Background
Health literacy is considered as the degree to which
individuals have the capacity to obtain, process and understand
basic information and services needed to make
appropriate decision regarding their health. Although many
studies have examined the association between health literacy
and medication adherence in chronic disease context, findings
have been contrasting. Medication adherence among people
living with HIV remains an important public health challenge,
despite recent simplified drug regimens. The main purpose of
this study was to review the association between health literacy
and adherence to Highly Active Antiretroviral Therapy
(HAART). Additionally, this review aimed to clarify whether
different adherence measures could influence that relationship.
Methods
Literature search was performed in PubMed and Scopus for
studies regarding health literacy and HAART adherence among
individuals HIV infected adult published between 1999 and
2013. Papers focused on drug users, pregnant women and
naive patients were excluded. Furthermore, only studies with a
measurement of health literacy with validated tools were
included. Reporting was conducted in the form recommended
in the Preferred Reporting Items for Systematic Reviews and
Meta-Analyses (PRISMA) statement and checklist.
Results
There were 57 potentially relevant articles from which a total of
7 studies concerning an overall population of 1274 were
included in the systematic review. Adherence was assessed
using objective measures (pharmacy refill records, electronic
event monitors and unannounced telephone-based pill counts)
in three articles; others papers used self-report tools or
interview. Two different validated instruments for measuring
literacy were reported. In three studies participants with lower
health literacy demonstrated poorer adherence compared to
individuals with higher literacy (33% of all population,
including 416 individuals). The association between health
literacy and adherence was not related to different HAART
adherence measurement.
Conclusions
Additional research was needed to pursue a better understanding
of the mechanism by which health literacy affects
medication adherence.
Key message
A better understanding of the impact of health literacy on
medication adherence is a public health priority in order to
safeguard vulnerable communities such as persons living
with HIV