Thyroid peroxidase antibody positivity is associated with symptomatic distress in patients with Hashimoto's thyroiditis.

Previous studies suggest impairments of physical, mental, and psychic well-being in patients with Hashimoto's thyroiditis (HT), but these impairments have been shown to be independent of thyroid dysfunction. In 64 euthyroid patients with HT, symptomatic distress was assessed with the Symptom Checklist-90-Revised (SCL-90-R), a 90-item multidimensional self-report symptom inventory using a 5-point rating scale. In a subgroup of patients, endocrine testing 3 years prior to the current investigation was available. Anti-thyroid peroxidase antibodies (TPO-Abs) were associated with the three SCL-90-R global indices Global Severity Index (GSI), Positive Symptom Distress Index (PSDI), and Positive Symptom Total (PST) as well as with somatization and obsessive-compulsive symptoms after adjustment for age, gender, and thyroid function as assessed by TSH levels (all p<0.05). HT patients positive for TPO-Abs showed poorer results in the three SCL-90-R global indices as well as in the three domains: somatization, obsessive-compulsive symptoms, and depression (all p≤0.02), though the aforementioned associations did not withstand sequential Bonferroni correction for multiple testing. In contrast, TPO-Abs positivity, defined as TPO-Abs >100 IU/l, significantly predicted poorer psychosocial well-being in all of the three SCL-90-R global indices after three years, even after correction (all p≤0.02). In conclusion, high TPO-Abs are associated with poor physical and psychological well-being and appear to predict future health perception in HT patients.