Diagnosis and Treatment of Asthma in Elderly Patients
article first appeared in the respiratory therapists' monthly magazine,
AARC Times. While it contains some medical terminology, those adults
who are being diagnosed with asthma later in life may find this information
The diagnosis and treatment of asthma are often focused on younger patients. However, over the last several years there has been a rise in asthma diagnosis in the elderly population. More than 1 million American adults older than age 65 carry a diagnosis of asthma, affecting approximately 5–7% of adults in this age range. However, the number of seniors with this condition is no doubt much higher since asthma is one of the most under-diagnosed diseases in the United States, especially among older adults. According to the National Hospital Discharge Survey, hospitalizations for asthma are approximately 27.2 per 10,000 in the 65+ age group. This is second only to the 0–17 age group, with approximately 28.4 per 10,000.1 In addition, according to the Centers for Disease Control and Prevention (CDC), there were approximately 5.8 asthma deaths per 100,000 in the 65+ age group from the years 2001–2003. The National Health Interview Survey reports that current asthma prevalence in elderly adults is highest among Puerto Ricans.2
Asthma diagnosis difficult in the
A history of atopic disease in this age group is strongly suggestive of asthma. Allergic rhinitis, sinusitis, and nasal polyps may all accompany asthma. Different allergic triggers may be more common among seniors than younger adults. For example, it has been estimated that elderly asthmatic patients living in the inner city have been sensitized to cockroach antigen and that patients with cockroach sensitization may have an increased risk for asthma morbidity.4 Respiratory tract infections are a major precipitating factor of asthma in elderly patients as well. These infections can be more prolonged and resistant to treatment in older patients. The reasons are still being studied, but researchers suggest reduced immune responses and previous lung damage may play a role in these differences. Furthermore, current evidence suggests elderly patients may have reduced symptom perception and may present later in their disease course, leading to delays in treatment and more severe exacerbations.5
According to the CDC, asthma deaths in the elderly population account for more than 50% of asthma fatalities annually.6 In a study by Lee et al, elderly asthmatics had significantly more near-fatal episodes as well.7 Factors thought to contribute to such risk include:
At diagnosis, elderly asthmatics tend to present with longstanding symptoms or they may have “late-onset” disease, typically over 65 years of age. Patients with longstanding asthma have more atopic disease and less reversible airflow obstruction consistent with “airway remodeling” (structural damage to lung tissue and airways).8 Those who present with “late-onset” asthma tend to have less allergic-mediated disease, more preserved pulmonary function, and more substantial responses to bronchodilators.
Spirometry has been used as a “gold standard” in diagnosis and monitoring treatment in asthma. However, it is estimated that less than 25% of elderly patients who present with cough and shortness of breath will be tested, often because of compromised access to care, patient underrating of symptoms, and confounding medical illnesses.9 Furthermore, in approximately 8% of elderly asthmatics, airway obstruction is absent at time of testing; and further testing, which may include methacholine challenge testing or even cardiopulmonary exercise stress testing, may be indicated to facilitate a diagnosis. In subjects thought to be at risk, spirometry should be obtained first. In those without evidence of obstruction but who remain at risk, methacholine challenge testing can be used to further refine the probability that asthma is present. However, this test is not 100% sensitive or specific for asthma; and as a measure of airway hyperresponsiveness, it may not be predictably accurate in the elderly population.10 Other features, such as measuring the carbon monoxide diffusing capacity of the lung (DLCO), may help distinguish between COPD and asthma. In the setting of airflow obstruction, a reduced DLCO value may suggest emphysema while a normal or increased value is more supportive of asthma.
Asthma pharmacotherapy entails additional risk for adverse drug interactions or effects in elderly patients. Several classes of medications used more frequently in older people may trigger or worsen asthma. Some of these include aspirin and other anti-inflamma tory medications used to treat arthritis and other pain syndromes. Beta-blocking agents for hypertension and glaucoma are all known to potentially cause or worsen asthma attacks. Ace inhibitors for hypertension and diabetes may worsen or mimic asthma-associated cough. Symptoms suggestive of these adverse drug effects may be as subtle as new cough, decreased exercise tolerance, wheezing, or shortness of breath. Beta-2 agonists may aggravate ischemic heart disease and can also cause tachyarrhythmias. Steroids may accelerate osteoporosis, decrease serum potassium levels, and worsen congestive heart failure. Methylxanthines, such as aminophylline and theophylline, if used, can cause rapid heart rates, headache, nausea, and seizures. Close monitoring of blood levels is warranted if prescribing these medications.
Invite patients to participate in their own care
Enright P. The diagnosis of asthma in older patients. Exp Lung Res 2005; 1 Suppl:15-21.
Health-Cares.net web site. What’s the treatment for asthma in the elderly? Available at http://respiratory-lung.health-cares.net/elderly-asthma-treatment.php Accessed Dec. 28, 2006
Morris MJ. Difficulties with diagnosing asthma in the elderly. Chest 1999; 116(3):591-593.
About the Authors
About the Authors