Risk factors that can up the odds of a patient with Grave’s hyperthyroidism developing orbitopathy have been highlighted in an Australian study.

Published online first in the Journal of Clinical Endocrinology and Metabolism the research involved 10423 patients with Grave’s hyperthyroidism (GH) taking part in the multicentre Australian Thyroid-associated Orbitopathy Research (ATOR) group study.

Results showed that the odds of GO increased by 17% for each decade increase in the age of onset of disease (OR 1.17, CI: 1.06-1.29, p=0.002) and by 7% for each year increase in the duration of disease (OR 1.07, CI: 1.05–1.10, p<0.001).

Smoking increased the odds for GO by 2.22 for current smokers and 2.07 for ex-smokers (p<0.001), compared with those who had never smoked.

The odds of GO were 86% less in Graves’ patients using anti-thyroid medication than those not (OR 0.14, CI 0.06 – 0.34, p<0.001).

Increasing severity of oculomotility restriction predicted the development of dysthyroid optic neuropathy (DON).

“This clinical finding remains useful in predicting DON even in GO patients who have been treated previously,” wrote the study authors that included endocrinologist Peter Ebeling from Monash University in Victoria.

A novel finding that strabismus predicted the likelihood of DON would also prove useful in clinical assessment, they said.

“Arguably older patients with severe restrictive oculomotility and active orbital inflammation would benefit from early medical treatment for GO to prevent the development of DON,” they added.