- Anemia Prevalence Among HIV Patients: Antiretroviral Therapy and Other Risk Factors (Poster 1151)
Authored by J.P. Nadler, T.S. Wills, C. Somboonwit, A. Vincent, G. Leitz, K. Marino, E. Naik, S. Powers, N. Khan, N. Almyroudis, B. Laartz
Anemia is defined as a reduction below normal levels in the number of circulating red blood cells or the quantity of hemoglobin, an iron-containing protein within red blood cells. Since the earliest days of the epidemic, anemia has been recognized as an important clinical problem in HIV/AIDS. It was a very common occurrence associated with the use of the first antiretroviral agent AZT (zidovudine, Retrovir), and frequently seen in advanced stages of the disease. In the late 1980s and early 1990s, blood transfusions used to treat anemia in the setting of HIV disease were found to be associated with a significant increase in mortality in patients with AIDS, and recombinant human erythropoietin (epoetin alfa, Procrit) was approved as an alternative treatment option for anemia in HIV/AIDS patients treated with AZT.
Anemia adversely affects functional ability and quality of life. It can cause fatigue, shortness of breath, rapid heartbeat, exercise intolerance, headaches, inability to concentrate and other symptoms, ranging from mild to disabling. Anemia is also associated with decreased survival in HIV-positive individuals. The association between anemia and decreased survival has been found to be independent of CD4 cell count or HIV viral load. Anemic HIV-positive individuals who recover from anemia have better survival rates than those who do not recover.
Anemia Prevalence and HAART (Highly Active Antiretroviral Treatment)
The purpose of this study was to assess the effect of HAART on the prevalence of anemia in HIV-positive individuals. The introduction of HAART in 1996 had a profound impact on the clinical course of HIV disease, significantly slowing its progression and improving the long-term prognosis for many infected people. HIV-related anemia has been primarily characterized and studied in the pre-HAART era.
Initial data from the early HAART era indicated that severe anemia was less frequent, and anemia was subsequently perceived by many (both physicians and patients) to be less of a clinical issue. Additional studies suggested mild-to-moderate anemia continued to be common despite HAART. These more recent data, again collected during the HAART era, show that anemia continues to be associated with a worse prognosis, decreased survival time, increased risk of clinical progression and reduced quality of life. Consequently, the present study's primary objective was to determine the prevalence of anemia in HIV-positive patients seeking care within a single public health center (Hillsborough County Health Department, Florida, U.S.A.), and to evaluate the association of anemia with the use of HAART.
Methods and Results
The study included 758 patients (30.1 percent women and 69.9 percent men) with stable HIV disease, who were seen in the year 2000. Eighty-six percent were on HAART. The information collected, retrospectively, included demographic information, CD4 cell counts, viral loads, hemoglobin levels and HAART regimens. Patients with hemoglobin levels less than or equal to 12.5 g/dL were considered anemic.
The overall prevalence of anemia was 30.3 percent. The prevalence of anemia was higher in women (54 percent) than in men (20.2 percent). Anemia was also more prevalent in patients with lower CD4 cell counts and higher viral loads.
There was no significant difference in anemia prevalence (using the 12.5 g/dL definition) between patients receiving HAART and patients not receiving HAART. However, there was an increased prevalence of anemia in patients whose HAART regimen contained AZT. Detailed analysis of the variables identified that, in this study, the following were associated with a significantly increased risk of anemia:
Advanced HIV disease
Treatment with HAART regimens that contained AZT
This study found that mild-to-moderate anemia remains a common problem among HIV-positive patients receiving HAART.
HIV-related anemia can involve multiple causal mechanisms, and often several of these are operative in the same patient at the same time. These causal mechanisms include HIV itself, which can induce chronic inflammation and slow red blood cell production. In addition, drug toxicities, opportunistic infections, malabsorption syndromes leading to folate or vitamin B12 deficiency, blood loss, iron deficiency, lymphoma and other AIDS-related malignancies can all cause or contribute to anemia.
With the increased use of HAART, we have witnessed a decline in opportunistic infections, malignancies and infection-related malabsorption syndromes. Also, HAART may reduce levels of HIV chronic inflammation. All of these factors can improve anemia, and are most likely responsible for the decrease in cases of severe anemia noted during the HAART era. The present study indicates that in spite of these advances, mild-to-moderate anemia remains common. This information, in conjunction with previous studies suggesting that recovery from anemia is associated with improved survival and that treatment of mild-to-moderate anemia in HIV-positive patients enhances functional ability as well as improves quality of life, is important to both patients and treating physicians. Taken together, this information underscores the continuing importance of monitoring for anemia and maintaining normal hemoglobin levels as a treatment goal, even as antiretroviral therapies continue to improve.