Tuberculosis (TB) requires at least six months of treatment. If treatment is incomplete, patients may not be cured and drug resistance may develop. Directly Observed Therapy (DOT) is a specific strategy, endorsed by the World Health Organization, to improve adherence by requiring health workers, community volunteers or family members to observe and record patients taking each dose.
To evaluate DOT compared to self-administered therapy in people on treatment for active TB or on prophylaxis to prevent active disease. We also compared the effects of different forms of DOT.
We searched the following databases up to 13 January 2015: the Cochrane Infectious Diseases Group Specialized Register; the Cochrane Central Register of Controlled Trials (CENTRAL), published in the Cochrane Library; MEDLINE; EMBASE; LILACS and mRCT. We also checked article reference lists and contacted relevant researchers and organizations.
Randomized controlled trials (RCTs) and quasi-RCTs comparing DOT with routine self-administration of treatment or prophylaxis at home.
Data collection and analysis
Two review authors independently assessed risk of bias of each included trial and extracted data. We compared interventions using risk ratios (RR) with 95% confidence intervals (CI). We used a random-effects model if meta-analysis was appropriate but heterogeneity present (I2 statistic = 50%). We assessed the quality of the evidence using the GRADE approach.
Eleven trials including 5662 participants met the inclusion criteria. DOT was performed by a range of people (nurses, community health workers, family members or former TB patients) in a variety of settings (clinic, the patient's home or the home of a community volunteer).
DOT versus self-administered
Six trials from South Africa, Thailand, Taiwan, Pakistan and Australia compared DOT with self-administered therapy for treatment. Trials included DOT at home by family members, community health workers (who were usually supervised); DOT at home by health staff; and DOT at health facilities. TB cure was low with self-administration across all studies (range 41% to 67%), and direct observation did not substantially improve this (RR 1.08, 95% CI 0.91 to 1.27; five trials, 1645 participants, moderate quality evidence). In a subgroup analysis stratified by the frequency of contact between health services in the self-treatment arm, daily DOT may improve TB cure when compared to self-administered treatment where patients in the self-administered group only visited the clinic every month (RR 1.15, 95% CI 1.06 to 1.25; two trials, 900 participants); but with contact in the control becoming more frequent, this small effect was not apparent (every two weeks: RR 0.96, 95% CI 0.83 to 1.12; one trial, 497 participants; every week: RR 0.90, 95% CI 0.68 to 1.21; two trials, 248 participants).
Treatment completion showed a similar pattern, ranging from 59% to 78% in the self-treatment groups, and direct observation did not improve this (RR 1.07, 95% CI 0.96 to 1.19; six trials, 1839 participants, moderate quality evidence).
DOT at home versus DOT at health facility
In four trials that compared DOT at home by family members, or community health workers, with DOT by health workers at a health facility there was little or no difference in cure or treatment completion (cure: RR 1.02, 95% CI 0.88 to 1.18, four trials, 1556 participants, moderate quality evidence; treatment completion: RR 1.04, 95% CI 0.91 to 1.17, three trials, 1029 participants, moderate quality evidence).
DOT by family member versus DOT by community health worker
Two trials compared DOT at home by family members with DOT at home by community health workers. There was also little or no difference in cure or treatment completion (cure: RR 1.02, 95% CI 0.86 to 1.21; two trials, 1493 participants, moderate quality evidence; completion: RR 1.05, 95% CI 0.90 to 1.22; two trials, 1493 participants, low quality evidence).
Specific patient categories
A trial of 300 intravenous drug users in the USA evaluated direct observation with no observation in TB prophylaxis to prevent active disease and showed little difference in treatment completion (RR 1.00, 95% CI 0.88 to 1.13; one trial, 300 participants, low quality evidence).
From the existing trials, DOT did not provide a solution to poor adherence in TB treatment. Given the large resource and cost implications of DOT, policy makers might want to reconsider strategies that depend on direct observation. Other options might take into account financial and logistical barriers to care; approaches that motivate patients and staff; and defaulter follow-up.
PLAIN LANGUAGE SUMMARY
Directly observing people with TB take their drugs to help them complete their treatment
This Cochrane Review summarises trials evaluating the effects of directly observed therapy (DOT) for treating people with tuberculosis (TB) or people on prophylaxis to prevent active disease compared to self-administered treatment. After searching for relevant trials up to 13 January 2015, we included 11 randomized controlled trials, enrolling 5662 people with TB, and conducted between 1995 and 2008.
What is DOT and how might it improve treatment outcomes for people with TB
DOT is one strategy to ensure that patients with TB take all their medication. An 'observer' acceptable to the patient and the health system observes the patient taking every dose of their medication, and records this for the health system to monitor.
The World Health Organization currently recommends that people with TB are treated for at least six months to achieve cure. These long durations of treatment can be difficult for patients to complete, especially once they are well and need to return to work. Failure to complete treatment can lead to relapse and even death in individuals, and also has important public health consequences, such as increased TB transmission and the development of drug resistance.
What the research says
Overall, cure and treatment completion in both self-treatment and DOT groups was low, and DOT did not substantially improve this. Small effects were seen in a subgroup of studies where the self-treatment group were monitored less frequently than the DOT group.
There is probably no difference in TB cure or treatment completion when the direct observation was conducted at home or at the clinic (moderate quality evidence). There is probably little or no difference in TB cure direct observation is conducted by a community health worker or family member (moderate quality evidence) and there may be little or no difference in treatment completion either (low quality evidence).
Direct observation may have little or no effect on treatment completion in injection drug users (low quality evidence).
The authors conclude that DOT on its own may not offer the solution to poor adherence in people taking TB medication.