Treatment Practices, Outcomes, and Costs of Multidrug-Resistant and Extensively Drug-Resistant Tuberculosis, United States, 2005–2007

Suzanne M. Marks

, Jennifer Flood, Barbara Seaworth, Yael Hirsch-Moverman, Lori Armstrong, Sundari Mase, Katya Salcedo, Peter Oh, Edward A. Graviss, Paul W. Colson, Lisa Armitige, Manuel Revuelta, Kathryn Sheeran, and the TB Epidemiologic Studies Consortium

Author affiliations: Centers for Disease Control and Prevention, Atlanta, Georgia, USA (S.M. Marks, L. Armstrong, S. Mase, TB Epidemiologic Studies Consortium); California Department of Public Health, Richmond, California, USA (J. Flood, K. Salcedo, P. Oh); Texas Department of State Health Services, Tyler, Texas, USA (B. Seaworth, L. Armitige, K. Sheeran); University of Texas Health Science Center, Tyler (B. Seaworth, L. Armitige, K. Sheeran); ICAP/Columbia University, New York, New York, USA (Y. Hirsch-Moverman, P.W. Colson, M. Revuelta); Methodist Hospital Research Institute, Houston, Texas, USA (E.A. Graviss)

Abstract

To describe factors associated with multidrug-resistant (MDR), including extensively-drug-resistant (XDR), tuberculosis (TB) in the United States, we abstracted inpatient, laboratory, and public health clinic records of a sample of MDR TB patients reported to the Centers for Disease Control and Prevention from California, New York City, and Texas during 2005–2007. At initial diagnosis, MDR TB was detected in 94% of 130 MDR TB patients and XDR TB in 80% of 5 XDR TB patients. Mutually exclusive resistance was 4% XDR, 17% pre-XDR, 24% total first-line resistance, 43% isoniazid/rifampin/rifabutin-plus-other resistance, and 13% isoniazid/rifampin/rifabutin-only resistance. Nearly three-quarters of patients were hospitalized, 78% completed treatment, and 9% died during treatment. Direct costs, mostly covered by the public sector, averaged $134,000 per MDR TB and $430,000 per XDR TB patient; in comparison, estimated cost per non-MDR TB patient is $17,000. Drug resistance was extensive, care was complex, treatment completion rates were high, and treatment was expensive.

Drug-resistant Mycobacterium tuberculosis poses substantial obstacles to tuberculosis (TB) control. In the United States, multidrug-resistant (MDR) TB (resistant to at least isoniazid and rifampin) comprises only 1.0%–1.5% of TB cases but requires lengthy regimens of toxic drugs, imposes high costs on the health care system and society, and causes high mortality rates.

Studies of MDR TB in the United States have been limited by small sample sizes, limited study periods, minimal information on outcomes and costs, or reliance solely on surveillance data (1–6), which omit some cases of acquired drug resistance and changes in regimens. Costs of treating MDR TB are not routinely collected or reported.

Our study describes and analyzes characteristics associated with drug resistance, timely diagnosis, treatment practices, outcomes, and costs associated with MDR TB for cases reported to the Centers for Disease Control and Prevention (CDC) by California, New York, NY, and Texas during 2005–2007. These 3 areas contribute about half of US MDR TB cases annually.

Methods

CDC and local institutional review boards approved the study and granted a waiver of patient informed consent and patient authorization. We defined a 5-drug regimen (Technical Appendix

[PDF - 300 KB - 24 pages]) to be consistent with US and World Health Organization recommendations (7,8). All study definitions are in the Technical Appendix

[PDF - 300 KB - 24 pages].