Correlates of default from anti-tuberculosis treatment: a case study using Kenya's electronic data system

Quantifying non-adherence to anti-tuberculosis treatment due to early discontinuation: a systematic literature review of timings to loss to follow-up

BACKGROUND

The burden of non-adherence to anti-tuberculosis (TB) treatment is poorly understood. One type is early discontinuation, that is, stopping treatment early. Given the implications of early discontinuation for treatment outcomes, we undertook a systematic review to estimate its burden, using the timing of loss to follow-up (LFU) as a proxy measure.

METHODS

Web of Science, Embase and Medline were searched up to 14 January 2021 using terms covering LFU, TB and treatment. Studies of adults (≥ 18 years) on the standard regimen for drug-sensitive TB reporting the timing of LFU (WHO definition) were included. A narrative synthesis was conducted and quality assessment undertaken using an adapted version of Downs and Black. Papers were grouped by the percentage of those who were ultimately LFU who were LFU by 2 months. Three groups were created: <28.3% LFU by 2 months, ≥28.3-<38.3%, ≥38.3%). The percentage of dose-months missed due to early discontinuation among (1) those LFU, and (2) all patients was calculated.

RESULTS

We found 40 relevant studies from 21 countries. The timing of LFU was variable within and between countries. 36/40 papers (90.0%) reported the percentage of patients LFU by the end of 2 months. 31/36 studies (86.1%) reported a higher than or as expected percentage of patients becoming LFU by 2 months. The percentage of dose-months missed by patients who became LFU ranged between 37% and 77% (equivalent to 2.2-4.6 months). Among all patients, the percentage of dose-months missed ranged between 1% and 22% (equivalent to 0.1-1.3 months).

CONCLUSIONS

A larger than expected percentage of patients became LFU within the first 2 months of treatment. These patients missed high percentages of dose months of treatment due to early discontinuation. Interventions to promote adherence and retain patients in care must not neglect the early months of treatment.

PROSPERO REGISTRATION NUMBER

CRD42021218636.

A qualitative exploration of tuberculosis patients who were lost to follow-up in Malaysia

BACKGROUND

Loss to follow-up (LTFU) is an unsuccessful treatment outcome for tuberculosis (TB) patients. In Malaysia, LTFU affects around 1 in 20 TB patients. Integration of qualitative research methods and evidence will provide a better understanding of LTFU and its underlying issues. In this study, we qualitatively explored TB patients' experiences in receiving treatment and their reasons for leaving TB care.

METHOD

In-depth interviews of 15 patients with a history of LTFU were conducted from January to September 2020. Interview guides were developed to explore TB patients' experiences while receiving treatment, including challenges faced and reasons for treatment interruption. Data were thematically analysed using the framework method.

RESULTS

We identified 11 emerging themes that occurred at four levels of interaction with TB patients. First, at the patient personal level, TB beliefs referring to patients' perception of illness and wellness, patients' perceived role of traditional and complementary medicine, and substance abuse were important. Second, the healthcare system and treatment factors that were highlighted included the organisation of care and treatment, interaction with healthcare professionals, particularly in communication and counselling, and TB medications' side effects. Third, structural factors including financial burden, logistical and transportation issues and work-related factors were identified to be barriers to treatment continuation. Fourth, the interpersonal level interaction of patients should not be neglected; this includes family relationships and support as well as peer influence.

CONCLUSION

Study findings put forth issues and challenges faced by TB patients while receiving treatment and underscore areas where actions can be taken. This will contribute to informing the development and implementation of future TB control strategies that are responsive to TB patients' needs and concerns, to effectively address LTFU and ensure better treatment completion rates among TB patients in Malaysia.

Longitudinal-Survival Models for Case-Based Tuberculosis Progression

Introduction: Tuberculosis (TB) disease continues to be responsible for a high global burden with an estimated 10 million people falling ill each year and an estimated 1.45 million deaths. Widely carried out analyses to utilize routine data coming from this disease, and well-established in literature, have paid attention to time-to-event with sputum smear results being considered only at baseline or even ignored. Also, logistic regression models have been used to demonstrate importance of sputum smear results in patient outcomes. A feature presented by this disease, however, is that each individual patient is usually followed over a period of time with sputum smear results being documented at different points of the treatment curve. This provides both repeated measures and survival times, which may require a joint modeling approach. This study aimed to investigate the association between sputum smear results and the risk of experiencing unfavorable outcome among TB patients and dynamically predict survival probabilities.

