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Objectives: We sought to evaluate associations between CD4 at ART initiation (AI), achieving CD4 >750 cells/mm(3) (CD4 >750), long-term immunological recovery and survival., Methods: This was a prospective observational cohort study. We analysed data from ART-naive patients seen in 1996-2012 and followed ≥3 years after AI. We used Kaplan-Meier (KM) methods and log-rank tests to compare time to achieving CD4 >750 by CD4 at AI (CD4-AI); and Cox regression models and generalized estimating equations to identify factors associated with achieving CD4 >750 and mortality risk., Results: Of 1327 patients, followed for a median of 7.9 years, >85% received ART for ≥75% of follow-up time; 64 died. KM estimates evaluating likelihood of CD4 >750 during 5 years of follow-up, stratified by CD4-AI <50, 50-199, 200-349, 350-499 and 500-750, were 20%, 25%, 56%, 80% and 87%, respectively (log-rank P < 0.001). In adjusted models, CD4-AI ≥200 (versus CD4-AI <200) was associated with achievement of CD4 >750 [adjusted HR (aHR) = 4.77]. Blacks were less likely than whites to achieve CD4 >750 (33% versus 49%, aHR = 0.77). Mortality rates decreased with increasing CD4-AI (P = 0.004 across CD4 strata for AIDS causes and P = 0.009 for non-AIDS death causes). Among decedents with CD4-AI ≥50, 56% of deaths were due to non-AIDS causes., Conclusions: Higher CD4-AI resulted in greater long-term CD4 gains, likelihood of achieving CD4 >750, longer survival and decreased mortality regardless of cause. Over 80% of persons with CD4-AI ≥350 achieved CD4 >750 by 4 years while 75% of persons with CD4-AI <200 did not. These data confirm the hazards of delayed AI and support early AI., (© The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Objective: The aim of the study was to describe longitudinal changes in serum lipids among HIV-infected men receiving highly active antiretroviral therapy (HAART) with long-term follow-up., Methods: A total of 304 HIV-infected men who initiated HAART and who had serum lipid measurements prior to and for up to 7 years after HAART initiation were identified from the Multicenter AIDS Cohort Study (MACS). Mean levels of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) were examined at biannual time-points., Results: Significant lipid changes were seen within 0.5 years of HAART initiation but increases in TC (+1.09 mmol/L), LDL-C (+0.57 mmol/L), HDL-C (+0.16 mmol/L) and non-HDL-C (+0.91 mmol/L) reached peak levels 2-3 years after HAART initiation. Declines in serum TC, LDL-C and non-HDL-C in subsequent years occurred concurrently with a substantial increase in use of lipid-lowering medications (from 1% usage pre-HAART to 43% 6-7 years after HAART initiation) but the proportion of men who either were treated with cholesterol-lowering medication or had elevated cholesterol levels (>5.18 mmol/L) did not change during the 2-7-year interval after HAART. Mean HDL-C also decreased after 2-3 years and was low (<1.04 mmol/L) in 55% of HIV-infected men 6-7 years after HAART initiation., Conclusions: Atherogenic serum lipids increased early after the initiation of HAART, peaked at 2-3 years and remained high or required treatment thereafter. Low HDL-C levels persisted in the majority of men. The long-term effects of lipid abnormalities on cardiovascular risk and the effectiveness and toxicity of prolonged use of lipid-lowering medications in combination with HAART are not known.

Objective: To determine whether ejaculate exposure through anoreceptive intercourse is associated with rapid CD4 cell loss., Design: Self-reported behavioral, demographic data and blood samples were gathered longitudinally at ten semiannual visits from individuals participating in the Multicenter AIDS Cohort Study (MACS)., Patients/participants: A group of 937 HIV-seropositive men who were continuously followed for four to ten semiannual visits., Outcome Measures: A loss of 10% or more in CD4 cells between the first two of any three consecutive semiannual visits that was followed by a 10% or greater loss between the second and third visits., Results: A period of rapid CD4 cell loss over three semiannual visits occurred in 389 of the 937 (42%) HIV-seropositive men studied. Men who reported one or more anoreceptive intercourse partners with whom they were exposed to ejaculate (RAI-E) during the 12 months immediately preceding their visits were more than twice as likely to show this rapid CD4 cell loss compared with men with no such partners., Conclusions: The association between RAI-E partnerships and rapid CD4 cell loss suggests factors associated with ejaculate exposure (e.g., sexually transmitted diseases) may hasten the clinical progression of HIV disease. It is suggested that infectious diseases, which are known to be associated with ejaculate exposure, may be the causal factor underlying the association between RAI-E partnerships and rapid CD4 cell loss in these men, although the presence of these diseases was not ascertained in these data. HIV-infected individuals should be cautioned against unprotected anoreceptive intercourse.

