Apnea-hypopnea index supplied by CPAP devices: time for standardization?

Abstract Background/Objective For obstructive sleep apnea (OSA) patients on continuous positive airway pressure (CPAP) treatment, the apnea hypopnea index (AHI) is a key measure of treatment efficacy. However, the residual AHI is CPAP brand specific. Here, we studied changes in residual AHI in patients who used two different brands over their treatment history, Patients/Methods Using our CPAP telemonitoring database of 3102 patients, we compared the residual AHI of 69 patients before and after change in their CPAP device. Results A paired Wilcoxon signed-rank test revealed a significant difference between brands in the reported AHI, which might be clinically misleading. Conclusions These findings suggest that physicians should be alerted to the differences between brands and learned societies should push for standardization of AHI reporting.