Screening for thyroid disease at the menopausal clinic
Faughnan, M.; Lepage, R.; Fugère, P.; Bissonnette, F.; Brossard, J.H.; D'Amour, P.
Clinical and Investigative Medicine 18(1): 11-18
1995
ISSN/ISBN: 0147-958X PMID: 7768061 Document Number: 449462
The prevalence of hypothyroidism has been reported to increase with age and to attain up to 10% in older women. We wanted to verify whether routine screening for thyroid disease could be justified in a specific sub-population of aging women, those consulting for the first time at a menopausal clinic. Standard thyroid profiles (Total T4, T3 uptake, calculated free thyroxine index (FTI), and sensitive thyroid stimulating hormone (TSH)) were obtained in 500 consecutive patients seen at such a clinic over 18 months. Thyroid microsomal and thyroglobulin antibody titers were also obtained in over half of them. Twenty-three carefully selected, age-matched, peri-menopausal hospital employees served as a reference group for the TRH response test. Thirteen women (2.6%) had previously diagnosed hypothyroidism but 4 of them were found to be sub-optimally treated. Fifty other subjects (10%) had out-of-range screening TSH levels, 7 below and 43 over the assay reference range. In the former, 3 (0.6%) were found to be hyperthyroid while in the latter 8 (1.6%) were found to be overtly hypothyroid based on TSH levels over 10 mU/L and accompanying signs and symptoms. Twelve other subjects (2.4%) were found to have sub-clinical hypothyroidism based on a positive TRH response test and a significantly increased prevalence of goiter and positive antibody titers. The remaining 23 patients had a normal TRH response test, although their mean TSH level at 30-min post-TRH and the prevalence of positive antibody titers were significantly higher than those of the control group and normal subjects respectively. Based on the observed overall prevalence of 7.2% of thyroid disease (6.6% of hypothyroidism) and on the detection of 4.6% of new cases of thyroid dysfunction (half of them with overt disease), this study suggests that screening for thyroid disease is justified in women consulting for the first time for menopausal symptoms. Our data also indicate that TSH alone should be sufficient as a screening tool if carefully determined reference values are used.