Fifty per cent of HIV-positive patients taking highly active antiretroviral therapy (HAART) who are admitted to hospital had a CD4 cell count below 200 cells/mm3, according to a Scottish study published in theSeptember edition of HIV Medicine. Investigators also found that patients with a CD4 cell count below 200 cells/mm3 were more likely to have multiple admissions to hospital and to spend longer in hospital.
Hospital admissions amongst HIV-positive patients dropped dramatically following the introduction of HAART. Nevertheless, significant numbers of HIV-positive individuals still require treatment as in-patients, and this treatment is the most expensive element of HIV care.
Doctors from the Regional Infectious Disease Unit at the Western General Hospital in Edinburgh wished to examine the virological and immunological characteristics of HIV-positive individuals who had been taking HAART for at least six months, and were admitted to their unit between June 2002 and July 2003.
In a retrospective analysis, data were gathered on gender, age, HIV risk group, CD4 cell count, and viral load at the time of hospital admission.
Patients were divided into two exclusive groups depending on whether they had single or multiple admissions to hospital.
A total of 125 patients were included in the investigators’ analysis. Of these individuals, 50% had a CD4 cell count below 200 cells/mm3 despite taking at least six months of HAART.
Patients with a CD4 cell count below 200 cells/mm3 also accounted for 50% of multiple admissions (p 3 compared to a median of four per admission for individuals with higher CD4 cell counts (p
Despite taking HAART for at least six months, only 38% of patients with a CD4 cell count below 200 cells/mm3 had a viral load below 50 copies/ml.
Two-thirds of patients with a CD4 cell count below 200 cells/mm3 and an undetectable viral load had a history of injecting drug use and had an older median age (43 years) compared to patients in the rest of the study (40 years, p
There were high rates of hepatitis B virus (46%) and hepatitis C virus (50%) coinfection in the total study population. However, patients with hepatitis coinfection were no more likely to be admitted to hospital more than once.
“This study showed that 50% of patients on HAART for at least six months who were admitted to hospital were immunosuppressed. Immunosuppression was significantly more common amongst patients with multiple admissions,” write the investigators.
The investigators explore several possible reasons for immune suppression despite six months of HAART, including poor adherence and resistance.
However, they also note slow immune recovery could account for immunosuppression in many patients, and they comment, “having CD4 cell counts of below 200 cells/mm3 despite undetectable viraemia for at least six months accounted for 21% of admissions.”
Poor immune reconstitution despite successful suppression of viral load has previously been observed in patients who start HAART when their CD4 cell count is below 350 cells/mm3 and amongst injecting drug users, note the investigators.
Given their findings that immunosuppressed patients have more admissions to hospital and spend longer in hospital per admission, the investigators suggest “earlier initiation of HAART for older patients and the use of interleukin-2 may be beneficial.”
Manavi K et al. A significant proportion of HIBV-infected patients admitted to hospital have immunosuppression as a result of the failure of highly active antiretroviral therapy. HIV Med 5: 360-363, 2004.