The effect of a peak flow-based action plan in the prevention of exacerbations of asthma. A randomized trial of peak-flow and symptom-based action plans in adults with moderate-to-severe asthma. [Hospitalization reduction by an asthma tele-medicine system].
To determine the effect of a symptom-based and a peak flow-based action plan in preventing acute exacerbations in subjects with poorly controlled asthma.
                A randomized controlled trial in which subjects who had required urgent treatment for their asthma were allocated to receive no action plan, a symptom-based plan, or a peak flow-based action plan.
                A university hospital asthma clinic.
                One hundred fifty subjects were recruited after attending an emergency department or a clinic for urgent treatment of asthma.
                All subjects received evaluation and education for asthma before being randomly allocated to receive no action plan, a symptom-based action plan, or a peak flowmeter and a peak flow-based action plan.
                Subjects were assessed by questionnaire at 3 and 6 months after enrollment with questions relating to their asthma control and their need for urgent treatment or hospital admission for asthma.
                At 6 months after enrollment, although all three intervention groups experienced improvement in their asthma control, there was a striking reduction in emergency department visits for asthma only in the peak flow-based action plan group (p=0.006). No significant difference in emergency visits was apparent between the symptom-based action plan and no action plan groups.
                We conclude that a peak flow-based action plan is effective, at least in the short term, in protecting patients with asthma against severe exacerbations of their disease. Peak flow meters (PFM) continue to be recommended as an important part of asthma self-management plans. It remains unclear if there is an advantage in using PFM in people with moderate-to severe asthma who are not poor perceivers of bronchoconstriction.
                Prospective, randomized controlled trial of 134 adults with moderate-to-severe asthma who did not have evidence of poor perception of bronchoconstriction on histamine challenge testing, who were recruited from inpatients and outpatients of a university teaching hospital. Comparison was made over 12 months of the effectiveness of written action plans using either peak flow monitoring or symptoms to guide management. Subjects were contacted at monthly intervals by telephone for reinforcement and evaluation of use of the action plans, and to provide ongoing education. Spirometry and PD20 histamine were measured at 3-monthly intervals. Measures of health care utilization and morbidity (asthma exacerbations; hospitalizations; emergency department (ED) visits; days absent from work or school due to asthma; medication use and a self-rating of asthma severity) were made monthly. A psychosocial questionnaire (attitudes and beliefs, state-trait anxiety, denial) was given at entry and at 12-months or at withdrawal from the study.
                There were significant improvements for both groups for hospitalizations, ED visits, days off from school or work, and PD20 histamine, but no between-group differences. Appropriate use of action plans was 85% in the symptoms group and 86% in the PFM group. For all subjects, those who subsequently had an ED visit had significantly higher levels of denial (P=0.04) and lower scores for self-confidence (P=0.04), compared to those who did not have an ED visit.
                Use of written action plans, combined with regular contact to reinforce self-management, improved airway reactivity and reduced health care utilization. However, use of PFM was not superior to symptom-based plans. We examined an effectiveness of a new asthma telemedicine system in reducing hospitalizations using a multi-site randomized control study. In this program, a nurse under physician supervision monitors the patient's airway status at home and provides instructions to individuals via the telephone, helping them manage exacerbations as well as reinforcing proper use of a zone-controlled management plan. Patients with a high risk for hospitalization were screened based on the numbers of emergency room visits and hospitalizations found in a previous study and randomly assigned to either the telemedicine or control group. After a six-month study period, an 83% reduction in hospitalization was demonstrated in the telemedicine group versus the control group, with a P value of 0.01. Improvement of peak expiratory flow and symptoms were also shown in the study group. We conclude that the key success factors in home asthma management for poorly controlled asthma patients are early detection of exacerbations through daily peak flow monitoring, compliance with prescribed daily prophylactic anti-inflammatory steroid medications, and immediate action as specified by a zone-controlled action plan upon the first signs of deterioration.
The evidence suggests that symptom-based WAP are superior to peak flow WAP for preventing acute care visits although there is insufficient data to firmly conclude whether the observed superiority is conferred by greater adherence to the monitoring strategy, earlier identification of onset of deteriorations, higher threshold for presentation to acute care settings, or the specific treatment recommendations.