Effect of asthma severity on symptom perception in childhood asthma

Age and African-American race impact the validity and reliability of the asthma control test in persistent asthmatics

Background

The Asthma Control Test (ACT) is widely used to assess asthma control, yet the validity and reliability of the test have not been specifically evaluated in adolescents or African-Americans. We conducted a prospective psychometric study of the ACT in African-American (AA) and non-African-American (nAA) adolescents with persistent asthma, with emphasis on the clinical utility of the test for medical decision making.

Methods

Participants completed the ACT and performed spirometry. A physician conducted a guidelines-based assessment of asthma control, blinded to the ACT score. Study procedures were repeated 6–8 weeks later. The ACT-based asthma control assessment was compared to physician assessment.

Results

For baseline and follow-up visits, internal consistency, as measured using Cronbach’s alpha, was 0.80 and 0.81 in AA teens and 0.80 and 0.83 in nAA teens. Intraclass correlation coefficients were 0.59 and 0.76 in AA and nAA teens, respectively, with stable asthma control over time. Agreement between ACT and physician assessment was moderate in AA teens and fair in nAA teens. An ACT score of ≤19 showed reduced sensitivity for not well controlled asthma in both groups, while a score of ≤21 had the greatest area under the ROC curve. ACT scores were marginally responsive to change in control status.

Conclusions

Concerns for the ACT’s ability to detect uncontrolled asthma in adolescents emphasizes the need for a more comprehensive evaluation of asthma control in clinical settings. A higher threshold ACT score to define not well controlled asthma may be needed if the ACT is to be used for medical decision making.

Trial registration

ClinicalTrials.gov: NCT02671643, NCT02662413.

Electronic supplementary material

The online version of this article (10.1186/s12931-018-0858-0) contains supplementary material, which is available to authorized users.

Exercise-Induced Bronchospasm and Allergy

Sport is an essential part of childhood, with precious and acknowledged positive health effects but the impact of exercise-induced bronchoconstriction (EIB) significantly reduces participation in physical activity. It is important to recognize EIB, differentiating EIB with or without asthma if the transient narrowing of the airways after exercise is associated with asthmatic symptoms or not, in the way to select the most appropriate treatment among the many treatment options available today. Therapy is prescribed based on symptoms severity but diagnosis of EIB is established by changes in lung function provoked by exercise evaluating by direct and indirect tests. Sometimes, in younger children it is difficult to obtain the registration of difference between the preexercise forced expiratory volume in the first second (FEV1) value and the lowest FEV1 value recorded within 30 min after exercise, defined as the gold standard, but interrupter resistance, in association with spirometry, has been showed to be a valid alternative in preschool age. Atopy is the main risk factor, as demonstrated by epidemiologic data showing that among the estimated pediatric population with EIB up to 40% of them have allergic rhinitis and 30% of these patients may develop adult asthma, according with atopic march. Adopting the right treatment and prevention, selecting sports with no marked hyperventilation and excessive cooling of the airways, children with EIB can be able to take part in physical activity like all others.

Evaluating the Validity of an Automated Device for Asthma Monitoring for Adolescents: Correlational Design

BACKGROUND

Symptom monitoring is a cornerstone of asthma self-management. Conventional methods of symptom monitoring have fallen short in producing objective data and eliciting patients' consistent adherence, particularly in teen patients. We have recently developed an Automated Device for Asthma Monitoring (ADAM) using a consumer mobile device as a platform to facilitate continuous and objective symptom monitoring in adolescents in vivo.

OBJECTIVE

The objectives of the study were to evaluate the validity of the device using spirometer data, fractional exhaled nitric oxide (FeNO), existing measures of asthma symptoms/control and health care utilization data, and to examine the sensitivity and specificity of the device in discriminating asthma cases from nonasthma cases.

METHODS

A total of 84 teens (42 teens with a current asthma diagnosis; 42 without asthma) aged between 13 and 17 years participated in the study. All participants used ADAM for 7 consecutive days during which participants with asthma completed an asthma diary two times a day. ADAM recorded the frequency of coughing for 24 hours throughout the 7-day trial. Pearson correlation and multiple regression were used to examine the relationships between ADAM data and asthma control, quality of life, and health care utilization at the time of the 7-day trial and 3 months later. A receiver operating characteristic (ROC) curve analysis was conducted to examine sensitivity and specificity based on the area under the curve (AUC) as an indicator of the device's capacity to discriminate between asthma versus nonasthma cases.

