SUN-256 Is Thyroid Antibody Testing Useful to Predict the Risk of Coronary Heart Disease and Stroke Independently of Thyroid Function? An Individual Participant Data Analysis.

Abstract Disclosure: O. Hysaj: None. O. Efthimiou: None. T. Collet: None. A.R. Cappola: None. F. Azizi: None. A. Köttgen: None. E. Selvin: None. L. Chacker: None. R. P. Peeters: None. S. Trompet: None. J. Gussekloo: None. J. Walsh: None. S. Brown: None. M. Iacoviello: None. D. Robin P.F.: None. B. Stephan J.L.: None. C. Del Giovane: None. N. Rodondi: None. Introduction: A positive test for peroxidase antibody (TPOAb) is present in 35–65% of individuals with subclinical hypothyroidism and predicts progression to overt hypothyroidism. While both subclinical and overt hypothyroidism increase cardiovascular risk, the role of TPOAb in predicting coronary heart disease (CHD) and stroke independently of thyroid function remains unclear. Methods: We identified studies through Thyroid Studies Collaboration (TSC). Additionally, we searched MEDLINE, EMBASE, and Cochrane Library databases from inception until July 2024 for eligible prospective studies reporting baseline thyroid function, TPOAb, and any of the following outcomes: CHD events, CHD mortality, stroke events, and stroke mortality. We used Cox proportional hazards models, adjusted for age, sex, and thyroid-stimulating hormone (TSH) within each cohort, followed by a random-effects meta-analysis to examine cardiovascular outcomes by TPOAb status, overall and comparing individuals with subclinical hypothyroidism to euthyroid individuals. Additional adjustments included smoking status, body mass index (BMI), systolic blood pressure, diabetes status, and total cholesterol. Results: Among 100,250 adults from 14 cohort studies (median age 55 years, 56.7% women), 11.9% were TPOAb-positive, and 5.4% had subclinical hypothyroidism (of whom 41.6% were TPOAb-positive). We found no evidence of a risk difference between participants with positive vs. negative TPOAb in the overall population: HR 1.00 (95% CI 0.90-1.11) for CHD events; HR 0.95 (95% CI 0.78-1.16) for CHD mortality; HR 0.98 (95% CI 0.87-1.11) for stroke events; and HR 1.06 (95% CI 0.81–1.40) for stroke mortality. Comparing TPOAb-positive subclinical hypothyroidism to euthyroid individuals yielded no risk differences for CHD or stroke outcomes. Among participants with subclinical hypothyroidism, positive vs. negative TPOAb HRs were 0.87 (95% CI 0.72 to 1.05) for CHD events, 0.88 (95% CI 0.64 to 1.21) for CHD mortality, 0.68 (95% CI 0.51 to 0.90) for stroke events, and 0.93 (95% CI 0.51 to 1.90) for stroke mortality. Conclusion: Positive TPOAb does not predict CHD or stroke risk independently of thyroid function. These findings suggest that TPOAb testing is not useful for cardiovascular risk stratification in euthyroid individuals or those with subclinical hypothyroidism. Presentation: Sunday, July 13, 2025