To examine the effect of HIV status, symptomatology and CD4+ lymphocyte level on health-related quality of life, the Medical Outcomes Study Short-Form Health Survey (SF-36) was administered to 2,295 gay men enrolled in the Multicenter AIDS Cohort Study (MACS) in 1994. Distinct physical and mental health factors of the SF-36 were found. Seropositive asymptomatic individuals and seropositive individuals with CD4+ lymphocytes > or = 500/mm3 scored as well as seronegative participants on all of the mental health domain scales, but lower on the general health perceptions and physical health composite score. Seropositive individuals with at least one symptom or with CD4+ lymphocytes below 200/mm3 scored significantly lower on all of the SF-36 scales and summary scores than seronegative controls. The SF-36 was found to exhibit similar mental and physical health factors for an adult gay male population to that previously seen in general population samples and in patient groups with other diseases. In conclusion, HIV-positive men who are asymptomatic or have CD4+ lymphocytes above 500/mm3 have similar perceived mental health but worse perceived physical health than seronegative men. HIV-positive men who are symptomatic or have CD4+ lymphocytes below 200/mm3 have worse perceived mental and physical health than seronegative men.

A homozygous 32-bp deletion in the gene encoding CCR5, a major coreceptor for HIV-1, leads to resistance to infection with HIV-1, and heterozygosity for the deletion is associated with delayed disease progression in persons infected with HIV-1. We investigated the effect of CCR5 heterozygosity on disease progression as measured by both CD4+ T-cell count decline and the occurrence of clinical AIDS symptoms. Using a unified statistical model for CD4 count progression and AIDS development, we examined whether the effect of CCR5 heterozygosity on clinical AIDS is direct or indirect through its effect on CD4 counts. Based on data from the Multicenter AIDS Cohort Study, we noted a protective effect of CCR5 heterozygosity on both CD4 cell count progression and on AIDS occurrence. Furthermore, we found that this protective effect on the occurrence of AIDS was completely mediated through an effect on the CD4 marker. Additional adjustment for the effect of an initial viral load measurement indicate that CCR5 heterozygosity did not have predictive value for either CD4 progression or the development of AIDS beyond its association with early viral load.

Objective: To determine whether race is associated with health insurance coverage and health service use among gay and bisexual men in the Baltimore center of the Multicenter AIDS Cohort Study., Methods: Data from eight semiannual study visits between 1991 and 1996 were used. Descriptive, stratified, and logistic regression analyses were conducted to determine whether race is associated with insurance coverage, medical, or dental service use, after controlling for socioeconomic variables., Results: No difference was found between blacks' and whites' likelihood of having health insurance, private insurance, using inpatient, emergency department services, or antiretroviral medications. Whites were more likely to use outpatient services, particularly if CD4 cell counts were high, and were more likely to use dental services, although blacks were more likely to have dental insurance., Conclusions: Further research must be conducted to examine cultural, social, and psychological factors that help explain why white gay men use more outpatient and dental services, when other service use is unrelated to race. Investigators should be precise when using race as a variable in health services and epidemiologic research, emphasizing when racial differences truly exist versus when the variable race is a surrogate for another factor.

Studies of circulating T (CD3(+)) lymphocytes have shown that on a population basis T-cell numbers remain stable for many years after HIV-1 infection (blind T-cell homeostasis), but decline rapidly beginning approximately 1.5-2.5 years before the onset of clinical AIDS. We derived a general method for defining the loss of homeostasis on the individual level and for determining the prevalence of homeostasis loss according to HIV status and the occurrence of AIDS in more than 5,000 men enrolled in the Multicenter AIDS Cohort Study. We used a segmented regression model for log10 CD3(+) cell counts that included separate T-cell trajectories before and after a time (the T-cell inflection point) where the loss of T-cell homeostasis was most likely to have occurred. The average slope of CD3(+) lymphocyte counts before the inflection point was close to zero for HIV- and HIV+ men, consistent with blind T-cell homeostasis. After the inflection point, the HIV+ individuals who developed AIDS generally showed a dramatic decline in CD3(+) cell counts relative to HIV- men and HIV+ men not developing AIDS. A CD3(+) cell decline of greater than 10 percent per year was present in 77% of HIV+ men developing AIDS but in only 23% of HIV+ men with no onset of AIDS. Our findings at the individual level support the blind T-cell homeostasis hypothesis and provide strong evidence that the loss of homeostasis is an important mechanism in the pathogenesis of the severe immunodeficiency that characterizes the late stages of HIV infection.

