Meta-analysis on COPD: Comment on ‘Home telehealth for chronic obstructive pulmonary disease: a systematic review and meta-analysis. by J Polisena et al. ’

We refer to the meta-analysis on home telehealth in chronic obstructive pulmonary disease (COPD) by Polisena et al. published in 2010. ¹ The authors reported that the risk ratio for mortality was higher for patients who had telephone follow-up than for those patients who had usual care, although they also stated that the difference was not significant.

However, in the Polisena et al. meta-analysis (Figure 2 page 125), the risk ratio in one of the constituent studies appears to be incorrect: the number of deaths in the study by Borbeau et al. ² seems to have been transposed during the calculation of risk ratio. On page 587 of the latter paper, the flow diagram shows there were nine deaths in the usual care arm and five deaths in the intervention arm. Borbeau et al. concluded that telephone follow up was not associated with increased mortality.

This anomaly needs to be clarified as the meta-analysis by Polisena et al. is being cited as evidence of harm in COPD through telehealth, most recently in the BMJ. ³

We note that in the context of a few small studies with high heterogeneity, one should perhaps await further research before drawing a final conclusion.