Health Technology Assessment (Jan 2000)
Early asthma prophylaxis, natural history, skeletal development and economy (EASE): a pilot randomised controlled trial.
Abstract
OBJECTIVES: (1) To establish recruitment rates of newly presenting asthmatic children. (2) To establish acceptability of study protocols. (3) To pilot age-specific quality of life (QoL) assessment. (4) To assess short-term (6 months) outcomes of inhaled corticosteroids (ICS) treatment. (5) To refine sample size calculations for a definitive study. DESIGN: A randomised pragmatic longitudinal trial design was used, with no blinding or placebo, to examine early ICS introduction similar to its use in practice. Subjects were assessed at entry, 3 and 6 months. SETTING: Subjects were recruited from six general practices. Children under 6 years were assessed at the Craig Research and Investigation Unit, Royal Aberdeen Children's Hospital, or their family home, and subjects 6 years and over were assessed at their general practice. SUBJECTS: Children (aged 6 months-16 years) with symptoms suggestive of asthma/wheeze that had commenced no longer than 12 months before were identified retrospectively and prospectively from general practices. Subjects were also required to be naïve to prophylactic therapy with no other lung disease/concomitant illness. INTERVENTIONS: Subjects were randomised to ss2-agonist (ss2-only group) or ss2-agonist and ICS (ICS group) for 6 months. Physicians could later prescribe ICS in controls if needed. MAIN OUTCOME MEASURES: (1) Pulmonary function. (2) Asthma symptom diary. (3) Symptomatic health status questionnaire. (4) Caregiver's and child's QoL. (5) Growth. (6) Bone mass. (7) Bone turnover. (8) Economic issues. RESULTS: Of over 15,000 children yielded from general practice records, 11% had symptoms suggestive of asthma/wheeze, and two-thirds of these already used ICS. Of the remaining, 141 subjects met the criterion of early asthma, and 86 were randomised. Two-thirds of those randomised were < 6 years old, the males:females ratio was 2:1, and 67% had a family history of atopy. RESULTS - PHYSIOLOGICAL DEVELOPMENT: Pulmonary function did not significantly improve in the older children. Although tidal breathing measures in the pre-school children were significantly higher at 6 months in the ss2-only group, there was great variability. Incidence of wheeze and night-time cough reduced equally in both groups. Reduction of night-time symptom score and reliever use, and increase in symptom-free days were only significant in the ss2-only group. No significant differences were found in growth and bone mass between the two groups, but bone metabolism was significantly reduced at 6 months in the ICS group. RESULTS - PSYCHOLOGICAL DEVELOPMENT: The caregiver's QoL questionnaire was sensitive to child symptom changes over 3 months, but absolute impact of child symptoms on their QoL varied, whereas the child-centred questionnaire was not sensitive to change. RESULTS - ECONOMICS: There were no significant differences in medical consultation costs between the groups, but, as expected, prescription costs in the ICS group were higher over 6 months. Combined healthcare costs were significantly higher for patients assigned to ICS, but there were no significant differences in any effectiveness measures between the groups. CONCLUSIONS: Most (96%) of the proposed sample was recruited, and the low drop-out rate (8%) demonstrated acceptability of the study protocol. Most children first presenting with symptoms suggestive of asthma were < 6 years old and represented a group biased towards mild to moderate asthma, or virally induced wheeze. The caregiver's QoL questionnaire was found to better reflect a child's symptom changes than a child-centred instrument. In the short term, no adverse effects were seen on growth, but ICS treatment significantly reduced bone metabolism. Most of the young children with asthma/wheeze improved over time with ss2-agonist treatment alone, and clinical benefits of early ICS intervention amongst these children were not detected; however, there was inadequate power in this pilot study to establish this. (AB