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HIV, HAART and Older Patients
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This report discusses a study published in the January 3, 2003 issue of the
journal AIDS, which found that older patients responded as well to HAART as
younger patients. Numerous studies conducted before the HAART era have shown
that older individuals have a more severe HIV disease course and a shorter
survival rate, probably in relation to the presence of underlying conditions,
physiological decline in the competence of the immune system associated with
aging, and late diagnosis of HIV infection. It has been found that age is not
related to HAART outcome as reported in the studies discussed below; however,
the access to antiretroviral therapy was the only predictor of survival in a
study of a group of patients aged 50 years or older. Older individuals may
not get tested for HIV as often as younger people because doctors may not
think they are at risk and because the individuals themselves may not realize
they are at risk. But it appears clear that for years rates of HIV-infection
among older individuals are steadily increasing. As women and men age they
may not appreciate the risks of unprotected sex. In retirement communities
the risk for HIV-infection may not be appreciated and as a result individuals
may not feel the need to practice safe sex. As you will see from the study
results discussed below, aging is associated with a number of co-morbid
conditions and risk for more adverse events some of which may be associated
with HAART. We need more research addressing these concerns and evaluating
aging with HIV and HAART.
Study summary: The purpose of this study was to determine the impact of
highly active antiretroviral therapy (HAART) on the viro-immunological
response of older HIV-positive patients, researchers prospectively selected
58 older cases and 116 younger controls. The CD4 T-cell count at baseline was
lower in older folks, whereas the HIV viral load was similar in both groups.
Cases were more frequently affected by co-morbid conditions. Under HAART, a
significant increase in CD4 T-cell numbers was observed in both groups, but
there was no statistical difference regarding the response to HAART. This
study was reported in the journal AIDS Jan 3, 2003; 2003; 17(1):128-131.
The control group (younger patients) was matched by sex, year of HIV
diagnosis and the presence of AIDS-defining conditions. Fifty-eight older
patients (cases) were compared with 116 younger individuals (controls). Cases
had a median age of 57.5 years and controls 30.9. Seventy-six per cent of
subjects in both groups were men and 48% were in stage C (more advanced HIV)
of HIV infection. The mean of CD4 T cells was significantly lower in cases
(108 versus 187 cells), whereas the mean of the HIV viral load log was
similar in the two groups (4.97 versus 4.88), about 80,000 copies/ml. Cases
had more co-morbid conditions than controls (44.8 versus 15.5%).
One-third suffered from cardiovascular diseases, a rare condition among
controls. There was no statistically significant difference between cases and
controls observed in the type, number and duration of HAART regimens.
Immunological success (CD4 count) was observed in 69% of the cases and 79% of
the controls, no statistical difference between these two percentages.
Viral load response was about the same in younger and older patients.
Virological success was observed in 79% of cases and 72% of controls.
The following factors were associated with better responses to therapy:
Centers for Disease Control and Prevention (CDC) stage A (less advanced HIV
disease), having less co-morbid conditions, CD4 T-cell count at the beginning
and at 6, 12, 18, 24, 30 and 36 months of HAART, months to achieve CD4 T-cell
count greater than 200 cells, enhancement of CD4 T-cell count in the first 6
months, HIV viraemia at 30 months, dyslipidemia as an adverse effect of HAART.
Multivariate statistical analysis showed that after considering a number of
variables there was no statistically significant difference between the older
and younger patients.
Spanish researchers found similar results when looking at patients over 60
years of age. They compared the response to first-line HAART in patients aged
60 years or older and patients aged 40 years or less (AIDS
2001;15:1591-15930. The virological and immunological response to first-line
HAART containing two nucleoside analogues and a protease inhibitor was
prospectively evaluated in a cohort of 842 patients who initiated treatment
between 1997 and 1998 at Hospital del Mar, in Barcelona, Spain. After 24
months follow-up, findings in 28 (3.3% patients aged 60 years or older) were
compared with those in 671 patients aged 40 years or less. The viral load and
immunological (CD4) response to HAART after a 24 month follow-up was not
influenced by the patient's age. In fact 66% of the patients over 60 years of
age achieved <50 copies/ml viral load versus 50% in the younger patients, but
this difference was not statistically significant. CD4 counts increased by
228 in the patients over 60 (baseline CD4 count was 250) versus an increase
of 196 in the patients less than 40 years of age, and this difference in CD4
increase was not statistically different.
There was however a trend towards a more favourable clinical course in older
patients, which may be explained by a better adherence to the HAART regimen.
There was a high frequency of adverse events in older patients which may be
related to an age-related impairment of renal and liver function.
Self-reported lipodystrophy was found in 63% (14/22) of older patients
compared with 33% (180/541) in patients aged 40 years or less (P = 0.003,
odds ratio 3.5). The high rate of lipodystrophy may be a confounding factor
associated with the aging process. Age has been recognized as a risk factor
for developing the syndrome. The implications of lipodystrophy in older
patients may not be well understood.
Older folks with more co-morbid conditions may not respond as well to
therapy, as suggested by the results from the first study reported above, so
it might be preferable to treat older folks sooner in disease progression to
pre-empt the onset of co-morbid conditions.
A study conducted at Johns Hopkins and reported at Retrovirus Conference 2002
found that older folks over 50 years of age who were not treated with HAART
had more than double the risk of death than untreated younger patients (<50
years of age). These data suggest the benefit from HAART on survival is
greater in older than younger individuals and emphasize the importance of
treatment for older individuals. Both older and younger individuals who did
receive HIV treatment had the same 72% proportion surviving. This data
suggests deferring therapy in older folks may decrease survival more than
deferring therapy in younger patients. Testing older folks for HIV is
important: http://www.natap.org/2002/9retro/day15.htm
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