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The effect of churn on "community viral load" in a well-defined regional population

Hartmut B Krentz1, M John Gill

  • 1*Southern Alberta Clinic, Calgary, Canada; and †Department of Medicine, University of Calgary, Calgary, Canada.

Journal of Acquired Immune Deficiency Syndromes (1999)
|September 20, 2013
PubMed

Insights

Community viral load (CVL) did not decrease with increased highly active antiretroviral therapy (HAART) use. Patient movement, or churn, limited CVL

Area of Science:

  • Public Health
  • Infectious Disease Epidemiology
  • HIV/AIDS Research

Background:

  • Community viral load (CVL) quantifies transmissible HIV and monitors highly active antiretroviral therapy (HAART) impact.
  • The influence of patient churn on CVL has not been previously investigated.

Purpose of the Study:

  • To analyze the impact of patient churn on community viral load (CVL) and its utility in assessing HAART effectiveness in reducing HIV transmission.

Main Methods:

  • Annual CVL was calculated for the entire HIV population in southern Alberta (2001-2010).
  • Subpopulation CVL was analyzed in 2009, categorizing patients by care status (continuous, newly diagnosed, new to region, moved away, returned, lost to follow-up).
  • Viral load suppression was defined as <50 copies/mL (undetectable) and <200 copies/mL (suppressed).

Main Results:

  • Despite increased HAART uptake (62% to 81%) and viral load suppression (49% to 72%), total CVL remained stable after 2003.
  • New HIV diagnoses increased from 4.4 to 5.8 per 100,000 annually.
  • In 2009, newly diagnosed patients and those with churn (transfers, lost to follow-up) contributed disproportionately to CVL (37.5% and 33%, respectively), while continuously cared-for patients (79%) contributed 29.5%.

Conclusions:

  • Increased HAART coverage did not reduce CVL or new HIV diagnoses in this population.
  • Patient churn significantly complicates the use of CVL as a metric for evaluating HAART's impact on HIV transmission reduction.
Abstract

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