Family support just as good as directly observed therapy for TB treatment, Nepal study finds

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DOTS and its detractors

Since the 1950s, directly observed therapy has been a tool used to ensure that a person with tuberculosis takes all of the medication needed to cure their infection and stave off drug resistance. Treatment worked and TB became truly rare in the Western Hemisphere. However, after the HIV epidemic struck New York and other American cities in the late 1980s and early 1990s, there was a resurgence of TB, particularly in the homeless, IDU and the prison populations. Directly observed therapy of these sometimes difficult-to-treat groups was largely credited with successfully containing TB in those settings.

But HIV was having a much greater impact on TB control in other parts of the world, so in 1997, the WHO and the International Union against Tuberculosis and Lung Disease (the Union) instituted a new strategy branded around directly observed therapy. The ‘DOTS’ strategy consisted of five key elements:

  • Political commitment to provide adequate resources to fight TB
  • Detection of active infectious TB by sputum smear microscopy
  • A system to ensure regular drug supplies
  • A standard recording and reporting system that assesses treatment outcomes
  • A standard short-course of at least four drugs including rifampicin, administered by directly observed therapy

Despite the perceptions that DOTS helped contain TB in New York, the last point has been contentious. In fact, Garner and Volmink, who conducted a soon to be published Cochrane Review of DOTS, note, "at the time WHO’s Director General announced the policy in 1997, no trial testing direct observation in tuberculosis existed. In 2006, there are ten trials and 3985 participants in the Cochrane review, with no difference in treatment success shown between policies of direct observation compared with self-administration."

Nevertheless, many countries rolled ahead with universal DOTS, trying to marshal troops of health care workers to monitor adherence in patients, who sometimes lived far from clinics. While the approach seems to have contained TB in most of the world with more developed health care systems, the one-size fits all approach has been an abject failure in Africa, where the TB epidemic continues to spiral out of control. "This standard blueprint approach is reminiscent of machine theory in expectations of how people and systems will behave," wrote Garner and Volmink.

Glossary

directly observed therapy (DOT)

When a health care professional watches as a person takes each dose of a medication, to verify that all doses are taken as prescribed.

p-value

The result of a statistical test which tells us whether the results of a study are likely to be due to chance and would not be confirmed if the study was repeated. All p-values are between 0 and 1; the most reliable studies have p-values very close to 0. A p-value of 0.001 means that there is a 1 in 1000 probability that the results are due to chance and do not reflect a real difference. A p-value of 0.05 means there is a 1 in 20 probability that the results are due to chance. When a p-value is 0.05 or below, the result is considered to be ‘statistically significant’. Confidence intervals give similar information to p-values but are easier to interpret. 

smear

A specimen of tissue or other material taken from part of the body and smeared onto a microscope slide for examination. A Pap smear is a specimen of material scraped from the cervix (neck of the uterus) examined for precancerous changes.

odds ratio (OR)

Comparing one group with another, expresses differences in the odds of something happening. An odds ratio above 1 means something is more likely to happen in the group of interest; an odds ratio below 1 means it is less likely to happen. Similar to ‘relative risk’. 

intent to treat analysis

All participants in a clinical trial are included in the final analysis, in the groups they were originally assigned to, whether or not they actually completed their course of treatment. This method provides a better estimate of the real-world effect of a treatment than an ‘on treatment’ analysis.

Recognising that there aren’t enough trained health care workers to go around in every setting, WHO has suggested using community volunteers for DOTS — and this has indeed worked in some settings. Even so, the authors (Newell et al) of the Nepal study noted two concerns: "Direct observation of treatment could reduce treatment seeking and completion because of the cost, inconvenience, and stigma associated with visiting a health centre or community volunteer daily; and emphasis is placed on identifying when patients have defaulted from treatment rather than supporting them to complete treatment."

Treatment activists also have problems with DOTS because it isn’t patient-centred. At the opening ceremony of the 36th World Conference on Lung Health last year, Zachie Achmat of South Africa’s Treatment Action Campaign said that with DOTS "patients are not regarded as independent autonomous people with dignity and the ability to take control of their own health or illness. People with TB are treated as public health cases."

One possible alternative approach is to identify and train a family member to assist a person with TB complete their treatment — and the family would have an incentive to make sure that TB is cured. But the Union and WHO have generally frowned on this approach because studies have not evaluated it under TB control programme conditions. But similar to using community health volunteers for DOTS, family based support could be particularly useful when people live in far flung areas with little access to health services.

