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Population study: followed a group

Study of 13,078 Chinese adults: sleep under 5 hours linked to more heart disease

He and colleagues · The American journal of cardiology · 2025

Original title: The Relationship Between Sleep Duration and Cardiovascular Disease: A Prospective Cohort Study Based on Charls.

Under review. A person has not yet checked this summary against the paper. It is written from the PubMed abstract. Until a person checks it, search engines are asked not to list this page.

What the study found

Points to benefit

Sleep under 5 hours was linked to higher heart disease risk, and 6 to 8 hours to the lowest risk. Each extra hour of sleep went with about 9% lower odds of CVD.

The study at a glance

Type of study
Population study: followed a group
Who or what was studied
13,078 people · Chinese adults aged 45 and over in a national aging study
What was tested
Sleep hours (under 5 h up to 8 h) and whether people had heart disease, across three survey waves
What it measured
The question itself: death, heart disease and other health outcomes
Who has a stake
No stake declared
No competing interests declared.
Journal
The American journal of cardiology, 2025
Source
PubMed record 40816671. This page is based on the abstract only.

How much this study counts

  • –Shows a link, not a cause: people chose their own habits, and other differences between them may explain the result.
  • ✓Followed people over time, so habits were recorded before the outcome happened.
  • ✓Large: 13,078 people.
  • ✓Measured the question itself: death, heart disease and other health outcomes.
  • ✓No competing interests declared.
  • •Summarized from the PubMed abstract only. The full paper may hold details the abstract leaves out.

✓ Strength– Limit• Note

These points come from fixed rules about the type of study, its size and length, what it measured, and who has a stake. Every study on Digestery gets the same rules.

Where this study sits

Each dot is one on-topic paper on this question. Steps near the top answer the question more directly.

↑ Stronger evidence

  1. Trials in people: death and chronic disease

    0

    Not done yet. This is the step that would answer the question.

  2. Trials in people: other measures

    1

    1 benefit

  3. Trials in people: lab tests or safety

    0

    None among the papers we read.

  4. Population studies

    11

    5 benefit, 4 mixed, 2 no difference

    ↑ This study is the ringed dot

  5. Blood levels and genes

    1

    1 benefit

↓ Weaker evidence

  • Points to benefit
  • Mixed
  • No difference
  • No direction
  • Points to harm

How it fits with the other research

The short answer to “How much sleep do adults need for good health?”

Lowest risk at about 7 hours.

Confidence: low. Based on 22 on-topic papers.

Read the full answer

Of the other 10 papers on the same step: 4 benefit, 4 mixed, 2 no difference. This one found benefit.

Other papers on the same step

See all 22 studies on this question

How this page was made

Label

First read of the abstract
Claude Sonnet
Independent second read
Claude Haiku
Differences settled
The two reads differed. The reviewer checked the abstract and kept the first read. Claude Opus 5.5.
Headline
Claude Sonnet, from the checked study record. A script checked its numbers and wording.
Numbers
Checked against the abstract by a script
“How much this study counts”
Fixed rules, the same for every study
Source check by a person
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