TY - JOUR
T1 - The Prevalence of Thyroid Dysfunction and Autoimmunity in Women With History of Miscarriage or Subfertility
AU - Dhillon-Smith, R.K.
AU - Tobias, A.
AU - Smith, P.P.
AU - Middleton, L.J.
AU - Sunner, K.K.
AU - Baker, K.
AU - Farrell-Carver, S.
AU - Bender-Atik, R.
AU - Agrawal, R.
AU - Bhatia, K.
AU - Chu, J.J.
AU - Edi-Osagie, E.
AU - Ewies, A.
AU - Ghobara, T.
AU - Gupta, P.
AU - Jurkovic, D.
AU - Khalaf, Y.
AU - Mulbagal, K.
AU - Nunes, N.
AU - Overton, C.
AU - Quenby, S.
AU - Rai, R.
AU - Raine-Fenning, N.
AU - Robinson, L.
AU - Ross, J.
AU - Sizer, A.
AU - Small, R.
AU - Underwood, M.
AU - Kilby, M.D.
AU - Daniels, J.
AU - Thangaratinam, S.
AU - Chan, S.
AU - Boelaert, K.
AU - Coomarasamy, A.
N1 - cited By 1
PY - 2020/8/1
Y1 - 2020/8/1
N2 - OBJECTIVE: To describe the prevalence of and factors associated with different thyroid dysfunction phenotypes in women who are asymptomatic preconception. DESIGN: Observational cohort study. SETTING: A total of 49 hospitals across the United Kingdom between 2011 and 2016. PARTICIPANTS: Women aged 16 to 41years with history of miscarriage or subfertility trying for a pregnancy. METHODS: Prevalences and 95% confidence intervals (CIs) were estimated using the binomial exact method. Multivariate logistic regression analyses were conducted to identify risk factors for thyroid disease.None. MAIN OUTCOME MEASURE: Rates of thyroid dysfunction. RESULTS: Thyroid function and thyroid peroxidase antibody (TPOAb) data were available for 19213 and 19237 women, respectively. The prevalence of abnormal thyroid function was 4.8% (95% CI, 4.5-5.1); euthyroidism was defined as levels of thyroid-stimulating hormone (TSH) of 0.44 to 4.50 mIU/L and free thyroxine (fT4) of 10 to 21 pmol/L. Overt hypothyroidism (TSH > 4.50 mIU/L, fT4 < 10 pmol/L) was present in 0.2% of women (95% CI, 0.1-0.3) and overt hyperthyroidism (TSH < 0.44 mIU/L, fT4 > 21 pmol/L) was present in 0.3% (95% CI, 0.2-0.3). The prevalence of subclinical hypothyroidism (SCH) using an upper TSH concentration of 4.50 mIU/L was 2.4% (95% CI, 2.1-2.6). Lowering the upper TSH to 2.50 mIU/L resulted in higher rates of SCH, 19.9% (95% CI, 19.3-20.5). Multiple regression analyses showed increased odds of SCH (TSH > 4.50 mIU/L) with body mass index (BMI) ≥ 35.0 kg/m2 (adjusted odds ratio [aOR] 1.71; 95% CI, 1.13-2.57; P = 0.01) and Asian ethnicity (aOR 1.76; 95% CI, 1.31-2.37; P < 0.001), and increased odds of SCH (TSH ≥ 2.50 mIU/L) with subfertility (aOR 1.16; 95% CI, 1.04-1.29; P = 0.008). TPOAb positivity was prevalent in 9.5% of women (95% CI, 9.1-9.9). CONCLUSIONS: The prevalence of undiagnosed overt thyroid disease is low. SCH and TPOAb are common, particularly in women with higher BMI or of Asian ethnicity. A TSH cutoff of 2.50 mIU/L to define SCH results in a significant proportion of women potentially requiring levothyroxine treatment.
AB - OBJECTIVE: To describe the prevalence of and factors associated with different thyroid dysfunction phenotypes in women who are asymptomatic preconception. DESIGN: Observational cohort study. SETTING: A total of 49 hospitals across the United Kingdom between 2011 and 2016. PARTICIPANTS: Women aged 16 to 41years with history of miscarriage or subfertility trying for a pregnancy. METHODS: Prevalences and 95% confidence intervals (CIs) were estimated using the binomial exact method. Multivariate logistic regression analyses were conducted to identify risk factors for thyroid disease.None. MAIN OUTCOME MEASURE: Rates of thyroid dysfunction. RESULTS: Thyroid function and thyroid peroxidase antibody (TPOAb) data were available for 19213 and 19237 women, respectively. The prevalence of abnormal thyroid function was 4.8% (95% CI, 4.5-5.1); euthyroidism was defined as levels of thyroid-stimulating hormone (TSH) of 0.44 to 4.50 mIU/L and free thyroxine (fT4) of 10 to 21 pmol/L. Overt hypothyroidism (TSH > 4.50 mIU/L, fT4 < 10 pmol/L) was present in 0.2% of women (95% CI, 0.1-0.3) and overt hyperthyroidism (TSH < 0.44 mIU/L, fT4 > 21 pmol/L) was present in 0.3% (95% CI, 0.2-0.3). The prevalence of subclinical hypothyroidism (SCH) using an upper TSH concentration of 4.50 mIU/L was 2.4% (95% CI, 2.1-2.6). Lowering the upper TSH to 2.50 mIU/L resulted in higher rates of SCH, 19.9% (95% CI, 19.3-20.5). Multiple regression analyses showed increased odds of SCH (TSH > 4.50 mIU/L) with body mass index (BMI) ≥ 35.0 kg/m2 (adjusted odds ratio [aOR] 1.71; 95% CI, 1.13-2.57; P = 0.01) and Asian ethnicity (aOR 1.76; 95% CI, 1.31-2.37; P < 0.001), and increased odds of SCH (TSH ≥ 2.50 mIU/L) with subfertility (aOR 1.16; 95% CI, 1.04-1.29; P = 0.008). TPOAb positivity was prevalent in 9.5% of women (95% CI, 9.1-9.9). CONCLUSIONS: The prevalence of undiagnosed overt thyroid disease is low. SCH and TPOAb are common, particularly in women with higher BMI or of Asian ethnicity. A TSH cutoff of 2.50 mIU/L to define SCH results in a significant proportion of women potentially requiring levothyroxine treatment.
KW - miscarriage
KW - preconception
KW - prevalence
KW - subfertility
KW - thyroid autoimmunity
KW - thyroid disease
UR - http://www.scopus.com/inward/record.url?scp=85087320491&partnerID=8YFLogxK
U2 - 10.1210/clinem/dgaa302
DO - 10.1210/clinem/dgaa302
M3 - Article
SN - 0021-972X
VL - 105
JO - The Journal of clinical endocrinology and metabolism
JF - The Journal of clinical endocrinology and metabolism
IS - 8
ER -
