Symptom management for individuals living with HIV/AIDS continues to be an important biomedical goal. However, the results of this study suggest that a peer-based symptom management intervention may not decrease total symptom intensity or improve medication adherence and quality of life in women living with HIV/AIDS, when compared to a control group who received a symptom management guide-book.
The differences between the two groups on symptom intensity was often less than 0.20 mean points at any point in time which yielded a very small effect size. Previous research with this intervention yielded an effect size of 0.61 (Gifford et al., 1998
). However, they were working with a sample that was more recently diagnosed with HIV and compared the intervention group to usual care. The present sample had been living with HIV for many years and reported few symptoms at the beginning of this study (mean symptom intensity of 0.49 on the SSC-HIVrev). Consequently, this may have led to a natural floor effect among those participating in the intervention because they were unable to report lower symptom intensity given the boundaries of the scale. Additionally, a more recent trial testing the effect of the symptom management manual, used as the control condition in the present study, yield ed a 0.4 effect size (Hedges & Olkin, 1985
; Wantland et al., 2008
). This larger effect size for the control condition may explain the diminished effect size in symptom intensity between the intervention and control groups over time. Several other explanations exist to explain the discrepancies in effect sizes between the original and present study of the PSMP.
The original study was tested in an all-male, relatively well-educated, mainly white sample. Additionally, the original study was completed in 1996. Consequently, the intervention was tested in a very different sample in a time when HIV/AIDS self and symptom management were very different (Chou et al., 2004
; Portillo et al., 2007
). While the intervention has been updated in the past decade, it was updated based on new medical interventions and not to specifically reflect the needs of women living with HIV/AIDS. For example, qualitative findings suggested that the intervention content could be modified to include topics on gynecological symptoms and menopause, childbearing/rearing, stigma, and sexual negotiation (HRSA, 2005
In recognition of these growing needs of minority women living with AIDS, investigators developed and tested the SMART/EST Women’s Project (Ironson et al., 2005
; Jones et al., 2007
). In contrast to the present study, professional therapists, not peers, led this intervention. This two-phase intervention was a 22-week group therapy intervention focusing on cognitive-behavioral stress management related to HIV/AIDS. The analysis of the SMART/EST intervention on HAART medication adherence indicated that participants with exposure to the group sessions had increased medication adherence compared to participants who received the educational control. The intervention also predicted an increase in coping skills related to medication adherence (Jones et al., 2007
). The investigators attributed these results to an increase in social learning and emotional support which is supported by other recent literature (Brown & Vanable, 2008
). However, other studies have found the positive effect of cognitive-behavioral interventions on HAART medication adherence and stress management is short-lived (Brown & Vanable, 2008
; Johnson, Charlebois, Morin, Remien, & Chesney, 2007
Qualifications of peer leaders are also a potential source of effect size discrepancies. In this study, the peer leaders were representative of the overall sample. They had a high-school diploma or General Educational Development Test (GED), identified as African-American or Latina, were single and had a history of substance abuse. While it is desirable to have peer leaders identify with the participants on these variables, the low education level was an impediment to delivering the scripted intervention as intended. For example, the peers had a hard time reading parts of the script and would often get flustered during the intervention sessions. Several of the qualitative comments supported this barrier.
Finally, one potential reason for the small effect size is that the dose was not sufficient for this population. While the intervention was ongoing, there was a small, although not significant trend toward a decrease in symptom intensity missed HIV medications in the intervention group. However, this trend disappeared when the intervention sessions concluded. These findings are compatible with recent clinical trials evaluating the effect of behavioral interventions on medication adherence (Johnson et al., 2007
; Parsons, Golub, Rosof, & Holder, 2007
; Sampaio-Sa et al., 2008
) and is consistent with a recent review suggesting that effective medication adherence interventions tend to last longer than 12 weeks (Sergio et al., 2006
). Of note, the SMART/EST trial did find a significant difference in HAART medication adherence between the intervention and control conditions. However, the dose of their intervention was much longer, both phases lasted 22 weeks, and the measurements were taken immediately after the intervention was complete (Jones et al., 2007
The primary limitation of this study is its small sample size, which limited the ability to detect significant changes between the two groups over time. While the sample size was based on the original pilot study, the aforementioned factors may have led to a much smaller effect size. Additionally, the sample size was based on the primary outcome, change in symptom intensity, which may have limited the ability to detect changes in medication adherence and quality of life. Women also self-selected into this study, which may have biased the results.
Despite the non-significant findings and limitations in this study, previous research does suggest that peer-based interventions may work to help increase symptom management and self-care (Doull et al., 2004
). Future work on similar interventions in comparable populations should consider whether the content of the intervention addresses the more general needs of people living with multiple chronic diseases and in poverty. Future work should also consider using a combination of peers and professionals to help efficiently deliver the content when other barriers exist (i.e., limited literacy). It is also advisable to consider a larger intervention dose and longer follow-up period in order to test the long-term efficacy of future interventions.