Objective: To determine whether racial differences exist in the rate of CD4 lymphocyte decline in HIV-1-infected homosexual men., Design: Prospective cohort study., Study Population: Non-Hispanic white (n = 321) and black (n = 102) HIV-1-seropositive homosexual and bisexual men were recruited from the Baltimore/Washington, DC metropolitan areas between 1984-1985 and 1987-1990, and evaluated semiannually., Main Measurements: Changes in CD4 lymphocyte count and CD4 percentage over time were analysed using linear regression methods for the 271 white and 69 black participants who had at least four semiannual CD4 lymphocyte measurements., Results: Rate of decline in CD4 lymphocyte count over 6 months was much slower among black than white seroprevalent men at all levels of baseline CD4 count (baseline 201-400 x 10(6)/l: + 0.24 versus -17.7 x 10(6)/l; 401-600 x 10(6)/l: -11.3 versus -23.9 x 10(6)/l; 601-800 x 10(6)/l: -15.1 versus -35.2 x 10(6)/l; > 800 x 10(6)/l: -4.3 versus -42.7 x 10(6)/l for black versus white, respectively), although this was only statistically significant for the lowest and highest strata of baseline CD4 count. These racial differences persisted after adjustment for recruitment period (1984-1985 or 1987-1990), follow-up duration, age and zidovudine therapy or Pneumocystis carinii pneumonia prophylaxis. Similar findings were observed among the 70 white and 11 black seroconverters. Black participants were also less likely than a subgroup of white participants matched on baseline CD4 lymphocyte count to be HIV-1 p24 antigen-positive. However, after acid dissociation of samples initially p24 antigen-negative, there were no significant differences in the prevalence of p24 antigenemia at enrollment or after 1 year of follow-up., Conclusions: This analysis suggests a more gradual decline in CD4 lymphocyte count among black than white Americans. The clinical significance of and reasons for this are unclear, but the lower prevalence of p24 antigenemia due to immune complexing among black Americans suggests that racial differences in the immune response to HIV may exist. Additional studies are needed to validate these findings in a larger cohort of non-whites, and to assess their relationship with other measures of cell-mediated immune function.

Objective: To estimate expected survival time among homosexual men infected with the human immunodeficiency virus type 1 (HIV-1) by (1) the calendar period before (1985-1988) and after (1989-1993) the widespread availability of acquired immunodeficiency syndrome (AIDS) treatments with antiretroviral and prophylactic interventions, and (2) stage of HIV disease., Design: A prospective cohort study. A group of HIV-1-infected homosexual men were followed from July 1985 through June 1993 and evaluated every 6 months for the presence of clinical symptoms and measurement of the CD4 cell count. To measure the effectiveness of AIDS therapies in this nonrandomized study, we used 2 calendar periods as proxy measures of relative intensity of exposure to antiretroviral therapy. Stage of infection was defined by CD4 cell count and presence of HIV-related clinical symptoms or AIDS., Setting and Study Participants: Homosexual men infected with HIV-1 from the Multicenter AIDS Cohort Study., Main Outcome Measure: Survival time based on stage of HIV infection., Results: The percentage of HIV-1-infected individuals free of AIDS and clinical symptoms at baseline who survived 2.5 years according to baseline CD4 cell counts of 0 to 0.100, 0.101 to 0.200, and 0.201 to 0.350 x 10(9)/L was 22%, 53%, and 83%, respectively, for the 1985-1988 calendar period, compared with 54%, 71%, and 91%, respectively, for men in the 1989-1993 calendar period. Among men free of AIDS with CD4 cell counts of greater than 0.350 x 10(9)/L, the relative hazard of mortality was 1.6 to 2.3 times higher for those with clinical symptoms compared with those free of clinical symptoms., Conclusions: Survival of AIDS-free HIV-1-infected individuals with CD4 cell counts of less than 0.350 x 10(9)/L has improved since antiretroviral and HIV prophylactic treatments have become available, but the long-term prognosis remains poor.

