The EuroSIDA Study
To further assess a potential relationship between
anemia, immunologic damage during HIV infection, and clinical manifestations,
the EuroSIDA study was performed.[25] In this
survey of anemia prevalence, CD4 lymphocyte counts and hemoglobin levels were
available for 6725 patients at the time of recruitment. Approximately 40% of
patients were found to have normal hemoglobin levels, that is, greater than 14
g/dL for men and greater than 12 g/dL for women. A total of 1.4% of the patients
were found to have severe anemia, with a hemoglobin level less than 8 g/dL, and
the remaining 58.2% of the patients were found to have a mild anemia with values
between 8 g/dL and normal. At 12 months after enrollment, only 3% of those
patients with a normal hemoglobin level had died, compared with 16% with mild
anemia and 41% of the patients with an hemoglobin level less than 8 g/dL. The
same relationship with anemia was found after stratification for the absolute
number of CD4 cells, suggesting that the hemoglobin level is an independent
prognostic marker. The HIV viral load was also assessed in these patients. In
the adjusted analysis, a decrease in hemoglobin level of 1 g/dL increased the
relative hazard of dying by 1.57, which made this marker at least as important a
factor as the other two prognostic markers in evaluating the risk of death.
In Dr. Moore's experience at Hopkins, patients with a hemoglobin level less
than 10 g/dL had an almost 3-fold relative risk of dying compared with those
having higher hemoglobin levels. Again, this effect was seen as an independent
prognostic factor, independent of the CD4 cell count and viral load.[26] Thus, these observations do not prove causality
but suggest that anemia may be an independent prognostic factor for clinical
outcome in HIV patients.[26,27] What happens
when the hemoglobin levels improve in HIV patients? Are outcomes improved? In
the survey by Sullivan and colleagues, 32,000 HIV-infected patients were
compared, evaluating patients who had been treated for anemia vs those who had
not received a specific treatment.[25] Moore and
coworkers evaluated their database for similar outcomes,[24,28] and they found a similar outcome in patients
with clinical correction of their anemia and in patients who had never developed
anemia in the course of their HIV infection. Prospective trials are needed in
the future to better assess the impact of management of anemia in the AIDS
population and its impact on quality of life and treatment outcome.
