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Randomized trial · measured lab tests or safety

4-week trial in 54 people with heart failure: sauna raised heart pumping

Kuwahata and colleagues · Journal of cardiology · 2011

Original title: Improvement of autonomic nervous activity by Waon therapy in patients with chronic heart failure.

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

Among 27 sauna patients, cardiac output and ejection fraction rose after 4 weeks but did not change in 27 control patients. Heart rate variability moved toward calmer nerve activity only in the sauna group.

The study at a glance

Type of study
Randomized trial
Who or what was studied
54 people · people with chronic heart failure on usual treatment
What was tested
Waon therapy (dry sauna) plus usual treatment for 4 weeks, vs usual treatment alone
What it measured
Lab tests or markers
How long
4 weeks
Who has a stake
No disclosure in PubMed
No disclosure in PubMed.
Journal
Journal of cardiology, 2011
Source
PubMed record 20884178. This page is based on the abstract only.

How much this study counts

  • ✓Randomized: people were put into groups by chance, so the groups start out alike.
  • •Medium size: 54 people.
  • –Short: 4 weeks. Longer-term effects are unknown.
  • –Measured lab tests or markers, which stand in for heart disease, blood pressure and death. A better marker does not always mean better health.
  • •The PubMed record has no conflict-of-interest statement.
  • •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: heart disease, blood pressure and death

    3

    3 benefit

  2. Trials in people: other measures

    2

    1 benefit, 1 no difference

  3. Trials in people: lab tests or safety

    5

    2 benefit, 1 mixed, 2 no difference

    ↑ This study is the ringed dot

  4. Population studies

    4

    4 benefit

  5. Blood levels and genes

    0

    None among the papers we read.

↓ Weaker evidence

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

How it fits with the other research

The short answer to “Does sauna use lower heart disease risk?”

Possibly, but not proven in trials.

Confidence: low. Based on 21 on-topic papers.

Read the full answer

Of the other 4 papers on the same step: 1 benefit, 1 mixed, 2 no difference. This one found benefit.

Other papers on the same step

See all 21 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 reviewer corrected 2 fields after reading the abstract. 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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