The Impact of Comorbidities on Medication Adherence among People Living with HIV

Given the major public health implication of HIV medication non-adherence, it is crucially important to determine and understand the factors associated with adherence. Previous research has recognized individual, psychosocial, and environmental factors as important barriers to medication adherence in people living with HIV/AIDS; however, little attention has been given to the effect of comorbidities, as a patient factor, and the significant challenges created by multiple diseases and treatment regimens on HIV medication adherence. Poor understanding of the role of comorbidities in medication adherence limits the ability to treat people living with HIV effectively. This study attempted to fill the gap in the literature by investigating three aims. The first aim is the assessment of the patterns of comorbidity across racial and ethnic groups who are HIV positive and compared them to the patterns of those who are HIV negative. The second aim is the determination of the association between HIV medication adherence and comorbidities. The third aim is the analysis of how social and medical characteristics mediate the association between comorbidities and HIV medication adherence.^ This study employed a secondary data analysis of the Veterans Aging Cohort Study (VACS) to examine the patterns of comorbidity as well as the direct and mediate relationship between comorbid disease and HIV medication adherence. The study findings show that comorbidity patterns are related to race rather than HIV status, which may be an indication of disparities within society and the healthcare system. Further, HIV-infected veterans with cardiovascular disease had higher HIV medication adherence than HIV-infected veterans without cardiovascular disease whereas veterans with substance abuse were less adherent than HIV-infected veterans without substance abuse. Finally, social support and medical characteristics did not mediate the relationship between cardiovascular disease, substance abuse, and adherence. ^ Although this study found partial support of proposition that there is an association between comorbidity and HIV medication adherence, this may be a reflection of the quality of care received by veterans at the VA. Future research would need to be done to determine the association between comorbidity and HIV medication adherence outside of the VA healthcare system. ^