The influence of drug use and apolipoprotein E on HIV related disease of the central nervous system

• Main Author: Arango-Viana, Juan Carlos
• Published: University of Edinburgh 2002
• Subjects: 610.21
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.640569

Aims: i) To determine the contribution of host factors such as drug use (DU) and apolipoprotein E (ApoE) genotype in the development of HIVE and HAD. ii) To investigate some histological changes relevant to HAD in drug users with different ApoE genotypes. Methods: Genotyping for ApoE was carried out in 312 individuals who were divided into five groups. Group I consisted of 64 normal controls, Group II consisted of 82 HIV negative drug users, Group III consisted of 38 presymptomatic HIV positive drug users (pre AIDS), Group IV consisted of 84 drug users with AIDS, Group V consisted of non drug users with AIDS (6 haemophiliacs and 38 men who have sex with men (MSM). Results: Analyses showed that the frequency of ApoE <i>e2</i> allele in the HIV positive drug users (Groups III and IV taken together, n=122) was 14.3%. In contrast, the frequency for the ApoE <i>e2</i> in groups I (n=64) and II (n=82) was 5.4% in each group and 8.2% in normal Scottish population (group VI, n=400). These differences were significant (X²=7.017, p<0.008, and X²=7.580, p<0.006, respectively). At the same time, the ApoE <i>e3</i> allele for groups III and IV was found to be under represented when compared to the Scottish population (X²=9.695, p<0.0002). More detailed comparisons between different genotype subsets within the groups all gave results supportive of the main finding of ApoE <i>e2</i> over representation. Group V showed no difference in ApoE genotype from the general population. CD4 and CD8 counts were found to be significantly higher in group IV compared with Group V. 53.9% Group IV individuals had CD4 counts above 50^th percentile, in contrast to only 21.5% in individuals in group V (X²= 11.242, p<0.001). For CD8, 48.8% of the group IV cases had counts above the 50^th percentile, while only 23.1% of group V were above (X²=8.740, p<0.003). The ApoE <i>e³ </i>allele was found negatively associated with CD8 counts (X²=5.063, p<0.02), but the positive association of ApoE e2 allele with CD8 counts did not reach significance (X²=3.593, p<0.058). The histological change which was most strongly associated with dementia was HIVE (X²=14.977, p<0.0005). The association of ApoE alleles with HIVE showed that ApoE e2 and e3 alleles were significantly with HIVE (X²= 4.007, p<0.05 and X²=5.090, p<0.02 respectively), although the direction of the association with the ApoE e3 allele was negative.