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Timing is everything: Antiretroviral nonadherence is associated with impairment in time-based prospective memory

Published online by Cambridge University Press:  01 January 2009

STEVEN PAUL WOODS ,
MATTHEW S. DAWSON ,
ERICA WEBER ,
SARAH GIBSON ,
IGOR GRANT  and
J. HAMPTON ATKINSON
STEVEN PAUL WOODS*
Affiliation:
Department of Psychiatry, School of Medicine, University of California, San Diego, La Jolla, California
MATTHEW S. DAWSON
Affiliation:
Department of Psychiatry, School of Medicine, University of California, San Diego, La Jolla, California
ERICA WEBER
Affiliation:
Department of Psychiatry, School of Medicine, University of California, San Diego, La Jolla, California
SARAH GIBSON
Affiliation:
Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, California
IGOR GRANT
Affiliation:
Department of Psychiatry, School of Medicine, University of California, San Diego, La Jolla, California
J. HAMPTON ATKINSON
Affiliation:
Department of Psychiatry, School of Medicine, University of California, San Diego, La Jolla, California Psychiatry Service, VA San Diego Healthcare System, San Diego, California
*
*Correspondence and reprint requests to: Steven Paul Woods, HIV Neurobehavioral Research Center, Department of Psychiatry (0847), University of California, San Diego, 150 West Washington Street, 2nd floor, San Diego, California 92103. E-mail: spwoods@ucsd.edu.
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Abstract

Nonadherence to combination antiretroviral (ARV) therapies (cART) is highly prevalent and significantly increases the risk of adverse human immunodeficiency virus (HIV) disease outcomes. The current study evaluated the hypothesis that prospective memory—a dissociable aspect of episodic memory describing the ability to execute a future intention—plays an important role in successful cART adherence. Seventy-nine individuals with HIV infection who were prescribed at least one ARV medication underwent a comprehensive neuropsychological and neuromedical evaluation prior to completing a 1-month observation of their cART adherence as measured by electronic medication monitoring. Nonadherent individuals (n = 31) demonstrated significantly poorer prospective memory functioning as compared to adherent persons (n = 48), particularly on an index of time-based ProM (i.e., elevated loss of time errors). Deficits in time-based prospective memory were independently predictive of cART nonadherence, even after considering the possible influence of established predictors of adherence, such as general cognitive impairment (e.g., retrospective learning and memory) and psychiatric comorbidity (e.g., depression). These findings extend a nascent literature showing that impairment in time-based prospective memory significantly increases the risk of medication nonadherence and therefore may guide the development of novel strategies for intervention. (JINS, 2009, 15, 42–52.)

Keywords

Human immunodeficiency virusAIDS dementia complexNeuropsychological testsCognitive sciencePatient complianceTime perception
Type
Research Articles
Information
Journal of the International Neuropsychological Society , Volume 15 , Issue 1 , January 2009 , pp. 42 - 52
Copyright
Copyright © INS 2009

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