How well do clinicians estimate patients' adherence to combination antiretroviral therapy?
OBJECTIVE
Adherence to combination antiretroviral therapy is critical for clinical and virologic success in HIV-infected patients. To combat poor adherence, clinicians must identify nonadherent patients so they can implement interventions. However, little is known about the accuracy of these assessments. We sought to describe the accuracy of clinicians' estimates of patients' adherence to combination antiretroviral therapy.


METHODS
Public HIV clinic.


METHODS
Prospective cohort study. During visits, we asked clinicians (nurse practitioners, residents and fellows, and their supervising attending physicians) to estimate the percentage of antiretroviral medication taken by patients over the last 4 weeks and predicted adherence over the next 4 weeks. Adherence was measured using electronic monitoring devices, pill counts, and self-reports, which were combined into a composite adherence measure.


METHODS
Clinicians estimated 464 episodes of adherence in 82 patients.


RESULTS
Among the 464 adherence estimates, 264 (57%) were made by principal care providers (31% by nurse practitioners, 15% by fellows, 6% by residents, and 5% by staff physicians) and 200 (43%) by supervising attending physicians. Clinicians' overestimated measured adherence by 8.9% on average (86.2% vs 77.3%). Greater clinician inaccuracy in adherence prediction was independently associated with higher CD4 count nadir (1.8% greater inaccuracy for every 100 CD4 cells, P=.005), younger patient age (3.7% greater inaccuracy for each decade of age, P=.02), and visit number (P=.02). Sensitivity of detecting nonadherent patients was poor (24% to 62%, depending on nonadherence cutoff). The positive predictive value of identifying a patient as nonadherent was 76% to 83%.


CONCLUSIONS
Clinicians tend to overestimate medication adherence, inadequately detect poor adherence, and may therefore miss important opportunities to intervene to improve antiretroviral adherence.
Miller
Loren G
LG
Division of Infectious Diseases, Harbor-UCLA Medical Center, Torrance Calif., 90509 USA. lgmiller@ucla.edu
Liu
Honghu
H
Hays
Ron D
RD
Golin
Carol E
CE
Beck
C Keith
CK
Asch
Steven M
SM
Ma
Yingying
Y
Kaplan
Andrew H
AH
Wenger
Neil S
NS
D000328:Adult; D019380:Anti-HIV Agents / Q000008:administration & dosage*; D023241:Antiretroviral Therapy, Highly Active; D001291:Attitude of Health Personnel; D015331:Cohort Studies; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000523:psychology*; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D008297:Male; D008875:Middle Aged; D010349:Patient Compliance; D010358:Patient Participation; D011369:Professional-Patient Relations; D011446:Prospective Studies; D013997:Time Factors
D019380:Anti-HIV Agents