title: Treatment completion for latent tuberculosis infection: a retrospective cohort study comparing 9 months of isoniazid, 4 months of rifampin and 3 months of isoniazid and rifapentine.
abstract: The U.S. Centers for Disease Control and Prevention (CDC) recommended a new regimen for treatment of latent tuberculosis (three months of weekly isoniazid and rifapentine) in late 2011. While completion rates of this regimen were reported to be higher than nine months of isoniazid, little is known about the completion rates of three months of isoniazid and rifapentine compared to nine months of isoniazid or four months of rifampin in actual use scenarios.
  
  
  
  We conducted a retrospective cohort study comparing treatment completion for latent tuberculosis (TB) infection in patients treated with nine months of isoniazid, three months of isoniazid and rifapentine or four months of rifampin in outpatient clinics and a public health TB clinic in Seattle, Washington. The primary outcome of treatment completion was defined as 270 doses of isoniazid within 12 months, 120 doses of rifampin within six months and 12 doses of isoniazid and rifapentine within four months.
  
  
  
  Three hundred ninety-three patients were included in the study. Patients were equally likely to complete three months of weekly isoniazid and rifapentine or four months of rifampin (85% completion rate of both regimens), as compared to 52% in the nine months of isoniazid group (p < 0.001). These associations remained statistically significant even after adjusting for clinic location and type of monitoring. Monitoring type (weekly versus monthly versus less often than monthly) had less impact on treatment completion than the type of treatment offered.
  
  
  
  Patients were equally as likely to complete the three months of isoniazid and rifapentine as four months of rifampin. Four months of rifampin is similar in efficacy compared to placebo as isoniazid and rifapentine but does not require directly observed therapy (DOT), and is less expensive compared to combination therapy with isoniazid and rifapentine, and thus can be the optimal treatment regimen to achieve the maximal efficacy in a community setting.
authors.affiliation: Division of General Internal Medicine, Department of Medicine, University of Washington School of Medicine, Box 354765, 4245 Roosevelt Way NE, Seattle, WA, 98105, USA. ahearst@uw.edu.
authors.forename: Adelaide H
authors.initials: AH
authors.lastname: McClintock
authors.affiliation: Division of Allergy & Infectious Diseases, Department of Medicine, University of Washington School of Medicine, Seattle, USA.
authors.forename: McKenna
authors.initials: M
authors.lastname: Eastment
authors.affiliation: Division of General Internal Medicine, Department of Medicine, University of Washington School of Medicine, Box 354765, 4245 Roosevelt Way NE, Seattle, WA, 98105, USA.
authors.forename: Christy M
authors.initials: CM
authors.lastname: McKinney
authors.affiliation: Pharmacy Department, Harborview Medical Center, Seattle, USA.
authors.forename: Caroline L
authors.initials: CL
authors.lastname: Pitney
authors.affiliation: Division of Pulmonary & Critical Care Medicine, Department of Medicine, University of Washington School of Medicine, Seattle, USA.|Tuberculosis Control Program, Public Health - Seattle & King County, Seattle, USA.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Narita
authors.affiliation: Division of Pulmonary & Critical Care Medicine, Department of Medicine, University of Washington School of Medicine, Seattle, USA.
authors.forename: David R
authors.initials: DR
authors.lastname: Park
authors.affiliation: Division of Allergy & Infectious Diseases, Department of Medicine, University of Washington School of Medicine, Seattle, USA.
authors.forename: Shireesha
authors.initials: S
authors.lastname: Dhanireddy
authors.affiliation: Division of General Internal Medicine, Department of Medicine, University of Washington School of Medicine, Box 354765, 4245 Roosevelt Way NE, Seattle, WA, 98105, USA.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Molnar
mesh_terms: D000328:Adult; D000995:Antitubercular Agents / Q000627:therapeutic use*; D002487:Centers for Disease Control and Prevention, U.S.; D023801:Directly Observed Therapy; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D007538:Isoniazid / Q000627:therapeutic use*; D055985:Latent Tuberculosis / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D010349:Patient Compliance / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D012293:Rifampin / Q000031:analogs & derivatives* / Q000627:therapeutic use*; D014481:United States / Q000453:epidemiology; D014861:Washington / Q000453:epidemiology
chemical_list: D000995:Antitubercular Agents; D007538:Isoniazid; D012293:Rifampin; C018421:rifapentine
keywords: Isoniazid; Latent Tuberculosis Infection; Rifampin; Rifapentine; Treatment adherence