Correlates of self-reported nonadherence to antiretroviral therapy in HIV-infected patients: the Swiss HIV Cohort Study.
BACKGROUND
Adherence is one of the most crucial issues in the clinical management of HIV-infected patients receiving antiretroviral therapy (ART).


METHODS
A 2-item adherence questionnaire was introduced into the Swiss HIV Cohort Study in July 2003. All 3607 eligible patients were on ART for > or =6 months and their current regimen for > or =1 month. Three definitions of nonadherence were considered: missing > or =1 dose, missing > or =2 doses, and taking <95% of doses in the past 4 weeks.


RESULTS
Over 30% of patients reported missing > or =1 dose, 14.9% missed > or =2 doses, and 7.1% took <95% of doses in the previous 4 weeks. The rate of drug holidays was 5.8%. Whether using more or less conservative definitions of nonadherence, younger age, living alone, number of previous regimens, and boosted protease inhibitor regimens were independent factors associated with nonadherence. There was a significant association between optimal viral suppression and nonadherence as well as a significant linear trend in optimal viral suppression by missed doses.


CONCLUSIONS
Younger age, lack of social support, and complexity of therapy are important factors that are related to nonadherence with ART. Investment in behavioral dimensions of HIV is crucial to improve adherence in ART recipients.
Basel Institute for Clinical Epidemiology, University Hospital Basel, CH-4056 Basel, Switzerland.
Tracy R
TR
Glass
Sabina
S
De Geest
Rainer
R
Weber
Pietro L
PL
Vernazza
Martin
M
Rickenbach
Hansjakob
H
Furrer
Enos
E
Bernasconi
Matthias
M
Cavassini
Bernard
B
Hirschel
Manuel
M
Battegay
Heiner C
HC
Bucher
D000328:Adult; D000367:Age Factors; D019380:Anti-HIV Agents / Q000008:administration & dosage* / Q000627:therapeutic use; D023241:Antiretroviral Therapy, Highly Active; D015331:Cohort Studies; D005260:Female; D015658:HIV Infections / Q000188:drug therapy*; D006801:Humans; D008019:Life Style; D008297:Male; D012307:Risk Factors; D011795:Surveys and Questionnaires; D016312:Treatment Refusal / Q000706:statistics & numerical data*; D019562:Viral Load
D019380:Anti-HIV Agents