Various digital health products are being used to support different elements of TB programmes, such as electronic health records, direct data transfer from diagnostic systems and eLearning modules on mobile applications (24). Digital adherence technologies fit into the larger landscape of information technologies and are intended to help improve communication between patients and health-care workers (25). Three technologies have been studied in TB patients and are used to support treatment on a large scale, namely SMS or mobile text, event monitoring devices for medication support (EMMs) and VST for TB (26, 27).
SMS is a standard, built-in function found in all types of mobile telephones worldwide and is generally inexpensive and easy to use. It is thus widely applied for communicating with outpatients. SMS can provide regular, automated message reminders to patients to take their medications, can provide information related to their health or condition (unidirectional) or provide opportunities to interact as well (bidirectional). Most randomized controlled trials of SMS reminders in TB care in different geographical settings failed to show improved patient outcomes when compared with standard care. However, the control groups in these trials achieved high levels of adherence through varying scales of in-person support. The results also suggest that SMS could, to some degree, support adherence at times during treatment when in-person treatment support by a health-care provider is not possible, thus increasing efficiency if not effectiveness. SMS could also be used when there is less necessity to see the patient face to face but there is still a need to keep in contact with the patient in case any concerns arise, such as during the continuation phase of treatment or when a patient has been on stable treatment for a long time without any problems. Research has yet to look more creatively at how SMS can influence adherence behaviour other than just by reminding people to take their pills, such as by channelling cash transfers when treatment milestones are achieved, by combining SMS reminders with other digital solutions and by targeting other points along the patient pathway. The popularity and affordability of SMS present a compelling case for further studies to investigate its potential more exhaustively. Instant messaging via installed mobile software may be used instead of SMS.
EMMs aim to provide more patient flexibility when following up treatment; to support patients with dosing and refill reminders and instructions; and to compile patient-specific dosing histories to enable counselling and differentiated care. EMM boxes consist of automated electronic devices that record and inform the health-care provider about the regularity with which a medicine container is opened. Older devices recorded usage on the container itself, but mobile telephones now allow patient reminders and alerts to be sent to the caregiver when medicine boxes remain unopened for a day or more. A large cluster-randomized trial showed a statistically significant effect of EMM boxes on adherence relative to the standard of care; however, the effect on successful treatment completion was less clear (28). Various technological advances with EMMs, such as requiring patients to dial in (to toll-free numbers) codes revealed when daily blister packs of medications are opened can be used to verify adherence. Under trial, a prototype brand of this technology – 99DOTS (29) – showed similar treatment completion rates when compared to the traditional adherence monitoring and support used by the sites, suggesting that this EMM could be a viable alternative to more labour-intensive forms of medication adherence monitoring (30). Nonetheless, more evaluation is needed of the feasibility and utility of this technology (31).
VST is the form of digital adherence technology that most closely replicates human interaction. The increasing availability of Internet-enabled smartphones and tablet computers equipped with free or customized video communication software has increased options for both real-time (synchronous) and recorded (asynchronous) interactions. Observational studies and trials of VST for TB treatment from different settings suggest that the technique can produce similar outcomes to those produced by in-person monitoring and can improve efficiency (32–35). Given the potential benefits of VST, studies are needed to evaluate it against different standards of care, including self-administered treatment, and to evaluate the acceptability of VST in different population subgroups and in more resource-limited geographical settings.
The advantages of using VST are its potential to provide treatment support from a distance – and even when people travel and cannot visit or be visited by a TB treatment supporter. VST could help achieve better levels of patient interaction at a much lower cost and less inconvenience when compared with in-person treatment support. VST can be used in addition to, or interchangeably with, in-person treatment support or other treatment administration options.
Another option for providing care to patients when face-to-face visits are difficult is to schedule appointments to talk with them by telephone. Questions regarding treatment can be answered, symptoms can be monitored and counselling can be provided. Care should be taken to make sure that patients are able to find a place to talk where they have privacy. Also, if airtime is expensive, the length of time needed for these discussions may be too costly for the patient.
The performance of digital adherence technology under study conditions needs to be translated into programmatic realities. Health-care practitioners and patients require practical aids that can adapt to a patient’s treatment course across a wide variety of different treatment conditions and at distinct time points when treatment interruption is more likely to happen. Technologies for treatment adherence support should be part of an integrated approach that complements the delivery of quality care. For instance, it is unrealistic and undesirable for patients on a longer DR-TB regimen to be placed on exclusive VST for 18–20 months. The risk of interruption is not uniform between patients or even during the treatment of the same patient. Treatment support therefore needs to be flexible throughout a patient’s course of treatment. Special attention is needed when there is a change in the treatment regimen which increases the risk of developing adverse medication reactions when: 1) the patient questions the need to continue the prescribed treatment as symptoms disappear and when she or he feels better; 2) conversely, when the patient may not be feeling better and may feel that treatment s hopeless; 3) when the patient travels far away from the usual treatment centre; or 4) when other events affect a patient’s daily routine and make daily treatment more difficult.
The three digital approaches discussed have specific strengths and weaknesses, which may make them work better in some circumstances rather than in others, as well as differing preferences of the patient and health-care workers. On the basis of the different characteristics of each of the adherence support technologies and the patient’s individual situation, multiple options might be suitable. Two additional issues to consider are access to smartphones and to broadband Internet via mobile subscriptions. Smartphones and tablet computers, given their computing power and storage space, could be a valuable resource for multiple aspects of TB care. These can be useful even when broadband Internet is unavailable or erratic (e.g. recording of asynchronous VST, storage of patient medical records and e-Learning applications). SMS and EMM – which can operate without mobile broadband Internet coverage – are currently the most accessible, affordable and easily expandable treatment support approaches in resource-limited settings. Where mobile Internet is reliable and computer hardware available, solutions with more connectivity requirements can be considered as options.
The increasing range of technologies available for treatment support helps improve person-centred care. Nonetheless, digital technologies are still to be regarded as tools and should not replace face-to-face interactions when these are more appropriate. Another important consideration is that digital adherence technologies depend on the regular observation of a person’s behaviour in order to follow up adherence. This poses a number of ethical issues (7). Some technologies may affect a patient’s privacy more than others – such as receiving a daily SMS text message that asks for a reply, the automated monitoring of the opening of a medicine box, or a video recording of a medicine being swallowed. The benefits of having recordings of patients taking their medications and the ability to text or speak with patients have to be balanced against potential downsides – such as patients feeling they are being controlled, a sense of being tracked and distrusted, loss of empowerment and concerns about confidentiality. These issues need to be discussed at length with the patients (see Section 4.1. on Guiding principles for health education and counselling). Further issues to consider when determining which treatment support technology may be best for a patient include the ability and willingness to learn to use the technology. Visual impairment and literacy may make it difficult for patients to use mobile telephones correctly. Another concern is that the cost of airtime or data may be too expensive for patients to use some of these technologies. Acceptability and preferences should be explored with each patient as part of her or his adherence plan.