Guidelines for the diagnosis and management of asthma: accepting the challenge

A recombinant DNA plasmid encoding the human interleukin-5 breaks immunological tolerance and inhibits airway inflammation in a murine model of asthma

BACKGROUND

Eosinophils play a pivotal role in the generation of asthma inflammation. Interleukin (IL)-5 is the major activator of eosinophils. We hypothesize that modulating IL-5 activity could be an effective strategy for asthma therapy. In this study, we tested whether the plasmid encoding human IL-5 as a xenogeneic DNA vaccine could induce the production of autoantibodies, and be used for asthma treatment.

METHODS

A eukaryotic plasmid encoding the human IL-5 was constructed, and used as a DNA vaccine. A mouse model of asthma was established to observe its antiasthma activities. Eosinophils in tissue, blood and the bronchoalveolar lavage were stained and counted. Airway hyperresponsiveness (AHR) was determined by whole body plethysmography. Antibody characters and cytokines were detected with immunological methods.

RESULTS

Immunization with a plasmid encoding the human IL-5 as DNA vaccine reduced airway inflammation, reversed Th2 cytokines, and decreased AHR in mice. In addition, this immunization induced the production of polyclonal antibodies that were cross-reactive with native murine IL-5, and IgG1 and IgG2a were the major subclasses. Adoptive transfer of the purified antibodies from the sera of mice immunized with the plasmid encoding the human IL-5 resulted in similar antiasthma effects.

CONCLUSIONS

Our results suggest that active vaccination against IL-5 may be a rational therapeutic approach for the treatment of asthma and potentially other eosinophilic disorders.

Computer-based decision support for pediatric asthma management: description and feasibility of the Stop Asthma Clinical System

Clinical guidelines can assist in the management of asthma. Decision support systems (DSSs) can enhance adherence to clinical guidelines but tend not to provide clinicians with cues for behavioral change strategies to promote patient self-management. The Stop Asthma Clinical System (SACS) is a DSS designed for this purpose. To assess feasibility, seven clinicians used SACS to guide well visits with 26 predominantly persistent pediatric asthma patients. Data were collected via survey and in-depth semi-structured interviews. SACS improved assessment of asthma severity and control, classification of and intervention in medicine and environmental trigger management problems, and development of an action plan (all p < 0.05). Clinician-patient communication was enhanced. The primary challenge was that SACS increased clinic visit time. SACS can enhance clinician behavior to improve patient asthma self-management, but more studies are indicated to mitigate temporal constraints and evaluate impact on clinician and patient communication and behavior as well as clinical outcomes.

Development of an expert system knowledge base: a novel approach to promote guideline congruent asthma care

Existing guidelines for the clinical management of asthma provide a good framework for such tasks as diagnosing asthma, determining severity, and prescribing pharmacological treatment. Guidance is less explicit, however, about establishing a patient-provider partnership and overcoming barriers to asthma management by patients in a way that can be easily adopted in clinical practice. We report herein the first developmental phase of the "Stop Asthma" expert system. We describe the establishment of a knowledge base related to both the clinical management of asthma and the enhancement of patient and family self-management (including environmental management). The resultant knowledge base comprises 142 multilayered decision rules that describe clinical and behavioral management in three domains: 1) determination of asthma severity and control; 2) pharmacotherapy, including prescription of medicine for chronic maintenance, acute exacerbation, exercise pretreatment, and rhinitis relief; and 3) patient self-management, including the process of intervening to facilitate the patient's asthma medication management, environmental control, and well-visit scheduling. The knowledge base provides a systematic and accessible approach for intervening with family asthma-related behaviors.

Variations in asthma care by race/ethnicity among children enrolled in a state Medicaid program

OBJECTIVE

To examine differences in the process of care for Medicaid-enrolled white, Hispanic, and black children with asthma.

DESIGN

Retrospective cohort study using Medicaid claims data to analyze the process of asthma care in 1994, including all white (non-Hispanic), black (non-Hispanic), and Hispanic children (aged 2-18 years) with asthma in the non-health maintenance organization portion of the Massachusetts Medicaid program (N = 5773). Main outcome measures included performance on 6 claims-based process-of-care measures that reflect national guidelines. Measures addressed primary and specialty care for asthma, appropriate asthma pharmacotherapy, and timely follow-up care after asthma emergency department (ED) visits and hospitalizations.

