Dynamic hyperinflation during the 6-min walk test in severely asthmatic subjects

Effects of Asthma on the Performance of Activities of Daily Living: A Retrospective Study

The study aim was to identify the most problematic self--reported activities of daily living (ADLs). In a retrospective study, 1935 problematic ADLs were reported by 538 clients with 95% experiencing two or more problematic ADLs. Problematic ADLs were assessed by occupational therapists using the Canadian Occupational Performance Measure with walking (67%), household activities (41%), and climbing the stairs (41%) identified as the most prevalent problematic ADLs. Significant but weak associations were found between clinical determinants (e.g. physical, psychosocial) and problematic ADLs. The wide variety of problematic ADLs and the absence of a strong association with clinical determinants emphasizes the need for using individualized interview-based performance measures in clients with asthma.

Using the 6-min walk test to assess the clinical response to mepolizumab and conventional therapy in severe eosinophilic asthma

Background

Severe asthma limits exercise to avoid respiratory symptoms. The objective of the present study was to investigate the role of the 6-min walk test (6MWT) in severe asthma.

Methods

Consecutive patients with severe eosinophilic asthma were enrolled. A 6MWT was performed before and after 12 months. Inhaled therapy dose, oral corticosteroids dose, pulmonary function tests, eosinophil blood count, fractional exhaled nitric oxide (FeNO), Asthma Control Test (ACT) score and responses to the Asthma Quality of Life Questionnaire (AQLQ) were also recorded.

Results

Of the 22 patients enrolled, 13 were treated with mepolizumab 100 mg every 4 weeks in addition to conventional therapy and nine with conventional therapy only. The majority of the patients were treated with high-dose inhaled corticosteroids/long-acting β-agonists/long-acting muscarinic receptor antagonists, while approximately half were on continuous oral corticosteroids. After 12 months, the mepolizumab group only showed a significant improvement in pulmonary function tests (percentage forced expiratory volume in 1 s and percentage forced expiratory flow at 25-75% forced vital capacity (FEF25-75%), both p<0.001; percentage forced vital capacity, p<0.01) and clinical laboratory parameters (eosinophil count, FeNO measured at a flow rate of 50 mL·s-1, ACT and AQLQ, p<0.001). No significant changes in the proportion of patients using continuous oral corticosteroids and high-dose inhaled corticosteroids/long-acting β-agonists/long-acting muscarinic receptor antagonists were observed in either group (p>0.05). By paired comparisons, statistically significant improvements of the mean 6-min walk distance (6MWD) were observed in the mepolizumab (p<0.001) and conventional therapy (p<0.01) groups, while no improvement was seen in dyspnoea Borg scale, heart rate, percentage oxygen saturation or systolic and diastolic blood pressure. 6MWD showed significant direct correlations with ACT (r=0.5998, p<0.001), AQLQ (r=0.3978, p=0.009) and FEF25-75% (r=0.3589, p=0.017).

Conclusions

The 6MWT could complement severe asthma assessment and be relevant in evaluating the objective response to treatment, including biological therapies like mepolizumab.

Does the severity of asthma affect exercise capacity and daily physical activity?

OBJECTIVE

Exercise capacity, daily physical activity, and psychological profile are crucial aspects in the management of asthmatic patients. Whether these features are expressed in a different way in mild-moderate (MMA) and severe asthma (SA) is unknown.

METHODS

In this observational cross-sectional study, patients matching the American Thoracic Society/European Respiratory Society (ATS/ERS) definition for SA underwent incremental cardiopulmonary exercise testing (CPET), full lung function testing, and an evaluation of daily step count and physical activity. Questionnaires on quality of life, general fatigue, and presence of anxiety and depression traits (Hospital Anxiety and Depression Scale - HADS) were administered. Patients were compared with a cohort of age- and gender-matched MMA patients.

RESULTS

We enrolled 16 SA, 17 MMA patients, and 16 healthy subjects. Compared to MMA, SA subjects showed a median (interquartile range) reduced peak oxygen consumption during CPET (20.4 (17.2-23.3) vs. 25.6 (18.5-30.3) ml/min/kg; p = 0.019), a reduced resting lung function (FEV1% of predicted 77 (67-84) vs. 96 (84-100); p < 0.001) and a pronounced anxiety trait at HADS (9.5 (3-11.7) vs. 4.0 (2.0-7.5); p = 0.023). In addition, SA patients showed a significantly higher reduction in inspiratory capacity from rest to peak (310 (160-520) vs. 110 (-65-325) ml; p = 0.031). We found no significant differences in mean daily step count or quality of life.

CONCLUSIONS

Compared to MMA, SA patients present a reduced exercise capacity and a more pronounced anxiety trait, but not worse daily physical activity or quality of life. These aspects should be considered in the clinical management and research development of SA.

