Patterns and persistence of use, effectiveness, safety, clinical inertia, and adherence related to Levothyroxine treatment with real-world evidence. An observational, longitudinal and retrospective study

TL;DR

This study examines how levothyroxine is used, its effectiveness, and adherence in Colombian patients with thyroid disease using real-world data.

Contribution

The study provides real-world evidence on levothyroxine treatment patterns and adherence in a Colombian patient cohort.

Findings

Only 47.7% of patients persisted with levothyroxine treatment after one year.

Clinical inertia and poor disease control were common despite few adverse events.

Older patients and those with comorbidities were more likely to persist with treatment.

Abstract

Over- and undertreatment of chronic diseases are common. In this context, real-world data on the use of levothyroxine are limited. The aim was to determine the patterns of use, persistence, effectiveness, safety, clinical inertia, and adherence related to levothyroxine treatment in a group of patients with thyroid disease in Colombia.

This was an observational study of patients treated with levothyroxine. Clinical records were reviewed, and the minimum patient follow-up was one year. Descriptive, bivariate and multivariate analyses were performed.

A total of 398 patients were identified; the median age was 53.5 years, and 71.1% were women. A total of 76.9% of the patients received levothyroxine for clinical hypothyroidism, and few adverse events occurred (4.3%). 52% of the patients were not on goal at their first thyroid-stimulating hormone (TSH) checkup. Only 36.4% had a second TSH control appointment, but among them, 65.1% did not reach their goals; moreover, 31.7% demonstrated clinical inertia. The medication possession ratio was 66.8% (≥ 80%: 31.4%), and 47.7% of the patients showed persistent use at one year. The presence of adverse events was associated with a lower probability of persistent use (OR:0.16; 95%CI:0.04–0.64).

Clinical inertia and poor disease control were common, whereas rates of adherence to and persistence with levothyroxine treatment were low. However, patients aged ≥ 40 years, those with a high educational level and chronic comorbidities, and those who habitually attended TSH control appointments were more likely to be persistent with their treatment at the one-year follow-up.

The online version contains supplementary material available at 10.1007/s12020-025-04488-1.

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