Takeaway
- Self-reported insomnia symptoms increased risk for cardiovascular disease (CVD), and risk rose with number of symptoms.
Why this matters
- Insomnia may be a modifiable risk factor.
Key results
- 3 insomnia symptoms increased risk for total CVD:
- Difficulties initiating/maintaining sleep (adjusted HR [aHR], 1.09; 95% CI, 1.07-1.11).
- Early morning awakening (aHR, 1.07; 95% CI, 1.05-1.09).
- Daytime dysfunction (aHR, 1.13; 95% CI, 1.09-1.18).
- The 3 insomnia symptoms also increased risk for:
- Ischaemic heart disease individually (HRs, 1.13, 1.09, 1.17; P<.05 for each).
- Ischaemic stroke individually (HRs, 1.06, 1.07, 1.09; P<.05 for each).
- Risks increased with number of symptoms.
- Versus peers reporting none, individuals reporting all 3 had elevated risks for:
- Total CVD (HR, 1.18; 95% CI, 1.13-1.24).
- Ischaemic heart disease (HR, 1.22; 95% CI, 1.13-1.32).
- Ischaemic stroke (HR, 1.10; 95% CI, 1.02-1.19).
- Symptoms more strongly linked to risk in younger adults, nonhypertensive individuals.
Study design
- Chinese prospective cohort study of 487,200 individuals aged 30-79 years free of stroke, coronary heart disease, cancer at baseline.
- Main outcomes: total CVD, individual CVDs during median 9.6-year follow-up.
- Funding: National Key Research and Development Program of China; others.
Limitations
- Symptoms subjectively assessed.
- Reliance on registries, insurance databases for outcomes.
- Confounding.
- Uncertain generalizability.
References
References