Despite the availability of effective drugs to treat tuberculosis (TB), two million people die from the disease each year. To be cured, drugs must be taken for at least six months, and many people find it difficult to complete treatment. Incomplete treatment can lead to prolonged infectiousness, drug resistance, relapse of TB, or even death.

A variety of measures have been developed to improve patient’s adherence to TB treatment. Directly observed therapy (DOT) is one approach, where an appointed individual (health worker, family or community member) directly observes patients taking their drugs. The World Health Organization (WHO) and others widely recommend this approach for the control of TB. The advantages of this approach are that people can be closely monitored. However, there may be substantial resource implications, and it may make adherence worse if people have to travel long distances to have their treatment supervised. 

The authors contrast this to directly observed treatment strategies, which are a package of interventions, with direct observation being just one. Thus WHO's DOTS strategy has come to mean more than direct observation. Observational studies have shown benefits of these programmes, but this benefit may be due to other aspects of the programme and not to the direct observation specifically. When other conditions are the same, how does directly observed therapy compare with self-administration of treatment?

Researchers from the South African Cochrane Centre and Liverpool School of Tropical Medicine, UK, conducted a Cochrane systematic review to answer this question. They identified ten trials, seven from low and middle-income countries and three from high-income countries, with two of the latter evaluating services specifically for intravenous drug users. Authors reported no difference between direct observation and self-administration groups in the percentage of patients who were successfully treated, in either the general public or intravenous drug users.

The reviewers concluded that:

• Research has not demonstrated that policies of direct observation of TB treatment are any better than policies of self treatment at home for achieving treatment success.
• Studies comparing this approach to other strategies aimed at improving adherence to treatment would be useful.

Source(s):
'Systematic review: Directly observed therapy for treating tuberculosis', Cochrane Database of Systematic Reviews Issue 3, by Jimmy Volmink and Paul Garner, 2006

id21 Research Highlight: 29 September 2006

Further Information:
Jimmy Volmink
Faculty of Health Sciences
University of Stellenbosch
PO Box 19063
Tygerberg 7505
South Africa

Tel: +27 21 938 9643
Fax: +27 21 938 9558
Contact the contributor: jvolmink@sun.ac.za

Cochrane Infectious Diseases Group, DFID Effective Health Care Research Programme Consortium

Other related links:
'Family members observe TB treatment in rural Nepal'

'Factors influencing adherence to direct observation of TB treatment in Pakistan'

'Keep it in the family: supporting TB treatment in Swaziland'

'Is watching tablet taking helpful? TB DOTS and costs in Pakistan'

'DOT topic – expanding the debate on directly observed tuberculosis treatment'

'Keeping an eye on costs – community health workers monitor TB treatment'

'Volunteer supervisors in TB treatment programmes - what's in it for them?'