Asthma afflicts appoximately 25 million, or one in 12, people in the U.S., and the numbers are growing every year, according to the Centers for Disease Control and Prevention.
Every day in this country, 44,000 people have an asthma attack and nine of them die, states the website of the Asthma and Allergy Foundation of America. Roughly 36,000 children miss school, 27,000 adults miss work and 4,700 people visit the emergency room on any given day due to asthma.
Given these statistics, asthma diagnosis and management should be a priority for any primary care practice. But family physicians, pediatricians and general internists typically don’t know enough about asthma, says Massoud Mahmoudi, DO, PhD, the president of the American Osteopathic College of Allergy and Immunology.
For osteopathic family physicians, many of whom practice in rural communities without allergists or pulmonologists nearby, being able to accurately diagnose and effectively address asthma is crucial, Dr. Mahmoudi says. But asthma’s complexity makes this a tall order.
“Most of the literature suggests that asthma, in general, is under-diagnosed, although physicians over-diagnose exercise-induced asthma in the obese,” says allergist and immunologist Timothy J. Craig, DO, a professor of medicine and pediatrics at the Penn State College of Medicine in Hershey, Pa.
Just as problematic, physicians under-assess the intensity of asthma in patients previously diagnosed with the condition. “Doctors tend to just ask patients, ‘How is your asthma?’ ” Dr. Craig says. “And patients, if they have fewer than two emergency department visits a year, may say, ‘Oh, I’m fine.’
“Physicians don’t ask the right questions and, as a result, underestimate the severity of their patients’ asthma, so many patients go untreated or minimally treated.”
Improving asthma diagnosis
Characterized by chronic inflammation of the airways, asthma is a complicated disease that cannot be cured but can be controlled. When triggered by an allergen, environmental irritant, exercise or physiological change, an asthmatic individual’s bronchial tubes become more swollen than usual and the muscles around the airways can tighten, making it difficult for air to move in and out of the lungs. This causes such symptoms as wheezing, coughing, shortness of breath and chest tightness.
Although the disease is under-diagnosed overall, many physicians make an initial diagnosis of asthma too readily, Dr. Mahmoudi says. “If a patient is wheezing and coughing, many primary care doctors will assume that he or she has asthma. The doctor will simply give that patient a steroid inhaler and send him or her out the door,” he notes.
Wheezing, however, is a symptom of many conditions and diseases, some less severe and others more life-threatening than asthma, including bronchitis, acid reflux, vocal cord dysfunction, chronic obstructive pulmonary disease, pneumonia, pulmonary embolism, lung cancer and heart failure.
In addition to a detailed medical history, a social history probing the patient’s home environment, and a thorough physical examination, proper diagnosis of asthma requires using a spirometer to assess a patient’s lung function, says Dr. Mahmoudi, the editor and a co-author of Allergy & Asthma: Practical Diagnosis and Management. Spirometers cost between $2,000 and $3,000 and can be shared by several physicians in a practice. But primary care physicians seldom use them, according to Dr. Mahmoudi.
“You rarely see family doctors do spirometry, but they should,” he insists. Among other pulmonary function characteristics, spirometers measure forced expiratory volume per second and forced vital capacity. The ratio of these two values before and after a patient uses a short-acting beta agonist provides an indication of whether he or she has asthma. If the pulmonary function test shows nearly full reversibility of the airflow obstruction, this suggests that the patient has asthma rather than COPD or another obstructive pulmonary disease.
One drawback, however, is that spirometry can’t be used with children younger than 6 because they aren’t able to follow the instructions, Dr. Mahmoudi says. But children often develop allergy-induced asthma, the most common type, before age 5. Physicians need to look at a child’s symptoms and family medical history carefully and order an allergy test before making a suspected diagnosis of asthma.
This preliminary diagnosis will need to be confirmed with sprirometry when the child can follow directions for the pulmonary function test, Dr. Mahmoudi says.
Another shortcoming of spirometry is that it isn’t easy to use a spirometer without significant practice, Dr. Craig says. In doctors’ offices, the task is normally delegated to nurses. If they use a spirometer only occasionally, nurses in primary care practices may not develop their spirometry skills, and physicians, in turn, may not interpret the results correctly, he notes.
“Unless you’re doing pulmonary function tests regularly and reading them regularly, spirometry probably isn’t a useful tool,” Dr. Craig says. “You have to maintain your skills and evaluate your nurses to make sure they are doing the test correctly.”
Consequently, Dr. Craig recommends that, when feasible, primary care physicians refer suspected asthma sufferers to allergists or pulmonologists for lung function and other testing. If patients have asthma, such specialists will also be better able to gauge the severity of the disease using spirometry and the latest clinical guidelines for asthma issued by the National Heart, Lung, and Blood Institute (NHLBI).
A relatively new method of measuring lung function, impulse oscillometry (IOS) is simpler to perform than spirometry and requires minimal assistance from patients, so it can be used to diagnose asthma in young children, according to the National Institute of Allergy and Infectious Diseases. But an IOS machine costs roughly $50,000.
“An IOS device is easy to operate, and it can be used on little kids because the test is based on regular breathing—they don’t have to follow directions for a forced vital capacity,” Dr. Craig says. “However, very few physicians have IOS machines because they are so expensive. Most pulmonologists don’t even have them.”
Without wide availability of easy-to-use, discerning diagnostic tools, many primary care physicians simply treat what they suspect are asthma symptoms and erroneously view response to treatment as evidence of the disease, Dr. Mahmoudi says. This approach can have adverse consequences, he notes, because more serious diseases may go undetected, while patients with less-severe respiratory issues are unnecessarily subjected to medications that have side effects and lose effectiveness with repeated use.
