Sustainability and impact of an intervention to improve initiation of tuberculosis preventive treatment: results from a follow-up study of the ACT4 randomized trial

Background

In a cluster randomized trial (clinicaltrials.gov: NCT02810678) a flexible but comprehensive health system intervention significantly increased the number of household contacts (HHC) identified and started on tuberculosis preventive treatment (TPT). A follow-up study was conducted one year later to test the hypotheses that these effects were sustained, and were reproducible with a simplified intervention.

Methods

We conducted a follow-up study from May 1, 2018 until April 30, 2019, as part of a multinational cluster randomized trial. Eight sites in 4 countries that had received the intervention in the original trial received no further intervention; eight other sites in the same countries that had not received the intervention (control sites in the original trial) now received a simplified version of the intervention. This consisted of repeated local evaluation of the Cascade of care for TB infection, and stakeholder decision making. The number of HHC identified and starting TPT were repeatedly measured at all 16 sites and expressed as rates per 100 newly diagnosed index TB patients. The sustained effect of the original intervention was estimated by comparing these rates after the intervention in the original trial with the last 6 months of the follow-up study. The reproducibility was estimated by comparing the pre-post intervention changes in rates at sites receiving the original intervention with the pre-post changes in rates at sites receiving the later, simplified intervention.

Findings

With regard to the sustained impact of the original intervention, compared to the original post-intervention period, the number of HHC identified and treated per 100 newly diagnosed TB patients was 10 more (95% confidence interval: 84 fewer to 105 more), and 1 fewer (95% CI: 22 fewer to 20 more) respectively up to 14 months after the end of the original intervention. With regard to the reproducibility of the simplified intervention, at sites that had initially served as control sites, the number of HHC identified and treated per 100 TB patients increased by 33 (95% CI: -32, 97), and 16 (-69, 100) from 3 months before, to up to 6 months after receiving a streamlined intervention, although differences were larger, and significant if the post-intervention results were compared to all pre-intervention periods.

Interpretation

Up to one year after it ended, a health system intervention resulted in sustained increases in the number of HHC identified and starting TPT. A simplified version of the intervention was associated with non-significant increases in the identification and treatment of HHC. Inferences are limited by potential bias due to other temporal effects, and the small number of study sites.

Funding

Funded by the Canadian Institutes of Health Research (Grant number 143350).

Experiences with latent TB cascade of care strengthening for household contacts in Calgary, Canada

SETTING

Identification, assessment, and treatment of latent TB infection (LTBI), collectively known as the LTBI cascade of care, is critical for TB prevention.

OBJECTIVE

The objective of this research, conducted within the ACT4 trial, was to assess and strengthen the LTBI cascade of care for household contacts at Calgary TB Services, a clinic serving a predominately foreign-born population in Western Canada.

DESIGN

Baseline assessment consisted of a retrospective LTBI cascade analysis of 32 contact investigations, and questionnaires administered to patients and health care workers. Four solutions were implemented in response to identified gaps. Solution impact was measured for 6 months using descriptive statistics.

RESULTS

Pre-implementation, 56% of household contacts initiated treatment. Most contacts were lost to care because the tuberculin skin test (TST) was not initiated, or physicians did not recommend treatment. Evening clinics, a patient education pamphlet, a nursing workshop, and treatment recommendation guidelines were implemented. Post-implementation, losses due to LTBI treatment non-recommendation were reduced; however, the overall proportion of household contacts initiating treatment did not increase.

CONCLUSION

Close engagement between researchers and TB programmes can reduce losses in the LTBI cascade. To see sustained improvement in overall outcomes, long-term engagement and data collection for ongoing problem-solving are required.

The respiratory microbiome and nontuberculous mycobacteria: an emerging concern in human health

Nontuberculous mycobacteria (NTM) are diverse microbial species encompassing commensals and pathogens with the ability to cause pulmonary disease in both immunocompetent and immunocompromised individuals. In contrast to Mycobacterium tuberculosis, which has seen a reduction in disease rates in developed countries, the incidence and prevalence of NTM disease is increasing. NTM are difficult to treat with standard antimicrobial regimens and may contain both virulence and antibiotic-resistance genes with potential for pathogenicity. With the advent of molecular techniques, it has been elucidated that these organisms do not reside in isolation and are rather part of a complex milieu of microorganisms within the host lung microbiome. Over the last decade, studies have highlighted the impact of the microbiome on host immunity, metabolism and cell-cell communication. This recognition of a broader community raises the possibility that the microbiome may disrupt the balance between infection and disease. Additionally, NTM disease progression and antimicrobial therapy may affect the healthy steady state of the host and function of the microbiome, contributing to further dysbiosis and clinical deterioration. There have been limited studies assessing how NTM may influence the relationship between microbiome and host. In this review, we highlight available studies about NTM and the microbiome, postulate on virulence mechanisms by which these microorganisms communicate and discuss implications for treatment.

