Completion of 6-mo isoniazid preventive treatment among eligible under six children: A cross-sectional study, Lagos, Nigeria

BACKGROUND: Nigeria is one of the thirty high burden countries with significant contribution to the global childhood tuberculosis epidemic. Tuberculosis annual risk for children could be as high as 4% particularly in high tuberculosis (TB) prevalent communities. Isoniazid (INH) Preventive Therapy has been shown to prevent TB incidence but data on its implementation among children are scarce. AIM: To determine the completion of INH among under six children that were exposed to adults with smear positive pulmonary TB in Lagos, Nigeria. METHODS: This was a hospital-based retrospective cross-sectional review of 265 medical records of eligible children < 6 years old enrolled for INH across 32 private hospitals in Lagos, Nigeria. The study took place between July and September 2020. Data was collected on independent variables (age, gender, type of facility, TB screening, dose and weight) and outcome variables (INH outcome and proportion lost to follow up across months 1-6 of INH treatment). RESULTS: About 53.8% of the participants were female, 95.4% were screened for TB and none was diagnosed of having TB. The participants’ age ranged from 1 to 72 mo with a mean of 36.01 ± 19.67 mo, and 40.2% were between the ages of 1-24 mo. Only 155 (59.2%) of the 262 participants initiated on INH completed the six-month treatment. Cumulatively, 107 (41.0%) children were lost to follow-up at the end of the sixth month. Of the cumulative 107 loss to follow-up while on INH, largest drop-offs were reported at the end of month 2, 52 (49%) followed by 20 (19%), 17 (16%), 11 (10.2%) and 7 (6.5%) at months 3, 4, 5 and 6 respectively. The analysis showed that there was no significant association between age, gender, type of facility and completion of INH treatment (P > 0.005). CONCLUSION: This study demonstrated suboptimal INH completion rate among children with only 6 out of 10 children initiated on INH who completed a 6-mo treatment in Lagos, Nigeria. The huge drop-offs in the first 2 mo of INH calls for innovative strategies such as the use of 60-d INH calendar that would facilitate reminder and early engagement of children on INH and their caregivers in care and across the entire period of treatment.