Children who are wheezing because of a viral respiratory infection, for example, may feel better after taking oral corticosteroids, the medication most often given to younger pediatric asthma patients. “If children respond well to oral steroids and stop wheezing, many doctors think that confirms their diagnosis of asthma, but it doesn’t,” Dr. Mahmoudi says.
Long-term use of corticosteroids can reduce a child’s growth rate while causing such unpleasant side effects as hoarseness, a sore throat and thrush, a yeast infection of the mouth. For children who are truly asthmatic, the benefits of corticosteroids may outweigh the risks, but that is often not true for those who are misdiagnosed, according to Dr. Mahmoudi.
Rescuers versus controllers
Two general types of medication are used in treating patients for asthma: rescuers and controllers. Rescue medications, such as albuterol and other short-acting beta agonists, which can be inhaled or taken orally, provide quick relief during an asthma attack. In contrast, control medications—such as inhaled or oral steroids or drugs combining steroids with long-acting beta agonists—are designed for long-term daily use to prevent asthma symptoms from recurring.
“Oftentimes, patients have this backwards,” Dr. Mahmoudi says. “They use rescuer medication all the time. And when they have an asthma attack, they use controller medication.”
With frequent use, short-acting bronchodilators may lose their effectiveness—a phenomenon known as tachyphylaxis. “Many asthma deaths occur because patients keep using albuterol,” Dr. Mahmoudi says. “Before you know it, they are using it so many times a day that it doesn’t do anything, so they die when they have an asthma attack.”
Primary care physicians need to make sure that they understand the difference between rescuer and controller medication and educate their asthma patients accordingly, Dr. Mahmoudi says.
“Sometimes physicians don’t appropriately educate patients to distinguish between their rescuer and controller medications. But even with proper education, patients often get confused,” Dr. Craig observes. “The problem is that patients feel a lot better when they use albuterol. But when they use an inhaled steroid or any of the other maintenance therapies on a regular basis, they don’t get the same lift.
“As a result, they may stop using their maintenance medication.”
The best way to ensure compliance is for the physician and patient together to develop a written “asthma action plan” that spells out the daily treatment regimen and when to use the rescuer medication. The plan should explain how to handle worsening asthma or asthma attacks and when to call the doctor or go to the emergency room.
As part of their action plan, patients with moderate to severe asthma may benefit from using a peak flow meter at home. This inexpensive handheld device measures patients’ ability to push air out of their lungs. A decrease in peak flow alerts patients that their asthma is getting worse—often before they notice any symptoms, explains the American Lung Association.
Dr. Craig asks only a subset of his asthma patients to use a peak flow meter—those whose asthma is so severe that they become habituated to their illness and need an external sign that their symptoms are worsening. “Otherwise these patients don’t even realize when they are really sick,” he says. “By measuring their peak flow, hopefully they will notice changes in their breathing before they get too sick.”
Rule of twos
To ensure that asthma is well-controlled in patients previously diagnosed with the disease, physicians should ask them a series of questions known as the “rule of twos,” Dr. Craig says.
If the answer to any of the following questions is yes, patients may need a long-term controller if they aren’t already using one, a stepped-up dosage of their current controller or a stronger medication:
- Do you use your quick-relief inhaler more than twice a week?
- Do you awaken at night with asthma more than twice a month?
- Do you have daytime symptoms more than twice a week?
- Do you have asthma attacks more than twice a year, or are there any limitations on your ability to exercise or on your quality of life?
The rule of twos is the most helpful recommendation in the NHLBI asthma guidelines, Dr. Craig notes. Another useful guideline directs physicians to prescribe the lowest clinically effective dose of medication for the patient’s particular level of severity, stepping up treatment only incrementally if symptoms worsen.
Even though asthma’s severity is frequently underestimated, some physicians overtreat patients for the disease, Dr. Craig says. “There are physicians who put every asthma patient on the highest dose of Advair twice a day,” Dr. Craig points out. “They don’t even think about the severity of a patient’s asthma or whether it’s well-controlled.
“There is some risk in using long-acting beta agonists. If you don’t need them, you shouldn’t be using them. And if a patient can be well-controlled on a low-dose inhaled steroid, why would you want to use a high dose?”
In adults, the cumulative effects of using high-dose inhaled steroids for a long time can include osteoporosis, cataracts, glaucoma, Cushing syndrome and mood swings. “We really don’t know the consequences of high-dose inhaled steroids in kids,” Dr. Craig adds. “That’s because all of the safety studies involving children have only investigated the effects of low- and medium-dose inhaled steroids.”
Asthma strikes African-Americans disproportionately. In 2011, blacks were 20% more likely to have asthma than non-Hispanic whites. Between 2003 and 2007, African-American children had a death rate from asthma that was seven times that of white children, according to the federal Office of Minority Health. The asthma rate was also high in most Hispanic populations.
Dr. Craig believes that such health disparities are primarily socioeconomic in nature. In the Bronx, he says, 20% of children are estimated to have asthma. In low-income neighborhoods, mouse and cockroach allergens abound, and mold is ubiquitous.
For most inner-city children and adults with asthma, the disease is not well-controlled. “The main reason people who live in poverty don’t get better is that they can’t afford their medications,” Dr. Craig explains.
Low-income individuals also are accustomed to seeking care primarily in emergency departments. “They are used to getting care in EDs, and they don’t get follow-up care,” he says.
Dr. Craig believes that the Affordable Care Act will prove to be beneficial for economically disadvantaged asthma sufferers because “it allows people to receive health care who couldn’t receive it in the past.”
How often should asthma patients see a physician? The NHBLI guidelines suggest every three months. “I don’t know if that’s necessary,” says Dr. Craig. “With patients who are very dependable and take good care of themselves, I think seeing them on a six-month basis is adequate. But people with poorly controlled asthma probably should see a physician once a month.”