External Validation of the GREAT Score in Turkish Patients with Gravesʼ Hyperthyroidism Treated with the Titration Regimen Method of Antithyroid Drugs: A Multicenter Study

Abstract

Recently, the Gravesʼ Recurrent Events After Therapy score (GREAT) was proposed as a useful tool to predict relapse before starting antithyroid drugs (ATD) in patients with Gravesʼ disease (GD). Therefore, we intended to assess the validity of the GREAT score in Turkish patients with GD, including patients who experienced a poorly controlled disease (multiple episodes of hyperthyroidism followed by euthyroidism or rarely hypothyroidism) during ATD dose titration. This is a retrospective multicenter study including 517 patients with the first episode of GD who were treated for at least 12 months. The patients were classified as relapse+poorly controlled disease (non-remission) and remission groups. During a median follow-up time of 35 months (12–144 months), 191 (37%) patients experienced a relapse, 136 (26.3%) a poorly controlled disease, and 190 (36.7%) remained in remission. Patients with non-remission disease tended to have significantly higher serum levels of TRAb, fT4, and fT3, and have larger goiter sizes on palpation at baseline, as compared with the remission group. Non-remission disease occurred in 12, 35, and, 53% of the patients falling into GREAT class I, II, and III, respectively (hazard ratio 2.56, 95% CI 2.02–3.51, p=0.012, and hazard ratio 3.54, 95% CI 2.12–5.91, p<0.001, for GREAT class II and III against class I, respectively). According to our study, the GREAT score is a useful tool to predict the risk of relapse as well as the occurrence of poorly controlled disease before starting treatment with ATDs.

The association of TSH-receptor antibody with the clinical and laboratory parameters in patients with newly diagnosed Graves’ hyperthyroidism: experience from a tertiary referral center including a large number of patients with TSH-receptor antibody-negative patients with Graves’ hyperthyroidism

“…However, although TRAb levels were significantly higher in younger male patients, in regression analysis, age at diagnosis was not found to be an independent contributor to TRAb levels. We believe that higher TRAb levels observed in male patients at the initial diagnosis of GD in our study could support the results of prior studies reporting a higher frequency of relapse after discontinuation of the antithyroid drugs as well as a more severe disease course in male patients with GD [11,12,20].…”

“…The age of the patient during the first diagnosis is another factor associated with the outcome of GD. Patients < 40 years old at diagnosis have also a higher risk of relapse after treatment with ATDs [12,13]. However, the association between gender as well as age with TRAb at the initial diagnosis of GD is not well known.…”

The relationship between atherosclerotic disease and relapse during ATD treatment

“…Interestingly, it is demonstrated that patients with goiter gradation Grade II and above have a higher recurrence rate and relapse in a relatively short period of time than patients with goiter gradation Grade I. This finding is in agreement with that of Turkish study enrolled 517 patients with GD after ATD withdrawal ( 30 ). Meanwhile, there has also been an association between goiter and relapse after ATD withdrawal in previous studies ( 28 , 31 ).…”

A New Perspective in the Management of Graves’ Hyperthyroidism

“…The relapse rates in class I, II, and III of this so-called Graves' recurrent events after therapy (GREAT) score were 16%, 44%, and 68%, respectively. The GREAT scoring system has been validated in three studies (35)(36)(37). Table 2 shows the results of GREAT risk scores in four studies.…”