Family members can help a person with tuberculosis successfully complete treatment just as well as directly observed therapy (DOTS) offered by community health volunteers, according to a study conducted in the remote hill and mountain districts of Nepal. Both approaches met international targets for treatment success according to the report, which was published in the March 18th issue of The Lancet — though neither approach identified new TB cases as well as when a trained health worker is involved in treatment.

In an editorial accompanying the piece, Drs Paul Garner and Jimmy Volmink, of the Liverpool School of Tropical Medicine and Stellenbosch University in South Africa, wrote that the study gives "credence to treatment managed within the family rather than directly imposed by health workers."

Nepal

One such setting is Nepal, where 20,000 people develop active smear-positive (i.e., infectious) TB and 6000–8000 die of TB each year. About a third of the people with TB live in the hill and mountain districts of Nepal. “Many patients have to walk for a day or more to the nearest DOTS centre,” wrote Newell et al.

Charged with the task of finding a more feasible way to reach such people, Newell et al decided to look at two approaches: using a female community health volunteer or a village health worker to supervise treatment on a daily basis, or using 'family-member DOTS' which was defined "as a strategy with drug taking supervised daily by a household member selected by the patient, with drugs provided to the patient’s supervisor every week."

Conclusion and discussion

"Both strategies are acceptable for use in the hill districts of Nepal," concluded Newell et al. "They might also be appropriate in many other parts of the world where—because of difficult terrain, low population density, or conflict—direct observation of treatment by health workers is not feasible."

The authors stress that this patient-responsive approach is more ethical than expecting people to go to the clinic: "We believe that it is unethical to implement DOTS strategies that cause very high direct or opportunity costs to patients: we would expect such strategies to show high non-completion rates or, if alternative modes of treatment were available, low case-finding rates."

In addition, the family-member DOTS strategy does not have to rely on volunteers, who Newell et al wrote "are becoming increasingly overloaded in Nepal because of the many different health programmes requesting their help."

Although defined as family-member 'DOTS,' Garner and Volmink noted, "We do not know the dynamics in the family or the relationship of the monitor to the patient. But what is interesting is that the tuberculosis officer is engaging in a social process within the family: there is negotiation and there is sharing of responsibility. Whether the appointee actually directly observes is probably immaterial."

They concluded that the researchers in Nepal "have been able to loosen the definition around direct observation still further to allow a more thinking approach for health staff that is contingent on patients’ needs and circumstances."

It is interesting to note that WHO and Stop TB’s New Global Plan to Stop TB frequently calls for more patient-friendly and empowering approaches, yet not once does it mention family-based adherence support as a possible programmatic option.

The trial and its results

To assess how effective these two strategies were (in terms of success rates and case-finding rates), Newell et al conducted a randomised controlled trial between mid-July 2002, and mid-July 2003. Ten health districts, rather than individual patients, were used as the unit of randomisation. Five districts (549 patients) were allocated to community DOTS and five (358 patients) were allocated to family-member DOTS.

WHO has set a target of 85% as a routine measure of DOTS success, which both arms of the study achieved. In an intent-to-treat analysis, community DOTS and family-member DOTS achieved success rates of 85% and 89%, respectively (odds ratio of success for community DOTS relative to family-member DOTS, 0.67 [95% CI 0.41–1.10]; p=0.09). While the difference between the two arms was not significant, the family-based arm was significantly better than the WHO target (difference 4.1% [95% CI 0.9-7.3]).

There was no significant difference between the two arms in treatment non-completion or death. In both groups 4% did not complete treatment; while 9% in the community DOTS group vs. 5% in the family-member group died (odds ratio 1.7[95% CI 0.8 to 3.2] p=0.08).

However, detection of new TB cases fell significantly short of WHO’s target of 70%, with 63% detected with the community strategy and 44% with family-member DOTS. Of note, case detection was significant more common in men than women in both groups.

References

Newell, JN et al. Family-member DOTS and community DOTS for tuberculosis control in Nepal: cluster-randomised controlled trial. Lancet; 367: 903–909, 2006.

Garner P, Volmink J. Families help cure tuberculosis. Lancet; 367: 878-879, 2006.