Sleep quantity, quality are linked to stroke risk

Takeaway

• Having long nighttime sleep duration, taking long midday naps, and sleeping poorly predicted stroke risk among middle-aged and older adults.

Why this matters

• Usefulness for identifying patients at elevated risk.
• If a causative factor, poor sleep may be modifiable.

Key results

• During mean 6.2-year follow-up, 4.9% cohort experienced stroke.
• Relative to peers with intermediate sleep duration (from 7 hours/night to <8 hours/night), participants with long sleep duration (≥9 hours/night) had elevated stroke risk (HR, 1.23; 95% CI, 1.07-1.41).
• Compared with peers taking midday naps of 1-30 minutes, participants napping >90 minutes had elevated stroke risk (HR, 1.25; 95% CI, 1.03-1.53).
• Findings were similar for ischemic stroke alone.
• Relative to peers with good sleep quality, participants with poor sleep quality had elevated risks for:
  • Total stroke (HR, 1.29; 95% CI, 1.09-1.52),
  • Ischemic stroke (HR, 1.28; 95% CI, 1.05-1.55), and
  • Hemorrhagic stroke (HR, 1.56; 95% CI, 1.07-2.29).

Study design

• Chinese prospective cohort study: 31,750 retirees (mean age, 61.7 years) initially free of stroke, coronary heart disease, cancer.
• Main outcome: incident stroke.
• Funding: National Natural Scientific Foundation of China; National Key Research and Development Program of China.

Limitations

• Sleep parameters self-reported, with limited questions.
• Information on sleep disorders (e.g., snoring) not collected.
• Unknown generalisability.