Kristien Boelaert1, Patrick Maisonneuve, Barbara Torlinska, Jayne A Franklyn. 1. Centre for Endocrinology, Diabetes, and Metabolism, School of Clinical and Experimental Medicine, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, United Kingdom. k.boelaert@bham.ac.uk
Abstract
CONTEXT: Hyperthyroidism is common, but opinions regarding optimal therapy with antithyroid drugs or radioiodine (131-I) differ. There are no randomized trials comparing these options in terms of mortality. OBJECTIVE: The aim of the study was to determine whether mortality associated with hyperthyroidism varies with treatment administered or other factors. DESIGN, SETTING, AND PATIENTS: We conducted a prospective observational population-based study of 1036 subjects aged ≥ 40 years presenting to a single specialist clinic from 1989-2003 with a first episode of hyperthyroidism who were followed until June 2012. INTERVENTIONS: Antithyroid drugs or radioiodine (131-I) were administered. MAIN OUTCOME MEASURES: We compared causes of death with age-, sex-, and period-specific mortality in England and Wales and used within-cohort analysis of influence of treatment modality, outcome, disease etiology, severity and control, and comorbidities. RESULTS: In 12 868 person-years of follow-up, 334 died vs 290.6 expected (standardized mortality ratio [SMR], 1.15 [95% confidence interval (CI),1.03-1.28]; P = .01). Increased all-cause mortality largely reflected increased circulatory deaths (SMR, 1.20 [95% CI, 1.01-1.43]; P = .04). All-cause mortality was increased for the person-years accumulated during thionamide treatment (SMR, 1.30 [95% CI, 1.05-1.61]; P = .02) and after 131-I not associated with hypothyroidism (SMR, 1.24 [95% CI, 1.04-1.46]; P = .01) but not during T₄ replacement for 131-I-induced hypothyroidism (SMR, 0.98 [95% CI, 0.82-1.18]; P = .85). Within-cohort analysis comparing mortality during thionamide treatment showed a similar hazard ratio (HR) for all-cause mortality when 131-I did not result in hypothyroidism (HR, 0.95 [95% CI, 0.70-1.29]), but reduced mortality with 131-I-induced hypothyroidism (HR, 0.70 [95% CI, 0.51-0.96]). Reduced mortality associated with hypothyroidism was seen only in those without significant comorbidities and not in those with other serious diseases. Atrial fibrillation at presentation (P = .02) and an increment of 10 pmol/L in serial free T₄ concentration during follow-up (P = .009) were independently associated with mortality. CONCLUSIONS: Among hyperthyroid subjects aged 40 years or older, mortality was increased during periods of thionamide treatment and after radioiodine not resulting in hypothyroidism, but not during follow-up after radioiodine-induced hypothyroidism. Independent associations of mortality with atrial fibrillation and incomplete biochemical control during treatment indicate potential causative links with poor outcome.
CONTEXT: Hyperthyroidism is common, but opinions regarding optimal therapy with antithyroid drugs or radioiodine (131-I) differ. There are no randomized trials comparing these options in terms of mortality. OBJECTIVE: The aim of the study was to determine whether mortality associated with hyperthyroidism varies with treatment administered or other factors. DESIGN, SETTING, AND PATIENTS: We conducted a prospective observational population-based study of 1036 subjects aged ≥ 40 years presenting to a single specialist clinic from 1989-2003 with a first episode of hyperthyroidism who were followed until June 2012. INTERVENTIONS: Antithyroid drugs or radioiodine (131-I) were administered. MAIN OUTCOME MEASURES: We compared causes of death with age-, sex-, and period-specific mortality in England and Wales and used within-cohort analysis of influence of treatment modality, outcome, disease etiology, severity and control, and comorbidities. RESULTS: In 12 868 person-years of follow-up, 334 died vs 290.6 expected (standardized mortality ratio [SMR], 1.15 [95% confidence interval (CI),1.03-1.28]; P = .01). Increased all-cause mortality largely reflected increased circulatory deaths (SMR, 1.20 [95% CI, 1.01-1.43]; P = .04). All-cause mortality was increased for the person-years accumulated during thionamide treatment (SMR, 1.30 [95% CI, 1.05-1.61]; P = .02) and after 131-I not associated with hypothyroidism (SMR, 1.24 [95% CI, 1.04-1.46]; P = .01) but not during T₄ replacement for 131-I-induced hypothyroidism (SMR, 0.98 [95% CI, 0.82-1.18]; P = .85). Within-cohort analysis comparing mortality during thionamide treatment showed a similar hazard ratio (HR) for all-cause mortality when 131-I did not result in hypothyroidism (HR, 0.95 [95% CI, 0.70-1.29]), but reduced mortality with 131-I-induced hypothyroidism (HR, 0.70 [95% CI, 0.51-0.96]). Reduced mortality associated with hypothyroidism was seen only in those without significant comorbidities and not in those with other serious diseases. Atrial fibrillation at presentation (P = .02) and an increment of 10 pmol/L in serial free T₄ concentration during follow-up (P = .009) were independently associated with mortality. CONCLUSIONS: Among hyperthyroid subjects aged 40 years or older, mortality was increased during periods of thionamide treatment and after radioiodine not resulting in hypothyroidism, but not during follow-up after radioiodine-induced hypothyroidism. Independent associations of mortality with atrial fibrillation and incomplete biochemical control during treatment indicate potential causative links with poor outcome.
Authors: Jan Taprogge; Paul M D Gape; Lily Carnegie-Peake; Iain Murray; Jonathan I Gear; Francesca Leek; Steve L Hyer; Glenn D Flux Journal: Thyroid Date: 2021-12 Impact factor: 6.568
Authors: Eyun Song; Mina Kim; Sojeong Park; Min Jeong Park; Jung A Kim; Eun Roh; Ji Hee Yu; Nam Hoon Kim; Ji A Seo; Sin Gon Kim; Nan Hee Kim; Kyung Mook Choi; Sei Hyun Baik; Hye Jin Yoo Journal: Front Endocrinol (Lausanne) Date: 2021-10-08 Impact factor: 5.555