Forgotten drugs: long-term prescriptions of thyroid hormones - a cross-sectional study

Thyroid hormones are among the most prescribed drugs in Germany. Although iodine supply has been improving in the last decade, annual prescriptions for thyroid hormones are rising. The aim of this study was to provide prevalence of thyroid hormone prescribing and to explore reasons for thyroid hormone prescription in primary care settings.

A cross-sectional study.

Data collection took place in six general practitioner (GP) practices in Hesse, Germany. We used the records of six GP practices to estimate prevalence of thyroid hormone prescribing. All patients who received a prescription of the active ingredient levotyroxine during the preceding 3 months were mailed a study invitation. A proportion of the identified patients were interviewed. In addition, demographical data and all medical findings related to thyroid disease were recorded.

On average, 9.2% (SD 4.6) of all patients from participating practices were taking thyroid hormones. The majority were female (82.5%). In 47.7% of the study participants, the GP's diagnosis, according to their records, was nonexistent. In 13.6% of cases, the documentation of the diagnostic information was incomplete. While 25% of interviewed patients with high educational background initiated further diagnostic investigation, only 4.4% of the patients with lower education did so.

In the majority of patients treated with thyroid hormones, doctors had not documented the precise indication for prescription.