Abstract
OBJECTIVE: The HIV/AIDS epidemic disproportionately involves socially vulnerable populations. Since 2001, the proportion of foreign-born patients served by the Northern Alberta HIV Program has increased. Our study aimed to evaluate antiretroviral therapy (ART) outcomes among HIV-infected foreign-born patients in northern Alberta, Canada, prescribed once-daily ART.
METHODS: We utilized a two-part retrospective cohort study to compare ART outcomes of foreign-born and Canadian-born Aboriginal patients compared to Canadian-born non-Aboriginal patients. Part 1 utilized logistic regression to compare the odds of experiencing initial virological suppression of foreign-born (40%) and Canadian-born Aboriginal patients (27%) compared with Canadian-born non-Aboriginal patients (33%). Part 2 used survival analysis to compare the rate of ART failure by country of origin among patients who achieved initial virological suppression in Part 1.
RESULTS: Our study sample included 322 treatment-naïve patients (122 foreign-born). For Part 1, 261 patients achieved initial virological suppression within six months of initiating ART. After controlling for age, treatment regimen, HIV risk exposure, and calendar year compared to Canadian-born non-Aboriginal patients, the odds of achieving initial virological suppression were significantly lower for Canadian-born Aboriginal patients (OR=0.44, 95% CI: 0.20-0.96); and similar for foreign-born patients (OR=0.76, 95% CI: 0.33-1.73). Part 2 included 261 patients who were followed for 635.1 person-years. Adjusting for age, sex, baseline CD4 cell count, and drug regimen, compared to Canadian-born non-Aboriginal patients, Canadian-born Aboriginal and foreign-born patients had similar rates of virological failure after achieving initial virological suppression (HR=1.54, 95% CI: 0.38-6.18; HR=0.49, 95% CI: 0.11-2.20, respectively).
CONCLUSIONS: Our study indicated that ART outcomes among Alberta-based foreign-born patients are similar to those among Canadian-born non-Aboriginal patients. Our results, however, suggested that Canadian-born Aboriginal patients had poorer treatment outcomes compared to Canadian-born non-Aboriginal patients. It is imperative, therefore, that clinicians, researchers and community members better understand reasons for poor ART outcomes among Canadian-born Aboriginal patients in northern Alberta.
Key Words: Antiretroviral therapy, emigrants and immigrants, HIV-1, treatment outcomes, Canada
Résumé
OBJECTIF : L’épidémie de VIH et de sida frappe démesurément les populations socialement vulnérables. Depuis 2001, la proportion de patients nés à l’étranger servis par le programme de lutte contre le VIH du nord de l’Alberta a augmenté. Notre étude visait à évaluer les effets de la thérapie antirétrovirale (TAR) dans le nord de l’Alberta, au Canada, chez des patients infectés par le VIH nés à l’étranger auxquels on avait prescrit une dose quotidienne d’antirétroviraux.
MÉTHODE : Nous avons utilisé une étude de cohorte rétrospective en deux volets pour comparer les effets de la TAR chez les patients nés à l’étranger et les patients autochtones nés au Canada et chez les patients non autochtones nés au Canada. Le 1er volet a fait appel à la régression logistique pour comparer la probabilité d’une suppression virale initiale chez les patients nés à l’étranger (40 %) et les patients autochtones nés au Canada (27 %) et chez les patients non autochtones nés au Canada (33 %). Le 2e volet a fait appel à l’analyse de survie pour comparer le taux d’échec de la TAR selon le pays d’origine des patients ayant obtenu une suppression virale initiale durant le 1er volet.
RÉSULTATS : Notre échantillon d’étude comportait 322 patients naïfs de traitement (dont 122 nés à l’étranger). Pour le 1er volet, 261 patients ont obtenu une suppression virale initiale moins de six mois après le début de la TAR. Compte tenu de l’âge, du schéma thérapeutique, du risque d’exposition au VIH et de l’année civile, comparativement aux patients non autochtones nés au Canada, la probabilité d’obtenir une suppression virale initiale était significativement plus faible chez les patients autochtones nés au Canada (RC=0,44, IC de 95 %: 0,20-0,96); et similaire à celle des patients nés à l’étranger (RC=0,76, IC de 95 %: 0,33-1,73). Le 2e volet incluait 261 patients, suivis sur 635,1 annéespersonne. Compte tenu de l’âge, du sexe, de la numération des lymphocytes CD4 au départ et du régime posologique, comparativement aux patients non autochtones nés au Canada, les patients autochtones nés au Canada et les patients nés à l’étranger avaient des taux d’échec virologique similaires après la suppression virale initiale (indice de risque (IR)=1,54, IC de 95 %: 0,38-6,18; IR=0,49, IC de 95 %: 0,11-2,20, respectivement).
CONCLUSIONS : Notre étude indique que les effets de la TAR chez les patients de l’Alberta nés à l’étranger sont semblables à ceux observés chez les patients non autochtones nés au Canada. Par contre, nos résultats donnent à penser que chez les patients autochtones nés au Canada, les effets du traitement sont moins bons que chez les patients non autochtones nés au Canada. Il est donc impératif que les cliniciens, les chercheurs et le public comprennent mieux les raisons de l’inefficacité relative de la TAR chez les patients autochtones du nord de l’Alberta nés au Canada.
Mots Clés: thérapie antirétrovirale, émigrants et immigrants, VIH-1, effets physiologiques des médicaments, Canada
Footnotes
Acknowledgements: The authors wish to recognize the participants involved in this study. We thank the clinicians at the NAP for their help and support with this research, and Yutaka Yasui for his statistical support.
Conflict of Interest: None to declare.
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