ICD-10 Code for Family History of Hypothyroidism
The ICD-10 code for a family member having hypothyroidism is Z83.49 (Family history of other endocrine, nutritional and metabolic diseases). 1, 2
Primary Code Selection
- Z83.49 is the appropriate code when documenting that a patient has a family member (first-degree relative such as parent, sibling, or child) with hypothyroidism 1, 2
- This code falls under the broader category of "Family history of other conditions" and specifically addresses endocrine disorders including thyroid disease 1
Clinical Significance of Family History
- Having a first-degree relative with hypothyroidism significantly increases an individual's risk of developing the condition themselves, making this family history documentation clinically relevant 1, 2
- The genetic predisposition is particularly strong for autoimmune thyroid disease (Hashimoto's thyroiditis), which accounts for up to 85% of hypothyroidism cases in iodine-sufficient areas 1, 2
- Relatives of patients with Hashimoto's thyroiditis have a 4.3% annual progression risk to overt hypothyroidism if they have positive thyroid antibodies, compared to 2.6% in antibody-negative individuals 3
When to Use This Code
- Use Z83.49 when the family history of hypothyroidism is relevant to the patient's current evaluation, risk assessment, or screening decisions 3, 1
- This code is appropriate for documenting family history during preventive care visits or when evaluating patients with symptoms suggestive of thyroid dysfunction 3, 2
- The code supports medical necessity for thyroid screening in high-risk individuals, as targeted testing is recommended for patients with first-degree relatives who have hypothyroidism 1, 4
Screening Recommendations for At-Risk Family Members
- Measure TSH as the primary screening test, which has 98% sensitivity and 92% specificity for detecting thyroid dysfunction 3, 4
- Repeat thyroid function screening every 5 years in asymptomatic relatives with normal initial results 3
- Consider annual screening for relatives with positive thyroid antibodies but normal TSH, given their elevated progression risk 3
- TSH values above 6.5 mU/L warrant further evaluation, and values above 10 mU/L indicate need for treatment regardless of symptoms 3, 5