Factors associated with failure to complete isoniazid therapy for latent tuberculosis infection in children and adolescents

Background: Completion of the recommended 9-month course of isoniazid to treat latent tuberculosis infection in children remains poor and is often affected by adverse effects, including hepatitis, to medication. We evaluated the frequency of isoniazid therapy completion and factors associated with failure to complete therapy in patients aged 0-18 years.

Methods: We performed a retrospective review of medical records for patients aged 0-18 years who were referred for isoniazid therapy between January 2005 and August 2011 at 2 California county sites: a public health department and a pediatric latent tuberculosis infection clinic. Medication adherence to isoniazid therapy was measured by monthly pill count.

Results: There were 1872 eligible patients who were referred for isoniazid therapy. Of the 1587 patients who met inclusion criteria and initiated treatment, 1235 patients (78%) completed the 9-month therapy, including 1046 of 1308 patients aged <15 years (80%) and 189 of 268 patients aged 15-18 years (71%). Factors that were significantly associated with failure to complete therapy included age 15-18 years, non-Hispanic race, development of hepatitis, and symptoms of adverse effects. The association between age and the development of hepatitis was similar for male and female patients.

Conclusion: Failure to complete isoniazid therapy in patients aged 0-18 years is affected by older age, non-Hispanic race, development of hepatitis, and symptoms of adverse effects. Additional support is needed for adolescents to complete therapy for latent tuberculosis infection.