TY - JOUR
T1 - Thyrotropin receptor antibodies in early pregnancy
AU - Torp, Nanna Maria Uldall
AU - Bruun, Niels Henrik
AU - Christensen, Peter Astrup
AU - Handberg, Aase
AU - Andersen, Stig
AU - Andersen, Stine Linding
PY - 2022/9
Y1 - 2022/9
N2 - CONTEXT: Thyrotropin (TSH) receptor antibodies (TRAb) are important when distinguishing between Graves' and gestational hyperthyroidism, but sparse evidence exists on the recommended cutoff during pregnancy. OBJECTIVE: This work aimed to establish a method- and pregnancy-specific cutoff for TRAb, to describe the frequency of TRAb positivity in early pregnancy, and to follow up the women in the years after pregnancy. METHODS: This cohort study used the North Denmark Region Pregnancy Cohort and Danish nationwide registers of women in the North Denmark Region who had a blood sample drawn in early pregnancy, 2011 to 2015, that was stored in a biobank for assessment of thyroid function and thyroid autoantibodies. A cutoff value for TRAb was established in a reference cohort (n = 524) and used to identify TRAb-positive and TRAb-negative hyperthyroidism in early pregnancy for evaluation of frequency and follow-up. RESULTS: The method- and cohort-specific cutoff for TRAb in early pregnancy was 0.98 IU/L (95% CI, 0.96-0.99 IU/L). Among women with low TSH in early pregnancy and no known thyroid disease (n = 414), 21 women (5.1%) were TRAb positive and 393 (94.9%) were TRAb negative. Follow-up in the years following the pregnancy (median 8.1 years) revealed that 52.4% of women with TRAb-positive hyperthyroidism and 8.4% of the women with TRAb-negative hyperthyroidism were diagnosed with hyperthyroidism. CONCLUSION: This is the first study to measure TRAb in a large group of women in early pregnancy and to establish a pregnancy-specific cutoff. Results reveal that TRAb-negative hyperthyroidism is predominant in early pregnancy and rarely associated with later development of hyperthyroidism.
AB - CONTEXT: Thyrotropin (TSH) receptor antibodies (TRAb) are important when distinguishing between Graves' and gestational hyperthyroidism, but sparse evidence exists on the recommended cutoff during pregnancy. OBJECTIVE: This work aimed to establish a method- and pregnancy-specific cutoff for TRAb, to describe the frequency of TRAb positivity in early pregnancy, and to follow up the women in the years after pregnancy. METHODS: This cohort study used the North Denmark Region Pregnancy Cohort and Danish nationwide registers of women in the North Denmark Region who had a blood sample drawn in early pregnancy, 2011 to 2015, that was stored in a biobank for assessment of thyroid function and thyroid autoantibodies. A cutoff value for TRAb was established in a reference cohort (n = 524) and used to identify TRAb-positive and TRAb-negative hyperthyroidism in early pregnancy for evaluation of frequency and follow-up. RESULTS: The method- and cohort-specific cutoff for TRAb in early pregnancy was 0.98 IU/L (95% CI, 0.96-0.99 IU/L). Among women with low TSH in early pregnancy and no known thyroid disease (n = 414), 21 women (5.1%) were TRAb positive and 393 (94.9%) were TRAb negative. Follow-up in the years following the pregnancy (median 8.1 years) revealed that 52.4% of women with TRAb-positive hyperthyroidism and 8.4% of the women with TRAb-negative hyperthyroidism were diagnosed with hyperthyroidism. CONCLUSION: This is the first study to measure TRAb in a large group of women in early pregnancy and to establish a pregnancy-specific cutoff. Results reveal that TRAb-negative hyperthyroidism is predominant in early pregnancy and rarely associated with later development of hyperthyroidism.
KW - Graves’ disease
KW - TRAb
KW - TSH
KW - hyperthyroidism
KW - thyroid disease
UR - http://www.scopus.com/inward/record.url?scp=85136911091&partnerID=8YFLogxK
U2 - 10.1210/clinem/dgac383
DO - 10.1210/clinem/dgac383
M3 - Journal article
SN - 0021-972X
VL - 107
SP - e3705-e3713
JO - The Journal of clinical endocrinology and metabolism
JF - The Journal of clinical endocrinology and metabolism
IS - 9
M1 - dgac383
ER -