Evaluation of the Healthdyne NightWatch System to Titrate CPAP in the Home

Abstract

Although a number of devices have been developed to monitor sleep and breathing in the home, there are few publications on methodologies by which CPAP can be titrated in the home setting. This study was conducted to determine the outcome of CPAP titration in the home using the Healthdyne NightWatch (NW) system. This home sleep-evaluation system was used to diagnose sleep apnea in 30 patients using a previously described methodology. These patients subsequently underwent CPAP titration in the home using the NW system, with modem technology allowing the transfer of data from the home to the laboratory. This group was compared with 30 patients who were diagnosed with sleep apnea using standard in-lab polysomnography and had CPAP titrated on a full night in the laboratory. Both groups were subsequently placed on CPAP at the appropriate pressure for 6-8 weeks, after which a full in-lab study was completed to assess CPAP efficacy at the prescribed pressure. Compliance was also determined using a pressure-activated monitor. No differences in any variable assessed could be found between the two groups. Mean compliance was 4.6+0.5 (SEM) and 4.3+0.5 hours of CPAP use per night for the home and in-lab groups respectively. Mean AHIs on the follow-up study were 7.4+1.2 and 7.6+1.6 events per hour for the home versus in-lab groups. Sleep stage distribution was also quite comparable between groups. As a result, this study suggests that sleep apnea can be diagnosed and CPAP titrated in the home with a similar outcome, at least at 6 to 8 weeks, to standard in-laboratory testing.