Mn. Gourevitch et al., Effectiveness of isoniazid chemoprophylaxis for HIV-infected drug users athigh risk for active tuberculosis, AIDS, 13(15), 1999, pp. 2069-2074
Objective: To define the effectiveness of chemoprophylaxis, outside of a cl
inical trial setting, in preventing tuberculosis among tuberculin-reactive
and anergic HIV-infected drug users at high risk of developing active tuber
culosis.
Design: An observational cohort study.
Setting: Methadone maintenance treatment program with on-site primary care.
Participants: Current or former drug users enrolled in methadone treatment.
Interventions: Annual skin testing for tuberculosis infection and anergy wa
s performed, and eligible patients were offered daily isoniazid for 12 mont
hs and followed prospectively.
Main outcome measure: The development of active tuberculosis.
Results: A total of 155 persons commenced chemoprophylaxis. Among tuberculi
n reactors, tuberculosis rates were 0.51 and 2.07/100 person-years in those
completing 12 months versus those not taking prophylaxis [rate ratio 0.25,
95% confidence interval (CI) 0.06-1.01]. Among anergic individuals, compar
able rates were 0 and 1.44/100 person-years. Lower tuberculosis rates among
completers were not attributable to differences in immune status between t
he treated and untreated groups.
Conclusion: The completion of isoniazid chemoprophylaxis was associated wit
h a marked reduction in tuberculosis risk among tuberculin reactors and ane
rgic persons in this high-risk population. These data support aggressive ef
forts to provide a complete course of preventative therapy to HIV-infected
tuberculin reactors, and lend weight to the findings of others that isoniaz
id can reduce the rate of tuberculosis in high-risk anergic HIV-infected pe
rsons. (C) 1999 Lippincott Williams & Wilkins.