Interventions to reduce losses in the cascade of care for latent tuberculosis: a systematic review and meta-analysis

BACKGROUND: Losses can occur throughout the latent tuberculosis infection (LTBI) cascade of care. This can result in suboptimal rates of effective treatment for LTBI. We conducted a systematic review and meta-analysis to estimate the effect of different interventions to reduce losses in the LTBI cascade before treatment completion.METHODS: We searched several databases for articles reporting outcomes for interventions designed to strengthen the LTBI cascade. We included papers published in English from January 1990 until February 2018. Where possible, estimates were pooled using random-effects meta-analysis.RESULTS: We identified 30 studies that evaluated 32 different interventions aimed at reducing losses in the LTBI cascade. In pooled analysis, interventions that improved completion of cascade steps included patient incentives (respectively 42 [95% CI 34-51] and 48 [95% CI 15-81] additional patients completing initial assessment and medical evaluation per 100 starting); health care worker education (28 [95% CI 4-52] additional patients initiating initial assessment per 100 identified; home visits (additional 13 [95% CI 4-21] patients completing initial assessment per 100 starting); digital solutions (additional 11 [95% CI 4-21] patients initiating initial assessment per 100 identified); and patient reminders (additional 7 [95% CI 0.3-13] patients completing initial assessment per 100 starting). Several other interventions reduced losses at specific cascade steps, but evidence for these interventions came from single studies and could not be pooled.CONCLUSIONS: Although there is limited evidence that any single intervention significantly improves the LTBI cascade, many studies provide information about effective ways to strengthen it.

Solutions to improve the latent tuberculosis Cascade of Care in Ghana: a longitudinal impact assessment

Background

Loss of patients in the latent tuberculosis infection (LTBI) cascade of care is a major barrier to LTBI management. We evaluated the impact and acceptability of local solutions implemented to strengthen LTBI management of household contacts (HHCs) at an outpatient clinic in Ghana.

Methods

Local solutions to improve LTBI management were informed by a baseline evaluation of the LTBI cascade and questionnaires administered to index patients, HHCs, and health care workers at the study site in Offinso, Ghana. Solutions aimed to reduce patient costs and improve knowledge. We evaluated the impact and acceptability of the solutions. Specific objectives were to: 1) Compare the proportion of eligible HHCs completing each step in the LTBI cascade of care before and after solution implementation; 2) Compare knowledge, attitude, and practices (KAP) before and after solution implementation, based on responses of patients and health care workers (HCW) to structured questionnaires; 3) Evaluate patient and HCW acceptability of solutions using information obtained from these questionnaires.

Results

Pre and Post-Solution LTBI Cascades included 58 and 125 HHCs, respectively. Before implementation, 39% of expected < 5-year-old HHCs and 66% of ≥5-year-old HHCs were identified. None completed any further cascade steps. Post implementation, the proportion of eligible HHCs who completed identification, assessment, evaluation, and treatment initiation increased for HHCs < 5 to 94, 100, 82, 100%, respectively, and for HHCs ≥5 to 96, 69, 67, 100%, respectively. Pre and Post-Solutions questionnaires were completed by 80 and 95 respondents, respectively. Study participants most frequently mentioned financial support and education as the solutions that supported LTBI management.

Conclusion

Implementation of locally selected solutions was associated with an increase in the proportion of HHCs completing all steps in the LTBI cascade. Tuberculosis programs should consider prioritizing financial support, such as payment for chest x-rays, to support LTBI cascade completion.

Using a quality improvement approach to improve care for latent tuberculosis infection

INTRODUCTION

Latent tuberculosis infection (LTBI) management is recognized as a key component of the World Health Organization End Tuberculosis Strategy. The term 'cascade of care in LTBI' has recently been used to refer to the process of LTBI management from identification of persons who may have LTBI to completion of treatment. Large gaps throughout the LTBI cascade of care have been identified. Areas covered: We have reviewed quality improvement (QI) as a potential approach for systematically improving gaps within the LTBI cascade of care. QI principles and approaches were reviewed, as well as the determinants of losses and evidence for solutions (interventions) within the LTBI cascade of care. An example of QI application in LTBI management is described. Expert commentary: Improving LTBI care at the magnitude required to reach the End TB Strategy goals will require systematic and context specific improvements at all steps in the cascade of care in LTBI. A continuous QI approach based on systems thinking, use of locally gathered data, and an iterative learning process can facilitate the process required to make the necessary improvements.