TSH abnormal refers to thyroid-stimulating hormone levels that fall outside the laboratory normal reference range, suggesting potential thyroid dysfunction. Elevated TSH usually indicates hypothyroidism, where the thyroid is underactive, while low TSH typically signals hyperthyroidism or excessive thyroid hormone replacement. TSH is often the most sensitive marker of thyroid status and is interpreted alongside free T4 and, in some cases, free T3 and thyroid antibodies. Persistent TSH abnormalities can be associated with cardiovascular risk, metabolic changes, and other health issues. For underwriting, TSH abnormalities require context regarding diagnosis, treatment, and stability to determine how they impact mortality and morbidity risk.

Underwriters review TSH abnormal findings when applicants report thyroid disease, fatigue, weight changes, or use thyroid medications. They look for a clear diagnosis, treatment plan, and follow-up labs showing that TSH and related hormones are trending toward or within target ranges. Mild, well-controlled hypothyroidism often receives favorable treatment, while uncontrolled hyperthyroidism or significant cardiac complications may lead to ratings or postponement. Advisors can improve outcomes by encouraging clients to bring recent lab work and physician notes at the time of application. Understanding TSH abnormal helps advisors explain why a seemingly minor lab deviation matters and how consistent management can support better health and underwriting results.