Drop-offs in the isoniazid preventive therapy cascade among children living with HIV in western Kenya, 2015-2019

Biomarker-confirmed suboptimal adherence to isoniazid preventive therapy among children with HIV in western Kenya

OBJECTIVES

The aim of this study was to assess the level and correlates of biomarker-confirmed adherence to isoniazid (INH) preventive therapy (IPT) among children with HIV (CLHIV).

DESIGN

This prospective cohort study assessed adherence among CLHIV on IPT in public sector HIV clinics from 2019 through 2020.

METHODS

Adherence was assessed by pill counts or caregiver or self-reports, and urine biomarkers (in-house dipstick and Isoscreen). Both urine biomarker tests detect INH metabolites within 48 h of ingestion. Consistent adherence was defined as having positive results on either biomarker at all visits. Correlates of biomarker-confirmed nonadherence at each visit were evaluated using generalized estimating equations. The in-house dipstick was validated using Isoscreen as the reference.

RESULTS

Among 97 CLHIV on IPT with adherence assessments, median age was 10 years (IQR 7-13). All were on ART at IPT initiation (median duration 46 months [IQR 4-89]); 81% were virally suppressed (<1000 copies/ml). At all visits, 59% ( n  = 57) of CLHIV reported taking at least 80% of their doses, while 39% ( n  = 38) had biomarker-confirmed adherence. Viral nonsuppression (adjusted risk ratio [aRR] = 1.65; 95% confidence interval [95% CI] 1.09-2.49) and the sixth month of IPT use (aRR = 2.49; 95% CI 1.34-4.65) were independent correlates of biomarker-confirmed nonadherence at each visit. Sensitivity and specificity of the in-house dipstick were 98.1% ( 94.7 - 99.6%) and 94.7% ( 88.1 - 98.3%) , respectively, versus Isoscreen.

CONCLUSION

Biomarker-confirmed adherence to IPT was sub-optimal and was associated with viral nonsuppression and duration of IPT. Urine dipstick testing may be useful in assessing adherence to IPT in clinical care.

Tuberculosis Preventative Therapy Initiation and Completion Among Adolescents and Young Adults Living With HIV in Kenya

BACKGROUND

Tuberculosis is the leading cause of death among adolescents and young adults living with HIV (YWHIV) and their heightened risk warrants deeper understanding of utilization of tuberculosis-prevention measures within HIV care.

SETTING

Retrospective study using clinic surveys and medical record data from 86 Kenyan HIV clinics.

METHODS

Clinic surveys obtained information on tuberculosis preventive therapy (TPT) services. Medical records of YWHIV were abstracted. Bivariate and multivariate analyses used generalized linear models to determine individual-level and clinic-level cofactors of TPT initiation and completion.

RESULTS

Among 10,328 eligible YWHIV, 4337 (42.0%) initiated TPT. Of 3295 with ≥6 months follow-up, 1774 (53.8%) completed TPT. A lower patient-to-staff ratio was a clinic-level cofactor of TPT initiation ( P = 0.044) and completion ( P = 0.004); designated adolescent areas were associated with TPT initiation {prevalence ratio 2.05 [95% confidence interval (CI): 1.46 to -2.88]}. Individual cofactors of TPT initiation included younger age at HIV-care enrollment [relative risk (RR) 0.85 (95% CI: 0.80 to 0.90)] and antiretroviral therapy (ART) duration [1-2 vs. <1 year RR 1.31 (95% CI: 1.18 to 1.45)]. TPT completion was associated with younger age [RR 0.91 (95% CI: 0.85 to 0.98)] and ART duration [2-5 vs. <1 year RR 1.27 (95% CI: 1.03 to 1.57)]. In multivariate models, TPT initiation was associated with younger age and ART duration [1-2 vs. 1 year; adjusted RR 1.30 (95% CI: 1.16 to 1.46)] and TPT completion with ART duration [2-5 vs. 1 year adjusted RR 1.23 (95% CI: 0.99 to 1.52)].

CONCLUSION

Over half of YWHIV did not initiate and >40% did not complete TPT, with distinct clinic-level and individual-level cofactors. Approaches to enhance adolescent-friendly infrastructure and support older YWHIV are necessary to improve TPT use.