Markers of ventricular repolarization and overall mortality in sleep disordered breathing

Salma I. Patel, Wojciech Zareba, Bonnie LaFleur, Jean Phillipe Couderc, Xiaojuan Xia, Raymond Woosley, Imran Y. Patel, Daniel Combs, Saif Mashaqi, Stuart F. Quan, Sairam Parthasarathy

Research output: Contribution to journalArticlepeer-review

1 Scopus citations


Introduction: Variability and prolongation of ventricular repolarization – measured by changes in QT interval and QT variability are independently associated with ventricular arrhythmias, sudden death, and mortality but such studies did not examine the role of sleep-disordered breathing. We aimed to determine whether sleep-disordered breathing moderated the association between measures of ventricular repolarization and overall mortality. Methods: Eight hundred participants were randomly selected from each of the following four groups in the Sleep Heart Health Study: mild, moderate, severe or no sleep disordered breathing (n = 200 each). Overnight electrocardiograms were analyzed for QTc duration and QT variability (standard deviation of QT intervals, normalized QT interval variance and the short-term interval beat-to-beat QT variability). Cox proportional hazards penalized regression modeling was used to identify predictors of mortality. Results: Eight hundred of 5600 participants were randomly selected. The participants (68 ± 10 years; 56.8% male) were followed for an average of 8.2 years during which time 222 (28.4%) died. QTc, SDQT, and QTVN were associated with the presence of SDB (p = 0.002, p = 0.014, and p = 0.024, respectively). After adjusting for covariates, the presence of sleep-disordered breathing did not moderate the association between QTc length, QT variability and mortality (p > 0.05). Conclusion: Sleep-disordered breathing was associated with some measures of ventricular repolarization. However, sleep-disordered breathing was not an effect modifier for the relationship between QTc and QT variability and mortality.

Original languageEnglish (US)
Pages (from-to)9-15
Number of pages7
JournalSleep Medicine
StatePublished - Jul 2022


  • Mortality
  • QT interval
  • QT variability
  • Sleep apnea
  • Sleep disordered breathing
  • Ventricular repolarization

ASJC Scopus subject areas

  • General Medicine


Dive into the research topics of 'Markers of ventricular repolarization and overall mortality in sleep disordered breathing'. Together they form a unique fingerprint.

Cite this