RESULTS

ADAM data (cough counts) were negatively associated with forced expiratory volume in first second of expiration (FEV1) (r=-.26, P=.05), forced vital capacity (FVC) (r=-.31, P=.02), and overall asthma control (r=-.41, P=.009) and positively associated with daily activity limitation (r=.46, P=.01), nighttime (r=.40, P=.02) and daytime symptoms (r=.38, P=.02), and health care utilization (r=.61, P<.001). Device data were also a significant predictor of asthma control (β=-.48, P=.003), quality of life (β=-.55, P=.001), and health care utilization (β=.74, P=.004) after 3 months. The ROC curve analysis for the presence of asthma diagnosis had an AUC of 0.71 (95% CI 0.58-0.84), which was significantly different from chance (χ(2) 1=9.7, P=.002), indicating the device's discriminating capacity. The optimal cutoff value of the device was 0.56 with a sensitivity of 51.3% and a specificity of 72.7%.

CONCLUSIONS

This study demonstrates validity of ADAM as a symptom-monitoring device in teens with asthma. ADAM data reflect the current status of asthma control and predict asthma morbidity and quality of life for the near future. A monitoring device such as ADAM can increase patients' awareness of the patterns of cough for early detection of worsening asthma and has the potential for preventing serious and costly future consequences of asthma.

Reliability and predictors of resistive load detection in children with persistent asthma: a multivariate approach

OBJECTIVE

Resistive load detection tasks enable analysis of individual differences in psychophysical outcomes. The purpose of this study was to determine both the reliability and predictors of resistive load detection in children with persistent asthma who completed multiple testing sessions.

METHODS

Both University of North Carolina (UNC) Charlotte and Ohio University institutional review boards approved the research protocol. The detection of inspiratory resistive loads was evaluated in 75 children with asthma between 8 and 15 years of age. Each child participated in four experimental sessions that occurred approximately once every 2 weeks. Multivariate analyses were used to delineate predictors of task performance.

RESULTS

Reliability of resistive load detection was determined for each child, and predictors of load detection outcomes were investigated in two groups of children: those who performed reliably in all four sessions (n = 31) and those who performed reliably in three or fewer sessions (n = 44). Three factors (development, symptoms, and compliance) accounted for 66.3% of the variance among variables that predicted 38.7% of the variance in load detection outcomes (Multiple R = 0.62, p = 0.004) and correctly classified performance as reliable or less reliable in 80.6% of the children, χ(2)(12) = 28.88, p = 0.004.

CONCLUSIONS

Cognitive and physical development, appraisal of symptom experiences, and adherence-related behaviors (1) account for a significant proportion of the interrelationships among variables that affect perception of airflow obstruction in children with asthma and (2) differentiate between children who perform more or less reliably in a resistive load detection task.

Pediatric exercise-induced bronchoconstriction: contemporary developments in epidemiology, pathogenesis, presentation, diagnosis, and therapy

Exercise-induced bronchoconstriction is transient narrowing of the airways following strenuous exercise. It is the earliest sign of asthma and the last to resolve. EIB is found in 90 % of asthmatics and reflects underlying control of asthma. This review is focused on the contemporary developments in pediatric EIB: the epidemiology, pathogenesis, presentation, diagnosis and management. Proper diagnosis by objective pulmonary function and/or exercise challenge and therapy should allow the pediatric asthmatic to enjoy a healthy lifestyle including participation in the chosen sport.

Perception of airflow obstruction in patients hospitalized for acute asthma

BACKGROUND

Little is known about the perception of airflow obstruction in patients hospitalized for acute asthma.

OBJECTIVES

To evaluate patient perception of airflow obstruction at hospital discharge and at a 2-week follow-up visit and to determine whether symptom control and/or severity of airflow obstruction identified patients at risk for acute asthma after discharge.

METHODS

In a prospective cohort study of inner-city adults hospitalized for acute asthma from April 1, 2001, through October 31, 2002, symptom control (Asthma Control Questionnaire) and airflow obstruction (forced expiratory volume in 1 second [FEV1] percentage predicted) were evaluated at discharge and 2 weeks after discharge. We evaluated perception of airflow obstruction (symptom control vs FEV1 percentage predicted) and perception of change in airflow obstruction (change in symptom control vs percentage change in FEV1) between the 2 visits. Acute asthma after discharge was defined as an emergency department visit or hospitalization for asthma within 90 days of discharge.

RESULTS

In fifty-one participants, symptom control was not significantly associated with airflow obstruction at hospital discharge (P = .30), indicating poor perception of airflow obstruction. Among the 41 participants (80.4% of those enrolled) who completed the follow-up visit, change in symptom control was not significantly associated with change in airflow obstruction (P = .20), indicating poor perception of change in airflow obstruction. Greater airflow obstruction at follow-up (P = .02) and a smaller improvement in airflow obstruction (P = .03), but not symptom control, were associated with a higher risk of acute asthma after discharge.

CONCLUSIONS

Patients hospitalized for acute asthma have poor perception of airflow obstruction and change in airflow obstruction. Objective measurements of lung function should guide treatment decisions after discharge in this population.