RESULTS

Controlling for case mix, provider type, disability status, age, and gender, Hispanic children with asthma were 39% less likely than white children to have a specialist visit for asthma (odds ratio [OR]: 0.61; confidence interval [CI]: 0.46-0.81) and 41% less likely to receive a follow-up visit within 5 days of being seen in the ED for asthma (OR: 0.59; CI: 0.36-0.95). However, Hispanic children received better care in 2 respects. They were 16% more likely than white children to receive a minimum of 2 asthma visits per year (CI: 1.01-1.34) and 27% less likely to be overprescribed beta-agonist medications (OR: 0.73; CI: 0.54-0.99). Black children were 64% less likely than white children to receive timely follow-up care after being seen in the ED for asthma (OR: 0.36; CI: 0.18-0.73). There were no racial/ethnic differences in the prescribing of antiinflammatory medications or timely follow-up care after an asthma hospitalization.

CONCLUSIONS

This study demonstrates important differences in the process of care experienced by racial/ethnic subpopulations within a Medicaid population, which may help explain differential outcomes. Efforts to improve asthma outcomes should target specific areas in which black and Hispanic children may be receiving suboptimal care.

Anticholinergic agents for chronic asthma in adults

BACKGROUND

Anticholinergic agents such as ipratropium bromide are sometimes used in the treatment of chronic asthma. They effect bronchodilation and have also been used in combination with beta2-agonists in the management of chronic asthma.

OBJECTIVES

To examine the effectiveness of anticholinergic agents versus placebo and in comparison with beta2-agonists or as adjunctive therapy to beta2-agonists.

SEARCH STRATEGY

The Cochrane Airways Group asthma and wheeze database was searched with a pre-defined search strategy. Searches were current as of August 2003. Reference lists of articles were also examined.

SELECTION CRITERIA

Randomised trials or quasi-randomised trials were considered for inclusion. Studies assessing an anticholinergic agent versus placebo or in combination/comparison with beta2-agonists were included. In practice, all beta2-agonists were short acting. Short-term (less than 24 hours duration) and longer-term studies were separated; the latter are reported in this review and the former in the review, "Anticholinergic agents for chronic asthma in adults short term".

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed abstracts for retrieval of full text articles. Papers were then assessed for suitability for inclusion in the review. Data from included studies were extracted by two reviewers and entered into the software package (RevMan 4.2). We contacted authors for missing data and some responded. Adverse effect data were analysed if reported in the included studies.

MAIN RESULTS

The studies analysed were in two groups: those comparing anticholinergics with placebo and those comparing the combination of anticholinergics with short acting beta2-agonists versus short acting beta2-agonists alone. The former group had 13 studies involving 205 participants included in this review, and the latter 9 studies involving 440 patients. Generally methodological quality was poorly reported, and there were some reservations with respect to the quality of the studies. Despite the limited number of studies that could be combined, anticholinergic agents in comparison with placebo resulted in more favourable symptom scores particularly in respect of daytime dyspnoea (WMD -0.09 (95%CI -0.14, -0.04, 3 studies, 59 patients). Daily peak flow measurements also showed a statistically significant improvement for the anticholinergic (e.g. morning PEF: WMD =14.38 litres/min (95%CI 7.69, 21.08; 3 studies, 59 patients). However the clinical significance is small and in terms of peak flow measurements equates to approximately a 7% increase over placebo. The more clinically relevant comparison of a combination of anticholinergic plus short acting beta2-agonist versus short acting beta2-agonist alone gave no evidence in respect of symptom scores or peak flow rates of any significant differences between the two regimes. Again there are reservations with respect to the quality of the information from which these conclusions are drawn.

REVIEWERS' CONCLUSIONS

Overall this review provides no justification for routinely introducing anticholinergics as part of add-on treatment for patients whose asthma is not well controlled on standard therapies. This does not exclude the possibility that there may be a sub-group of patients who derive some benefit and a trial of treatment in individual patients may still be justified. The role of long term anticholinergics such as tiotropium bromide has yet to be established in patients with asthma and any future trials might draw on the messages derived from this review.

