Health-Related Quality of Life (HRQoL) of Adult Filipinos with Graves' Disease cured by Radioiodine Therapy compared to those controlled by Antithyroid Drugs at University of Santo Tomas Hospital: A Pilot Study

Abstract

Objective: The study aims to develop and validate the Filipino version of Thyroid-disease specific quality of life Patient Reported Outcome (ThyPROph) questionnaire, and to conduct a pilot study comparing the quality of life of patients with Graves' disease at University of Santo Tomas Hospital (USTH) after receiving radioactive iodine ablation (RAI) or anti-thyroid drug (ATD) using the validated ThyPROph.

Methodology: This study has 2 phases. Phase 1 is the development and validation of the ThyPROph with prior translation and pretesting to Graves' disease patients. Phase 2 is the pilot study involving 58 euthyroid patients with Graves' disease recruited to answer the validated ThyPROph. All of the participants completed the ThyPROph. A cross sectional comparative design was used to compare health-related quality of life (HRQoL) under two modes of treatment for Graves' disease: RAI and ATD. Likewise, correlation of the domains with the demographics was determined using Pearson correlation coefficient and Spearman rank signed test.

Results: For the phase 1 study, internal consistency exists across all domains of ThyPROph with Cronbach's alpha of 0.839. Overall, discriminant validity falls within range of 0.028-0.606 and convergent validity showed moderate correlations. Phase 2 study showed that there is a significant difference in the domains "goiter symptoms" (p=0.0209), "emotional susceptibility" (p=0.0067) and "impaired daily life" (p=0.0463). The HRQoL is significantly better in the RAI group based on these three domains. Statistically significant correlations exist between goiter grade and goiter symptoms domain (p=0.0001), gender and impaired daily life domain (p=0.016), cosmetic complaints domain with age (p=0.002), marital status (p=0.046), and disease duration (p=0.005).

Limitations: Results are not powered to achieve the primary objective because complications of Graves' disease were excluded. The reliability of the domains is reduced. A prospective randomized study is more ideal.

Conclusion: Quality of life of patients with Graves' disease as assessed by ThyPROph is significantly better with RAI compared to ATD. RAI therapy can be considered as the better treatment option in our setting especially for patients who have noticeable goiters with symptoms attributable to their goiters, and those with emotional instability.

Keywords: Graves’ disease; antithyroid drug; quality of life; radioactive iodine.