FRI528 Trends And Components Of Thyroid Status Evaluation In Commercially Insured Adults In The US, 2006-2020
Authors: Morris Earl J , Singh Ospina Naykky Maruquel , Maraka Spyridoula , Vouri Scott M 
Published: October 2023

Disclosure: E.J. Morris: None. N.M. Singh Ospina: None. S. Maraka: None. S.M. Vouri: Employee; Self; Pfizer, Inc.

Background. In clinical practice, evaluation of thyroid function can be used to monitor patients with thyroid dysfunction, to clarify the etiology of a patient’s symptom, or as screening. Although studies suggest variability and possibly overuse of TSH testing, no contemporary assessment of TSH testing trends and components of thyroid testing are available. Methods. We conducted a longitudinal assessment of commercially insured adults to characterize thyroid function testing among patients without pre-existing thyroid disease. We identified all adults 18-64 years old with at least 365 days of continuous enrollment between January 1, 2006 to July 31, 2020 using IBM MarketScan Commercial Claims Databases. This nationwide administrative claims database contains beneficiary-level clinical information related to diagnoses, procedures, and prescriptions. To identify patients without or at high risk for thyroid disease we excluded those with evidence of medication use for treatment of thyroid dysfunction or interfering with thyroid function, diagnosis of thyroid disease, or pregnancy. Descriptive statistics were used to summarize relevant characteristics of patients undergoing TSH testing, TSH tests per 1,000 eligible person-months, and composition of thyroid function testing. Results. Among 67,353,280 patients meeting eligibility criteria, we identified 25,606,518 TSH tests and 15,138,211 patients with ≥ 1 TSH test. Patients contributing an episode of TSH testing were most commonly 45-54 years old (29.8%) and female (63.6%). Dyslipidemia (34.2%) and fatigue (21.4%) were the most common associated comorbidities. TSH testing rates remained relatively consistent throughout the study period with 11.4 and 11.7 TSH tests per 1,000 person-months in the first and last study months, respectively. Among all study months, we observed a mean of 12.2 TSH tests per 1,000 person-months. TSH testing rates dropped sharply in the spring of 2020 (4.2 TSH tests per 1,000 person-months). Females showed a nearly twofold higher rate of TSH testing compared to males (16.1 TSH tests per 1,000 person-months vs. 8.6 TSH tests). TSH testing rates increased consistently with age (8.2 TSH tests per 1,000 person-months among individuals 18-34 years old vs. 15.4 TSH tests among individuals 55-64 years old). The evaluation of thyroid function was completed only with TSH in most episodes (70.8%), followed by combination of TSH and FT4 testing (14.8%). Evaluation of thyroid autoimmunity was included in 2.7% of testing episodes. Panels including RT3, THBR or Tg represented 4.5% of the episodes. Conclusion. TSH testing frequency among commercially insured individuals without thyroid disease appears stable, with higher frequency found in females and with increasing age. Testing most commonly includes only TSH. The appropriateness of thyroid function evaluation will require further investigation.

Presentation: Friday, June 16, 2023