Development, content, and process evaluation of a short self-management intervention in patients with chronic diseases requiring self-care behaviours

Many patients with asthma, diabetes, and heart failure do not succeed in integrating the required self-management behaviours into their lives, and fail to attain optimal disease control. The purpose of this study was to describe the development of a theory-driven intervention to enhance self-management that would be appreciated and accepted by participants and providers. Based on self-regulation theory and proactive coping, the program emphasised goal-setting and the planning of behaviour. In five 2h group sessions, participants first decided upon their own goal and behaviours they wanted to change. Next, they wrote an action-plan to implement these behavioural intentions. Behavioural rehearsal and self-monitoring took place between the sessions. Participants and nurse providers evaluated the intervention positively. Evaluations were unrelated to patients' health at baseline, or to feelings of self-efficacy regarding self-management. But patients of older age, lower education, or no current employment responded best to the intervention.

Comparing asthma care provided to Medicaid-enrolled children in a Primary Care Case Manager plan and a staff model HMO

OBJECTIVE

To examine differences in selected processes of asthma care provided to Medicaid-enrolled children in a state-administered Primary Care Case Manager (PCCM) plan and a staff model health maintenance organization (HMO).

METHODS

Retrospective cohort study assessing performance on 6 claims-based processes of care measures that reflect aspects of pediatric asthma care recommended in national guidelines. Analyzed Medicaid and HMO claims and encounter data for 2365 children with asthma in the Massachusetts Medicaid program in 1994.

RESULTS

There were no plan differences in asthma primary care visits, asthma pharmacotherapy or follow-up care after asthma hospitalization. Children in the HMO were only 54% as likely (confidence interval [CI]: 0.37-0.80; P<.01) as those in the PCCM plan to experience an asthma emergency department (ED) visit or hospitalization. HMO-enrolled children were only half as likely (CI: 0.38-0.64; P<.001) to meet the National Committee for Quality Assurance (NCQA) definition for persistent asthma and only 32% as likely (CI: 0.19-0.56; P<.001) to have prior asthma ED visits or hospitalizations relative to children in the PCCM plan. Controlling for case mix and other covariates, children in the HMO were 2.9 times as likely (CI: 1.09-7.78; P<.05) as children in the PCCM plan to receive timely follow-up care (within 5 days) after an asthma ED visit and 1.8 times as likely (CI: 1.05-3.01; P<.05) as those in the PCCM plan to receive a specialist visit during the year.

CONCLUSIONS

In this study, the HMO served a less sick pediatric asthma population. After controlling for case mix, the staff model HMO provided greater access to asthma specialists and more timely follow-up care after asthma ED visits relative to providers in the state-administered PCCM plan. Further understanding of the impact of these differences on clinical outcomes could guide asthma improvement efforts.

An exploration of the skills needed for inhalation therapy in schoolchildren with asthma in Taiwan

BACKGROUND

Clinical observation has shown that many asthma-affected children and their parents are not familiar with appropriate techniques for inhaler use. This may result in misuse, overdose, or diminished response of the administered therapeutic drugs, or may even result in unnecessary, repeated hospitalization. Inappropriate inhalation technique is hazardous to the safety of children with asthma and unnecessarily increases costs resulting from unnecessary rehospitalization.

OBJECTIVE

We designed a study to evaluate the skills needed for inhaler use among children with asthma in Taiwan.

SUBJECTS AND METHODS

Schoolchildren with asthma, aged 8 to 13 years, were asked to demonstrate their inhalation technique. The inhalers used in this study were either metered-dose inhalers or dry-power inhalers. Assessment of the inhalation technique was made using a standardized inhaler checklist. A higher score indicates greater skill using the inhaler.

RESULTS

This study surveyed 132 schoolchildren with asthma. Of those, only 23 (17.4%) asthmatic children who received inhalation therapy revealed good compliance with their medication regimens. No child was observed to have completed all inhaler techniques correctly. Those family members who participated in educational programs and who received instruction from health teams had higher scores for the inhaler checklist (P < 0.05). It was found that children who inhaled medication unaided had a better knowledge of asthma, and their drug inhalation technique was also more skillful (P < 0.03). By multiple regression analysis, we found that determinants of a child's skill at performing the inhalation maneuver included: number of asthma attacks within the preceding year, unaided application of inhaler therapy, older subject age, potential for subjects to receive instructions from parents regarding inhaler use, subjects reading related publications, and the family's degree of satisfaction with the physician's educational program. These variables contributed a total of 23% to variance in the subjects' inhalation technique.

