- The Change in Risk of Clinical Progression after Initiation of HAART: The EuroSIDA Study
Slide Session 1905
Authored by J.D. Lundgren, A. Mocroft, J.M. Gatell, O. Kirk, C. Katlama, S. Vella, A.N. Phillips
The EuroSIDA study is a long-term observational cohort that has been tracking the development of HIV/AIDS across Europe since the mid-90's. The scope of this study is enormous, canvassing over 20 European countries and involving over 8,500 patients. The study has been instrumental in assessing the impact of HAART on the HIV-infected population of Europe, and has produced countless publications and abstracts through the course of the study.
The latest accomplishment from this conglomerate, presented here, is a reproducible method for predicting clinical progression (AIDS or death) of HIV for patients on HAART. The investigators developed a scoring system based on four key prognostic markers: CD4 counts, hemoglobin (Hb) levels, viral load (VL), and AIDS status. The designated scoring system was formed based on the observation of 1847 patients in this particular cohort, and later applied successfully to two further cohorts.
Using Cox models, 4 measures were found to be independently related to risk for clinical progression following initiation of HAART. These were current CD4, hemoglobin, plasma viral load and AIDS status prior to HAART. Scoring for each patient was determined according to the following system:
(dependent upon Hb level)
|AIDS diagnosis prior to HAART?||No||0|
|Yes, but no PML/NHL||1|
|Yes, w/ PML/NHL||6|
Each risk factor is weighted according to its relative impact in contributing to clinical progression. It has long been known that anemia is a good prognostic indicator for disease progression, but it is interesting here that anemia is given such high point totals, with extreme anemia scoring even higher than prior AIDS diagnosis. This implies that hemoglobin levels are as important as CD4 and viral load counts in predicting disease progression.
The median score among the patients in this cohort at initiation of HAART was 4 (out of a possible 22). The investigators determined a score of less than 5 to be a low risk for clinical progression, a score of 5-9 to be a moderate risk, and a score of greater than or equal to 10 to be a high risk. At 12 months, the risk for clinical progression was 2%, 9% and 18% among these three respective risk categories. It was also observed that a 1 point scoring increase translated to a 31% increase in risk. 154 patients (8%) experienced clinical progression after HAART began.
The scoring system devised by these investigators may be a helpful patient management tool for clinicians, providing an aggregate measure for these four distinct factors. By enabling clinicians to reasonably predict the course of the disease, the scoring system will facilitate better, more targeted care.