Adherence to isoniazid preventive therapy in children exposed to tuberculosis: a prospective study from Guinea-Bissau

OBJECTIVE: To assess adherence to isoniazid preventive therapy (IPT) in children exposed to adult pulmonary tuberculosis (TB) at home. METHODS: Children were enrolled on IPT if they were aged <= 5 years or 5-15 years and presented a tuberculin skin test induration of >= 1.0 mm. Children were included from the demographic surveillance system of the Bandim Health Project in Bissau, Guinea-Bissau. The main outcome measures were adherence, completion rates and side effects during 9 months of IPT. The main outcome was 6 consecutive months of at least 80% adherence. RESULTS: A total of 2631 children were identified as contacts of adult TB cases. Among the children identified, 1895 (72%) were evaluated for eligibility for IPT, and 820 were enrolled in the study: 609 were aged 5 years and 211 aged 5-15 years. A total of 79% of the prescribed doses were taken, with 65% of the children taking >80% of their doses. In all, 51% completed more than 6 consecutive months of IPT. CONCLUSION: Overall adherence to IPT was better than previously reported from TB-endemic areas, with 76% of the children completing at least 6 months of treatment, with more than 80% adherence.