Measuring adherence to antiretroviral treatment in resource-poor settings: the clinical validity of key indicators.
BACKGROUND
Access to antiretroviral therapy has dramatically expanded in Africa in recent years, but there are no validated approaches to measure treatment adherence in these settings.


METHODS
In 16 health facilities, we observed a retrospective cohort of patients initiating antiretroviral therapy. We constructed eight indicators of adherence and visit attendance during the first 18 months of treatment from data in clinic and pharmacy records and attendance logs. We measured the correlation among these measures and assessed how well each predicted changes in weight and CD4 count.


RESULTS
We followed 488 patients; 63.5% had 100% coverage of medicines during follow-up; 2.7% experienced a 30-day gap in treatment; 72.6% self-reported perfect adherence in all clinic visits; and 19.9% missed multiple clinic visits. After six months of treatment, mean weight gain was 3.9 kg and mean increase in CD4 count was 138.1 cells/mm3.Dispensing-based adherence, self-reported adherence, and consistent visit attendance were highly correlated. The first two types of adherence measure predicted gains in weight and CD4 count; consistent visit attendance was associated only with weight gain.


CONCLUSIONS
This study demonstrates that routine data in African health facilities can be used to monitor antiretroviral adherence at the patient and system level.
Ross-Degnan
Dennis
D
Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston MA, USA. Dennis_Ross-Degnan@hms.harvard.edu
Pierre-Jacques
Marsha
M
Zhang
Fang
F
Tadeg
Hailu
H
Gitau
Lillian
L
Ntaganira
Joseph
J
Balikuddembe
Robert
R
Chalker
John
J
Wagner
Anita K
AK
D000328:Adult; D000351:Africa, Eastern; D044966:Anti-Retroviral Agents / Q000009:adverse effects / Q000627:therapeutic use*; D018791:CD4 Lymphocyte Count; D015331:Cohort Studies; D005260:Female; D015658:HIV Infections / Q000188:drug therapy*; D006268:Health Facilities; D006801:Humans; D008297:Male; D010349:Patient Compliance / Q000706:statistics & numerical data*; D010865:Pilot Projects; D012189:Retrospective Studies; D015430:Weight Gain
D044966:Anti-Retroviral Agents