Endocrine Abstracts

JOINT3926

Subclinical hypothyroidism ( SCH) is most often diagnosed incidentally, and raises the question of the treatment indication. The aim of this study was to describe the progressive profile of sch and to identify the factors associated with the absence of spontaneous normalization of the thyroid function.

Methods: Longitudinal study of a retrospective cohort of 69 patients with SCH defined by normal FT4 and TSH > 4mUI/l. Patients were subdivided into two groups according to the spontaneous normalization or non-normalization of thyroid function during follow-up.

Results: The study population was composed of 57 women and 12 men, of mean age of 42.3 ± 15.8 years. After a mean follow-up time of 19,6 ± 15.1 months, thyroid function normalized spontaneously in 18 patients (26% of cases). the mean time to normalization of thyroid function was 9,8 ± 4,2 months. Absence of spontaneous normalization of thyroid function was inversely correlated with FT4 level P = 0.04). ATPO positivity was statistically different between groups (P = 0.01). ATPO levels were significantly higher in the absence of spontaneous normalization of thyroid function (589.7 ± 607.7 IU/l vs. 112.1 ± 54.8 IU/l, P = 0.01) and was associated with high prevalence of evolution to an overt hyperthyroidism. TSH level was non-statistically different ( P = 0.2). Age, gender, presence of symptoms of hypothyroidism and presence of goiter on cervical ultrasonography were not associated with the progression of the SCH in our study

Discussion and Conclusion: Spontaneous normalization of thyroid function was observed in almost a quarter of patients with SCH. A lower FT4 rate, the positivity of ATPO were associated with absence of spontaneous normalization of thyroid function. A Higher rate of ATPO was associated with progression to overt hypothyroidism requiring close monitoring in these patients