A randomised controlled trial of the effect of automated interactive calling combined with a health risk forecast on frequency and severity of exacerbations of COPD assessed clinically and using EXACT PRO

Background: We have developed a winter forecasting service to predict when patients with COPD are at higher risk of an exacerbation and alert them via an automated telephone call. Aims: To assess the effect of the service and its ability to predict periods of increased risk. Methods: A 4-month prospective randomised controlled trial using clinical criteria and the EXACT PRO questionnaire to identify exacerbations. Patients were randomly allocated to receive alert calls. All patients completed a diary including the EXACT PRO questionnaire on a BlackBerry Smartphone each day. They were contacted and assessed if they appeared to be exacerbating. Results: 79 patients participated, 40 received alert calls. The exacerbation frequency per patient per week was significantly greater during periods of predicted high risk (0.086 +/- 0.010 v 0.055 +/- 0.010). The exacerbation frequency ( standard error of the mean, SEM) in patients receiving alert calls was lower (0.95 +/- 0.27 v 1.17 +/- 0.29) but this was not statistically significant. Fewer patients receiving alert calls had one or more EXACT event compared to the controls (34% v 53%, p=0.11), their duration was shorter (8.2 +/- 2.0 v10.1 +/- 1.9 days, p=0.481) and they were less severe (AUC 65 +/- 21 v 115 +/- 22, p=0.118). There were no significant differences in the mean change ( SEM) in SGRQ scores between the groups. Conclusions: The ability of the forecast to predict high risk periods was confirmed unequivocally. Alert calls appeared to reduce the frequency and severity of exacerbations but these effects did not reach statistical significance, perhaps because of the number of participants, lower than expected exacerbation rates, and the fact that there was contact with patients in both groups whenever they appeared to be exacerbating.