Isoniazid preventive therapy in correctional facilities: a systematic review

Tuberculosis (TB) remains a major cause of morbidity and mortality worldwide and the main cause of death in correctional facilities in middle- and low-income countries. Due to the closed environment and the concentration of individuals with TB-related risk factors, effective measures are required to control TB in such settings. Isoniazid preventive therapy (IPT) represents an effective and cost-effective measure. Despite international recommendations that IPT be integral to TB control, it is seldom deployed. A systematic review of interventions used to assess IPT initiation and completion in correctional facilities was conducted using published studies from two biomedical databases and relevant keywords. Additional references were reviewed, resulting in 18 eligible studies. Most (72%) studies were conducted in the United States and in jail settings (60%), with the main objective of improving completion rates inside the facility or after release. Studies that provided data about initiation and completion rates showed poor success in correctional facilities. Adverse consequences and treatment interruption ranged from 1% to 55% (median 5%) in reported studies; hepatotoxicity was the most prevalent adverse reaction. Despite its accelerating effect on the development of active TB, information on human immunodeficiency virus (HIV) status was provided in only half of the studies. Among the four studies where IPT effectiveness was assessed, the results mirror those described in community settings. Future studies require thorough assessments of IPT initiation and completion rates and adverse effects, particularly in low- and middle-income countries and where comorbid viral hepatitis may contribute significantly to outcomes, and in settings where TB and HIV are more endemic.