Method: A joint model for longitudinal and time-to-event data was used to analyze longitudinally measured smear test results with time to experiencing unfavorable outcome for TB patients. A generalized linear mixed-effects model was specified for the longitudinal submodel and cox proportional hazards model for the time-to-event submodel with baseline hazard approximated using penalized B-splines. The two submodels were then assumed to be related via the current value association structure. Bayesian approach was used to approximate parameter estimates using Markov Chain Monte Carlo (MCMC) algorithm. The obtained joint model was used to predict the subject's future risk of survival based on sputum smear results trajectories. Data were sourced from routinely collected TB data stored at National TB Program database.

Results: The average baseline age was 35 (SD: 15). Female TB patients constituted 36.42%. Patients with previous history of TB treatment constituted 6.38% (event: 15.25%; no event: 5.29%). TB/HIV co-infection was at 31.23% (event: 47.87%; no event: 29.20%). The association parameter 1.03 (CI[1.03,1.04]) was found to be positive and significantly different from zero, interpreted as follows: The estimate of the association parameter α = 1.033 denoted the log hazard ratio for a unit increase in the log odds of having smear positive results. HIV status (negative) 0.47 (CI [0.46,49]) and history of TB treatment (previously treated) (2.52 CI [2.41,2.63]), sex (female) (0.82 CI [0.78,0.84]), and body mass index (BMI) categories (severe malnutrition being reference) were shown to be statistically significant.

Conclusion: Sputum smear result is important in estimating the risk to unfavorable outcome among TB patients. Men, previously treated, TB/HIV co-infected and severely malnourished TB patients are at higher risk of unfavorable outcomes.

Under-reporting of sputum smear-positive tuberculosis cases in Kenya

BACKGROUND

Although an estimated three million tuberculosis (TB) cases worldwide are missed by national TB programs annually, the level of under-reporting of diagnosed cases in high TB burden settings is largely unknown.

OBJECTIVE

To quantify and describe under-reporting of sputum smear-positive TB cases in Kenya.

DESIGN

A national-level retrospective TB inventory study was conducted. All sputum smear-positive TB cases diagnosed by public or private laboratories during 1 April-30 June 2013 were extracted from laboratory registers in 73 randomly sampled subcounties and matched to TB cases in the national TB surveillance system (TIBU). Bivariate and multivariate analyses were conducted.

RESULTS

In the subcounties sampled, 715 of 3409 smear-positive TB cases in laboratory registers were not found in TIBU. The estimated level of under-reporting of smear-positive TB cases in Kenya was 20.7% (95%CI 18.4-23.0). Under-reporting was greatest in subcounties with a high TB burden. Unreported cases were more likely to be patients aged ⩾55 years, have scanty smear results, and be diagnosed at large facilities, private facilities, and facilities in high TB burden regions.

CONCLUSION

In Kenya, one fifth of smear-positive TB cases diagnosed during the study period went unreported, suggesting that the true TB burden is higher than reported. TB surveillance in Kenya should be strengthened to ensure all diagnosed TB cases are reported.

Risk factors for unfavourable treatment outcome among new smear-positive pulmonary tuberculosis cases in China

Setting: Three projects of the Fund for Innovative DOTS Expansion through Local Initiatives to Stop TB. Objectives: To assess unfavourable treatment outcomes (UTOs), including failure, died, loss to follow-up (LTFU), transferred out and unknown outcome, and to identify risk factors associated with UTOs. Design: This was a cross-sectional study using routine programme data. Results: Of 30 277 new smear-positive tuberculosis (TB) patients, 4261 (14.1%) had UTOs: 2048 (6.8%) LTFU, 1418 (4.7%) transferred out, 390 (1.3%) died, 340 (1.1%) failed and 65 (0.2%) had an unknown outcome. Risk factors for LTFU (including LTFU, transfer out and unknown outcome) were residing in Anhui, age > 55 years, service delay > 10 days, patient delay < 30 days, directly observed treatment (DOT) provided by a family member or others and unknown DOT provider. The outcome of 'died' was associated with residing in Shaanxi, age > 55 years, male sex, patient delay > 30 days and unknown DOT provider. 'Failed' was associated with having unlimited access to health services, patient delay of >30 days and unknown DOT provider. Conclusion: This study highlights the predominance of lost patients among UTOs. Patients with family members or other non-medical DOT providers or unknown DOT providers had a high risk of a UTO. There is an urgent need to address these service-related factors.