Effectiveness of directly observed therapy (DOT) for tuberculosis: a review of multinational experience reported in 1990-2000

Delineating the factors associated with recurrence of tuberculosis in programmatic settings of rural health block, Himachal Pradesh, India

BACKGROUND

Tuberculosis (TB) recurrence observed to be an important event in its treatment and has future implications under national TB control efforts. The present study was carried out to assess the recurrence rate along with its risk factors among patients undergoing treatment for TB under Revised National TB Control Program (RNTCP).

MATERIAL AND METHODS

Total 204 patients in health block of district Una, Himachal Pradesh were studied using pretested structured interviewer-administered questionnaire. Along with univariate a non-hierarchal multi-way frequency analysis (MFA) was done to study the one and multi-way effects between the discrete variables included in a hypothesized model. The variables were under-nutrition, pulmonary TB, injecting drug use (IDU), multi-drug resistant (MDR) TB, and past TB (recurrent cases).

RESULTS

Total 29 cases (14.2%) had recurrence (17.7/100,000 population) with significantly high fraction for alternate residence (Recurrent: 50.0%, Non-recurrent: 47.4%; p = 0.001), Multi-drug resistance (MDR) TB (Recurrent: 13.8%, Non-recurrent: 2.3%; p = 0.003), and sputum negative patients (Recurrent: 51.7%, Non-recurrent: 14.5%; p = 0.000). Non-recurrent cases had significantly high fraction for sputum positive cases (Recurrent: 48.3%, Non-recurrent: 72.1%; p = 0.011), and extra-pulmonary TB (Recurrent: 00.0%, Non-recurrent: 13.4%; p = 0.036). MFA observed all significant one-way effects. Significant two-way effects were IDU and pulmonary TB (p = 0.001), MDR and past TB (p = 0.004), IDU and past TB (p = 0.019), and IDU and MDR-TB (p = 0.039).

CONCLUSION

Proportion of TB recurrence was expected with a significant difference between the history of change of residence, MDR-TB, pulmonary and extra-pulmonary nature of the disease. Hypothesized model observed with a significant association of IDU, pulmonary TB, MDR-TB and past TB.

DOTS for TB relapse in India: A systematic review

In India, under the Revised National Tuberculosis Control Program (RNTCP), the percentage of smear-positive re-treatment cases is high. The causes of re-treatment include relapse of the disease after successful completion of treatment, treatment failure, and default in treatment. RNTCP does not follow up the patients for any period of time after successful completion of treatment to determine whether they relapse. Given the high cost of treatment for each patient under RNTCP and the potential for spread of disease from these patients, it is crucial for the success of the program and control of the disease in the country to find out more about the reasons behind this. T0 o conduct a systematic review of literature and determine evidence regarding recurrence of TB after its successful treatment with standard short course chemotherapy under DOTS guidelines. T0 en databases were searched including Medline, Cochrane database, Embase and others and reference lists of articles. 255 papers resulted from these searches. Seven studies were finally included in the review after applying the inclusion, exclusion and quality assessment criteria. R0 elapse rate is high (almost 10%) in India which is higher than international studies. Majority of relapse cases present soon after completion of treatment (first six months). Risk factors for relapse included drug irregularity, initial drug resistance, smoking and alcoholism Sex and weight were not risk factors in India. The outcome of relapse cases put on treatment is positive but less effective than new cases. There are sound arguments and sketchy evidence that DOTS Category 2 treatment may not be adequate for retreatment patients.

Patients' costs and cost-effectiveness of tuberculosis treatment in DOTS and non-DOTS facilities in Rio de Janeiro, Brazil

BACKGROUND

Costs of tuberculosis diagnosis and treatment may represent a significant burden for the poor and for the health system in resource-poor countries.

OBJECTIVES

The aim of this study was to analyze patients' costs of tuberculosis care and to estimate the incremental cost-effectiveness ratio (ICER) of the directly observed treatment (DOT) strategy per completed treatment in Rio de Janeiro, Brazil.

METHODS

We interviewed 218 adult patients with bacteriologically confirmed pulmonary tuberculosis. Information on direct (out-of-pocket expenses) and indirect (hours lost) costs, loss in income and costs with extra help were gathered through a questionnaire. Healthcare system additional costs due to supervision of pill-intake were calculated considering staff salaries. Effectiveness was measured by treatment completion rate. The ICER of DOT compared to self-administered therapy (SAT) was calculated.

