A review of previous studies suggests that favorable levels of antiretroviral therapy adherence can be reached among HIV-infected patients in sub-Saharan Africa, while adherence remains a concern in North America.
Antiretroviral therapy (ART) has improved the health of many human immunodeficiency virus (HIV) positive individuals who otherwise would have died. However, treatment effectiveness relies on sustained adherence, which is a serious challenge to those receiving ART, according to background information in the article. The regimens are often complicated, can include varying dosing schedules, dietary restrictions, and adverse effects. Consistently high levels of adherence are necessary for reliable viral suppression and prevention of resistance, disease progression, and death. There has been concern that African patients, many of whom live in poverty and lack formal education, will have suboptimal adherence to ART.
Edward Mills, Ph.D., M.Sc., of the Centre for International Health and Human Rights Studies, Toronto, Ontario, Canada, and colleagues conducted a review of available ART adherence data in both Africa and a resource-rich setting, North America, to determine the level of adherence in emerging African treatment programs relative to the more established North American programs. Eleven electronic databases were searched along with major conference abstract databases (inclusion dates: inception of database up until April 18, 2006) for all English-language articles and abstracts; and researchers and treatment advocacy groups were contacted.
Thirty-one studies from North America and 27 studies from sub-Saharan Africa were included. African studies represented 12 sub-Saharan countries. Of the North American studies, 71 percent used patient self-report to assess adherence; this was true of 66 percent of African assessments. The researchers found that North American studies (17,573 patients total) yielded a pooled estimate of 55 percent of the populations achieving adequate levels of adherence and African studies (12,116 patients total) yielded a pooled estimate of 77 percent, indicating a higher level of ART adherence in Africa.
"The findings from this systematic review and meta-analysis suggest that ART adherence among sub-Saharan African patients in early treatment programs are favorable, although it should be noted that the complexity of treatment regimens is potentially greater in North America, which should be considered when interpreting the data," the authors write.
The researchers add that the barriers to adherence among impoverished individuals in North America appear to be due to poor patient-clinician relationships, untreated depression, substance abuse, and other factors that are common among poor individuals in the North America setting rather than poverty itself.
"We have shown that there are patients in both settings that have suboptimal adherence and that factors beyond poverty play an important role. Clinicians should therefore proactively inquire with patients about current barriers or facilitators of adherence to HIV medications," they write.