[An index based on the age and free thyroxine rate predicts the likelihood of Graves' disease in hyperthyroidism].

Abstract

PURPOSE Graves' disease patients are generally younger and have more severe symptoms than other thyrotoxic patients. We established an index based on the normalized free thyroxine rate and age, capable of predicting Graves' disease in thyrotoxic patients. METHODS The predictive index was established from a discriminant analysis from a retrospective population of 114 thyrotoxic patients and its predictivity was confirmed by cross-validation on the same population. RESULTS The index IGD = 41.38 - age + 37.05 x in (normalized free T4) classifies accurately 80.7% of the patients (CI 95%: 72.2-87.5). Sensitivity is 78.5% (CI 95%: 66.5-87.7). Specificity is 83.7% (CI 95%: 70.3-92.7). Predictive positive value is 86.4% (CI 95%: 75.0-94.0). Negative predictive value is 74.5% (CI 95%: 61.0-85.3). Likelihood ratio of Graves' disease in case of prediction by the index is 4.81 (CI 95%: 2.66-9.32). Likelihood ratio of Graves' disease in case of non-prediction by the index is 0.26 (IC 95%: 0.16-0.40). CONCLUSION A simple index based on the normalized free thyroxine rate and age provides an early diagnosis orientation toward Graves' disease in thyrotoxic patients who are waiting for complementary investigations.

Cite this paper

@article{Kettaneh2001AnIB, title={[An index based on the age and free thyroxine rate predicts the likelihood of Graves' disease in hyperthyroidism].}, author={Adrien Kettaneh and Philippe Guilpain and Olivier Fain and Jacques Pari{\`e}s and Michel Thomas and Marc Sitbon}, journal={La Revue de medecine interne}, year={2001}, volume={22 6}, pages={530-5} }