Asthma in older adults is shown to have a significant impact on quality of life. Many times, asthma in the elderly coexists with conditions such as obesity, decreased immunity, and chronic obstructive pulmonary disease (COPD)—all of which are common among this population. As a result, asthma can often be complex and difficult to spot in the elderly.

Pathogenesis of Asthma in Older Adults

Poor respiratory muscle strength, decrease in elastic recoil, and greater rigidity of the chest wall are often all part of the natural aging process that may contribute to the onset of asthma.¹ Forced expiratory volume in one second (FEV₁) and forced vital capacity each decrease by between 25 and 30 mL every year after around the age of 20.² This is usually what contributes to reduced respiratory muscle strength and decrease in elastic recoil in older adults.

Aging also comes with 2 changes to the immune system that affect the pathology and treatment of asthma in older adults: immunosenescence and inflammaging.^1,2 These immune responses can make the elderly less responsive to vaccinations and cause higher infection rates that may either worsen asthma or lead to its onset.

Asthma is often triggered by environmental factors such as pollen, animal dander, dust, or smoke.¹ Avoiding triggers is one of the most effective ways elderly patients can manage their asthma. However, many older adults are unable to implement and/or adhere to lifestyle changes surrounding the control and avoidance of these triggers.²

Risk factors for late-onset asthma (LOA) include weight gain, obesity, smoking, rhinitis symptoms, chronic sinus symptoms, and new habitual snoring.¹ Viral infections are also common triggers for LOA, as is Chlamydia pneumoniae. Older adults who develop LOA are likely to have greater airway hyperinflation, partially reversible or irreversible airway obstruction, and a higher baseline FEV₁.¹

Challenges of Diagnosing Asthma in the Elderly

The symptoms of asthma in older adults are similar to those of other conditions and comorbidities commonly seen among this population. Cough is a prominent symptom of asthma in the elderly and is sometimes the only obvious symptom.²

Many times, asthma in the elderly is often confused with other diseases that are common among patients in this age group, such as COPD, congestive heart failure, and gastroesophageal reflux disease.¹Additionally, asthma often co-occurs with these other conditions, making it extremely difficult to determine which condition is contributing to poor health.

Older adults tend to assume that breathlessness is being caused by comorbidities such as obesity and cardiovascular disease.¹ Older adults are also less likely to report asthmatic symptoms due to denial, fear, cognitive impairment, depression, social isolation, and poor medical literacy. Those who do report symptoms of asthma are likely to also report poor general health, depression, and limitations surrounding performing normal daily activities.¹

At least 50% of older adults with asthma have recently been diagnosed with their condition.¹ The diagnosis process for asthma in this population is similar to that for younger patients. However, compared with their younger counterparts, older adults with asthma have greater morbidity and score lower on health-related quality of life assessments. Factors commonly found to influence asthma diagnosis in older adults include poor perception and reporting of asthmatic symptoms by the patient, the presence of extrapulmonary manifestations, and aging in the respiratory tract.¹

Essential Diagnostic Techniques

To properly diagnose asthma in older adults, clinicians must review medical history and perform a physical examination, along with a chest X-ray, electrocardiogram, and spirometry. A test of the diffusing capacity of lungs for carbon monoxide may help distinguish between asthma and COPD, but chest computed tomography may be helpful with identifying increased wall thickness and air trapping. Other tests that may be helpful with diagnosing asthma in the elderly include measurement of plasma brain natriuretic polypeptide, assessment of cardiac function using echocardiography, and the use of exhaled nitric oxide as a marker and measure of control.

Clinicians must keep in mind that physical exams in older adults with asthma may sometimes misguide the diagnosis. For instance, wheezing is a symptom of asthma and a number of other conditions, including COPD.² Also, considering that the ratio of FEV₁ over forced vital capacity decreases with age, clinicians must use age-adjusted values when diagnosing asthma. Clinicians may face challenges with bronchoprovocation in elderly patients who have cardiac comorbidities and low baseline lung function, as well as challenges in spirometry for those who are frail and who have poor cognition and coordination.²Spirometry requires patient engagement, and elderly patients tend to tire of spirometry relatively quickly.

The majority of older adults who develop asthma after the age of 65 experience their initial asthmatic symptoms before or at the same time as an upper respiratory tract infection.² Asthma in the elderly may also be triggered by medications like angiotensin-converting enzyme inhibitors and nonsteroidal anti-inflammatory drugs that are commonly used by this population. Therefore, it is essential for clinicians to perform a comprehensive review of all medications being used by older patients who may be demonstrating asthma symptoms.²

Treatment Considerations

Treatment of asthma in any age group must focus on symptom control and on preventing asthma from becoming worse. Asthma is typically treated using inhaled corticosteroids, but older adults often have altered airways and systemic inflammation that makes them less responsive to corticosteroid treatment.¹ In addition, older patients tend to have difficulty with managing complex medication regimens that include the use of inhaler devices and should be limited in the number of inhaler devices they use at any given time.

Asthma medications are shown to have limited efficacy when used by older adults. This population is highly likely to experience side effects such as cardiotoxicity when using beta-2 agonists and corticosteroids.¹ Older adults with asthma are also at high risk for drug interactions because the rate of comorbidities among this population is high and treatment for these conditions usually involve the use of one or more other medications.

Older adults with asthma may benefit most from a stepped treatment that involves the monitoring of adverse effects of bronchodilators and corticosteroids. This helps ensure therapeutic adherence and symptomatic control. Until further research can be done to identify asthma treatments that are most effective for the elderly population, clinicians who treat these individuals are advised to form multidisciplinary teams to ensure their patients are able to manage asthma and improve quality of life.

References

1. Gonzalez-Diaz SN, Villarreal-Gonzalez RV, De Lira-Quezada CE, Guzman-Avilan RI. Outcome measures to be considered on asthma in elderly. Curr Opin Allergy Clin Immunol. 2019;19(3):209-215
2. Hanania NA, King MJ, Braman SS, et al; on behalf of Asthma in the Elderly workshop participants.Asthma in the elderly: current understanding and future research needs—a report of a National Institute on Aging (NIA) workshop. J Allergy Clin Immunol. 2011;128(3):S4-24.

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