What is Asthma?
Asthma is a chronic inflammatory disorder of the airways, caused by our reaction to allergens and irritants in the environment. The incidence of Americans with asthma has almost doubled since 1980 and is currently the leading cause of hospitalization for children under age 18.
When asthmatic airways come into contact with environmental triggers, they respond with a series of changes that lead to contraction of the smooth muscles that line the interior of the airways, swelling of the bronchial tissue, and the production of thick mucus. The result is difficulty in breathing, a feeling of chest tightness, and often coughing.
These episodes usually end by themselves or with medication, but they can also be severe and life-threatening. In the past, we viewed asthma as a completely reversible disease — that is we thought once acute symptoms ended, the lung function and airway architecture returned to normal. More recently, we have come to recognize that over time asthma can cause permanent damage to the health and function of the lungs.
These slow changes, which include permanent thickening of the airways, are known as remodeling. It is a process that changes asthma from an occasional reversible problem into a constant issue for pulmonary health. But with good care and an awareness of potential problems we can keep asthmatic airways clear and healthy.
Asthma usually begins in younger patients and can last a lifetime, but it can appear at any age. The symptoms of asthma are not always clearly apparent. For examples episodes of coughing that last for up to several hours and recur for weeks can actually be the first sign of asthma.
The Four Stages of Asthma
The issue of permanent lung changes from asthma is so important that we classify stages of asthma according to how often asthma attacks occur as well as the severity of the symptoms and measurement of lung function.
Stage I — Mild Intermittent Asthma
Symptoms occur less than twice a week during the day and last for several hours to several days. Nighttime symptoms occur less than twice a month. Between episodes, there are no problems and lung function is normal.
Stage 2 — Mild Persistent Asthma
Symptoms occur more than twice a week, but not more than once a day. In other words, you feel tightness and wheezing every day. Symptoms can be severe enough that you have to stop whatever you are doing to get breathing under control. Nighttime symptoms occur more than twice a month and lung function declines slightly.
It’s important to recognize that asthmatic attacks in mild persistent asthma can be severe and life-threatening. In fact, a study published in Pediatric Pulmonology found that 30% of asthma fatalities occurred in patients with mild, persistent asthma.
Stage 3 — Moderate Persistent Asthma
Symptoms are part of daily life and develop more than twice a week at night. Acute attacks occur more than twice a week and can last for days. Exacerbations are severe enough to interfere with daily activities, causing absence from school or work. Pulmonary lung functions can decline fairly sharply, reflecting the impact of persistent bronchial constriction.
Stage 4 — Severe Persistent Asthma
Symptoms of wheezing, chest tightness, and cough are constant during both day and night. It is difficult to participate in daily activities and quality of life suffers. Acute attacks are frequent and lung function has fallen to unhealthy levels. When people try to treat themselves with over-the-counter products, the relief can be short-lived and the results have been fatal.
Environmental Triggers
Asthmatics are particularly susceptible to certain factors in the environment. For example, plain cold air is a very well-known trigger for asthma. Pollen from plants pets, dust, air pollution, and household cleaning solutions all can provoke overresponsive airways. While more women than men are diagnosed with asthma, it may be more severe in men. A study from the Bellevue Hospital Asthma Clinic found that asthmatic men have lower lung function, more visits to the emergency room, and showed less of a response to medication intended to open blocked airways. Interestingly in children less than age five, asthma is diagnosed more frequently in boys than in girls.
Asthma tends to become worse at night, due to both physical and environmental issues. Sleep increases airway sensitivity, leading to bronco-constriction. One reason may be that the body continually releases an anti-inflammatory substance called cortisol. There is however a nighttime fall in cortisol levels, which in asthmatics may lead to increased airway inflammation.
The bedroom itself may be the unwitting source of many airway irritants. Bedrooms have a homes’ highest concentration of dust mites whose allergens are among the most frequent causes of asthma symptoms. These microscopic organisms burrow into carpets and bedding, hide under the bed and bury themselves in the folds of curtains. Eight hours of close exposure to high concentrations of dust mites during the night can be a constant trigger for nighttime symptoms.
The goal of asthma management is to control the symptoms, not to let asthma control your life.
