Review of the natural course of subclinical hypothyroidism and study of its costs

Abstract Introduction Subclinical hypothyroidism is defined as elevation of thyroid-stimulating hormone (TSH) levels, with normal thyroid hormone levels and negative autoimmunity, in asymptomatic patients with no findings on examination. Because of the unwarranted increase in thyroid function tests in asymptomatic children, the main objective of this review was to analyze the course of these patients. Analysis of associated costs was a secondary objective. Material and methods A longitudinal, observational, retrospective study of patients referred to the endocrinology department of a tertiary hospital for high TSH levels (TSH 5–20 mIU/l). Clinical and laboratory variables, number of visits until discharge, need for treatment, monitoring time, and economic variables were collected. Results The study sample consisted of 155 patients with a mean age of 7.8 years ± 3.6 SD. Referrals to endocrinology accounted for 4% of first office visits. Baseline mean TSH level was 7.8 mU/l (5.03–15.8 mU/l). TSH levels normalized after the first repeated measurement during the subsequent month in 60% of cases. A total of 83.6% of patients were discharged within a maximum of 3 years, with a mean follow-up of 8.14 ± 6.8 months and 2.4 visits/patient. Average cost per patient was € 251.27 (range € 143.49–444.21). Conclusion It is essential not to alarm the family when subclinical hypothyroidism is detected, because this is a biochemical situation which normalizes in most cases. This fact, together with the mean cost of specialized care, suggests that the first step should be repeated TSH measurements in primary care.