Vincent C. Marconi

Trends in the Incidence of Cancers among HIV-Infected Persons and the Impact of Antiretroviral Therapy: A 20-Year Cohort Study

Objective:To describe trends in incidence rates of AIDS-defining cancers (ADCs) and non-AIDS-defining cancers (NADCs) during the HIV epidemic and to evaluate predictors, including the impact of antiretroviral therapy, of cancer development. Design:Retrospective analysis of a multicenter, prospective natural history study including 4498 HIV-infected US military beneficiaries with 33 486 person-years of follow-up. Methods:Predictors evaluated included demographics, clinical data, time-updated CD4 cell counts, HIV viral loads, and antiretroviral history. Time periods were classified as early pre (1984–1990), late pre (1991–1995), early post (1996–2000), and late post (2001–2006) HAART eras. Cox proportional hazard models were used to evaluate the association of specific factors with cancer. Results:Ten percent of HIV-infected persons developed cancer. ADC rates increased between the early and late pre-HAART eras (7.6 and 14.2 cases per 1000 person-years) and have since declined from 5.4 to 2.7 in the early and late HAART eras, respectively (P < 0.001). Rates of NADCs have risen over the four periods (2.9, 2.8, 4.2, 6.7, P = 0.0004). During the late HAART era, 71% of cancers were NADCs. Predictors for ADCs included low CD4 cell count, noncancer AIDS diagnosis, and lack of HAART. NADCs were predicted by increasing age and white race (due to skin cancers). Conclusion:Although the rate of ADCs continues to fall, the rate of NADCs is rising and now accounts for the majority of cancers in HIV-infected persons. The development of NADCs is associated with increasing age among HIV patients. HAART use is protective for ADCs, but did not significantly impact NADCs.

Clinical Outcomes of Elite Controllers, Viremic Controllers, and Long-Term Nonprogressors in the US Department of Defense HIV Natural History Study

Durable control of human immunodeficiency virus (HIV) replication and lack of disease progression in the absence of antiretroviral therapy were studied in a military cohort of 4586 subjects. We examined groups of elite controllers (ie, subjects with plasma HIV RNA levels of <50 copies/mL; prevalence, 0.55% [95% confidence interval {CI}, 0.35%-0.80%]), viremic controllers (ie, subjects with plasma HIV RNA levels of 50-2000 copies/mL; prevalence, 3.34% [95% CI, 2.83%-3.91%]), and subjects with a lack of disease progression (ie, long-term nonprogressors [LTNPs]) through 7 years of follow-up (LTNP7s; prevalence, 3.32% [95% CI, 2.70%-4.01%]) or 10 years of follow-up (LTNP10s; prevalence, 2.04% [95% CI, 1.52%-2.68%]). For elite and viremic controllers, spontaneous virologic control was established early and was typically observed when the initial viral load measurement was obtained within 1 year of estimated seroconversion. Elite controllers had favorable time to development of AIDS (P=.048), a CD4 cell count of 350 cells/microL (P= .009), and more-stable CD4 cell trends, compared with viremic controllers. LTNPs defined by 10-year versus 7-year criteria had a longer survival time (P=.001), even after adjustment for differing periods of invulnerability (P= .042). Definitions of controllers and LTNPs describe distinct populations whose differing clinical outcomes improve with the stringency of criteria, underscoring the need for comparability between study populations.

Duffy Antigen Receptor for Chemokines Mediates trans-Infection of HIV-1 from Red Blood Cells to Target Cells and Affects HIV-AIDS Susceptibility

Duffy antigen receptor for chemokines (DARC) expressed on red blood cells (RBCs) influences plasma levels of HIV-1-suppressive and proinflammatory chemokines such as CCL5/RANTES. DARC is also the RBC receptor for Plasmodium vivax. Africans with DARC -46C/C genotype, which confers a DARC-negative phenotype, are resistant to vivax malaria. Here, we show that HIV-1 attaches to RBCs via DARC, effecting trans-infection of target cells. In African Americans, DARC -46C/C is associated with 40% increase in the odds of acquiring HIV-1. If extrapolated to Africans, approximately 11% of the HIV-1 burden in Africa may be linked to this genotype. After infection occurs, however, DARC-negative RBC status is associated with slower disease progression. Furthermore, the disease-accelerating effect of a previously described CCL5 polymorphism is evident only in DARC-expressing and not in DARC-negative HIV-infected individuals. Thus, DARC influences HIV/AIDS susceptibility by mediating trans-infection of HIV-1 and by affecting both chemokine-HIV interactions and chemokine-driven inflammation.

