Background

We aimed to determine the extent to which emerging evidence and changing guidelines regarding timing of antiretroviral therapy (ART) among human immunodeficiency virus (HIV)-infected patients with tuberculosis influenced "real-world" clinical practice in Uganda.

Methods

We evaluated ART-naive, HIV-infected adults starting tuberculosis therapy at 2 HIV clinics in Uganda between 26 August 2006 and 29 September 2012. We used multivariate regression to calculate associations between 4 calendar periods reflecting publication of seminal clinical studies or changes in guidelines and timing of ART after tuberculosis therapy initiation.

Results

For patients with CD4 counts <50 cells/µL, the fraction starting ART within 14 and 30 days of initiating tuberculosis therapy increased from 7% to 14% and from 14% to 86% over the period of observation. The fraction of patients with CD4 counts >50 cells/µL starting ART within 60 days increased from 16% to 28%. After adjustment for sociodemographic factors, when comparing the most recent with the earliest calendar period, the rate of ART initiation increased by 4.57-fold (95% confidence interval [CI], 1.76-fold to 11.86-fold) among patients with baseline CD4 counts ≤ 50 cells/µL and by 5.43-fold (95% CI, 3.16- fold to 9.31-fold) among those with baseline CD4 counts >50 cells/µL.

Conclusions

We observed large changes in clinical practice during a period of emerging data and changing guidelines among HIV-infected patients with tuberculosis. Nonetheless, a significant proportion of individuals with higher CD4 cell counts do not start ART within recommended time frames. Targeted dissemination and implementation efforts are still needed to achieve target levels in practice.

Point-of-care C-reactive protein (POC CRP) testing is a potential tuberculosis (TB) screening tool for people living with HIV (PLHIV). Unlike lab-based assays, POC assays do not routinely adjust CRP levels for hematocrit, potentially resulting in TB screening status misclassification. We compared the diagnostic accuracy of unadjusted and hematocrit-adjusted POC CRP for culture-confirmed TB among PLHIV with CD4 cell-count ≤350 cells/uL initiating antiretroviral therapy (ART) in Uganda. We prospectively enrolled consecutive adults, measured POC CRP (Boditech; normal <8 mg/L), collected two spot sputum specimens for comprehensive TB testing, and extracted pre-ART hematocrit from clinic records. Of the 605 PLHIV included, hematocrit-adjusted POC CRP had similar sensitivity (80% vs 81%, difference +1% [95% CI -3 to +5], P= 0.56) and specificity (71% vs 71%, difference 0% [95% CI -1 to +1], P= 0.56) for culture-confirmed TB, relative to unadjusted POC CRP. When used for TB screening, POC CRP may not require adjustment for hematocrit. However, larger studies may be required if differences close to the clinically meaningful threshold are to be detected.

Background

People living with HIV (PLHIV) have an increased risk of developing active tuberculosis (TB). To reduce the burden of TB among PLHIV, the World Health Organization (WHO) recommends systematic TB screening followed by (1) confirmatory TB testing for all who screen positive and (2) TB preventive therapy (TPT) for all TPT-eligible PLHIV who screen negative. Symptom-based screening remains the standard of care in most high TB burden settings, including Uganda. Despite having high sensitivity for active TB among antiretroviral-naïve PLHIV, symptom screening has poor specificity; as such, many high-risk PLHIV without active TB are not referred for TPT. C-reactive protein (CRP) is a promising alternative strategy for TB screening that has comparable sensitivity and higher specificity than symptom screening, and was endorsed by WHO in 2021. However, the impact of CRP-based TB screening on TB burden for PLHIV remains unclear.

Methods

TB SCRIPT (TB Screening Improves Preventive Therapy Uptake) is a phase 3, multi-center, single-blinded, individual (1:1) randomized controlled trial evaluating the effectiveness of CRP-based TB screening on clinical outcomes of PLHIV. The trial aims to compare the effectiveness of a TB screening strategy based on CRP levels using a point-of-care (POC) assay on 2-year TB incidence and all-cause mortality (composite primary trial endpoint) and prevalent TB case detection and uptake of TPT (intermediate outcomes), relative to symptom-based TB screening (current practice).

Discussion

This study will be critical to improving selection of eligible PLHIV for TPT and helping guide the scale-up and integration of TB screening and TPT activities. This work will enable the field to improve TB screening by removing barriers to TPT initiation among eligible PLHIV, and provide randomized evidence to inform and strengthen WHO guidelines.