Symptom perception in children with asthma: cognitive and psychological factors

OBJECTIVE

This study tested the differential effects of several cognitive and psychological variables on children's perception of asthma symptoms by use of an Asthma Risk Grid. Children's subjective and objective assessments of PEFR (peak expiratory flow rate) were characterized as representing perceptual accuracy, symptom magnification, and/or underestimation of asthma symptoms.

DESIGN

The study included 270 children with asthma (ages 7-17) and their primary caregivers who completed measures assessing cognitive and psychological factors and a 5 to 6 week symptom perception assessment.

MAIN OUTCOME MEASURES

Children's symptom perception scores by use of the Asthma Risk Grid.

RESULTS

Children's attentional abilities had more of a bearing on their symptom monitoring abilities than their IQ estimates and psychological symptoms. The more time children took on Trails and Cancellation Tasks and the fewer errors they made on these tasks, the more likely they were to perceive their asthma symptoms accurately. More time on these tasks was associated with more symptom magnification scores, and fewer errors were related to fewer symptom magnification scores. More errors and higher total scores on the Continuous Performance Task were associated with a greater proportion of scores in the danger zone.

CONCLUSION

Statistical support was provided for the utility of attentional-based instruments for identifying children who may have problems with perceptual accuracy, and who are at risk for asthma morbidity.

Patterns of asthma control perception in adolescents: associations with psychosocial functioning

OBJECTIVE

The purpose was to identify and describe the patterns of asthma control perception in relation to actual symptom reports in adolescents and to compare the group with accurate control perception with those of inaccurate perception in relationship to sociodemographic characteristics, illness-related factors, and psychosocial factors.

METHODS

A sample of 126 adolescents from 13 through 20 years of age participated in the study. Patterns of control perception were constructed based on participants' rating of their perception of asthma control and self-reported asthma symptoms using Latent Class Analysis. Analyses of variance (ANOVAs) and multinomial logistic regressions were computed for group comparisons.

RESULTS

Participants were classified into four groups according to the patterns of control perception. Accurate groups were divided into either the well-controlled (62%) or the poorly-controlled group (7%), and inaccurate groups were manifested inaccuracy either with nighttime symptoms (25%) or daytime symptoms (6%). Minority participants (p < 0.001) or those with low socioeconomic status (p < 0.001) were more likely to be represented in the inaccurate group than their counterparts. The well-controlled accurate group consistently reported higher asthma-related knowledge (p = 0.02), more positive attitude toward asthma (p < 0.001), fewer barriers to self-management (p = 0.04), and higher quality of life (p < 0.001) than the inaccurate group.

CONCLUSION

This study demonstrated that accuracy of asthma control perception can be classified into four criteria based on patterns of various asthma symptoms. Adolescents' tendency toward underperception was evident. The inaccurate groups are at greater risk for psychosocial impairments. This study underscores the importance of an intervention that improves the accuracy of asthma control perception in adolescents while promoting psychosocial well-being among adolescents with inaccurate perception.

Correlations between pulse oximetry and peak expiratory flow in acute asthma

Few studies are available concerning correlations between pulse oximetry and peak expiratory flow in children and adolescents with acute asthma. Although the Global Initiative for Asthma states that measurements of lung function and oximetry are critical for the assessment of patients, it is not clear if both methods should necessarily be included in their evaluation. Since there is a significant difference in cost between pulse oximetry equipment and peak expiratory flow devices, we determined whether clinical findings and peak expiratory flow measurements are sufficient to determine the severity of acute asthma. The present prospective observational study was carried out to determine if there is correlation between pulse oximetry and peak expiratory flow determination in 196 patients with acute asthma aged 4 to 15 years diagnosed according to the Global Initiative for Asthma criteria. Patients experiencing their first or second wheezing episode, with fever, related acute or chronic diseases, and unable to perform the peak expiratory flow maneuver were excluded. Measurements of peak expiratory flow and pulse oximetry were performed at admission and after 15 min of each inhaled salbutamol cycle. Correlations obtained by linear regression using the Pearson correlation coefficients (r) were 0.41 (P < 0.0001), 0.53 (P < 0.0001), 0.51 (P < 0.0001), and 0.61 (P < 0.0001) at admission and after the first, second and third cycles of salbutamol, respectively. These correlations showed that one measure cannot substitute the other (Pearson's coefficient <0.7), probably because they evaluate different aspects in the airways, suggesting that peak expiratory flow should not be used alone in the assessment of acute asthma in children and adolescents.