Methods are developed to estimate and test for the impact of intervention use on a population's survival function (time to AIDS). Each participant's history is divided into J + 1 components: omega 0 occurring before the intervention is available and omega 1 to omega J occurring later, as the intervention becomes successively more available. Distribution free truncated Kaplan-Meier models based on time since exposure fit separately to the risk sets/outcomes in omega 0 to omega J directly show the changing patterns of survival. Multivariate proportional hazards models can be used to adjust for covariates. Application of these methods indicates that availability of proven anti-AIDS interventions may have delayed time to AIDS by 8 months in an educated HIV-1 infected homosexual cohort with good access to medical care.

The purpose of this study was to characterize the epidemiologic, clinical, and laboratory parameters of a cohort of men at risk of AIDS-associated toxoplasmic encephalitis. One hundred seventeen (11%) of the 1,073 participants at the time of enrollment into the Chicago Multicenter AIDS Cohort Study (MACS) were seropositive for Toxoplasma antibodies. Significant differences in prevalence of antibodies between African-American, Hispanic, or white men were not observed (p = 0.49). One hundred one (86%) of the 117 antibody-positive participants had at least one follow-up serology performed and 6 (6%) of the 101 had a significant rise in IgG antibody titer on subsequent visits. Five of six participants with a significant rise in titer were also seropositive for HIV-1 at entry or seroconverted during the study. A trend toward higher IgG Toxoplasma titers and prevalence of IgM antibodies in participants seropositive for HIV-1 was observed, but the differences did not reach statistical significance. There was no evidence that the presence of Toxoplasma infection predisposed to development of CD4+ depletion or AIDS. None of the 183 individuals in the cohort who developed AIDS and who were seronegative for Toxoplasma antibodies developed toxoplasmic encephalitis. In contrast, of the 13 persons who developed AIDS and who were positive for Toxoplasma antibodies, 5 (38%) developed toxoplasmic encephalitis. Prevalence of Toxoplasma antibodies in the MACS population was independent of HIV-1 serostatus. Toxoplasma infection does not appear to predispose to progression of HIV-1 infection. The risk of development of toxoplasmic encephalitis in persons with AIDS and chronic Toxoplasma infection may have been underestimated by previous retrospective studies.

Serum antibody to p24 (anti-p24) and p24 antigen, alone and in combination with CD4+ lymphocyte number, were evaluated as predictors of progression of human immunodeficiency virus type 1 (HIV-1) infection. Two hundred six HIV-1-prevalent seropositive men in the Multi-center AIDS Cohort Study since 1984-1985 were studied cross-sectionally and 84 seroconverters were evaluated longitudinally. Cross-sectional analyses revealed significant associations among titer of anti-p24, CD4+ cell count, disease status (Centers for Disease Control class), and progression to AIDS. A high titer of anti-p24 was associated with lack of p24 antigenemia. Longitudinal studies of seroconverters demonstrated that a low titer of anti-p24, low CD4+ cell count, and detection of HIV-1 p24 antigen are individually strong predictors of AIDS, but only low CD4+ cell count retains its independent predictive value in multivariate analysis of the three markers during the period immediately after infection with HIV-1.

Previous research has demonstrated isolated effects of host genetic factors on the progression of human immunodeficiency virus type 1 (HIV-1) infection. In this paper, the authors present a novel use of multivariable methods for estimating the prevented fraction of acquired immunodeficiency syndrome (AIDS) cases attributable to six restriction genes after accounting for their epidemiologic interactions. The methods presented will never yield a prevented fraction above 1. The study population consisted of a well-characterized cohort of 525 US men with HIV-1 seroconversion documented during follow-up (1984–1996). On the basis of a regression tree approach using a Cox proportional hazards model for times to clinical AIDS, the combinations of genes associated with the greatest protection, relative to the lack of a protective genotype, consisted of: 1) C-C chemokine receptor 5 (CCR5)-Δ32and C-C chemokine receptor 2 (CCR2)-64I (relative hazard = 0.44); 2) interleukin 10 (IL10)-+/+ in combination with CCR5-Δ32orCCR2-64I (relative hazard = 0.45); and 3) IL10-+/+ in combination with stromal-derived factor (SDF1)-3 ′A and CCR5 promoter P1/~P1 (relative hazard = 0.37). Overall, 30% of potential AIDS cases were prevented by the observed combinations of restriction genes (95% confidence interval: 7, 47). However, the combined effect was confined to the first 4 years following HIV-1 seroconversion. Additional research is needed to identify AIDS restriction genes with stronger and long-lasting protection to better characterize the genetic epidemiology of HIV-1. [ABSTRACT FROM AUTHOR]