Trial registration

ClinicalTrials.gov NCT04557176. Registered on September 21, 2020.

Background

Interventions to improve performance of global programs in the HIV cascade of care are widespread and increasing the focus of implementation science. At present, however, there is no clear consensus on how to conceptualize their improvement at the program level. The commonly used measures of association, based on ratios of probabilities (or odds), have well-known defects in public health applications. They yield large effect sizes even when the absolute effects, and therefore the public health impact, are small. On the other hand, risk differences create problems because settings with higher baseline values are penalized. We aim to examine ways of quantifying improvement in each health center of a cluster-randomized trial in Uganda to accelerate antiretroviral therapy initiation among HIV-infected adults.

Methods

We formalize the concept of the 'improvement index,' defined as the fraction of gaps closed as a metric of improvement, and suggest that it has unique features and strengths when compared to risk ratios and risk differences.

Results

Overall agreement between the different indices was not high, especially among health centers that were among the top 5 or 10. However, all ranking showed broad similarities at the far ends of the spectrum. On scatter plots, there was a positive linear relationship between the metrics, and the Bland Altman (B-A) plots were in agreement.

Conclusion

The improvement index can be used as an alternative measure of association in implementation science interventions. It can be useful for public health purposes as it demonstrates how much can be covered from the baseline.

A 12-dose weekly regimen of rifapentine plus isoniazid (3HP) is recommended for the prevention of active tuberculosis (TB); however, it is unclear whether 3HP should be provided by directly observed therapy (DOT) or self-administered therapy (SAT). In addition, the introduction of patient informed choice between delivery modalities may have a positive impact on factors leading to treatment completion. The authors randomized 252 participants with HIV to a hypothetical scenario of providing preventive therapy by either DOT or an informed choice between DOT and SAT. Out of 104 participants who were randomized to a choice between DOT and SAT, 103 chose therapy by SAT. Participants rated their level of confidence and intention to complete therapy. Compared to those assigned to the DOT scenario, patients assigned to the choice scenario expressed greater confidence and intention to complete preventive therapy. Convenience and travel required to complete 3HP therapy were important factors in deciding between delivery modalities. Those assigned to DOT identified more barriers to completing therapy than those given a choice. Empowering patients to make informed decisions about how they receive TB preventive therapy may improve completion rates.

Background

In Africa, human immunodeficiency virus (HIV)-infected patients who present to care with CD4 levels >350 cells/µL (ie, current antiretroviral treatment thresholds) are often thought to be poorly retained in care, but most estimates do not account for outcomes among patients lost to follow-up.

Methods

We evaluated HIV-infected adults who had made a visit in the last 2.5 years in a program in Uganda. We identified a random sample of patients lost to follow-up (9 months without a visit). Ascertainers sought patients in the community in this sample and outcomes were incorporated into revised survival estimates of mortality and retention for the clinic population using a probability weight.

Results

Of 6473 patients, (29% male, median age 29 years, median CD4 count 550 cells/µL), 1294 (20%) became lost to follow-up over 2.5 years. Two hundred seven (16%) randomly selected lost patients were sought, and in 175 (85%) vital status was ascertained. In 19 of 175 (11%), the patient had died. Of the 156 (89%) alive, 74 (47%) were interviewed in person, and 38 of 74 (51%) reported HIV care elsewhere, whereas 36 of 74 (49%) were not in care. Application of weights derived from sampling found that at 2.5 years, retention among patients who enrolled with CD4 levels >350 cells/µL was 88.2% and mortality was 2.5%. Lower income, unemployment, and rural residence were associated with failure to be retained.

Conclusions

Retention in patients entering care with high CD4 counts under routine program conditions in Africa is high in a Ugandan care program and may be systematically underestimated in many other settings.

Objectives

In resource-limited settings, mortality in the initial months following antiretroviral therapy (ART) initiation remains unacceptably high. Novel tools to identify patients at highest risk of poor outcomes are needed. We evaluated whether elevated C-reactive protein (CRP) concentrations predict poor outcomes among people living with HIV (PLWH) initiating ART.

