The Claim

Thyroid hormone under-replacement, defined as TSH >5.5 mIU/L, is associated with a 24% increased risk of incident heart failure per year of exposure, with each incremental rise in TSH above 5.5 mIU/L further increasing this risk, indicating a graded relationship between thyroid hormone deficiency and cardiac strain.

Source: Association between Over- and Under-Replacement with Thyroid Hormone and Incident Heart Failure

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
59score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Correlation
1 study reviewed
In plain English

People with consistently elevated TSH levels above 5.5 mIU/L due to insufficient thyroid hormone replacement have a higher risk of developing heart failure over time, and the risk increases further as TSH levels rise above that threshold.

See the scientific wording

Thyroid hormone under-replacement, defined as TSH >5.5 mIU/L, is associated with a 24% increased risk of incident heart failure per year of exposure, and this association is dose-dependent, with each incremental rise in TSH above 5.5 mIU/L further increasing risk, suggesting a graded relationship between thyroid hormone deficiency and cardiac strain.

What the research says

1 study
  1. Study: Association between Over- and Under-Replacement with Thyroid Hormone and Incident Heart Failure

    When people don't get enough thyroid hormone medicine, their TSH levels go up, and this study shows that the higher TSH goes, the more likely they are to develop heart failure over time. It's like too little thyroid hormone puts extra strain on the heart.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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