A temporal and dose-response association between alcohol consumption and medication adherence among veterans in care.
BACKGROUND
Previous studies have shown that alcohol consumption is associated with decreased medication adherence, but this association may be confounded by characteristics common among those who drink heavily and those who fail to adhere (e.g., illicit drug use). Our objective was to determine whether there are temporal and dose-response relationships between alcohol consumption and poor adherence.


METHODS
We administered telephone interview surveys to participants in the Veterans Aging Cohort Study, an eight-site observational study of HIV+ and matched HIV- veterans in care, to determine whether alcohol consumption on a particular day was associated with nonadherence to prescribed medications on that same day. We used the Time Line Follow Back to measure alcohol consumption and the Time Line Follow Back Modified for Adherence to measure adherence. Individuals were categorized as abstainers (no alcohol in past 30 days), nonbinge drinkers (alcohol in past 30 days but < or =four standard drinks on each day), or binge drinkers (> or =five standard drinks on at least one day).


RESULTS
Among 2702 respondents, 1582 (56.6%) were abstainers, 931 (34.5%) were nonbinge drinkers, and 239 (8.9%) were binge drinkers. Abstainers missed medication doses on 2.4% of surveyed days. Nonbinge drinkers missed doses on 3.5% of drinking days, 3.1% of postdrinking days, and 2.1% of nondrinking days (p < 0.001 for trend), and this trend was more pronounced among HIV+ individuals than HIV- individuals. Binge drinkers missed doses on 11.0% of drinking days, 7.0% of postdrinking days, and 4.1% of nondrinking days (p < 0.001 for trend), and this trend was comparably strong for HIV+ and HIV- individuals.


CONCLUSIONS
Among veterans in care, self-reported alcohol consumption demonstrates a temporal and dose-response relationship to poor adherence. HIV+ individuals may be particularly sensitive to alcohol consumption.
Braithwaite
R Scott
RS
West Haven Veterans Administration Medical Center and Yale University School of Medicine, West Haven, Connecticut 06516, USA. Ronald.brathwaite@med.va.gov
McGinnis
Kathleen A
KA
Conigliaro
Joseph
J
Maisto
Stephen A
SA
Crystal
Stephen
S
Day
Nancy
N
Cook
Robert L
RL
Gordon
Adam
A
Bridges
Michael W
MW
Seiler
Jason F S
JF
Justice
Amy C
AC
D000428:Alcohol Drinking / Q000009:adverse effects* / Q000523:psychology; D000437:Alcoholism / Q000523:psychology; D019380:Anti-HIV Agents / Q000008:administration & dosage*; D015331:Cohort Studies; D005260:Female; D006679:HIV Seropositivity / Q000188:drug therapy* / Q000523:psychology; D006801:Humans; D007407:Interviews as Topic; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D013223:Statistics as Topic; D016312:Treatment Refusal / Q000523:psychology*; D014728:Veterans / Q000523:psychology*
D019380:Anti-HIV Agents