Book Description

Asthma is the most common chronic disease of childhood. Preventive asthma medication has been shown to decrease lung inflammation and improve both disease control and quality of life. Sub-optimal adherence with preventive medication is common. Non-adherence has been linked with significant morbidity and increased healthcare utilisation, both leading to increased overall healthcare costs. This thesis contributes to the body of evidence regarding adherence by: 1. Validating an electronic monitoring device (EMD) designed to measure adherence. 2. Exploring factors association with non-adherence in young children with asthma. 3. Examining the accuracy of subjective measures of adherence including parent report and physician s estimate of adherence. 4. Demonstrating that a novel spacer incorporating an incentive device (Funhaler) does not increase adherence in young children with asthma. 5. Demonstrating that measuring adherence and providing feedback about medication usage during a consultation increases adherence in children with poorly controlled asthma. An EMD, the Smartinhaler, was shown to accurately record actuations with a pressurised metered dose inhaler. It compared favourably with a previously validated device, the Doser. An observational study involving 50 young children with asthma found that the reported level of adherence by their parents correlated poorly with data from an EMD even when the question was phrased in a non-judgemental fashion and prefaced by a normalising statement. An estimate of adherence by the child's treating physician was shown to be no more likely to correctly identify non-adherence than would be expected by chance alone. Factors associated with non-adherence were explored and adherence was found to correlate inversely with the degree to which carers reported finding parenting stressful. A novel spacer incorporating an incentive device (spinning disk and whistle), the Funhaler, has been reported to be to be associated with increased adherence based on parental report. This thesis includes a randomised controlled trial involving 44 children comparing adherence with preventive medication by those using the Funhaler and a control group using a standard spacer. No difference was found between the two groups in terms of adherence or disease control over a period of three months. Measuring adherence using an EMD and providing feedback regarding this data during the subsequent consultation was evaluated in a randomised controlled study involving 26 children with poorly controlled asthma. The mean adherence in the group receiving feedback with regard to their adherence was found to be 21% higher than adherence by children in the control group whose measured adherence remained unknown to them, their parents and their treating physician.