William Berger (Allergist and Immunologist) gives expert video advice on: What is "asthma"?; Can people die from asthma?; What causes asthma? and more...
What is "asthma"?
Asthma is a disease of the lungs. Asthma tends to affect the airways to the lungs we refer to as bronchi. Asthma causes swelling; tightening of the muscles around the airways of the lungs; inflammation, which includes what we refer to as edema, which is swelling of the interior; and mucus formation, that phlegm that people cough up. Asthma very often runs in families; affects people of all ages, but primarily children and young adults; and very often is associated with allergies. Asthma is one of the most common chronic diseases, and the most common chronic disease in children.
What is a "reactive airway disease"?
Reactive airway disease is the general term that's used for anybody who has tightness in their chest, coughing, or wheezing, in response to some type of trigger. Very often, that's infection, such as a cold or a virus. Very often, reactive airway disease can be triggered by allergens, pollens - things like trees, weed, grass pollens and also by exercise and other types of stimuli. However, reactive airway disease doesn't specifically describe a disease; it describes a condition, and that's why it's important that a proper diagnosis be made.
How many people have asthma in the US?
Asthma is one of the most common conditions that we find in the population. It affects about eight to ten percent of the population, and in children it may even be higher - over ten percent. Asthma is the most common chronic disease in children and the leading cause of school absenteeism. In other words, kids are missing school because of their asthma. In adults, it can affect the way they participate in activities. They miss a lot of work because of asthma, so asthma is a real public health problem.
Can people die from asthma?
Although rare, people can actually die from asthma. Asthma causes swelling. It causes constriction or tightening of the airways. It can cause a lot of mucous formation, and as a result, it can block the vital airways that allow us to breathe in and breathe out. When you can't get air, very often that will affect your ability to breathe, and as a result there will be greater and greater tightness of your chest due to asthma. Unfortunately, if it is not properly treated, (in many cases that means prevention of the reaction of a severe asthma attack) it can lead to death. Doctors are particularly concerned about patients who have been previously hospitalized, or those who have been incubated and put on respirators. Those patients are particularly at high risk from asthma. So, if you've had one of these high risk factors, or you're using your rescue medications too often, please see your doctor early because you are at the highest risk for having a severe episode and maybe even dying from your asthma attack.
What causes asthma?
Asthma is an inherited disease. Nobody really gives themselves asthma. It's inherited like the color of your hair, the color of your eyes, your blood type and your tissue type. People often say to me, "How can I prevent having asthma?" I usually say, "You just have to pick the right parents." Obviously, you can't decide who is going to have asthma and who is not going to have asthma. It is genetic and inherited. However, the severity of the asthma is very often associated with how quickly the diagnosis is made, how early in life the diagnosis is made and how soon proper treatment is instituted. You really can't prevent getting asthma, but you certainly can do a lot things to make sure your asthma doesn't get worse and out of control.
What kind of doctor do I see for asthma?
According to the guidelines that were developed by specialists and generalists in the area, when patients develop moderate to severe asthma, it's a very good idea for patients to seek the counsel of an asthma specialist. Asthma specialists are allergists or a pulmonologists, who will then do pulmonary function tests, may have to change the medications or add medications, and, in the case of an allergist, may very often find that the patient has severe allergies, and that by treating their allergies, they can significantly improve their asthma. The best advice that I can give you is: if your asthma is not properly diagnosed or if you're having symptoms that are not being addressed, you may want to seek the counsel of an asthma specialist, such as an allergist.
Can I develop asthma later in life?
Asthma can develop at any age. Certainly, we see the majority of asthma in children and young adults, but there is an adult-onset form of asthma, and very often, we see it more in women than we do in men. People who develop asthma over the age of 40 have less incidence of allergies, and unfortunately, their asthma, in many cases, is much more severe and requires much more intensive treatment. So, if you start coughing, wheezing, and getting short of breath, and you're in your 50s, it can be asthma; you need to see a doctor to get the right diagnosis.
Is asthma on the rise?
The incidence of asthma is certainly on the rise. In fact, the number of cases of asthma has actually doubled in the past twenty years, and it seems to correlate with a lot of things that we are noticing in our environment. There are more things like diesel fuel and more air pollution. The quality of air is not as good as it used to be. In addition, we notice that asthma also correlates with an increase in other allergic conditions. We are seeing much more hayfever or what we refer to as allergic rhinitis. We are seeing more sinus problems. We are seeing more food allergies. So in general, the incidence of allergies and asthma is increasing in the population and in many cases such as inner city areas like in South Bronx in New York, it has actually reached epidemic proportions.
What is "allergic asthma"?
There are many triggers to asthma and that is one of the important things to understand: just treating the symptom is not going to get rid of the problem. The most common trigger of asthma is allergies. Allergies affect the vast majority of patients with asthma and many allergic asthma patients also have other allergies such as allergies of the nose. Allergy is an over sensitivity of the immune system where our body overreacts to things that are just innocent substances. There is nothing particularly dangerous about cat dander, grass pollen or ragweed pollen, but when we have an immune system that overreacts and causes the release of chemicals that causes swelling, congestion and tightness, we experience an asthma attack. It is important to identify what those allergies are so that you can find the cause of the problem and get better after treatment is instituted.
What is "non-allergic asthma"?
Although allergies are very common triggers of asthma, there's a certain population of asthma patients that don't have allergies. That is seen more often in the older population - forty and older. It's important to know that you don't have to have allergies to have asthma, you can have non-allergic triggers. We know that infection is a very common cause, especially sinus infections. We know that reflux- what people think of as heartburn, can be a trigger of asthma. Exercise can be a trigger. So not just allergies, non-allergic factors can be important triggers in causing you to have your asthma symptoms.