Symptom perception and functional morbidity across a 1-year follow-up in pediatric asthma

The purpose of this study was to examine the association between asthma symptom perception measured during a 5-6 week baseline and functional morbidity measured prospectively across a 1-year follow-up. Symptom perception was measured by comparing subjective ratings with peak expiratory flow rate (PEFR) and forced expiratory volume in one second (FEV(1)). We hypothesized that accurate symptom perception (ASP) would be associated with less functional morbidity. Participants consisted of 198 children with asthma ages 7-17 recruited from three sites. The children used a programmable electronic spirometer in the home setting to guess their PEFR prior to exhalation. Each "subjective" guess was classified as being in an ASP, dangerous symptom perception (DSP; underestimation of symptoms), or symptom magnification (SM; overestimation) zone based upon the corresponding measurement of PEFR or FEV(1). An index of functional morbidity was collected by parent report at baseline and across 1-year follow-up. A greater proportion of ASP blows and a lower proportion of DSP blows based on PEFR predicted less functional morbidity reported at baseline, independent of asthma severity and race/ethnicity. A greater proportion of ASP blows (using PEFR and FEV(1)) and a lower proportion of SM blows (using FEV(1)) predicted less functional morbidity across 1-year follow-up. Symptom perception was not associated with emergency department visits for asthma at baseline or across follow-up. In comparison to PEFR, FEV(1) more frequently detected a decline in pulmonary function that children did not report. Symptom perception measured in naturalistic settings was associated with functional morbidity at baseline and prospectively across 1-year follow-up. Support was found for including multiple measures of pulmonary function in the assessment of asthma symptom perception.

Home monitoring in asthma self-management

Peak flow monitoring of asthma came into vogue with the advent of asthma self-management programs. Because it offered an objective way to gauge asthma severity, it promised improvement in the accuracy of asthma monitoring over that attainable by symptom monitoring. This promise has not been fulfilled. The ensuing years have witnessed a debate concerning the relative merits of symptom and peak flow monitoring. The debate has focused both on the degree to which peak flow and symptom scores are related to one another and on the relative effectiveness of symptom and peak flow monitoring for asthma control. We review research relating to these topics. The work shows that the strength of the relationship between peak flow and symptoms is low to moderate and varies between individuals and that benefits of peak flow monitoring in asthma self-management provide, at best, no more than a small increment in effectiveness beyond that afforded by symptom monitoring.

Symptom perception in childhood asthma: the role of anxiety and asthma severity

This study tested the relationship of anxiety and asthma severity to symptom perception. Eighty-six children diagnosed with mild or moderate asthma had symptom perception and pulmonary function measured throughout methacholine challenge (to induce bronchoconstriction). Higher trait anxiety was associated with heightened symptom perception (controlling for pulmonary function) at baseline. Greater asthma severity was associated with blunted symptom perception (controlling for pulmonary function) at the end of methacholine challenge and with a slower rate of increase in symptom perception across methacholine challenge. These results suggest that anxiety plays a role when children's symptoms are mild, whereas medical variables such as severity play a role in perception of changes in asthma symptomatology as bronchoconstriction worsens.

Advancing the science of perceptual accuracy in pediatric asthma and diabetes

OBJECTIVES

To review research on perceptual accuracy in pediatric asthma and diabetes and to provide recommendations for future research efforts and clinical applications of the construct in these populations.

METHODS

A literature search was conducted using Medline and PsychInfo databases as well as the bibliographies of relevant articles.

RESULTS

Children and adolescents with asthma or diabetes evidence considerable variability in perceptual accuracy and frequently make clinically relevant errors that have the potential to affect self-management behavior.

CONCLUSIONS

Recommendations for future research include studying distinct types of perceptual errors, empirically supporting the relationship between perceptual accuracy and relevant outcomes, identifying factors related to perceptual inaccuracy, and conducting longitudinal research and intervention studies. Recommendations for applying the construct in clinical practice include adopting an individualized approach to symptoms to guide patient education and management, identifying patients prone to making clinically relevant errors, and developing and implementing interventions to improve accuracy.

Sex differences among children 2-13 years of age presenting at the emergency department with acute asthma

Hospitalization rates for asthma have been reported to be higher in males than females in children under age 15, but it is not clear whether this disparity reflects gender differences in prevalence, severity, or treatment. We performed a prospective cohort study as part of the Emergency Medicine Network. Patients aged 2-13 years who presented to the emergency department (ED) with acute asthma underwent a structured interview in the ED and another by telephone 2 weeks later. Of 1,602 patients, 61% (95% CI, 59-64%) were boys. Girls were slightly older than boys, although no material differences existed in acute presentation, chronic asthma characteristics, ED treatment, or ED course. There was no difference in admission rates for boys or girls (20% vs. 22%; P = 0.48). This finding persisted when adjusting for other factors in a multivariate logistic regression model. No sex differences were observed for relapse or ongoing exacerbation on univariate or multivariate analysis. These data suggest that asthma is not inherently more severe in boys with asthma compared to girls, and that the increased rate of hospitalizations in boys under age 13 is due to differences in prevalence, not severity.