Smoked drug use in patients with TB is associated with higher bacterial burden

The impact of alcohol and illicit substance use on the pharmacokinetics of first-line TB drugs

BACKGROUND

In South Africa, an estimated 11% of the population have high alcohol use, a major risk factor for TB. Alcohol and other substance use are also associated with poor treatment response, with a potential mechanism being altered TB drug pharmacokinetics.

OBJECTIVES

To investigate the impact of alcohol and illicit substance use on the pharmacokinetics of first-line TB drugs in participants with pulmonary TB.

METHODS

We prospectively enrolled participants ≥15 years old, without HIV, and initiating drug-susceptible TB treatment in Worcester, South Africa. Alcohol use was measured via self-report and blood biomarkers. Other illicit substances were captured through a urine drug test. Plasma samples were drawn 1 month into treatment pre-dose, and 1.5, 3, 5 and 8 h post-dose. Non-linear mixed-effects modelling was used to describe the pharmacokinetics of rifampicin, isoniazid, pyrazinamide and ethambutol. Alcohol and drug use were tested as covariates.

RESULTS

The study included 104 participants, of whom 70% were male, with a median age of 37 years (IQR 27-48). Alcohol use was high, with 42% and 28% of participants having moderate and high alcohol use, respectively. Rifampicin and isoniazid had slightly lower pharmacokinetics compared with previous reports, whereas pyrazinamide and ethambutol were consistent. No significant alcohol use effect was detected, other than 13% higher ethambutol clearance in participants with high alcohol use. Methaqualone use reduced rifampicin bioavailability by 19%.

CONCLUSION

No clinically relevant effect of alcohol use was observed on the pharmacokinetics of first-line TB drugs, suggesting that poor treatment outcome is unlikely due to pharmacokinetic alterations. That methaqualone reduced rifampicin means dose adjustment may be beneficial.

Piloting Siyakhana: A community health worker training to reduce substance use and depression stigma in South African HIV and TB care

South Africa has one of the highest rates of HIV/tuberculosis (TB) co-infection, and poor engagement in HIV/TB care contributes to morbidity and mortality. In South Africa, community health workers (CHWs) are tasked with re-engaging patients who have dropped out of HIV/TB care. CHWs have described substantial challenges with substance use (SU) and depression among their patients, while patients have described CHW stigma towards SU and depression as barriers to re-engagement in care. Yet, CHWs receive little-to-no training on SU or depression. Therefore, we piloted Siyakhana, a brief CHW training to reduce stigma related to SU and depression while improving skills for re-engaging these patients in HIV and/or TB care. This study evaluated the preliminary effectiveness (stigma towards SU and depression; clinical competence assessed via roleplay) and implementation (quantitative ratings of feasibility, acceptability, appropriateness, adoption; semi-structured written qualitative feedback) of Siyakhana among CHWs and supervisors (N = 17) at pre- and post-training assessments. SU stigma significantly decreased (F(1,16) = 18.94, p < 0.001, ηp2 = 0.54). Depression stigma was lower than SU stigma at both timepoints and did not significantly decrease after training. CHW clinical competency towards patients with SU/depression significantly improved (t(11) = -3.35, p = 0.007, d = 1.00). The training was rated as feasible, acceptable, appropriate, and likely to be adopted by CHWs and their supervisors. Nonjudgmental communication was commonly described as the most useful training component. Based on this pilot, the training is being refined and evaluated in a larger randomized stepped-wedge clinical trial.

A retrospective cohort analysis of treatment outcomes of patients with tuberculosis who used substances in Tel Aviv, Israel

AIMS

To outline the demographic, clinical, laboratory characteristics, and treatment outcomes of tuberculosis (TB) patients who used substances.

METHODS

This retrospective cohort study compared 50 TB patients who used substances with a matched random sample of 100 TB patients who did not use substances between 2007 and 2017. Treatment failure was defined as a sputum smear or culture that tested positive after 5 months of treatment, loss to follow-up, unevaluated patients, or death.

RESULTS

TB patients who used substances were typically younger, experienced homelessness, smokers, and had fewer chronic diseases than those who did not use substances. They also were hospitalized for longer periods, their treatment durations were longer, had higher rates of multidrug resistant strains, increased rates of treatment failure, and higher mortality. Individuals whose treatment failed predominantly originated from the former Soviet Union, experienced homelessness, and had chronic diseases compared with those whose treatment was successful. In the multivariate analysis, homelessness [odds ratios (OR) = 6.7], chronic diseases (OR = 12.4), and substance use (OR = 4.0) were predictors of treatment failures.

CONCLUSIONS

TB patients who used substances were more likely to have treatment failure. Targeted interventions, including early diagnosis and enhanced support during treatment, are essential to achieve treatment success in this vulnerable population, in addition to TB-alcohol/drug collaborative activities.

Community health worker training to reduce mental health and substance use stigma towards patients who have disengaged from HIV/TB care in South Africa: protocol for a stepped wedge hybrid type II pilot implementation trial

BACKGROUND

South Africa has deployed community health workers (CHWs) to support individuals to enter and stay in HIV/TB care. Although CHWs routinely encounter patients with mental health (particularly depression) and substance use (SU) conditions that impact their engagement in HIV/TB care, CHWs are rarely trained in how to work with these patients. This contributes to mental health and SU stigma among CHWs, a known barrier to patient engagement in care. Mental health and SU training interventions could reduce CHW stigma and potentially improve patient engagement in care, but evidence of the feasibility, acceptability, and preliminary effectiveness of these interventions is scarce. Therefore, we designed a hybrid type 2 effectiveness-implementation pilot trial to evaluate the implementation and preliminary effectiveness of a CHW training intervention for reducing depression and SU stigma in the Western Cape, South Africa.

METHODS

This stepped wedge pilot trial will engage CHWs from six primary care clinics offering HIV/TB care. Clinics will be block randomized into three-step cohorts that receive the intervention at varying time points. The Siyakhana intervention involves 3 days of training in depression and SU focused on psychoeducation, evidence-based skills for working with patients, and self-care strategies for promoting CHW wellness. The implementation strategy involves social contact with people with lived experience of depression/SU during training (via patient videos and a peer trainer) and clinical supervision to support CHWs to practice new skills. Both implementation outcomes (acceptability, feasibility, fidelity) and preliminary effectiveness of the intervention on CHW stigma will be assessed using mixed methods at 3- and 6-month follow-up assessments.

DISCUSSION

This trial will advance knowledge of the feasibility, acceptability, and preliminary effectiveness of a CHW training for reducing depression and SU stigma towards patients with HIV and/or TB. Study findings will inform a larger implementation trial to evaluate the longer-term implementation and effectiveness of this intervention for reducing CHW stigma towards patients with depression and SU and improving patient engagement in HIV/TB care.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05282173. Registered on 7 March 2022.