TSI assay utilization: impact on costs of Graves' hyperthyroidism diagnosis

Abstract

Objectives: Thyroid-stimulating immunoglobulins (TSIs) are autoantibodies that bind to the thyroid-stimulating hormone (TSH) receptor on thyroid cells, resulting in Graves' disease (GD), the most common cause of hyperthyroidism. Recently published guidelines recognize the value of anti-TSH receptor antibodies, and a TSI test with high sensitivity and specificity for GD, recently cleared by the US Food and Drug Administration, is now available. Despite this, existing diagnostic algorithms for hyperthyroidism do not currently include TSI testing except in specific cases like pregnancy. The objectives of this analysis are to understand whether incorporating a test that specifically detects TSIs into existing algorithms results in cost savings and reduces time to diagnosis for payers and managed care organizations.

Study design: An evidence-based economic model was developed to determine the average time to diagnosis and annual costs associated with various diagnostic algorithms for GD in a population of 100,000 managed care enrollees. Diagnostic algorithms used in current practice and hypothetical algorithms that include the TSI test were identified using published clinical guidelines and interviews with practicing endocrinologists. The model estimates costs of current and TSI test-based diagnostic algorithms using payment amounts for laboratory tests, procedures, and physician visits.

Results: Compared with non-TSI algorithms, 100% use of algorithms that include the TSI test result in 46% faster time to diagnosis and generate 47% overall cost savings due in large part to reductions in costly procedures and specialist office visits.

Conclusions: Incorporation and early utilization of the TSI in vitro diagnostic test into current diagnostic algorithms confers cost savings and shortens time to diagnosis.