Poor perception of dyspnea following methacholine challenge test in patients with asthma

Perception of asthma control among asthmatics seen inChest Clinic at Tertiary Hospital, Addis Ababa, Ethiopia

BACKGROUND

Patient awareness of asthma severity is important for optimal asthma management. However, there is often a discrepancy between physician assessment of asthma control based on guidelines and patient discernment of control. We compared physician and patient perception of asthma control in a clinic population seen at a tertiary hospital in Addis Ababa, Ethiopia.

METHODS

In this cross-sectional study, 182 consecutive patients with a physician diagnosis of asthma seen in Chest Clinic at Tikur Anbessa Specialized Hospital (TASH) between July and December 2015 were studied. Demographics, asthma symptoms, medication use in the past month, and self-perception of asthma control in the past 7 days were obtained from the clinic records. Physician assessed asthma control was based on the GINA asthma symptom control assessment tool. Lung function was measured using a Diagnostic EasyOne Plus model 2001 SN spirometer. The institutional review board approved the study protocol.

RESULTS

Of the 182 subjects, 68.1% were female. The mean age was 52 ± 12 years, and the mean (SD) duration of asthma was 19.4 ± 12.7 years. Forty-four (24.2%) patients had physician determined well-controlled asthma and 138 (75.8%) patients had physician determined partly controlled/uncontrolled asthma. One hundred and fifty-one (83%) patients thought their asthma control was good. However, the degree of concordance between physician evaluation and patient perception of asthma control was low (kappa index = 0.09). On multivariate analysis, self-perceived poor asthma control was associated with any activity limitation due to asthma and inconsistent inhaled corticosteroid use.

CONCLUSION

In our study, the first of its kind in Ethiopia, a high percent of patients with physician determined well-controlled asthma has appropriate perception of their disease state. However, those patients with partly controlled/uncontrolled asthma had poor self-perception of their disease, emphasizing the need for further patient education. These conclusions may be especially useful in the care of asthmatics from other low-income countries.

Activity limitation and exertional dyspnea in adult asthmatic patients: What do we know?

Limitation of activity is the most cited symptom described by uncontrolled asthma patients. Assessment of activity limitation can be undertaken through several ways, more or less complex, subjective or objective. Yet little is known about the link between patients sensations and objective measurements. The present review reports the current knowledge regarding activity limitation and symptom perception (i.e., exertional dyspnea) in adult patients with asthma. This work is based on references indexed by PubMed, irrespective of the year of publication. Overall, patients with stable asthma do not have a more sedentary lifestyle than healthy subjects. However, during a cycle ergometric test, the maximal load is reduced when FEV1, FVC and muscle strengths are decreased. Additionally, during the six-minute walking test, mild asthma patients walk less than healthy subjects even if the minimal clinically important difference is not reached. The major complaint of asthma patients when exercising is dyspnea that is mainly related to the inspiratory effort and also to dynamic hyperinflation in some circumstances. Finally, the administration of bronchodilator does not improve the ventilatory pattern and the exercise capacity of asthma patients and little is known on its effect on exertional dyspnea. The present review allows to conclude that until now there is no gold standard test allowing the objective assessment of "activity limitation and exertional dyspnea" in asthma patients.

Repeated dyspnea score and percent FEV1 are modest predictors of hospitalization/relapse in patients with acute asthma exacerbation

OBJECTIVES

(1) Compare ideal cut-off points for DS and %FEV1 at 1 and 3 h to predict hospitalization/relapse in subjects with moderate to severe asthma exacerbation (2) Develop a multivariate regression model using DS, %FEV1, demographic, and clinical variables to predict hospitalization/relapse.

METHODS

Subjects with acute exacerbation of asthma (FEV1 <50% predicted following 30 min of standardized treatment: 5 mg nebulized albuterol; 0.5-1.5 mg nebulized ipratropium; and 50 mg oral prednisone) were eligible. All subjects had %FEV1 and DS obtained at baseline and hourly for 3 h. Using hospitalization/relapse as the outcome of interest; we compared the area under the receiveroperator curves (AUC) between the 1 and 3 h DS and %FEV1 measurements, and the AUC for the change in DS and %FEV1 between baseline and hour-3. We determined ideal cut-points for %FEV1 and DS to maximize sensitivity and specificity. Sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios (LR) were compared between %FEV1 and DS. We developed a multivariate regression model examining the association of specific demographic and clinical variables to hospitalization/relapse.

RESULTS

142 patients were included for analysis. The AUC was greatest for the 3-h DS (0.721), followed by the 3-h %FEV1 (0.669). Optimum cut-off values were a DS of 2, and an FEV1 of 42%. These were associated with a +LR for the composite outcome of 3.06 and 2.48 respectively. Logistic regression showed baseline DS, 3-h DS, change in DS, and oxygen use at hour 3 were all associated with the composite outcome.

CONCLUSIONS

The 3-h score for %FEV1 and DS performed better than scores at any other time point and better than either parameter over time. The 3-h DS had the greatest association with the composite outcome. Neither test was a strong enough predictor to be used solely for this purpose.

Airway disease: similarities and differences between asthma, COPD and bronchiectasis

Airway diseases are highly prevalent worldwide; however, the prevalence of these diseases is underestimated. Although these diseases present several common characteristics, they have different clinical outcomes. The differentiation between asthma, chronic obstructive pulmonary disease and bronchiectasis in the early stage of disease is extremely important for the adoption of appropriate therapeutic measures. However, because of the high prevalence of these diseases and the common pathophysiological pathways, some patients with different diseases may present with similar symptoms. The objective of this review is to highlight the similarities and differences between these diseases in terms of the risk factors, pathophysiology, symptoms, diagnosis and treatment.

A survey of recently published cardiovascular, hematological and pneumological original articles in the Brazilian scientific press

Recent original scientific contributions published in selected Brazilian periodicals and classifiable under cardiovascular and pulmonary subject categories cover a wide range of sub specialties, both clinical and experimental. Because they appear in journals with only recently enhanced visibility, we have decided to highlight a number of specific items appeared in four Brazilian journals, because we understand that this is an important subsidy to keep our readership adequately informed. These papers cover extensive sub-areas in both fields.