Wensley D, Silverman M. Am J Respir Crit Care Med. 2004;170:606–612
Purpose of the Study.
To determine if the addition of peak expiratory flow (PEF) recordings to a symptom-based self-management plan improved outcome in schoolchildren with asthma.
Children (n = 90), aged 7 to 14 years with physician-diagnosed asthma, who are on regular inhaled corticosteroid therapy.
Children were randomized to receive a management plan based on either symptoms alone or symptoms plus PEF readings for 12 weeks. Children were asked to perform twice-daily spirometry (using an electronic recording spirometer that revealed PEF results only to the symptoms-plus-PEF group) and record a symptom diary. The child and the main caregiver were taught self-management at a training session. A printed plan, based on the child’s best previous PEF and incorporating the child’s own medication regime, was color coded: green: PEF > 70%, few symptoms (carry on as usual); yellow: PEF 50% to 70% after β-2 agonist (double-inhaled corticosteroid as well as taking additional β-2-agonist therapy); red: PEF < 50% after taking additional inhaled β-2 agonist, severe symptoms (commence oral prednisolone and/or seek medical help).
There were no differences between groups in mean symptom score or in spirometric lung function, PEF, quality-of-life score, or reported use of health services. During acute episodes, children responded to changes in symptoms by increasing their inhaled steroids at a mean PEF value of >70% of best so that overall PEF did not contribute to this important self-management decision.
This trial does not support the hypothesis that the routine incorporation of PEF monitoring into guided self-management protocols for schoolchildren with asthma improves the outcome. Knowledge of PEF did not enhance self-management even during acute exacerbations.
Amen. TheExpert Panel Report: Guidelines for the Diagnosis and Management of Asthma—Update on Selected Topics 2002 (National Institutes of Health Pub. 02-5075) found that “evidence neither supports nor refutes the benefits of written action plans based on peak-flow monitoring compared with symptom-based plans in improving health care utilization, symptoms, or lung function” and even further that “data are insufficient to support or refute the benefits of using written asthma action plans compared with medical management alone.” A recent Cochrane systematic review also found no difference in any outcome measure when comparing written action plans based on peak-flow measurements to those based on symptoms or any difference in outcomes when formal written action plans were or were not provided. I believe we have ample evidence to abandon the routine use of peak-flow meters.