[Prevalence of thyroid abnormality: a comparison of ambulatory claims data with data from a population-based study]

Trends in the use of thyroid diagnostics and treatments between 2008 and 2019 in Germany

Following implementation of a national prevention program against iodine deficiency-related disorders in 1993 in Germany, the prevalence of thyroid disorders declined, but aggregated drug dispensation data suggested a recent increase in thyroid hormone use. We aimed to systematically investigate trends in the use of thyroid diagnostic and treatment measures between 2008 and 2019 in Germany. Using the GePaRD database (claims data from ~ 20% of the German population), we determined the annual age-specific and age-standardized prevalence of the use of thyroid diagnostics (thyroid-stimulating hormone (TSH) measurement, thyroid ultrasound, scintiscan, biopsy) and treatment (medication, surgery, radioiodine therapy) from 2008 to 2019 stratified by sex. Between 2008 and 2019, the age-standardized prevalence of TSH measurement increased by 44% in males (from 165 to 238 per 1,000 persons) and by 31% in females (from 134 to 176 per 1,000). The prevalence of thyroid ultrasound use showed no clear time trend, while there was a decrease in the prevalence of scintiscan use (males/females: decrease by 42/43%) and biopsy (males/females: decrease by 42/34%). The prevalence of levothyroxine use increased by ~ 31% both in males (from 36 to 47 per 1,000) and females (from 134 to 175 per 1,000), while the prevalence of thionamide use, iodine use, thyroidectomy, and radioiodine therapy decreased. Our study suggests a continued decline in the prevalence of clinically significant thyroid disorders between 2008 and 2019. The substantial increase in the prevalence of TSH measurement and levothyroxine use during this time period might indicate overuse of diagnostics and overtreatment, warranting further investigation.

Malignancy rates in thyroid nodules: a long-term cohort study of 17,592 patients

Objectives

Ultrasound diagnosis of thyroid nodules has greatly increased their detection rate. Their risk for malignancy is estimated between 7 and 15% in data from specialized centers which are used for guidelines recommendations. This high rate causes considerable anxiety to patients upon first diagnosis. Here, we retrospectively analyzed the malignancy rate of sonographically diagnosed nodules larger than 1 cm from a primary/secondary care center when long-term longitudinal follow-up was included.

Patients/methods

In the study, 17,592 patients were diagnosed with a thyroid nodule larger than 1 cm, of whom 7776 were assessed by fine-needle aspiration cytology (FNAC) and 9816 by sonography alone. 9568 patients were initially discharged due to innocent results of FNAC and/or ultrasound. In 1904 patients, definitive histology was obtained, and 6731 cases were included in the long-term follow-up (up to 23 years, median 5 years).

Results

Malignancy was histologically confirmed in 189 patients (1.1% of all) when excluding accidentally diagnosed papillary microcarcinomas. 155 were diagnosed during the first year of management, 25 in years 2-5 of follow-up, 9 in years 6-10 and nil in 1165 patients followed beyond 10 years.

Conclusions

The malignancy rate of thyroid nodules from primary/secondary care was much lower than that previously reported. During follow-up for more than 5 years, their rate rapidly dropped to less than 1/1000 cases. This low malignancy rate may help to reassure patients first confronted with the diagnosis of a thyroid nodule, substantially reduce their anxiety and avoid unwarranted diagnostic and therapeutic procedures.

Frequency of thyroid function tests and examinations in participants of a population-based study

BACKGROUND

Thyroid disorders are common in the adult German population. Little is known about guideline implementation in clinical practice and the prevalence of diagnostic procedures in ambulatory care. The study aims to investigate the use of thyroid hormone measurements, thyroid ultrasound, thyroid scintiscan and associated costs in ambulatory care at population level.

METHODS

Data were derived from two independent population-based cohorts of the Study of Health In Pomerania (SHIP). Ambulatory billing data from the Association of Statutory Health Insurance Physicians Mecklenburg-Vorpommern were individually linked for the period 2002-2016 with SHIP data. The main outcomes were the frequency of outpatient ultrasound, scintiscan, serum TSH level measurement, free triiodothyronine (fT3) and free thyroxine (fT4) measurement, TSH-receptor-antibodies and microsomal antibodies measurement within 1 year and 3 years prior to the study entrance of the participants. Multinomial logistic regression models were used to assess the association of age, sex, thyroid medication intake and Charlson-Comorbidity-Index with frequency of TSH measurements and ultrasound examinations.

RESULTS

A total of 5552 participants (47% male, median age 55) were included in the analysis. 25% (1409/5552) had a diagnosed thyroid disorder or treatment, 40% (2191/5552) had clinical findings based on ultrasound or laboratory testing in SHIP only and 35% (1952/5552) neither a coded thyroid disorder or clinical finding nor thyroid medication. In the total study population 30% (1626/5552) received at least one TSH measurement, 6.8% (378/5552) at least one thyroid ultrasound and 2.6% (146/5552) at least one scintiscan within the past year before the study examination. Tests were performed more frequently in patients with thyroid medication and coded thyroid disorders. Hence, this group caused the highest expenditures.

CONCLUSIONS

Given the high prevalence of thyroid disorders, diagnostic and monitoring tests should be used rationally with regard to costs. TSH levels should be monitored regularly in patients on thyroid medication. A consensus on monitoring frequency and iteration of monitoring of morphological thyroid disorders with TSH and ultrasound and specific guideline recommendations are needed.

TRIAL REGISTRATION

Versorgungsforschung Deutschland (VfD_17_003880).