Cardiovascular Risk Prediction in Hypothyroidism: What Current Models Capture and Miss—A Narrative Review

Background and Objectives: Hypothyroidism can alter lipid metabolism, vascular resistance, body composition, and myocardial function. Yet the cardiovascular risk engines used in routine practice were developed in general populations and do not include thyroid status. This review examines what contemporary risk models capture, what they omit, and how thyroid dysfunction should influence interpretation without being treated as an unvalidated numerical correction. Materials and Methods: A focused narrative search of PubMed was performed for publications from January 2014 through 6 September 2026, supplemented by earlier landmark cohort studies, risk-model derivation papers, randomized trials, and professional guidelines. Evidence was organized around overt and subclinical hypothyroidism, traditional risk factors, observed cardiovascular events, and the design and validation of major risk equations. Results: SCORE2, SCORE2-OP, Framingham, QRISK3, and PREVENT differ in predicted outcomes, age ranges, geography, and required inputs; their percentages and categories are therefore not interchangeable. Thyroid status is absent from these engines. A prospective community cohort found that adding TSH produced little incremental discrimination beyond conventional scores, whereas cross-sectional studies sometimes found higher calculated risk in women with subclinical hypothyroidism. Individual-participant data suggest that excess coronary and heart-failure risk is concentrated at higher TSH levels, while a large 2025 pooled analysis found only small differences in conventional risk factors between subclinical thyroid dysfunction and euthyroidism. Levothyroxine improves lipids most clearly in overt hypothyroidism, but cardiovascular outcome benefit in older adults with mild subclinical disease remains unproven. Conclusions: Clinicians should use one validated, region- and age-appropriate cardiovascular model, confirm that the patient meets its intended-use criteria, and evaluate thyroid disease in parallel. Cross-model percentage comparisons should be avoided. Persistent TSH elevation, overt hormone deficiency, treatment status, frailty, and severe dyslipidemia belong in clinical judgment and follow-up, not in an improvised score multiplier.