Non-medically supervised treatment interruptions among participants in a universally accessible antiretroviral therapy programme.
BACKGROUND
We examined clinical outcomes, patient characteristics and trends over time of non-medically supervised treatment interruptions (TIs) from a free-of-charge antiretroviral therapy (ART) programme in British Columbia (BC), Canada.


METHODS
Data from ART-naïve individuals > or =18 years old who initiated triple combination highly active antiretroviral therapy (HAART) between January 2000 and June 2006 were analysed. Participants having > or =3 month gap in HAART coverage were defined as having a TI. Cox proportional hazards modelling was used to examine factors associated with TIs and to examine factors associated with resumption of treatment.


RESULTS
A total of 1707 participants were study eligible and 643 (37.7%) experienced TIs. TIs within 1 year of ART initiation decreased from 29% of individuals in 2000 to 19% in 2006 (P<0.001). TIs were independently associated with a history of injection drug use (IDU) (P=0.02), higher baseline CD4 cell counts (P<0.001), hepatitis C co-infection (P<0.001) and the use of nelfinavir (NFV) (P=0.04) or zidovudine (ZDV)/lamivudine (3TC) (P=0.009) in the primary HAART regimen. Male gender (P<0.001), older age (P<0.001), AIDS at baseline (P=0.008) and having a physician who had prescribed HAART to fewer patients (P=0.03) were protective against TIs. Four hundred and eighty-eight (71.9%) participants eventually restarted ART with male patients and those who developed an AIDS-defining illness prior to their TI more likely to restart therapy. Higher CD4 cell counts at the time of TI and unknown hepatitis C status were associated with a reduced likelihood of restarting ART.


CONCLUSIONS
Treatment interruptions were associated with younger, less ill, female and IDU participants. Most participants with interruptions eventually restarted therapy. Interruptions occurred less frequently in recent years.
Moore
D M
DM
British Columbia Centre for Excellence in HIV/AIDS, Vancouver, Canada. dmoore@cfenet.ubc.ca
Zhang
W
W
Yip
B
B
Genebat
M
M
Lima
V D
VD
Montaner
J S G
JS
Hogg
R S
RS
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D044966:Anti-Retroviral Agents / Q000627:therapeutic use*; D023241:Antiretroviral Therapy, Highly Active; D001955:British Columbia / Q000453:epidemiology; D018791:CD4 Lymphocyte Count; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000453:epidemiology / Q000276:immunology; D006297:Health Services Accessibility; D006526:Hepatitis C / Q000276:immunology; D006801:Humans; D008297:Male; D055118:Medication Adherence / Q000523:psychology; D011247:Pregnancy; D016016:Proportional Hazards Models; D015819:Substance Abuse, Intravenous / Q000150:complications / Q000534:rehabilitation; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult; D016903:Drug Monitoring
D044966:Anti-Retroviral Agents