The potential role of SP-D as an early biomarker of severity of asthma

Surfactant decreases the surface tension of peripheral airways and modulates the immunological responses of the lung. The alterations of surfactant due to the airway inflammation suggest a role in the pathogenesis of asthma. We aim to test the hypothesis that serum levels of SP-A (Surfactant Protein A) and SP-D (Surfactant Protein-D) are altered in patients with mild asthma compared to healthy controls and those alterations are related to functional abnormalities of peripheral airways, which are an early marker of progression of asthma. In this pilot study, we recruited 20 mild asthmatics and 10 healthy controls. We measured serum SP-A and SP-D and all subjects underwent clinical, lung functional and biological assessments. Serum SP-D was significantly higher in asthmatics compared to healthy controls (mean (SD) values: 7.9(4.65) vs 3.31(1.71) ng ml^-1,p-value: 0.008). In the asthmatic group, serum SP-D was significantly correlated to CalvNO (alveolar NO concentration) (R-squared: 0.26;p-value: 0.014). These preliminary findings suggest that serum SP-D could be used as a lung-specific biomarker of small airways damage thus predicting the progression to the most severe forms of asthma.

The Hidden Burden of Severe Asthma: From Patient Perspective to New Opportunities for Clinicians

Severe asthma is an important topic in respiratory diseases, due to its high impact on morbidity and mortality as well as on health-care resources. The many challenges that still exist in the management of the most difficult-to-treat forms of the disease, and the acknowledgement of the existence of unexplored areas in the pathophysiological mechanisms and the therapeutic targets represent an opportunity to gather experts in the field with the immediate goals to summarize current understanding about the natural history of severe asthma and to identify gaps in knowledge and research opportunities, with the aim to contribute to improved medical care and health outcomes. This article is a consensus document from the “International Course on Severe Asthma” that took place in Palermo, Italy, on May 10–11, 2019. Emerging topics in severe asthma were addressed and discussed among experts, with special focus on patient’s needs and research opportunities, with the aim to highlight the unanswered questions in the diagnostic process and therapeutic approach.

Dynamic hyperinflation impairs daily life activity in asthma

INTRODUCTION

Dynamic hyperinflation has been documented in asthma, yet its impact on overall health and daily life activities is unclear. We assessed the prevalence of dynamic hyperinflation in moderate to severe asthma and its relationship with the scores of a set of specific and general respiratory health questionnaires.

METHODS

77 nonsmoking asthma patients (Global Initiative for Asthma steps 4-5) were recruited consecutively and completed five questionnaires: Asthma Control Questionnaire, Clinical COPD (chronic obstructive pulmonary disease) Questionnaire, St George's Respiratory Questionnaire, London Chest Activity of Daily Living scale (LCADL) and Shortness of Breath with Daily Activities (SOBDA). Dynamic hyperinflation was defined as ≥10% reduction in inspiratory capacity induced by standardised metronome-paced tachypnoea. Associations between level of dynamic hyperinflation and questionnaire scores were assessed and adjusted for asthma severity.

RESULTS

81% (95% CI 71.7-89.4%) of patients showed dynamic hyperinflation. Higher levels of dynamic hyperinflation were related to poorer scores on all questionnaires (r=0.228-0.385, p<0.05). After adjustment for asthma severity, dynamic hyperinflation remained associated with poorer scores on LCADL (p=0.027) and SOBDA (p=0.031).

CONCLUSION

Dynamic hyperinflation is associated with poorer overall health and impaired daily life activities, independent of asthma severity. Because of its major impact on everyday life activities, dynamic hyperinflation is an important target for treatment in asthma.

Effects of weight loss on dynamic hyperinflation in obese women asthmatics

Obese adults with asthma are more likely to develop dynamic hyperinflation (DH) and expiratory flow limitation (EFL) than nonobese asthmatics, and weight-loss seems to improve the breathing mechanics during exercise. However, studies evaluating the effect of weight loss on DH in obese adults with asthma have not been performed. We sought to evaluate the effect of a weight loss program on DH in obese adults with asthma. Forty-two asthma patients were enrolled in a weight loss program (diet, psychological support, and exercise) and were subsequently divided into two groups according to the percentage of weight loss: a ≥5% group ( n = 19) and a <5% group ( n = 23). Before and after the intervention, DH and EFL (constant load exercise), health-related quality of life (HRQoL), asthma control, quadriceps muscle strength and endurance, body composition, and lung function were assessed. Both groups exhibited a decrease of ≥10% in inspiratory capacity (DH) before intervention, and only the ≥5% group showed clinical improvement in DH compared with the <5% group postintervention (-9.1 ± 14.5% vs. -12.5 ± 13.5%, respectively). In addition, the ≥5% group displayed a significant delay in the onset of both DH and EFL and a clinically significant improvement in HRQoL and asthma control. Furthermore, a correlation was observed between reduced waist circumference and increased inspiratory capacity ( r = -0.45, P = 0.05) in the ≥5% group. In conclusion, a weight-loss of ≥5% of the body weight improves DH, which is associated with waist circumference in obese adults with asthma. In addition, the group with greater weight-loss showed a delayed onset of DH and EFL during exercise and improved asthma clinical control and HRQoL. NEW & NOTEWORTHY This is the first study to evaluate dynamic hyperinflation (DH) after a weight loss program in obese patients with asthma. Our results demonstrate that moderate weight loss can improve DH in obese patients with asthma that is associated with a decrease in abdominal fat. Moreover, a minimum of 5% in weight loss delays the onset of DH and expiratory flow limitation besides inducing a clinical improvement in asthma quality of life and clinical control.