Objective: This study was performed to evaluate the impact of cured differentiated thyroid carcinoma (DTC) on quality of life. Previous studies on quality of life in patients with DTC were hampered by small patient numbers or limited quality-of-life parameters or were uncontrolled.
Design: This was a cross-sectional case-control study.
Method: We assessed quality of life in 153 cured DTC patients with a median duration of cure of 6.34 yr (range 0.3-41.8) and studied the contribution of disease-specific, biochemical, and social variables, focusing on the degree of TSH suppression. Four validated health-related questionnaires were used (Short Form-36, Multidimensional Fatigue Index-20, Hospital Anxiety and Depression Scale, and Somatoform Disorder Questionnaire), including multiple aspects of physical, psychological, and social functioning. Patients were compared with 113 controls selected by patients themselves (control group I) and 336 pooled age- and gender-matched controls from other Leiden quality-of-life studies (control group II).
Results: Patients had significantly decreased quality of life in 11 of 16 subscales when compared with control group I. In comparison with control group II, decreased scores in 13 of 16 items were observed. An important independent predictor for quality of life was duration of cure. Quality-of-life parameters were not influenced by serum TSH levels both measured at the time of quality-of-life assessment and measured over time since initial therapy.
Conclusions: Patients cured for DTC have impaired quality of life, independently of TSH level. Quality-of-life parameters were inversely affected by duration of cure and consequently may be restored after prolonged follow-up.