Abstract
BACKGRUOUND: Patients with thyroid cancer undergo less extensive surgery and additional therapies compared to those with other cancers. We aimed to compare the quality of life (QoL) between patients with thyroid cancer and healthy subjects using representative data from Korea. Differences in QoL of thyroid cancer survivors according to the duration after cancer diagnosis was also evaluated. METHODS: This population-based cohort study included 50,278 subjects who participated in the Korea National Health and Nutrition Examination Survey between 2007 and 2017. QoL was compared between patients with thyroid cancer and healthy subjects using self-reported data from the EuroQoL (EQ)-5 dimension (5D) and EQ-visual analog scale (VAS). Propensity score matching was used to match thyroid cancer survivors to healthy subjects (1:5 matching). RESULTS: Linear regression with univariate analysis showed that the presence of thyroid cancer was positively correlated with better EQ-5D index scores (β-coefficient=0.010, p=0.046). After adjusting for multiple covariables, statistical significance was maintained. EQ-VAS fails to demonstrate any significant correlation. Among the EQ-5D categories, patients with thyroid cancer showed better self-care than healthy subjects. Thyroid cancer duration did not correlate with the EQ-5D index score. In subgroup analyses, compared to patients with thyroid cancer duration of <5 years, no significant difference was observed in the correlation between the EQ-5D index score and survival duration in those with thyroid cancer duration of 5 to 9 years and ≥10 years. CONCLUSION: Using a large-scale nationwide population-based database, our study demonstrated better QoL, especially in terms of self-care, among thyroid cancer survivors than among healthy subjects without cancer.