Clinical Report: The Relationship Between Thyroid Function and Sepsis Risk

Overview

This study investigates the association between thyroid-stimulating hormone (TSH) levels and the risk of sepsis and severe infectious diseases. TSH levels below 0.5 mU/L are associated with increased sepsis risk.

Background

Thyroid dysfunction affects a significant portion of the global population and is linked to immune system modulation. Understanding the relationship between thyroid function and infection risk is crucial, as infections can lead to severe outcomes like sepsis. Previous studies have shown mixed results regarding thyroid hormone levels and infection risk.

Data Highlights

No significant association was found between baseline normal-range TSH and sepsis risk in observational analyses of 45,364 subjects. TSH levels <0.5 mU/L were associated with a higher sepsis risk (HR 1.50, 95% CI 1.19–1.90). Mendelian randomization analyses involving 271,040 subjects showed no association between normal-range TSH and sepsis risk (OR 1.04, 95% CI 0.98–1.10).

Key Findings

• No association between baseline normal-range TSH and sepsis risk (HR 0.98, 95% CI 0.93–1.04).
• TSH levels <0.5 mU/L associated with higher sepsis risk (HR 1.50, 95% CI 1.19–1.90).
• Mendelian randomization analyses showed no link between normal-range TSH and sepsis risk (OR 1.04, 95% CI 0.98–1.10).
• Secondary analyses indicated no association between thyroid function and risk of lower respiratory tract infections or upper urinary tract infections.

Clinical Implications

Monitoring TSH levels within the normal range may not be beneficial for assessing sepsis risk.

Conclusion

Variations in thyroid function within the normal range do not causally influence the risk of sepsis or its common precursors.

Related Resources & Content

1. Frontiers in Endocrinology, 2026 -- Association of TyG index with sepsis incidence and mortality: a prospective study with diabetes stratification
2. The Journal of Clinical Endocrinology & Metabolism, 2023 -- Thyroid Activity and Overall Mortality in Relation to Multimorbidity: Findings from Two Population-Based Studies
3. The Journal of Clinical Endocrinology & Metabolism, 2023 -- Genetic Influences on Thyroid Activity: Implications for Biological Understanding and Clinical Treatment
4. Surviving Sepsis Campaign Adult Guidelines | SCCM, 2026
5. The Journal of Clinical Endocrinology & Metabolism — Assessing Cardiovascular Risk in Euthyroid Koreans: The Impact of the Parametric Thyroid Feedback Quantile Index
6. Causal association between thyroid dysfunction and sepsis: a two-sample mendelian randomization study
7. Thyroid function and risk of sepsis: A population-based prospective cohort study with traditional and genetic epidemiological analyses
8. Surviving Sepsis Campaign Adult Guidelines | SCCM
9. S3 guideline on sepsis—prevention, diagnosis, therapy, and follow-up care—update 2025 - PMC
10. [Causal relationship between thyroid dysfunction and sepsis: a bidirectional two-sample Mendelian randomization] - PubMed
11. Non-thyroidal illness syndrome subtypes and mortality in sepsis: associations with thyroid autoantibodies
12. Association between sensitivity to thyroid hormone and prognosis in septic patients: a retrospective cohort analysis
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14. Guidelines for the Treatment of Hypothyroidism: Prepared by the American Thyroid Association Task Force on Thyroid Hormone Replacement - PMC