Tuberculin skin test and interferon-gamma release assay use among privately insured persons in the United States.

OBJECTIVE: To describe tuberculin skin test (TST) and interferon-gamma release assay (IGRA) (i.e., QuantiFERON®-TB [QFT] and T-SPOT®.TB [T-SPOT]) use among privately insured persons in the United States over a 15-year period. METHODS: We used current procedural terminology (CPT) codes for the TST and IGRAs to extract out-patient claims (2000-2014) and determined usage (claims/100 000). The χ2 test for trend in proportions was used to describe usage trends for select periods. RESULTS: The TST was the dominant (>80%) test in each year. Publication of guidelines preceded the assignment of QFT and T-SPOT CPT codes by 1 year (2006 for QFT; 2011 for T-SPOT). QFT usage was higher (P < 0.01) than T-SPOT in each year. The average annual increase in the use of QFT was higher than that of T-SPOT (35 vs. 3.8/100 000), and more so when the analytic period was 2011-2014 (65 vs. 38/100 000). However, during that 4-year period (2011-2014), TST use trended downward, with an average annual decrease of 28/100 000. The annual proportion of enrollees tested ranged from 1.1% to 1.5%. CONCLUSIONS: These results suggest a gradual shift from the use of the TST to the newer IGRAs. Future studies can assess the extent, if any, to which the shift from the use of the TST to IGRAs evolved over time.

Tuberculosis hospitalization expenditures per patient from private health insurance claims data, 2010-2014.

OBJECTIVE: To determine hospitalization expenditures for tuberculosis (TB) disease among privately insured patients in the United States. METHODS: We extracted TB hospital admissions data from the 2010-2014 MarketScan® commercial database using International Classification of Diseases version 9 codes for TB (011.0-018.96) as the principal diagnosis. We estimated adjusted average expenditures (in 2014 USD) using regression analyses controlling for patient and claim characteristics. We also estimated the total expenditure paid by enrollee and insurance, and extrapolated it to the entire US employer-based privately insured population. RESULTS: We found 892 TB hospitalizations representing 825 unique enrollees over the 5-year period. The average hospitalization expenditure per person (including multiple hospitalizations) was US$33 085 (95%CI US$31 606- US$34 565). Expenditures for central nervous system TB (US$73 065, 95%CI US$59 572-US$86 558), bone and joint TB (US$56 842, 95%CI US$39 301-US$74 383), and miliary/disseminated TB (US$55 487, 95%CI US$46 101-US$64 873) were significantly higher than those for pulmonary TB (US$28 058, 95%CI US$26 632-US$29 484). The overall total expenditure for hospitalizations for TB disease over the period (2010-2014) was US$38.4 million; it was US$154 million when extrapolated to the entire employer-based privately insured population in the United States. CONCLUSIONS: Hospitalization expenditures for some forms of extra-pulmonary TB were substantially higher than for pulmonary TB.