should be more than %45. Mites cannot survive under these values. In every house where more than 2 microgram of mite allergen exist in 1 gram of house dust, kitchen damp has been found more than 7 g/kg and relative damp has been found more than %45.
Ventilation of house: ventilation of house is an important factor for damp. Damp reduces in houses that are ventilated by mechanical ventilation. Good ventilation is defined as at least 0.5 air changes (ach) in an hour. There are less mite allergens in houses where ach is bigger than 0.5.
Carpets in houses: In houses having wall to wall carpet there are much more mite allergens than houses without carpet.
Pets: after mites, the most important allergen source in houses is pets. Especially cats are important among pets. Allergens emerge from cat’s skin or saliva. Diameter of these allergens is about a few microns and they can suspend in air for a long time. On carpet and cloth covered furniture there are many allergens. They can stick on walls of house and can be carried to other places by dresses. Recently researches shown that children who grew up with pets in the same house and children who grew up in a farm with farm animals are less likely have asthma.
Cleaning way of house: specially developed high technology cleaning devices reduce mite allergens in houses.
Heating way of house: In Germany a research has been done on more than 5000 school children. Relations between skin tests and heating and cooking ways in houses have been examined and autopsy and straw catarrh prevalence has been found meaningfully higher on children who live in houses heated by gas heater, petrol fire-place and central heating than children who live in houses heated by firewood and coal.