Success of HIV Treatment May Be Undercounted, New Study Says

Traditional methods of counting patients being treated for HIV may underestimate the success of treatment, a new AHRQ-funded study found. The study examined the HIV continuum of care, which consists of diagnosis, linkage to and retention in care, receipt of antiretroviral therapy and suppression of the virus. Steps in this continuum are typically calculated in a conditional manner, with the number of people completing the prior step serving as the base population for the next step. However, researchers hypothesized, this approach may underestimate the prevalence of viral suppression. In this study, researchers followed 17,140 patients between 2010 and 2012, classifying them as to whether they completed the continuum of care or skipped steps in the process. They found that the virus was suppressed in some patients who had minimal contact with providers. Ignoring this group, researchers said, underestimates the proportion of patients suppressed by 13 percent. The article and abstract, “The HIV Care Continuum: Changes over Time in Retention in Care and Viral Suppression,” were published June 18 in the journal PLOS One.

The HIV Care Continuum: Changes over Time in Retention in Care and Viral Suppression. - PubMed - NCBI

2015 Jun 18;10(6):e0129376. doi: 10.1371/journal.pone.0129376. eCollection 2015.

The HIV Care Continuum: Changes over Time in Retention in Care and Viral Suppression.

Yehia BR1, Stephens-Shields AJ2, Fleishman JA3, Berry SA4, Agwu AL4, Metlay JP5, Moore RD4, Christopher Mathews W6, Nijhawan A7, Rutstein R8, Gaur AH9, Gebo KA4; HIV Research Network.

Author information

Abstract

BACKGROUND:

The HIV care continuum (diagnosis, linkage to care, retention in care, receipt of antiretroviral therapy (ART), viral suppression) has been used to identify opportunities for improving the delivery of HIV care. Continuum steps are typically calculated in a conditional manner, with the number of persons completing the prior step serving as the base population for the next step. This approach may underestimate the prevalence of viral suppression by excluding patients who are suppressed but do not meet standard definitions of retention in care. Understanding how retention in care and viral suppression interact and change over time may improve our ability to intervene on these steps in the continuum.

METHODS:

We followed 17,140 patients at 11 U.S. HIV clinics between 2010-2012. For each calendar year, patients were classified into one of five categories: (1) retained/suppressed, (2) retained/not-suppressed, (3) not-retained/suppressed, (4) not-retained/not-suppressed, and (5) lost to follow-up (for calendar years 2011 and 2012 only). Retained individuals were those completing ≥2 HIV medical visits separated by ≥90 days in the year. Persons not retained completed ≥1 HIV medical visit during the year, but did not meet the retention definition. Persons lost to follow-up had no HIV medical visits in the year. HIV viral suppression was defined as HIV-1 RNA ≤200 copies/mL at the last measure in the year. Multinomial logistic regression was used to determine the probability of patients' transitioning between retention/suppression categories from 2010 to 2011 and 2010 to 2012, adjusting for age, sex, race/ethnicity, HIV risk factor, insurance status, CD4 count, and use of ART.

RESULTS:

Overall, 65.8% of patients were retained/suppressed, 17.4% retained/not-suppressed, 10.0% not-retained/suppressed, and 6.8% not-retained/not-suppressed in 2010. 59.5% of patients maintained the same status in 2011 (kappa=0.458) and 53.3% maintained the same status in 2012 (kappa=0.437).

CONCLUSIONS:

Not counting patients not-retained/suppressed as virally suppressed, as is commonly done in the HIV care continuum, underestimated the proportion suppressed by 13%. Applying the care continuum in a longitudinal manner will enhance its utility.