What are the reasons for poorly controlled bronchial asthma in a patient?

Reasons for Poorly Controlled Bronchial Asthma

Poorly controlled asthma results from a complex interplay of patient-related factors (primarily medication non-adherence and incorrect inhaler technique), physician-related factors (underestimation of symptom severity and inadequate prescribing), environmental triggers, and comorbid conditions that must be systematically identified and addressed before escalating therapy. 1

Patient-Related Factors

Medication Non-Adherence

• Poor adherence to prescribed controller medications is one of the most common reasons for inadequate asthma control, with 40-50% of patients underusing their prescribed medications due to concerns about side effects, particularly with long-term inhaled corticosteroid therapy 1, 2
• At least 40% of patients report underusing prescribed medications in terms of either frequency or dosing, and when higher inhaled corticosteroid doses are prescribed, at least 50% refuse to fully adhere because of concerns about adverse effects 1
• Fewer than one-third of patients with asthma, including those with severe persistent disease, report regular use of preventive asthma medication 1

Incorrect Inhaler Technique

• Critical mistakes with inhaler technique occur in 17% of patients and are independently associated with poor asthma control (OR: 3.03) 3
• Patients often do not use their inhalers with proper technique, preventing them from gaining the benefit of these therapies or achieving control 1
• Significantly fewer critical mistakes occur among certain dry powder inhaler users (10.3% versus 18.4% for other devices) 3

Patient Perception and Expectations

• Many patients overestimate their level of disease control, often tolerating substantial asthma symptoms and having low expectations about the degree of control that is possible 1
• Between 39-70% of respondents to the Asthma Insights and Reality surveys reported their asthma was well controlled or completely controlled even though they were experiencing moderate symptoms 1
• Patients may assume that a certain level of symptoms or activity limitation is an inevitable consequence of having asthma 1

Self-Management Deficits

• Additional patient-related factors include self-management abilities, ability to remember doses, access to prescriptions, and costs of medication 1

Physician-Related Factors

Underestimation of Disease Severity

• Physicians have a tendency to underestimate the prevalence of asthma symptoms and to overestimate the degree to which their patients' asthma is controlled, therefore they may not always prescribe adequate controller medication therapy 1
• Both patients and physicians tend to underestimate the severity of symptoms or overestimate the patient's level of disease control 1

Inadequate Prescribing

• Inadequate prescription according to guidelines occurs in 35.9% of patients and is strongly associated with poor asthma control (OR: 3.65) 3
• Physicians may have an inadequate understanding of disease etiology or may not communicate well with patients, making it difficult to establish a pharmacotherapeutic regimen that the patient is willing and able to follow 1

Environmental and Trigger Factors

Allergen and Occupational Exposures

• Ongoing occupational or allergen exposures should be identified and eliminated when possible, as these are exacerbating factors that prevent asthma control 1, 2
• Occupational history should be considered for adults with uncontrolled asthma, especially if symptoms improve on weekends and holidays 1
• Unrecognized allergens, occupational sensitizers, dietary additives, and environmental factors need to be identified and avoided or treated 4

Smoking Status

• Smoking status is an additional patient-related factor affecting asthma control 1

Viral Respiratory Infections

• Perhaps the environmental factor that contributes most to the development, persistence, and severity of asthma is viral respiratory infection 1
• Although influenza vaccination is recommended for patients with asthma because of their risk of influenza-associated complications, vaccination should not be expected to reduce the frequency or severity of exacerbations during influenza season 1

Medication-Related Factors

Drug-Induced Exacerbations

• Asthma can be exacerbated by certain drugs, such as nonsteroidal anti-inflammatory drugs and β-blockers 1
• Aspirin-sensitive asthma is relatively common in Eastern Europe and Japan and is frequently associated with a genetic sequence variation 1
• Antagonism of the β-adrenoreceptor, even with β-selective medications, should be avoided for patients with asthma 1

Comorbid Conditions

Untreated Comorbidities

• Asthma may be difficult to control in the presence of untreated gastroesophageal reflux disease or other comorbid conditions 1, 2
• Comorbidities that might contribute to poor asthma control require treatment in their own right 1
• Upper airway disease, rhinosinusitis, or other systemic diseases need to be identified and treated 2, 4

Alternative Diagnoses

• It is critical to make a diagnosis of asthma and to exclude other airway diseases, particularly chronic obstructive pulmonary disease (COPD) and vocal cord dysfunction ("pseudo-asthma") 4
• Numerous overlapping disorders can present with symptoms that may be indistinguishable from asthma 1

Disease-Specific Factors

Corticosteroid Resistance

• Some patients are completely resistant to corticosteroids, but more patients are relatively resistant and require relatively high doses of corticosteroids to control their symptoms (steroid-dependent) 4
• Corticosteroid resistance is a major problem in patients with severe asthma, and several molecular mechanisms have been described 5

Severe Asthma Phenotypes

• A small but important group of patients has severe asthma per se that is refractory to routine treatments 6
• Some patients have instability of their asthma, with resistant nocturnal asthma, premenstrual exacerbations, or chaotic and unpredictable instability (brittle asthma) 4
• Some patients develop progressive loss of lung function, as in patients with COPD 4

Systematic Approach to Evaluation

Before stepping up therapy, the National Asthma Education and Prevention Program recommends systematically reviewing:

• Adherence to medication 1, 2
• Inhaler technique 1
• Environmental control and modifiable risk factors 1
• Comorbid conditions 1

The presence of multiple risk factors compounds the problem: patients with a higher number of risk factors have a higher probability of having badly controlled asthma 3. In the EFIMERA study, 76.8% showed low adherence, 35.9% had inadequate prescription, and 17% had critical mistakes with inhaler technique 3.