What's the relationship between asthma and sinus problems?
Studies have shown that there's an association between sinus disease and lower airway disease, such as asthma, and that by treating a patient's sinuses, not only will their sinus symptoms get better, but that it will have a beneficial effect on their airways or their lungs that are seen in asthma. As a matter of fact, there's a thing called a sinobronchial reflex, and that reflex will very often show that when sinuses get inflamed, the lower airways get inflamed. There have actually been studies that suggest that just treating the sinuses alone will improve lung function.
What's the relationship between asthma and food allergies?
Just like in other allergic problems such as asthma and hay fever, we're seeing an increase in the incidence of food allergy. In children, milk, eggs and peanuts certainly can cause respiratory symptoms in addition to nasal symptoms, and we see when patients are taking these foods, and they're allergic to these foods, that it does cause an increase in their asthma. So, it's important that if you do think your child has a food allergy that it be tested for. In adults we tend to see that peanut, shellfish, flatfish and also some of the tree nuts can cause problems with asthma. Again, if you think you might have food allergy tell your doctor, have yourself tested, and in fact if you are allergic to those foods avoid them because they can cause exacerbation or reocurrence of your asthma symptoms.
What are "bronchi", "bronchioles" and "bronchial tubes"?
Very often patients are told that they have bronchial asthma, bronchitis or chronic bronchitis. Very often these are different descriptions of the same problem. Asthma is a disease that affects the bronchi. The bronchi are the airways that lead into the lung. When you look at the lung it looks rather like an upside down tree. We have a trunk, which is the trachea, then large branches of that tree, which are bronchi, and then breaking into smaller and smaller branches are the bronchioles. If we know that asthma is a disease of the bronchi that affects the airways, bronchial asthma is a redundant term, so any thing that affects your air ways has being bronchial. If there is inflammation we use the word 'itis', like when tonsils are inflamed we call it tonsillitis, or when eyes are inflamed you have conjunctivitis, so if you have itis of your bronchi they call it bronchitis .Very often they are really talking about asthma.
What are "alveoli"?
In order for the body to function we need to get oxygen into our bloodstream and we need to get rid of the carbon dioxide which is part of the waste products out of our bloodstream. The bronchi lead into small sacs called alveoli and it's at the level of the alveoli that we get the oxygen in from the air that we breathe in, then we get the carbon dioxide out by breathing out. It's important that our alveoli are functioning. Any disease that can affect the bronchi or the alveoli can interfere with that ability for us to get oxygen. Asthma, for example, when it narrows the airways, prevents oxygen from getting into the alveoli. The disease that we're most concerned about are patients who smoke and develop chronic bronchitis and emphysema, we refer to this as COPD, where there's actually destruction of these air sacs and those people are permanently in a situation where they are not getting enough oxygen in and not getting enough carbon dioxide out.
What is an "allergen"?
We commonly talk about allergies caused by an allergen. An allergen is another word for an antigen that causes an allergic reaction. It is usually a protein, and it can be something that is very commonly found in the environment – a pollen that's in the air, dander that's found on the surface of an animal, or even a dust mite, which is a microscopic insect inside the dust that's in our bedding. Any of these allergens can cause an allergic (or what we refer to as an immunologic) reaction where an allergen hooks on with an antibody that's located on the surface of the cells that line our airways, then cause that cell to burst and release chemicals. Those chemicals are the chemicals that cause the allergic reaction.
What is "bronchoconstriction"?
Bronchoconstriction is one of the characteristic features of asthma where we see tightening of the airways. And the reason bronchoconstriction occurs is because there are muscles, we refer to them as smooth muscles, that wrap around the airways. And when they tighten, it's kind of like squeezing a garden hose and you tighten it. As a result, less air can get through, kind of the way when you squeeze on a garden hose less water can get through. So, result, the sensation that you have is a tightening of your chest, a feeling of not being able to get air in and out. Bronchoconstriction can cause severe problems if it completely occludes or blocks the airway. It can mean that you're not getting oxygen at all and it can be a life threatening situation.
What's the difference between allergies and asthma?
Allergy is an overreaction of the immune system to things that are normally harmless. There's nothing very harmful about a pollen, a grass, a tree, or a weed, or a dust, or animal dander, but in people who are predisposed to allergies, they overreact. Now that overreaction can occur in different organs in the body. If it occurs in the nose, we call it hay fever or allergic rhinitis. If it occurs in the eyes we call it allergic conjunctivitis, and if it occurs in the lungs, we call it allergic asthma.Now asthma is an inflammatory disease of the lungs, and there are many triggers that can cause someone with asthma to have increased symptoms: exercise, cold air, viral infections, and allergies. So you can have asthma without having allergies, and you certainly can be allergic but it not infect your lungs. But in the majority of cases people with asthma do have allergies as one of their major triggers of their symptoms. And that's why it's important in every asthma patient to determine whether they do have allergies, because if they do and you treat them, you'll help benefit their asthma condition.
What will happen if my asthma is not treated?
Many patients say to me, "Well, I know I have asthma, how about if I just live with it? I mean, I don't really want to take medications. If I don't take medications can I just eat healthily and exercise and make it go away?" Well, I wish that were true but, in fact, untreated asthma in most cases tends to get worse. After it's been inflamed for a long period of time, normal tissue gets replaced by scar tissue and that tissue no longer acts properly in helping to exchange oxygen for carbon dioxide and as a result, after many, many years of what we refer to in medicine as remodelling (in other words, changing the architecture of the airways), you end up with a lot of scar tissue where healthy tissue used to exist and as a result you lose lung function.