847Interim analysis of the device-detected cardiac tachyarrhythmic events and sleep-disordered breathing (DEDiCATES)" study; focused on baseline characteristics
Authors: Gwag H B , Park S J , Park K M , On Y K , Kim J S 
Published: June 2020

Abstract

Funding Acknowledgements
This work is supported by Boston Scientific.
Background/introduction: Sleep-disordered breathing (SDB) is one of the common comorbidities in cardiac implantable electronic devices (CIED) patients. It’s feasible to detect SDB using specialized diagnostic function of CIEDs showing comparable performance in diagnostic accuracy of SDB to conventional polysomnography. To date, few studies have investigated the prognostic value of CIED-detected SDB in cardiovascular risk.

Purpose
In the Device-Detected CArdiac Tachyarrhythmic events and Sleep-disordered breathing (DEDiCATES) study, we aim to determine whether device-detected sleep-disordered breathing (SDB) events are associated with increased risk of cardiac arrhythmias or other cardiovascular (CV) outcomes. Here, we present interim baseline data of the study population to investigate the baseline prevalence and severity of device-detected SDB in CIED patients.

Methods
The study was designed as a prospective, multicenter, and observational study to include 600 patients. Eligible patients have dual chamber CIEDs with SDB detection function which reports the average number of sleep disturbance events per hour per night in the form of a Respiratory Disturbance Index (RDI). The daily RDI values were collected to measure the severity and burden of SDB. The baseline severity of SDB was determined according to RDI data recorded during the first 1 week, 1 month, and 3 ± 1 months after CIED implantation; patients with RDI≥ 30/h for at least one night are classified into the severe SDB group.

Results
A total of 313 patients who completed the first device interrogation at 3 ± 1 months were included for analysis. The mean age and CHA2DS2VASc score were 69 and 3.1, respectively. Forty-nine percent of patients were men, and 35.5% were classified as high risk for SDB by Berlin questionnaire. The rate of severe SDB increased with longer monitoring period (83.8% at 1week, 91.6% at 1 month, and 96.4% at 3 ± 1 months). There was no baseline demographic difference between the severe and non-severe SDB groups, except that baseline body mass index (BMI) was higher in the severe group (24.5% vs. 21.5%, p = 0.01). The mean RDI was 36.3, 34.2, and 33.0 per night during the first 1 week, 1 month, and 3 ± 1 months, respectively. Considering the limitation of the categorical criteria of baseline severity, we arbitrarily reclassified the patients according to median mean RDI value. Men were more frequent and BMI was higher in the above-mean RDI group compared to the below-mean RDI group. Using logistic regression analysis, we identified that BMI and male gender were associated with patients with above-mean RDI.

Conclusions
Conventional categorical classification of SDB severity seems to be limited in its ability to discriminate high risk patients. Thus, more suitable RDI-related variables need to be identified in future outcome analysis.
Abstract Figure. Prevalence of baseline severe SDB