Is Thyroid Autoimmunity per se a Determinant of Quality of Life in Patients with Autoimmune Hypothyroidism?

Abstract

Purpose: To evaluate the relationship between thyroid variables and health-related quality of life (QoL) in patients with autoimmune hypothyroidism, using the thyroid-specific QoL questionnaire ThyPRO. Methods: In a cross-sectional study, responses to the ThyPRO from 199 outpatients with autoimmune hypothyroidism were analyzed in relation to thyroid volume, thyroid function and markers of thyroid autoimmunity. Based on a classical QoL framework, we hypothesized that physiological dysfunction caused specific physical and psychological symptoms, which affected functioning and well-being, and consequently participation in life and QoL. These hypotheses were tested through multiple regression and multivariate path analysis models. Results: None of the thyroid function tests were associated with QoL scores. However, in the pairwise regression, the thyroid peroxidase antibody (TPOAb) level was associated with several QoL outcomes: Goitre Symptoms (p = 0.024), Depressivity (p = 0.004), Anxiety (p = 0.004), Emotional Susceptibility (p = 0.005) and Impaired Social Life (p = 0.047). In the multivariate model, the TPOAb level was related to Goitre Symptoms (r = 0.17, p = 0.019), Depressivity (r = 0.24, p = 0.001), and Anxiety (r = 0.23, p = 0.002), but no longer to Emotional Susceptibility or Impaired Social Life, indicating that the effect on these were mediated through an effect on the symptom scales (i.e. Goitre Symptoms, Depressivity and Anxiety). Conclusion: Health-related QoL, evaluated with state-of-the-art QoL methodology, was related to TPOAb level but not to thyroid function. This raises the hypothesis that autoimmunity, independent of thyroid function, impacts on QoL in patients with autoimmune hypothyroidism, especially in terms of psychological symptoms. Longitudinal studies, in initially untreated patients, are needed to test this hypothesis.

Development of a Short Version of the Thyroid-Related Patient-Reported Outcome ThyPRO

“…Based on knowledge about the ThyPRO instrument, and on the IRT-derived item information functions (29), the best items were selected. Knowledge about ThyPRO stemmed from the initial qualitative content validation studies (14,15) and from other validation studies evaluating cross-cultural invalidity (34), and differential item functioning (DIF) according to diagnosis or sociodemographic characteristics (35). Since the latter DIFs were found to be minor, items with DIF were not excluded if content or measurement considerations advocated their preservation.…”

“…The Thyroid-Related Patient-Reported Outcome (ThyPRO) instrument was developed as a comprehensive thyroidrelated standalone PRO for patients with any benign thyroid disease (15)(16)(17). It was crucial to the developers that it covered all benign thyroid diseases in order for it to maintain content validity when patients ''converted'' from one diagnosis to the other because of treatment (e.g., patients with nontoxic goiter becoming hypothyroid and requiring thyroid hormonal substitution after thyroidectomy).…”

Thyroid hormone and its metabolites in relation to quality of life in patients treated for differentiated thyroid cancer

“…First, the presence of associated autoimmune diseases or thyroid autoimmunity per se could account for persisting symptoms. [7][8][9] However, cured patients with differentiated thyroid carcinoma (DTC) on LT4 replacement therapy have also been shown to have an impaired quality of life (QoL). 10,11 Second, it might be the inadequacy of LT4 treatment to restore physiological T4 and T3 concentrations in serum and tissues.…”

Quality of life in patients treated with radiofrequency ablation for thyroid nodules

“…SF-36, Hamilton scale and the Kellner Symptoms Questionnaire). Questionnaires for QoL evaluation have been used in numerous benign and malignant thyroid diseases, such as benign goitre treated with RAI following rhTSH premedication, autoimmune hypothyroidism and chronic autoimmune thyroiditis [14][15][16][17][18][19][20][21][22][23] The "general score" of ThyPRO, which answers the question "In the last 4 weeks, has thyroid disease had a negative effect on your quality of life? ", improved from the 3rd month onwards.…”