A Guide to Primary Care of People with HIV/AIDS - Canadian Public ...

A Guide to Primary Care of People with HIV/AIDS
Chapter 5: Antiretroviral Therapy
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• Intermittent therapy The plan with intermittent
therapy is to periodically discontinue treatment on a
prearranged schedule, such as 1 week on and 1 week
off or 5 days of treatment followed by a weekend
off. The theory is that when therapy is discontinued
there is usually sustained viral suppression for 10-14
days and treatment is restarted while the virus is still
suppressed. This strategy could potentially reduce
treatment-associated side effects and cost. Although
the initial experience has been limited but promising,
the strategy cannot be recommended until more
substantial experience is gained.
• Pulse therapy With this strategy, therapy is
discontinued when the CD4 cell count increases to a
level that makes the patient and physician comfortable
doing so and is restarted when the CD4 count declines
to a worrisome level. Initial experience has generally
been that the viral load returns within 2 weeks and
the CD4 cell count declines rapidly and then plateaus.
Most experts restart therapy when the CD4 cell count
reaches 350/mm 3 , but this strategy has not been
systematically studied. Nevertheless, it does appear
that there is no penalty in terms of resistance and
the period off therapy is often 1-2 years, depending
to a large extent on the CD4 cell count at the time
treatment is discontinued and on the pre-therapy
CD4 nadir. The patient must be warned that viral
loads will return to pre-therapy levels, with important
implications for risk of HIV transmission to others.
KEY POINTS
The major indicator for the speed of
progression in early stage disease is the
viral load, which dictates the speed of
CD4 cell decline. The major indicator for
the risk of HIV-associated complications
is the CD4 cell count.
ART is directed toward preventing
HIV-associated complications and
hospitalizations and improving quality of
life and survival.
ART does not cure HIV infection, is
expensive, is associated with substantial
risks of short-term and long-term toxicity,
and requires a level of adherence that is
unmatched with any other antimicrobial
therapy.
ART is recommended when there are HIVassociated
symptoms or when the CD4
count is 25-50/mm 3 at 6-12 months), or
clinical (new AIDS-defining OI after >3
months of therapy).
Treatment is changed for drug intolerance
(substitution) or virologic failure
(selection by resistance tests).
The 3 factors that consistently predict
outcome are CD4 cell count, patient
adherence, and provider experience.
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U.S. Department of Health and Human Services, Health Resources and Services Administration, HIV/AIDS Bureau