Electronic monitoring of antiretroviral adherence in "real time" boosts pill taking and need for intensive adherence support

Electronic monitoring of antiretroviral adherence in “real time” significantly increases the proportion of treatment doses taken on time and reduces the frequency of treatment interruptions, according to a Ugandan study published in AIDS.

The study had an observational design. Patients switched from electronic adherence monitoring (EAM) – which stores information about the date and time pill containers are opened for later download to a computer – to real-time EAM, with data about opening of containers transmitted instantly via wireless networks. Average adherence levels increased from 84% with standard EAM to 94% after switching to real-time EAM. This increase was sustained during the six months following the switch. With both types of EAM, patients received support in the event of prolonged treatment interruptions.

“Compared to standard EAM, real-time EAM plus home visits for sustained interruptions was associated with increased average adherence and fewer adherence interruptions – both of which are associated with viral suppression and reduced immune activation,” comment the authors. But switching to real-time EAM did not increase rates of viral suppression.

Adherence to pill-taking schedules is key to the success of antiretroviral therapy. EAM is widely used to monitor adherence. However, as data gathered using EAM is only downloaded at clinic visits, ongoing intermittent adherence and/or sustained treatment interruptions can only be detected retrospectively, meaning that viral rebound may already have occurred by the time adherence problems are identified. The development of real-time EAM means that missed doses and interruptions can be detected immediately. This means that electronic reminders can be instantly sent to patients, and when necessary, more intensive adherence support can be promptly offered.

Investigators in Uganda wanted to see if switching from standard to real-time EAM was associated with increased adherence to HIV therapy; if any increases were sustained over six months; and if real-time EAM reduced the frequency of home visits to investigate sustained treatment interruptions (48 hours or more).

A total of 112 people were recruited to the study. Median age was 36 years, 68% were female and 82% were literate. Median CD4 count before the initiation of HIV therapy was 141 cells/mm³.

Adherence was monitored for six months using standard EAM. During this period, patients took an average of 84% of their doses. After the switch to real-time EAM, average adherence increased significantly to 93% (p < 0.001). This increase was sustained over the next six months. The mean number of treatment interruptions lasting 48 hours or more decreased from 2.2 in the standard EAM period to 0.7 after the change to real-time EAM.

There were no significant socio-demographic or behavioural changes between the standard EAM and real-time EAM periods.

However, switching to real-time EAM did not increase rates of viral suppression. “Overall high adherence reduced the ability to show a difference in viral suppression between the monitoring periods,” explain the authors.

An additional 255 people had only real-time EAM. Their adherence level was almost identical to that observed in the people who switched from standard EAM (92% vs 93%). However, the mean number of per-patient 48 hour (or longer) treatment interruptions was higher for individuals starting therapy with real-time EAM than those who switched (1.9 vs 0.7; p < 0.001).

“Adherence with real-time EAM plus follow-up was high regardless or prior experience with standard EAM, suggesting that a real-time approach may effectively promote adherence during early and chronic treatment,” comment the authors. “Our findings strengthen growing evidence that real-time EAM with follow-up triggered by incomplete adherence is an effective intervention.”