Arrhythmias & electrophysiology
Habitual sleep duration and QT variability index: Correlates of ventricular repolarization lability and all-cause mortality
Authors' conclusion
In adults without sleep-disordered breathing, short and long habitual sleep duration were associated with increased ventricular repolarization lability. Elevated QTVI independently predicted all-cause mortality, particularly in short sleepers, suggesting that sleep duration may influence electrophysiological vulnerability and arrhythmic risk.
Study context
- Population
- Adults in the Sleep Heart Health Study without sleep-disordered breathingadults analyzed
- Participants
- 1,123 adults
- Comparison
- Habitual sleep duration categories vs 8 hours of habitual sleep; QT variability index (QTVI) and all-cause mortality
- Outcome
- QTVI
Main finding
As reported in the abstract
ΔQTVI (95% CI)
≤5 vs 8 (reference)higher QTVI with short sleep
0.18(0.05–0.31)
≥9 vs 8 (reference)higher QTVI with long sleep
0.15(0.02–0.28)
Further findings
All-cause mortality by QTVI
| Hazard ratio (95% CI) | ||
|---|---|---|
| Highest quartile of QTVI | 2.14 (1.45–3.17) | |
| 0.20.5125Hazard ratio (log scale) |
QTVI-mortality association by sleep duration
| Hazard ratio (95% CI) | ||
|---|---|---|
| QTVI, those reporting ≤5 hours of sleepStrongest effect | 3.12 (1.85–5.26) | |
| 0.20.5125Hazard ratio (log scale) |
- QTVI-mortality association by sleep duration: P = .04 for interaction
All-cause mortality by QTVI
- Higher QTVI predicted greater mortality risk
Original publication
Habitual sleep duration and QT variability index: Correlates of ventricular repolarization lability and all-cause mortality. Heart Rhythm. Published 25 August 2025. doi:10.
Composed by AI from the published abstract and checked against it. How Briefs are made →