CONCLUSION

This study revealed that most asthmatic children being treated with inhaler medication do not use such devices appropriately. More aggressive asthma education is necessary in Taiwan.

Provider adherence to a clinical practice guideline for acute asthma in a pediatric emergency department

Critics of the use of clinical practice guidelines (CPGs) in an emergency department (ED) setting believe that they are too cumbersome and time-consuming, but to the best of the authors' knowledge, potential barriers to CPG adherence in the ED have not been prospectively evaluated.

OBJECTIVES

To measure provider adherence to an ED CPG based on National Asthma Education and Prevention Program (NAEPP) recommendations, and to determine factors associated with provider nonadherence.

METHODS

Prospective, cohort study of children aged 1-18 years with the diagnosis of an acute exacerbation of asthma who were seen in a pediatric ED and requiring admission, as well as a random selection of children discharged to home following pediatric ED care. The following adherence parameters were assessed: at least three nebulized albuterol treatments in the first hour; early steroid administration (after the first nebulizer treatment); clinical assessments using pulse oximetry and peak expiratory flow (PEF) (for children >6 years old); and use of a clinical score to assess acute illness severity (Asthma Severity Score). Nonadherence was defined as any deviation of the above parameters.

RESULTS

Between July 1, 1998, and June 30, 1999, 369 patients were studied. Of these, 38% (139) were discharged to home, 38% (140) were admitted to the observation unit, and 24% (90) were admitted to the inpatient unit. Illness severities at initial presentation to the ED were: 24% (86) had mild exacerbations, 59% (212) had moderate exacerbations, and 17% (62) had severe exacerbations. Sixty-eight percent (95% CI = 63% to 73%) of the patients were managed with complete adherence to the CPG. Of the 32% with some form of nonadherence, most (63%) were children older than 6 years; in this group 64% (48/75) were nonadherent due to lack of PEF assessment. When PEF assessment was disregarded, an 83% (95% CI = 79% to 87%) adherence to the CPG was achieved. Other nonadherence factors included: lack of at least three nebulized albuterol treatments provided timely within the first hour (5%); delay in steroid administration (6%); lack of pulse oximeter use (0.5%); and failure to record clinical score to assess severity (1.1%). Patient age, illness severity (acute and chronic), first episode of wheezing, and high ED volume periods (evenings and weekends) did not worsen adherence.

CONCLUSIONS

Clinical practice guidelines can be used successfully in the pediatric ED and provide a more efficient management and treatment approach to acute exacerbations of childhood asthma. With a systematic and concise CPG, barriers to adherence in a pediatric ED appear to be minimal, with the exception of using PEF in the routine ED assessment.

Mometasone furoate administered once daily is as effective as twice-daily administration for treatment of mild-to-moderate persistent asthma

BACKGROUND

Despite current recommendations, many patients with persistent asthma are still treated with bronchodilators alone.

OBJECTIVE

The safety and efficacy of two once daily dosing regimens (200 microg and 400 microg) of mometasone furoate (MF) administered in the morning by using a dry-powder inhaler (DPI) were compared with those of a twice daily dosing regimen (200 microg administered twice daily) in patients with mild-to-moderate persistent asthma previously taking only inhaled beta(2)-adrenergic agonists.

METHODS

All patients (306 patients; age range, 12-70 years) were given a diagnosis of asthma for at least 6 months before enrollment in this 12-week, placebo-controlled, double-blind, randomized study. The primary efficacy variable was change in FEV(1) from baseline to endpoint (last evaluable visit).

RESULTS

At endpoint, FEV(1) was significantly improved (P < or =.02) after MF-DPI 400 microg once daily morning treatment and MF-DPI 200 microg twice daily treatment (16.0% and 16.1%, respectively) compared with placebo (5.5%). The improvement seen with MF-DPI 200 microg once daily morning treatment (10.4%) was not significantly different from that with placebo. Secondary efficacy variables also showed significant improvement for the MF-DPI 400 microg once daily morning treatment group and the MF-DPI 200 microg twice daily treatment group compared with the placebo group. All doses of MF administered by means of a DPI were well tolerated.

CONCLUSION

This is the first study to demonstrate that a total daily dose of 400 microg of MF administered by means of a DPI is an effective treatment for patients with mild-to-moderate persistent asthma previously taking only inhaled beta(2)-adrenergic agonists. This treatment was equally effective when administered either as a once daily or twice daily regimen.