The Role of Comorbidities in Difficult-to-Control Asthma in Adults and Children

Assessment of asthma comorbidities, conditions that adversely affect the pathobiology of asthma or impair its response to therapies, is a fundamental step in the evaluation and management of patients with difficult-to-treat asthma. Identifying and effectively treating asthma comorbidities, such as obesity, obstructive sleep apnea, and chronic sinusitis with nasal polyps, may improve asthma control and reduce exacerbations. In addition, identifying comorbid T2 inflammatory conditions may help guide optimal selection of biologic therapies. Here, we describe common comorbid conditions found in adult and pediatric difficult-to-control asthma, discuss evidence for the association with asthma morbidity and treatment benefit, and provide information on how and when to assess comorbidities.

The Impact of Adherence and Health Literacy on Difficult-to-Control Asthma

Medication nonadherence and health literacy are key factors that influence the management of difficult-to-control asthma. Adherence, or the extent to which a patient follows a treatment plan, extends beyond asthma medication use and includes an appropriate inhaler technique. Assessment of adherence is critical before making a diagnosis of severe asthma and stepping up asthma therapy but is challenging in the clinical context. Health literacy, or the degree to which individuals can obtain, process, and understand health information and services needed to make health care decisions, is additionally important for asthma management and has been shown to impact medication adherence. Initiatives aiming to improve difficult-to-control asthma should address medication adherence and health literacy. Universal health literacy precautions are recommended while communicating with patients, in addition to the creation of low health literacy asthma action plans. To improve adherence, a comprehensive assessment of adherence should be conducted. Additional evidence-based interventions aiming to improve adherence focus on appropriate inhaler use, improved access to medications, the use of digital platforms, school-based asthma interventions, and the implementation of culturally tailored interventions. Data are limited regarding the use of these initiatives in patients with severe or difficult-to-control asthma.

Clinical Outcomes in People with Difficult-to-Control Asthma Using Electronic Monitoring to Support Medication Adherence

BACKGROUND

Nonadherence in difficult-to-control asthma can be identified using 7-day FeNO suppression testing where patients take additional fluticasone via Diskus with an Inhaler Compliance Assessment (INCA) acoustic monitoring device attached, and self-measure FeNO at home. However, this is inconvenient for patients attending a tertiary center and limited by FeNO meter availability. It is not known if this approach alters clinical outcomes.

OBJECTIVES

To examine patient acceptability and the effectiveness of replacing usual combination inhaled corticosteroid (ICS)/long-acting β₂-agonist (LABA) therapy with a fluticasone/salmeterol Diskus 500+INCA for 28 days as the initial intervention, compared with the 7-day FeNO suppression test, and to explore clinical outcomes after INCA monitoring.

METHODS

A service evaluation of FeNO suppression testing was undertaken in clinical practice.

RESULTS

Twenty-one of 23 subjects offered replacement of their usual ICS/LABA with fluticasone/salmeterol+INCA as the initial intervention accepted and completed 28 days of monitoring. Fourteen (66.6%) patients reduced their FeNO by >42% (FeNO suppressors), accompanied by improvements in forced expiratory volume in 1 second, Asthma Control Questionnaire, and blood eosinophils, similar to the 7-day test (n = 74). Twenty-two of 62 (35.5%) FeNO suppressors progressed to biological therapy, compared with 24 of 33 (72.7%) nonsuppressors (P = .0006). FeNO suppressors taking maintenance prednisolone (n = 13) who did not receive biological therapy reduced the median baseline dose from 10 to 3 mg, with further reductions limited by adrenal suppression.

CONCLUSION

Replacing existing inhaled therapy with fluticasone/salmeterol+INCA for 28 days is acceptable to the majority of people with difficult-to-control asthma and identifies prior medication nonadherence. INCA monitoring coupled with clinical support potentially improves patient adherence and asthma control, preventing unnecessary progression to biological therapy.

Comorbidities in Difficult-to-Control Asthma

BACKGROUND

Difficult-to-control asthma is associated with significant medical and financial burden. Comorbidities are known to contribute to uncontrolled asthma. Better insight into the prevalence, nature, and risk factors of comorbidities may optimize treatment strategies in patients with difficult-to-control asthma and decrease disease burden.

OBJECTIVES

The objectives of this study were to assess the prevalence, number, and type of comorbidities in difficult-to-control asthma compared with not-difficult-to-control asthma, and to investigate whether specific patient characteristics are associated with particular comorbidities.

