By Barbara Greenwood Dufour
In much of Canada, the risk of contracting tuberculosis (TB) in Canada is very low. However, the disease is still a significant concern among socioeconomically disadvantaged populations, immigrants, and Indigenous Peoples living in Canada. TB is an infectious disease that primarily affects the lungs but also the bones, joints, lymph nodes, or central nervous system. It’s very contagious, being spread through the air whenever an infected person coughs or sneezes.
Effective treatment is, fortunately, available. Because treatment can require multiple medications over the course of several months, it’s recommended to have a health care provider watch patients take each dose to help ensure they’re adhering to treatment until they are cured. This is called directly observed therapy or DOT. Sticking with TB treatment until the end is important because incomplete treatment can lead to a drug-resistant form of TB that requires longer and more toxic treatment regimens. And people who aren’t effectively treated continue to be at risk of transmitting the disease to others.
Completing the entire course of treatment, though, can be challenging for some people for a variety of reasons. For example, those living in remote northern communities, such as Nunavut, face challenges in accessing health care facilities due to severe winter weather and a lack of roads in addition to the shortage of health care staff to provide DOT. This coupled with the fact that in Inuit communities, according to the Public Health Agency of Canada, the rate of TB is almost 300 times higher than that of Canadian-born non-Indigenous populations makes the disease more difficult to eradicate.
Harnessing mobile technology to perform DOT from a distance — which is sometimes called video DOT or VDOT — may overcome the travel and access barriers and reduce the inconvenience and cost of traditional DOT. CADTH recently included a summary of VDOT in its Health Technology Update newsletter. CADTH’s Horizon Scanning Service continually scans the horizon for emerging drugs, medical devices, and procedures that could have a significant impact on patient care and the health care system but are not yet widely available, in routine clinical use, or licensed for use in Canada.
VDOT allows patients to use a tablet, computer with a webcam, or smartphone so that their health care providers can see them taking their medications. It can be performed either synchronously — where patients transmit live video and health care providers see it in real time — or asynchronously — where patients record, save, and send videos to their health care providers. Common videoconferencing programs, such as Skype and FaceTime, can be used, although there have also been some specialized platforms developed.
Does VDOT increase TB treatment adherence? It’s unclear. In researching this topic for Health Technology Update, the CADTH Horizon Scanning Service looked for any available evidence on VDOT for managing TB, finding information on four observational studies and one randomized controlled trial. The conclusions of these studies are mixed — three (including the randomized controlled trial) reported that VDOT resulted in higher adherence (although only slightly in one study), and two found that the adherence rate with VDOT was similar to that of traditional DOT. It should be noted that CADTH only identified and did not critically appraise any of these studies, and so it has not assessed their quality. But a quick look at the conclusions of these studies gives us a sense that more evidence is needed. Since the CADTH Health Technology Update article was published, the results of a UK randomized controlled trial were published in The Lancet, which found that VDOT was more effective than DOT, less costly, and preferable for patients.
For remote communities, VDOT might have the potential to address the significant geographic barriers to receiving TB treatment. Because VDOT requires high-bandwidth Internet access or smartphones with a data plan, it can’t be offered in many remote Canadian communities at the moment (note that about half of the communities in Nunavut currently don’t have cell phone service). But, a new satellite infrastructure expected to be put in place this year that could make the implementation of VDOT possible for these populations in the near future.
Barbara Greenwood Dufour is a Knowledge Mobilization Officer at CADTH.