Anal Cancers among HIV-Infected Persons: HAART Is Not Slowing Rising Incidence

Objective:To evaluate the incidence rates of anal cancer over the HIV epidemic and assess the impact of HAART use on anal cancer events. Methods:We evaluated the incidence of and factors associated with anal cancer using longitudinal data from the prospective U.S. Military Natural History Study (1985–2008). Poisson regression and Cox proportional hazard models were utilized. Results:Among 4506 HIV-infected men with 37 806 person-years of follow-up, anal cancer rates (per 100 000 person-years) increased five-fold, from 11 in the pre-HAART to 55 in the HAART era (P = 0.02). Rates continued to increase, reaching 128 in 2006–2008. Persons with HIV infection for more than 15 years had a 12-fold higher rate than those with less than 5 years (348 vs. 28, P < 0.01). At cancer diagnosis (n = 19), median age was 42 years, median CD4 cell count was 432 cells/μl, 74% had a CD4 nadir cell count less than 200 cells/μl, 42% had a prior AIDS event, and 74% had received HAART. From separate models, prior AIDS event (hazard ratio 3.88, P = 0.01) and lower CD4 nadir (hazard ratio 0.85 per 50 cell, P = 0.03) were associated with anal cancer, with a trend for a history of gonorrhea (hazard ratio 2.43, P = 0.07). Duration of HAART use was not associated with a reduced risk of anal cancer (hazard ratio 0.94, P = 0.42). Conclusion:Incidence rates of anal cancer have progressively increased during the HIV epidemic. Persons with a longer duration of HIV infection have a substantially higher rate of anal cancer. As HIV-infected persons are experiencing longer life expectancies and HAART does not appear protective of anal cancer, studies on preventive strategies are needed.

Apolipoprotein (apo) E4 enhances HIV-1 cell entry in vitro, and the APOE ε4/ε4 genotype accelerates HIV disease progression

Originally recognized for their role in lipoprotein metabolism and cardiovascular disease, apolipoprotein (apo) E isoforms (apoE2, apoE3, and apoE4) have also been implicated to play a key role in several biological processes not directly related to their lipid transport function. For example, apoE4 contributes significantly to neurodegeneration in Alzheimers disease. However, the role of apoE in infectious diseases is less well defined. Here, by examining a large cohort of HIV+ European and African American subjects, we found that the APOE ε4/ε4 genotype is associated with an accelerated disease course and especially progression to death compared with the APOE ε3/ε3 genotype. However, an association between the ε4/ε4 genotype and HIV-associated dementia (HAD), a neurological condition with clinicopathological features similar to Alzheimers disease, was not detected. Consistent with the genotype–phenotype relationships observed, compared with recombinant apoE3, apoE4 enhanced HIV fusion/cell entry of both R5 and X4 HIV strains in vitro. These findings establish apoE as a determinant of HIV-AIDS pathogenesis and raise the possibility that current efforts to convert apoE4 to an “apoE3-like” molecule to treat Alzheimers disease might also have clinical applicability in HIV disease.

CCL3L1-CCR5 genotype influences durability of immune recovery during antiretroviral therapy of HIV-1-infected individuals

The basis for the extensive variability seen in the reconstitution of CD4+ T cell counts in HIV-infected individuals receiving highly active antiretroviral therapy (HAART) is not fully known. Here, we show that variations in CCL3L1 gene dose and CCR5 genotype, but not major histocompatibility complex HLA alleles, influence immune reconstitution, especially when HAART is initiated at <350 CD4+ T cells/mm3. The CCL3L1-CCR5 genotypes favoring CD4+ T cell recovery are similar to those that blunted CD4+ T cell depletion during the time before HAART became available (pre-HAART era), suggesting that a common CCL3L1-CCR5 genetic pathway regulates the balance between pathogenic and reparative processes from early in the disease course. Hence, CCL3L1-CCR5 variations influence HIV pathogenesis even in the presence of HAART and, therefore, may prospectively identify subjects in whom earlier initiation of therapy is more likely to mitigate immunologic failure despite viral suppression by HAART. Furthermore, as reconstitution of CD4+ cells during HAART is more sensitive to CCL3L1 dose than to CCR5 genotypes, CCL3L1 analogs might be efficacious in supporting immunological reconstitution.

Increasing Rates of Obesity among HIV-Infected Persons during the HIV Epidemic

Background The prevalence and factors associated with overweight/obesity among human immunodeficiency virus (HIV)-infected persons are unknown. Methods We evaluated prospective data from a U.S. Military HIV Natural History Study (1985–2004) consisting of early diagnosed patients. Statistics included multivariate linear regression and longitudinal linear mixed effects models. Results Of 1682 patients, 2% were underweight, 37% were overweight, and 9% were obese at HIV diagnosis. Multivariate predictors of a higher body mass index (BMI) at diagnosis included more recent year of HIV diagnosis, older age, African American race, and earlier HIV stage (all p<0.05). The majority of patients (62%) gained weight during HIV infection. Multivariate factors associated with a greater increase in BMI during HIV infection included more recent year of diagnosis, lower BMI at diagnosis, higher CD4 count, lower HIV RNA level, lack of AIDS diagnosis, and longer HIV duration (all p<0.05). Nucleoside agents were associated with less weight gain; other drug classes had no significant impact on weight change in the HAART era. Conclusions HIV-infected patients are increasingly overweight/obese at diagnosis and during HIV infection. Weight gain appears to reflect improved health status and mirror trends in the general population. Weight management programs may be important components of HIV care.

