Relationship between self-reported adherence, antiretroviral drug concentration measurement and self-reported symptoms in patients treated for HIV-1 infection.
BACKGROUND
The aim of the study was to explore relationships between self-reported adherence, antiretroviral drug concentration measurement (TDM) and self-reported symptoms.


METHODS
We systematically administered to human immunodeficiency (HIV)-infected outpatients a questionnaire evaluating measures of self-reported adherence (missing doses during last week, deviations from the prescribed timing of therapy, self-initiated discontinuations for > 24 or 48 h, exhausting drugs and present sense of how patients are taking therapy) and a panel of referred symptoms (a symptom score was built summing self-reported scores for each listed symptom). We selected patients who completed the questionnaire and also had a TDM (mainly reflecting adherence in the past few days or weeks), thus comparing these two tools as measures of adherence.


RESULTS
A total of 130 patients (64.6% males, median age 44 years, 76.2% with HIV RNA < 50 copies/ml, median CD4 540 cells/μl) were included. Mean self-reported adherence (on a 0-100 visual analogue scale) was 80% (standard deviation, 18.7). Drug concentration was subtherapeutic in 16 patients (12.3%), of which 7 (5.4%) had undetectable drug levels (< 0.05 mg/L). Of these last seven patients, five (71.4%) reported an adherence below 80%. In a multivariable analysis, females and patients with undetectable drug levels (mean change -18.43%, 95% confidence intervals (CIs) -31.83 to -5.03, p = 0.007) showed a lower self-reported adherence, while those with HIV RNA < 50 copies/ml showed a higher adherence. Lower self-reported adherence (odds ratio 0.62 per 10% increase, 95% CI = 0.43-0.89, p = 0.009) and longer time from last drug intake were independently related to the development of undetectable drug levels. We also found that a higher symptom score was associated with a lower self-reported adherence and with a higher proportion of undetectable drug levels.


CONCLUSIONS
Self-reported adherence and TDM showed a correlation and seemed to be comparable tools for adherence estimation. Self-reported symptoms were associated with lower adherence and undetectable drug levels.
a From the Institute of Clinical Infectious Diseases, Catholic University of Sacred Heart , Rome , Italy.
Massimiliano
M
Fabbiani
a From the Institute of Clinical Infectious Diseases, Catholic University of Sacred Heart , Rome , Italy.
Simona
S
Di Giambenedetto
a From the Institute of Clinical Infectious Diseases, Catholic University of Sacred Heart , Rome , Italy.
Antonella
A
Cingolani
a From the Institute of Clinical Infectious Diseases, Catholic University of Sacred Heart , Rome , Italy.
Iuri
I
Fanti
a From the Institute of Clinical Infectious Diseases, Catholic University of Sacred Heart , Rome , Italy.
Manuela
M
Colafigli
a From the Institute of Clinical Infectious Diseases, Catholic University of Sacred Heart , Rome , Italy.
Enrica
E
Tamburrini
a From the Institute of Clinical Infectious Diseases, Catholic University of Sacred Heart , Rome , Italy.
Roberto
R
Cauda
b Institute of Pharmacology, Catholic University of Sacred Heart , Rome , Italy.
Pierluigi
P
Navarra
a From the Institute of Clinical Infectious Diseases, Catholic University of Sacred Heart , Rome , Italy.|c Infectious Diseases Unit, Siena University Hospital , Italy.
Andrea
A
De Luca
a From the Institute of Clinical Infectious Diseases, Catholic University of Sacred Heart , Rome , Italy.
Rita
R
Murri
D000328:Adult; D019380:Anti-HIV Agents / Q000009:adverse effects / Q000097:blood* / Q000627:therapeutic use*; D023241:Antiretroviral Therapy, Highly Active; D004305:Dose-Response Relationship, Drug; D016903:Drug Monitoring; D005260:Female; D015658:HIV Infections / Q000188:drug therapy*; D015497:HIV-1 / Q000187:drug effects / Q000235:genetics; D006801:Humans; D008297:Male; D055118:Medication Adherence; D008875:Middle Aged; D010599:Pharmacokinetics; D057566:Self Report; D011795:Surveys and Questionnaires
D019380:Anti-HIV Agents
Adherence; HIV; pharmacokinetic; self-reported symptoms; therapeutic drug monitoring