Prevalence and predictors of tuberculosis infection among people living with HIV in a high tuberculosis burden context
Authors: Njagi Lilian N. , Nduba Videlis , Mureithi Marianne , Mecha Jared O. 
Published: December 2022

Background

Tuberculosis (TB) disease is the leading cause of mortality among people living with the Human immunodeficiency virus (PLHIV). Interferon-gamma release assays (IGRAs) are approved for TB infection ascertainment. However, current IGRA data on the prevalence of TB infection in the context of near-universal access to antiretroviral therapy (ART) and widespread TB preventive therapy (TPT) implementation are lacking. We estimated the prevalence and determinants of TB infection among PLHIV within a high TB and HIV burden context.

Methods

This cross-sectional study included data from adult PLHIV age ≥ 18 years in whom QuantiFERON-TB Gold Plus (QFT-Plus) assay, an IGRA, was performed. TB infection was defined as a positive or indeterminate QFT-Plus test. Participants with TB and those who had previously used TPT were excluded. Regression analysis was performed to identify independent predictors of TB infection.

Results

Of 121 PLHIV with QFT-Plus test results, females were 74.4% (90/121), and the mean age was 38.4 (standard deviation [SD] 10.8) years. Overall, 47.9% (58/121) were classified as TB infection (QFT-Plus test positive and indeterminate results were 39.7% [48/121] and 8.3% [10/121], respectively), with mean ages of 38.7 (SD 10.30) vs 38.2 (SD 11.3) years, respectively (p=0.602). Being obese/overweight (body mass index ≥25; p=0.013, adjusted odds ratio (aOR) 2.90, 95% confidence interval [CI] 1.25–6.74) and ART usage for >3 years (p=0.013, aOR 3.99, 95% CI 1.55– 10.28) were independently associated with TB infection.

Conclusion

There was a high TB infection prevalence among PLHIV. A longer period of ART and obesity were independently associated with TB infection. The relationship between obesity/overweight and TB infection may be related to ART and immune reconstitution and requires further investigation. Given the known benefit of test-directed TPT among PLHIV never exposed to TPT, its clinical and cost implications for low and middle-income countries should be explored further.

KEY MESSAGES

What is already known on this topic

Among people living with HIV (PLHIV), the risk of progression to tuberculosis (TB) disease is higher with confirmed and untreated TB infection. Data on the prevalence of TB infection in the context of near-universal access to antiretroviral therapy (ART) and widespread TB preventive therapy (TPT) implementation are lacking in Africa.

What this study adds

This study provides evidence that the prevalence of TB infection remains high even in the context of near-universal ART and widespread TPT. ART use and obesity/overweight may be associated with TB infection.

How this study might affect research, practice or policy

This study should prompt larger studies to explore predictors of TB infection. TPT should remain as part of care for PLHIV on ART. A broader understanding of the clinical and cost implications of test-directed TPT for PLHIV in low and middle-income countries may better inform policy towards its recommendation.