HIV-1 Disease-Influencing Effects Associated with ZNRD1, HCP5 and HLA-C Alleles Are Attributable Mainly to Either HLA-A10 or HLA-B*57 Alleles

A recent genome-wide association study (GWAS) suggested that polymorphisms in or around the genes HCP5, HLA-C and ZNRD1 confer restriction against HIV-1 viral replication or disease progression. Here, we also find that these alleles are associated with different aspects of HIV disease, albeit mainly in European Americans. Additionally, we offer that because the GWAS cohort was a subset of HIV-positive individuals, selected based in part on having a low viral load, the observed associations for viral load are magnified compared with those we detect in a large well-characterized prospective natural history cohort of HIV-1-infected persons. We also find that because of linkage disequilibrium (LD) patterns, the dominant viral load- and disease-influencing associations for the ZNRD1 or HLA-C and HCP5 alleles are apparent mainly when these alleles are present in HLA-A10- or HLA-B*57-containing haplotypes, respectively. ZNRD1 alleles lacking HLA-A10 did not confer disease protection whereas ZNRD1-A10 haplotypes did. When examined in isolation, the HCP5-G allele associates with a slow disease course and lower viral loads. However, in multivariate models, after partitioning out the protective effects of B*57, the HCP5-G allele associates with disease-acceleration and enhanced viral replication; these associations for HCP5-G are otherwise obscured because of the very strong LD between this allele and a subset of protective B*57 alleles. Furthermore, HCP5 and HLA-C alleles stratify B*57-containing genotypes into those that associate with either striking disease retardation or progressive disease, providing one explanation for the long-standing conundrum of why some HLA-B*57-carrying individuals are long-term non-progressors, whereas others exhibit progressive disease. Collectively, these data generally underscore the strong dependence of genotype-phenotype relationships upon cohort design, phenotype selection, LD patterns and populations studied. They specifically demonstrate that the influence of ZNRD1 alleles on disease progression rates are attributable to HLA-A10, help clarify the relationship between the HCP5, HLA-C and HLA-B*57 alleles, and reaffirm a critical role of HLA-B*57 alleles in HIV disease. Furthermore, as the protective B*57-containing genotypes convey striking salutary effects independent of their strong impact on viral control, it is conceivable that T cell-based therapeutic vaccine strategies aimed at reducing viral loads may be inadequate for limiting AIDS progression, raising the potential need for complementary strategies that target viral load-independent determinants of pathogenesis.

Virologic response differences between african americans and european americans initiating highly active antiretroviral therapy with equal access to care

Objective:Studies comparing virologic response to highly active antiretroviral therapy (HAART) between African Americans (AA) and European Americans (EA) have been confounded by differences in duration of HIV infection and access to health care. We evaluated virologic response to HAART between ethnicities in a large cohort with fewer confounders. Methods:The odds of attaining viral suppression at 6- and 12-months post-HAART were determined by multivariate logistic regression for HIV-infected AA and EA prospectively followed in a large US military cohort. Time-to-event methods were used to compare maintenance of suppression. Results:A total of 1363 subjects (51% AA, 92% men) with viral load results available 6 months after HAART initiation were included. There was no difference between ethnicities in time from seroconversion to HIV diagnosis or HAART initiation or in HAART regimens. Adjusted for multiple demographic and HIV-related factors, AA had significantly lower odds of obtaining undetectable viral loads after 6 (odds ratio 0.6, 95% confidence interval 0.4-0.8, P < 0.001) and 12 months (odds ratio 0.6, 95% confidence interval 0.4-0.8, P = 0.002) of HAART. Once undetectable, there was no difference in time to virologic failure between AA and EA. Conclusions:Despite similar durations of HIV infection and equal access to health care, AAs were significantly less likely to achieve viral suppression compared with EA.

Increasing Age at Hiv Seroconversion From 18 to 40 Years Is Associated With Favorable Virologic and Immunologic Responses to Haart

Background:Studies evaluating the effect of age on response to highly active antiretroviral therapy (HAART) have been limited by their inability to control for duration of human immunodeficiency virus (HIV) infection. We examined the effect of age at HIV seroconversion on response to HAART. Methods:A retrospective analysis of a longitudinal US military cohort of HIV-infected subjects. Time to and maintenance of viral suppression, rate of CD4 cell increase, and rate of progression to acquired immunodeficiency syndrome or death were compared across age groups using time-to-event methods. Results:Five hundred sixty-three HIV-infected adults who seroconverted after January 1, 1996, and started HAART were included. Increasing age at seroconversion was significantly associated with faster time to viral suppression (P = 0.002). Increasing age also correlated with duration of suppression, with a 35% reduction in risk of viral rebound for every 5-year increase in age above 18 years (hazard ratio: 0.65, 95% confidence interval 0.55 to 0.75). The rate of CD4 cell increase from 6 to 84 months post-HAART was significantly greater in those who seroconverted at older ages (P = 0.0002). Rates of progression to acquired immunodeficiency syndrome or death did not differ between groups. Conclusions:Increasing age at seroconversion was associated with shorter time to and longer maintenance of viral suppression and a faster increase in CD4 cell count.