Drug Side Effects and Retention on HIV Treatment: a Regression Discontinuity Study of Tenofovir Implementation in South Africa and Zambia

Drug Side Effects and Retention on HIV Treatment: a Regression Discontinuity Study of Tenofovir... Abstract Tenofovir is less toxic than other nucleoside reverse transcriptase inhibitors used in antiretroviral therapy (ART) and may improve retention of HIV-infected patients on ART. We assessed the impact of national guideline changes in South Africa (2010) and Zambia (2007) recommending tenofovir in first-line ART. We applied regression discontinuity in a prospective cohort of 52,294 HIV-infected adults initiating first-line ART within ±12-months of each guideline change. We compared outcomes in patients presenting just before/after the guideline changes using local linear regression and estimated intention-to-treat effects on initiation of tenofovir, retention in care, and other treatment outcomes at 24-months. We assessed complier causal effects among patients starting tenofovir. The new guidelines increased the percentage of patients initiating tenofovir in South Africa (risk difference (RD): 81%; 95% confidence interval (CI): 73, 89) and Zambia (RD: 42%; 95% CI: 38, 45). With the guideline change, single-drug substitutions decreased substantially in South Africa (RD: −15%; 95% CI:−18, −12). Starting tenofovir also reduced attrition in Zambia (intent-to-treat RD: −1.8%; 95% CI: −3.5, −0.1, complier relative risk = 0.74) but not in South Africa (RD: −0.9%; 95% CI: −5.9, 4.1, Complier Relative Risk = 0.94). These results highlight the importance of reducing side effects for increasing retention in care, as well as the differences in population impact of policies with heterogeneous treatment effects implemented in different contexts. antiretroviral therapy, human immunodeficiency virus, low- and middle-income countries, regression discontinuity, Southern Africa, stavudine, tenofovir, treatment outcomes, Zambia © The Author(s) 2018. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/about_us/legal/notices) http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png American Journal of Epidemiology Oxford University Press

Drug Side Effects and Retention on HIV Treatment: a Regression Discontinuity Study of Tenofovir Implementation in South Africa and Zambia

Loading next page...
 
/lp/ou_press/drug-side-effects-and-retention-on-hiv-treatment-a-regression-wVDps6AMt0
Publisher
Oxford University Press
Copyright
© The Author(s) 2018. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
ISSN
0002-9262
eISSN
1476-6256
D.O.I.
10.1093/aje/kwy093
Publisher site
See Article on Publisher Site

Abstract

Abstract Tenofovir is less toxic than other nucleoside reverse transcriptase inhibitors used in antiretroviral therapy (ART) and may improve retention of HIV-infected patients on ART. We assessed the impact of national guideline changes in South Africa (2010) and Zambia (2007) recommending tenofovir in first-line ART. We applied regression discontinuity in a prospective cohort of 52,294 HIV-infected adults initiating first-line ART within ±12-months of each guideline change. We compared outcomes in patients presenting just before/after the guideline changes using local linear regression and estimated intention-to-treat effects on initiation of tenofovir, retention in care, and other treatment outcomes at 24-months. We assessed complier causal effects among patients starting tenofovir. The new guidelines increased the percentage of patients initiating tenofovir in South Africa (risk difference (RD): 81%; 95% confidence interval (CI): 73, 89) and Zambia (RD: 42%; 95% CI: 38, 45). With the guideline change, single-drug substitutions decreased substantially in South Africa (RD: −15%; 95% CI:−18, −12). Starting tenofovir also reduced attrition in Zambia (intent-to-treat RD: −1.8%; 95% CI: −3.5, −0.1, complier relative risk = 0.74) but not in South Africa (RD: −0.9%; 95% CI: −5.9, 4.1, Complier Relative Risk = 0.94). These results highlight the importance of reducing side effects for increasing retention in care, as well as the differences in population impact of policies with heterogeneous treatment effects implemented in different contexts. antiretroviral therapy, human immunodeficiency virus, low- and middle-income countries, regression discontinuity, Southern Africa, stavudine, tenofovir, treatment outcomes, Zambia © The Author(s) 2018. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/about_us/legal/notices)

Journal

American Journal of EpidemiologyOxford University Press

Published: May 15, 2018

There are no references for this article.

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create lists to
organize your research

Export lists, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off