Inequitable Long-Term Outcomes for an Indigenous Population After Definitive Treatment of Patients With Graves Disease

Abstract

Background Māori, the indigenous people of Aotearoa/New Zealand, have an increased incidence of Graves disease and often require more than one radioiodine (RAI) dose, raising the question as to whether surgery may be preferable in this population. However, there is a lack of outcome data after definitive therapy in an indigenous population. Aim To assess ethnic differences in thyroid status after definitive therapy for Graves disease. Methods Single-center retrospective review of patients treated by RAI or thyroidectomy from 1 December 2001 to 31 March 2013. TSH levels at 1, 2, 5, and 10 years after treatment were recorded. Results A total of 798 patients were included: 589 received RAI, and 209 underwent surgery. Overall, 48% of patients were euthyroid at 1 year after definitive treatment, and 63.5% were euthyroid by 10 years. Māori were less likely to be euthyroid when compared with Europeans at all time points (e.g., 29.7% vs 57.3% at 1 year and 52.2% vs 70.9% at 10 years, P < 0.0005). Māori were more likely to receive more than one dose of RAI compared with Europeans (30.2% vs 14.2%, P < 0.0005). Persistent thyrotoxicosis at 1 year after RAI was seen in 25.8% of Māori compared with 8.3% of Europeans (P < 0.0005). Conclusions Māori have lower rates of optimal thyroid levels than their European counterparts at all time points studied. Early disparity was associated with a higher RAI failure rate. Late differences were due to higher rates of untreated hypothyroidism. Overall, euthyroid rates were low, indicating the need for improvement in care, particularly for indigenous peoples.

Ethnic disparities for thyroid surgery

“…17 In clinical practice, system factors, clinician factors and patient factors have been described as drivers of health disparity. 6 Our study is limited by low patient numbers; however, the magnitude of difference between M aori and non-M aori findings cannot be ignored. Continuing current management will simply extend the disparity with larger thyroids associated with more complications and worse health outcomes.…”

“…Jones suggested differential access to determinants of health, differential access to health care and differences in health care received being factors driving health inequalities 17 . In clinical practice, system factors, clinician factors and patient factors have been described as drivers of health disparity 6 …”

“…Current demographics of New Zealand show 16.5% of the population being Māori 5 . Māori patients were less likely to be euthyroid compared to non‐Māori despite receiving the same definitive treatment 6 …”

“…5 M aori patients were less likely to be euthyroid compared to non-M aori despite receiving the same definitive treatment. 6 Key indications for thyroid surgery include malignancies, compressive multinodular goitre (MNG) and thyrotoxicosis. The complexity of surgery varies depending on the diagnosis and extent of disease.…”

Resultados de la tiroidectomía total en el tratamiento del hipertiroidismo

“…La buena respuesta al tratamiento quirúrgico publicada por Marques 18 se dio en 77% de casos. En el estudio de Tamatea 19 , se logró normofunción tiroidea solo en el 48% de los casos tras seguimiento de 1 año, y del 63,5% a los 10 años de seguimiento. En nuestro estudio se logró la normofunción en 19 casos (73,07%), con un periodo de seguimiento de 36 meses.…”