PRINCIPAL FINDINGS

DOT increased costs during the treatment phase, while SAT increased costs in the pre-diagnostic phase, for both the patient and the health system. Treatment completion rates were 71% in SAT facilities and 79% in DOT facilities. Costs per completed treatment were US$ 194 for patients and U$ 189 for the health system in SAT facilities, compared to US$ 336 and US$ 726 in DOT facilities. The ICER was US$ 6,616 per completed DOT treatment compared to SAT.

CONCLUSIONS

Costs incurred by TB patients are high in Rio de Janeiro, especially for those under DOT. The DOT strategy doubles patients' costs and increases by fourfold the health system costs per completed treatment. The additional costs for DOT may be one of the contributing factors to the completion rates below the targeted 85% recommended by WHO.

Has the DOTS strategy improved case finding or treatment success? An empirical assessment

BACKGROUND

Nearly fifteen years after the start of WHO's DOTS strategy, tuberculosis remains a major global health problem. Given the lack of empirical evidence that DOTS reduces tuberculosis burden, considerable debate has arisen about its place in the future of global tuberculosis control efforts. An independent evaluation of DOTS, one of the most widely-implemented and longest-running interventions in global health, is a prerequisite for meaningful improvements to tuberculosis control efforts, including WHO's new Stop TB Strategy. We investigate the impact of the expansion of the DOTS strategy on tuberculosis case finding and treatment success, using only empirical data.

METHODS AND FINDINGS

We study the effect of DOTS using time-series cross-sectional methods. We first estimate the impact of DOTS expansion on case detection, using reported case notification data and controlling for other determinants of change in notifications, including HIV prevalence, GDP, and country-specific effects. We then estimate the effect of DOTS expansion on treatment success. DOTS programme variables had no statistically significant impact on case detection in a wide range of models and specifications. DOTS population coverage had a significant effect on overall treatment success rates, such that countries with full DOTS coverage benefit from at least an 18% increase in treatment success (95% CI: 5-31%).

CONCLUSIONS

The DOTS technical package improved overall treatment success. By contrast, DOTS expansion had no effect on case detection. This finding is less optimistic than previous analyses. Better epidemiological and programme data would facilitate future monitoring and evaluation efforts.

Immunological options for the treatment of tuberculosis: evaluation of novel therapeutic approaches

The emergence of multidrug-resistant tuberculosis strains and the coinfection with HIV, together with advances in immunology, have led to renewed interest regarding ways to exploit the immune responses against Mycobacterium tuberculosis therapeutically. Here we review the fundamentals of tuberculosis therapy in view of the epidemiological and clinical challenges, and explore the experience with immune-based therapies for the treatment of active tuberculosis. These immune-based therapies are discussed here with the aim of assessing their potential use as adjuncts to chemotherapy.

Tuberculosis

Approximately one-third of the world population is infected with Mycobacterium tuberculosis, the organism that causes tuberculosis (TB). After a brief resurgence beginning in the mid-1980s, the incidence of TB is once again declining in the United States. Health care workers, including dentists and their staff, however, remain at risk for occupational acquisition of the disease. This risk can be managed by educating dental health care workers about the oral and systemic manifestations of TB and the mechanisms by which it is spread so that appropriate measures may be taken in the office to minimize the opportunity for disease transmission.

Current thinking on the management of tuberculosis

High-income countries are moving toward tuberculosis (TB) elimination. Sophisticated diagnostic tests and effective treatment regimens are readily available. The range of available resources even makes effective treatment of multidrug-resistant tuberculosis (MDRTB) possible. The introduction of highly active antiretroviral therapy and specific TB control measures has reduced the incidence of HIV-associated TB disease. Unfortunately, the situation in low-income countries that carry 95% of the global TB burden is less positive. TB diagnosis still relies upon sputum smear microscopy. The management of MDRTB remains problematic though guidelines for DOTS-plus programs have been developed, and cheaper second-line drugs are becoming available. The HIV epidemic continues to confound TB control efforts, particularly in sub-Saharan Africa. The appropriate package of interventions for controlling HIV/TB disease remains undefined and unimplemented. The international community must provide the funding and technical support to address the alarming dichotomy in TB control that exists between rich and poor countries.