Systematic Review, Meta-analysis, and Cost-effectiveness of Treatment of Latent Tuberculosis to Reduce Progression to Multidrug-Resistant Tuberculosis.

BACKGROUND.: Evidence-based recommendations for treating persons having presumed latent tuberculosis (LTBI) after contact to infectious multidrug-resistant (MDR) tuberculosis (TB) are lacking because published data consist of small observational studies. Tuberculosis incidence in persons treated for latent MDR -TB infection is unknown. METHODS.: We conducted a systematic review of studies published 1 January 1994-31 December 2014 to analyze TB incidence, treatment completion and discontinuation, and cost-effectiveness. We considered contacts with LTBI effectively treated if they were on ≥1 medication to which their MDR-TB strain was likely susceptible. We selected studies that compared treatment vs nontreatment outcomes and performed a meta-analysis to estimate the relative risk of TB incidence and its 95% confidence interval. RESULTS.: We abstracted data from 21 articles that met inclusion criteria. Six articles presented outcomes for contacts who were treated compared with those not treated for MDR-LTBI; 10 presented outcomes only for treated contacts, and 5 presented outcomes only for untreated contacts. The estimated MDR-TB incidence reduction was 90% (9%-99%) using data from 5 comparison studies. We also found high treatment discontinuation rates due to adverse effects in persons taking pyrazinamide-containing regimens. Cost-effectiveness was greatest using a fluoroquinolone/ethambutol combination regimen. CONCLUSIONS.: Few studies met inclusion criteria, therefore results should be cautiously interpreted. We found a reduced risk of TB incidence with treatment for MDR-LTBI, suggesting effectiveness in prevention of progression to MDR-TB, and confirmed cost-effectiveness. However, we found that pyrazinamide-containing MDR-LTBI regimens often resulted in treatment discontinuation due to adverse effects.

Prevalence of extended treatment in pulmonary tuberculosis patients receiving first-line therapy and its association with recurrent tuberculosis in Beijing, China.

BACKGROUND: In China, it is known that extended treatment is given to patients with pulmonary TB after they have successfully completed 6 months of first-line treatment. This practice is not officially reported to the National Tuberculosis Control Programme, so there are no data on its prevalence, its possible benefits in terms of preventing recurrent disease or the costs. This study aimed to provide information, from a single TB dispensary in Beijing, China, on the prevalence of extended anti-TB treatment and its relationship with recurrent TB. METHODS: Retrospective cohort study using the electronic national TB information system and dispensary medical records. RESULTS: Of 935 patients with pulmonary TB who completed 6-7 months of first-line drug treatment, 399 (43%) were given extended treatment. This was more common in patients with smear-positive disease, and those with lung cavities and more extensive radiographic lobar involvement at the time of diagnosis. Over 3-4 years' follow-up, recurrent disease was not significantly different in patients who received extended treatment (2.8%, 11/399) as compared to those who received the standard 6-month treatment (3.7%, 20/534). The median length of extended treatment was 89 days at a median cost of US$111 for drugs and US$32 for laboratory examinations. CONCLUSIONS: This study shows that extended treatment is common in one TB dispensary in Beijing. Further studies are needed to determine the countrywide prevalence of this practice and ascertain more conclusively the apparent lack of benefit.

Impact of DOTS expansion on tuberculosis related outcomes and costs in Haiti.

BACKGROUND: Implementation of the World Health Organization's DOTS strategy (Directly Observed Treatment Short-course therapy) can result in significant reduction in tuberculosis incidence. We estimated potential costs and benefits of DOTS expansion in Haiti from the government, and societal perspectives. METHODS: Using decision analysis incorporating multiple Markov processes (Markov modelling), we compared expected tuberculosis morbidity, mortality and costs in Haiti with DOTS expansion to reach all of the country, and achieve WHO benchmarks, or if the current situation did not change. Probabilities of tuberculosis related outcomes were derived from the published literature. Government health expenditures, patient and family costs were measured in direct surveys in Haiti and expressed in 2003 US$. RESULTS: Starting in 2003, DOTS expansion in Haiti is anticipated to cost $4.2 million and result in 63,080 fewer tuberculosis cases, 53,120 fewer tuberculosis deaths, and net societal savings of $131 million, over 20 years. Current government spending for tuberculosis is high, relative to the per capita income, and would be only slightly lower with DOTS. Societal savings would begin within 4 years, and would be substantial in all scenarios considered, including higher HIV seroprevalence or drug resistance, unchanged incidence following DOTS expansion, or doubling of initial and ongoing costs for DOTS expansion. CONCLUSION: A modest investment for DOTS expansion in Haiti would provide considerable humanitarian benefit by reducing tuberculosis-related morbidity, mortality and costs for patients and their families. These benefits, together with projected minimal Haitian government savings, argue strongly for donor support for DOTS expansion.

Tuberculosis prevention in Mexican immigrants: limitations of short-course therapy.

BACKGROUND: Two months of rifampin and pyrazinamide (RIF/PZA) for tuberculosis prevention has been advocated as a way to improve adherence in mobile populations, such as recent immigrants. However, RIF/PZA requires intensive patient and laboratory monitoring for hepatotoxicity. OBJECTIVES: To describe the feasibility and outcomes of using RIF/PZA for TB prevention during a tuberculosis outbreak in a Mexican immigrant community, where 23 adults and 11 children were treated with RIF/PZA between August 2001 and October 2001. METHODS: Retrospective chart review and interviews with health department employees were conducted to assess completion rates, hepatotoxicity, cost, and feasibility of monitoring. RESULTS: Ten (91%) children and 13 (57%) adults completed RIF/PZA. One child (9%) and four adults (17%) developed drug-induced hepatitis. Cultural barriers affected care. The adults resisted the biweekly blood draw, believing it would "drain them of energy." RIF/PZA, plus monitoring, was twice as costly as 4 months of rifampin. CONCLUSIONS: RIF/PZA was associated with significant hepatotoxicity, poor completion, and cultural barriers to monitoring, and was more costly than standard therapy. Tuberculosis prevention must address potential clinical, cultural, and economic barriers to completion and monitoring of short-course therapy in immigrants.

Short-course rifampin and pyrazinamide compared with isoniazid for latent tuberculosis infection: a cost-effectiveness analysis based on a multicenter clinical trial.

Two months of treatment with rifampin-pyrazinamide (RZ) and 9 months of treatment with isoniazid are both recommended for treatment of latent tuberculosis infection in adults without human immunodeficiency virus infection, but the relative cost-effectiveness of these 2 treatments is unknown. We used a Markov model to conduct a cost-effectiveness analysis to assess the impact on life expectancy and costs based on the results of a recent clinical trial that compared the rates of adverse events and completion of the 2 treatment regimens. Compared with no treatment, both regimens increased life expectancy by 1.2 years, but RZ cost 273 dollars more per patient. Sensitivity analyses showed that, assuming equal efficacy between the 2 regimens, there was no threshold completion rate for RZ at which the 2 treatments would be of equal net cost. Under most circumstances, treatment of latent tuberculosis infection with isoniazid is cost-saving than treatment with RZ.