Directly observed therapy for multidrug-resistant TB decreases mortality rate

DOT is a strategy to ensure that people with TB adhere to a long and challenging drug regimen by having someone observe and record the taking of all medicines. MDR TB is resistant to at least isoniazid and rifampin, two of the main therapeutic agents used to treat TB.

"Directly observed therapy is already recommended to treat all forms of TB, but it's valuable to have this data on the effectiveness among patients with MDR TB," said Jorge Salinas, MD, lead study author and epidemic intelligence service officer in the Centers for Disease Control and Prevention's Division of Tuberculosis Elimination. "We wanted to assess whether the strategy influenced mortality in MDR TB patients."

The researchers analyzed data from 1993-2013 for 3,434 MDR TB patients, 709 of whom died during the follow-up period. The proportion of patients on DOT increased from 74 percent during 1993-2002 to 95 percent during 2002-2013.

Among MDR TB patients in the study:

• 34 percent were infected with HIV.
• 18 percent had a previous diagnosis of TB disease.
• 17 percent had an additional drug resistance.
• 88 percent were born in either an Asian or Hispanic country.

The study adjusted mortality findings for these and other characteristics and found that across all demographic and clinical groups those who underwent DOT had significantly lower mortality.

"This protective effect may come from DOT alone or from other patient-centered measures, such as transportation assistance or food stamps given along with DOT by TB treatment facilities to improve treatment adherence," Dr. Salinas said. "The findings reinforce that all patients with MDR TB should receive DOT and other patient-centered measures to ensure patients complete their treatment."