Methods

We enrolled and followed for 3-months consecutive PLWH with pre-ART CD4 T-cell counts 350 cells/μl or less initiating ART from two HIV clinics in Uganda. Pre-ART CRP concentrations were measured from capillary blood using a point-of-care (POC) assay. After excluding patients with prevalent tuberculosis - the leading cause of HIV death - we measured 3-month mortality rates using Kaplan-Meier curves, used Cox regression to compare differences in survival, and used logistic regression to compare differences in the odds of opportunistic infections, between patients with and without elevated POC CRP (≥8 mg/l).

Results

Of 1293 patients included [median CD4 T-cell count 181 (interquartile range 82-278)], 23 (1.8%) died within 3 months, including 19 of 355 (5.4%) with elevated POC CRP and four of 938 (0.4%) with nonelevated POC CRP. Eighty-six (6.7%) patients were diagnosed with opportunistic infections, including 39 of 355 (11.0%) with elevated POC CRP and 47 of 938 (5.0%) with nonelevated POC CRP. Elevated POC CRP was associated with mortality (adjusted hazard ratio 10.87, 95% confidence interval 3.64-32.47) and opportunistic infection (adjusted odds ratio 1.95, 95% confidence interval 1.23-3.07).

Conclusion

Among PLWH with advanced HIV, elevated pre-ART POC CRP concentrations are associated with early mortality and opportunistic infections. Pre-ART POC CRP testing may reduce mortality by identifying patients at high risk for poor outcomes.

Objective

To assess the prevalence of severe transaminitis precluding tuberculosis (TB) preventive therapy (TPT) initiation for people with HIV (PWH) in a high TB/HIV burden setting.

Design/methods

We conducted a secondary analysis of data from a prospective cohort study of PWH with pre-antiretroviral therapy (ART) CD4 + counts 350 cells/μl or less undergoing systematic TB screening from two HIV clinics in Uganda. For this analysis, we excluded patients with culture-confirmed TB and patients without aspartate transaminase (AST) or alanine transaminase (ALT) levels measured within three months of enrollment. We compared the proportion of patients with any transaminitis (AST or ALT greater than one times the upper limit of normal ULN) and severe transaminitis (AST or ALT >3 times ULN) for patients screening negative for TB by symptoms and for those screening negative by C-reactive protein (CRP). We also assessed the proportion of patients with transaminitis by self-reported alcohol consumption.

Results

Among 313 participants [158 (50%) women, median age 34 years (IQR 27-40)], 75 (24%) had any transaminitis and six (2%) had severe transaminitis. Of 32 of 313 (10%) who screened negative for TB by symptoms, none had severe transaminitis. In contrast, six-times more PWH screened negative for TB by CRP (194 of 313; 62%), of whom only four (2.1%) had severe transaminitis. Differences in the proportion with any and severe transaminitis according to alcohol consumption were not statistically significant.

Conclusion

Prevalence of severe transaminitis was low among PWH without culture-confirmed TB in this setting, and is therefore, unlikely to be a major barrier to scaling-up TPT.

Background

Tuberculosis (TB) risk varies among different HIV subgroups, potentially impacting intensified case finding (ICF) performance. We evaluated the performance of the current ICF algorithm [symptom screening, followed by Xpert MTB/RIF (Xpert) testing] in 2 HIV subgroups and evaluated whether ICF performance could be improved if TB screening was based on C-reactive protein (CRP) concentrations.

Methods

We enrolled consecutive adults with CD4 counts ≤350 cells/µL initiating antiretroviral therapy and performed symptom screening, CRP testing using a low-cost point-of-care (POC) assay, and collected sputum for Xpert testing. We compared the yield and efficiency of the current ICF algorithm to POC CRP-based ICF among patients new to HIV care and patients engaged in care.

Results

Of 1794 patients, 126/1315 (10%) new patients and 21/479 (4%) engaged patients had Xpert-positive TB. The current ICF algorithm detected ≥98% of all TB cases in both subgroups but required ≥85% of all patients to undergo Xpert testing. POC CRP-based ICF halved the proportion of patients in both subgroups requiring Xpert testing relative to the current ICF algorithm and had lower yield among patients engaged in care [81% vs. 100%, difference -19% (95% confidence interval: -41 to 3)]. Among patients new to care, POC CRP-based ICF had similar yield as the current ICF algorithm [93% vs. 98%, difference -6% (95% confidence interval: -11 to 0)].

Conclusions

Among patients new to care, POC CRP-based screening can improve ICF efficiency without compromising ICF yield, whereas symptom-based screening may be necessary to maximize ICF yield among patients engaged in care.