Interventions to improve adherence to antiretroviral therapy such as peer support and electronic messaging are only partially effective, US investigators report in the online edition of the Journal of Acquired Immune Deficiency Syndromes.
Peer support improved adherence in the short-term, but was not associated with significant changes in either viral load or CD4 cell count, whereas electronic messaging had no effect on reported pill-taking, but did appear to improve laboratory markers.
Antiretroviral treatment can significantly improve the health and life expectancy of HIV-positive people. However, HIV treatment needs to be taken very rigorously and the best results are seen in patients who take all or nearly all of their doses. Many individuals do not achieve such high levels of adherence.
Investigators from Seattle designed a prospective, randomised, controlled trial to see if peer support, electronic messaging, or a combination of the two improved levels of adherence in both the short- and long-term in patients receiving antiretroviral therapy.
Their study ran between 2003 and 2007 and included 224 individuals. These patients were either starting or changing their antiretroviral therapy.
The patients were randomised into one of four arms. The first received peer adherence support. This was provided by other HIV-positive patients at meetings and via telephone calls.
The second group included patients who received text reminders to take their HIV medication, and the third group received both peer support and electronic reminders.
A fourth arm of the study involved patients who received standard adherence support consisting of appointments with healthcare professionals and information about their medication and the importance of adherence.
Adherence support was provided for three months, and at baseline, and then after two weeks, three months, six months and nine months the patients were interviewed about their adherence. Blood samples were taken to measure CD4 cell count and viral load. Adherence was also monitored electronically with pill bottle caps recording each opening.
Just over 50% of individuals in the peer support arms attended at least half of their support meetings and only 40% of electronic adherence reminder messages were acknowledged.
At baseline, 70% of patients reported 100% adherence, but this had declined to 58% after three months, 51% at six months and 49% at nine months.
After three months, 67% of those receiving peer support reported 100% adherence in the past seven days. This compared to 52% of patients not receiving such support and was statistically significant (p = 0.02). However this advantage had disappeared by months six and nine.
Electronic monitoring of adherence suggested a slightly higher level of 100% pill-taking amongst those receiving peer support at month three, but once again this difference disappeared by months six and nine.
There was no evidence that the patients who received electronic messages to remind them to take their HIV medication had better adherence at any time point.
However, those receiving electronic messages were significantly more likely to have a viral load below 1000 copies/ml at all follow-up points than those who did not receive this form of adherence support (p = 0.04).
The investigators suggest that this improved virological outcome was likely to be because there were marginal improvements in adherence which were below the 100% target of the study.
“These findings suggest that receiving informational, emotional, and affirmational support from peers might promote adherence, but that effect did not persist when the support was discontinued. Ongoing social support, perhaps from individuals more integrated into participants’ lives, may hold greater promise in promoting and sustaining long-term adherence”, write the investigators.
They conclude, “maintaining optimal adherence requires a set of complex and dynamic behaviors that may necessitate interventions of equal sophistication with personnel trained and dedicated to providing them on an ongoing basis.”
Simoni JM et al. An RCT of peer support and pager messaging to promote antiretroviral therapy adherence and clinical outcomes among adults initiating or modifying therapy in Seattle, WA, United States. J Acquire Immune Defic Syndr (online edition), 2009.