Although patient adherence is often difficult for a variety
of patient, provider, and health care system-related factors,
it is essential to optimal patient outcomes. Thus, health care
providers and researchers must identify ways to enhance
medication adherence. One important way is to identify
the factors that contribute to poor adherence.
Barriers to medication adherence were the only significant
predictor of all 3 indicators of objectively measured
adherence. In addition to barriers to medication adherence,
condition-related factors (ie, NYHA) and socioeconomic
factors (ie, ethnicity, financial status, and social support)
were related to at least 1 indicator of adherence. The
MAM has been proposed as a model of medication adherence
in HF, although it has not been previously tested in
this sample. This study provides a first step in testing the
model and demonstrates that some of the conceptual relationships
proposed by the MAM are valid, whereas others
are not. Further studies are needed to fully investigate the
relationships among variables in the MAM. These findings
have important implications for clinicians caring for
patients with HF. Assessing patients’ barriers to taking prescribed
medications should be the first step in implementing
any intervention to improve medication adherence.
Minorities and those who had more severe symptoms as
reflected by NYHA functional class, lower income, and less social support should be considered at high risk for
medication nonadherence. The findings of this study provide
clinicians and researchers a theoretic basis for effective
interventions to improve medication adherence and
clinical outcomes in patients with HF