METHODS

A total of 5,002 adult patients with a prescription for high-dose (>1,000 μg) fluticasone or oral corticosteroids, extracted from 65 Dutch pharmacy databases, were sent questionnaires about patient characteristics. Of the 2,312 patients who returned the questionnaires, 914 were diagnosed with difficult-to-control asthma. Diagnoses of comorbidities (gastroesophageal reflux, nasal polyps, cardiovascular disease, anxiety/depression, obesity, and diabetes) were based on treatment prescriptions or questionnaires. Associations were assessed using multivariable logistic regression analyses.

RESULTS

A total of 92% of patients with difficult-to-control asthma had ≥1 comorbidity. Patients with difficult-to-control asthma had more comorbidities (mean ± SD comorbidities 2.22 ± 1.27 vs 1.69 ± 1.32; P < .01), and a significantly higher prevalence of each comorbidity, compared with patients with not-difficult-to-control asthma, except for diabetes and nasal polyposis. Comorbidities were associated with specific patient characteristics, including older age, female gender, smoking history, and chronic prednisone use.

CONCLUSIONS

Almost all patients with difficult-to-control asthma have comorbidities, in particular asthmatic women of older age, former smokers, and asthmatics who are prednisone dependent. Recognition of these typical characteristics can help physicians in the diagnostic workup, so that adequate preventive measures can be taken.

Real life study of three years omalizumab in patients with difficult-to-control asthma

BACKGROUND

Even though there are multiple options for the treatment of asthma, there still exists a fair group of patients with difficult-to-control asthma. We describe for the first time the real-world effects of three-year omalizumab treatment on patients with difficult-to-control asthma, seen in a social security hospital in a Latin American country.

METHODS

Difficult-to-control asthmatic patients from the out-patient clinic of a regional hospital were recruited to receive a three-year omalizumab course. Efficacy parameters were asthma control test (ACT) score; FEV1; daily beclomethasone maintenance dose; and unplanned visits for asthma exacerbations (emergency room (ER), hospitalisations, intensive care).

RESULTS

52 patients were recruited, 47 completed the three-year treatment (42 female, 15-67 years, mean age 43.5). Comparing efficacy parameters of the year before omalizumab with the 3rd year of omalizumab: mean ACT improved from 12.4 to 20.5, mean FEV1 from 66.3% (standard deviation (SD) 19.1%) to 88.4% (SD 16.2%) of predicted, while mean beclomethasone dose reduced from 1750 to 766 mcg/day and there was a significant reduction in patients experiencing ER visits (from 95% to 19%, p<0.0001), hospitalisation (38% to 2%, p<0.0001) and intensive care (4% to 0, NS). Five patients discontinued omalizumab, two because of an adverse event (anaphylaxis, severe headache, both resolved without sequelae).

CONCLUSION

Omalizumab improved most clinical parameters of Mexican patients with difficult-to-control asthma. Especially the rates of ER visits and hospitalisation were significantly reduced, thus reducing costs. Omalizumab was generally well tolerated.

Prevalence and clinical profile of difficult-to-control severe asthma in children: results from pneumology and allergy hospital units in Spain

BACKGROUND

Severe asthma is often poorly controlled and its prevalence in Spanish children is unknown. The aim was to determine the prevalence of difficult-to-control severe asthma in children, the agreement of asthma control between physicians and Spanish Guidelines for Asthma Management (GEMA), and the health-related quality of life (HRQoL) for children and parents.

METHODS

Observational, cross-sectional, two-phase, multicentre study. In the first phase, all children who attended pneumology and allergy units during a three-month period were classified according to physicians' criteria as patients with: asthma, severe asthma, or difficult-to-control severe asthma. Patients aged 6-14 years with severe asthma (difficult-to-control or controlled) were included in the second phase.

RESULTS

12,376 asthmatic children were screened in the first phase. According to physicians' criteria, 8.8% (95% CI 8.3-9.3%) had severe asthma. Of these, 24.2% (95% CI, 21.7-26.8%) had difficult-to-control severe asthma. 207 patients with severe asthma (mean age 10.8 ± 2.3 years; 61.4% male; mean of 5.5 ± 3.4 years since asthma diagnosis) were included in the second phase. Compared to the patients with controlled asthma, children with difficult-to-control asthma had a higher number of exacerbations, emergency room or unscheduled primary care visits in the previous year (p<0.0001, all) and poor HRQoL (p<0.0001, both children and caregivers). 33.3% of patients with controlled asthma according to physicians' criteria were poorly controlled according to GEMA.

CONCLUSIONS

Around one in four asthmatic children with severe disease had difficult-to-control asthma, although one third was underestimated by physicians. Children with difficult-to-control severe asthma had a poor HRQoL that also affected their parents.