Differences in time from HIV seroconversion to CD4+ lymphocyte end-points and AIDS in cohorts of homosexual men

Time from human immunodeficiency virus seroconversion to reaching CD4+ cell count thresholds <200, <350, and <500 Cells/mm³: assessment of need following changes in treatment guidelines

BACKGROUND

Recent updates of human immunodeficiency virus (HIV) treatment guidelines have raised the CD4+ cell count thresholds for antiretroviral therapy initiation from 350 to 500 cells/mm(3) in the United States and from 200 to 350 cells/mm³ in mid- and low-income countries. Robust data of time from HIV seroconversion to CD4+ cell counts of 200, 350, and 500 cells/mm³ are lacking but are needed to inform health care planners of the likely impact and cost effectiveness of these and possible future changes in CD4+ cell count initiation threshold.

METHODS

Using Concerted Action on Seroconversion to AIDS and Death in Europe data from individuals with well-estimated dates of HIV seroconversion, we fitted mixed models on the square root of CD4+ cell counts measured before combined antiretroviral therapy (cART) initiation. Restricting analyses to adults (age >16 years), we predicted time between seroconversion and CD4+ cell count <200, <350, and <500 cells/mm³ as well as CD4+ cell count distribution and proportions reaching these thresholds at 1, 2, and 5 years after seroconversion.

RESULTS

Median (interquartile range [IQR]) follow-up for the 18495 eligible individuals from seroconversion while cART-free was 3.7 years (1.5, 7). Most of the subjects were male (78%), had a median age at seroconversion of 30 years (IQR, 25-37 years), and were infected through sex between men (55%). Estimated median times (95% confidence interval [CI]) from seroconversion to CD4+ cell count <500, <350, and <200 cells/mm(3) were 1.19 (95% CI, 1.12-1.26), 4.19 (95% CI, 4.09-4.28), and 7.93 (95% CI, 7.76-8.09) years, respectively. Almost half of infected individuals would require treatment within 1 year of seroconversion for guidelines recommending its initiation at 500 cells/mm³, compared with 26% and 9% for guidelines recommending initiation at 350 and 200 cells/mm³, respectively.

CONCLUSIONS

These data suggest substantial increases in the number of individuals who require treatment and call for early HIV testing.

HIV-1 disease progression and mortality before the introduction of highly active antiretroviral therapy in rural Uganda

OBJECTIVE

To provide estimates of survival and progression to different HIV disease endpoints after HIV infection among adults in a rural Ugandan setting.

DESIGN

A prospective population-based cohort study.

METHODS

Eligible individuals at least 15 years of age with documented HIV seroconversion were recruited from a general population cohort in rural Uganda, along with a randomly selected proportion of HIV-prevalent and HIV-negative individuals. All participants were followed up every 3 months, and CD4 cell counts taken every 6 months in HIV-positive participants. Life tables and Kaplan-Meier functions were used to estimate survival patterns for all endpoints [death, time to World Health Organization (WHO) stage 2, 3, AIDS and CD4 cell count < 200 cells/mul]. Analysis of follow-up time was truncated when antiretroviral therapy (ART) became available in the area in January 2004.

RESULTS

We recruited 240 HIV incident cases, 108 prevalent cases and 257 HIV-negative controls. Crude mortality rates were 70.0 per 1000 person-years in HIV-positive, and 12.1 per 1000 person-years in HIV-negative individuals. The median time from seroconversion to death was 9.0 years (N = 240) and 6.2 years to a CD4 cell count less than 200 cells/mul or WHO stage 4 (N = 229). The median time from ART eligibility (CD4 cell count < 200 cells/mul, < 350 cells/mul and WHO stage 3, or WHO stage 4) to death was 34.7 months. Older age at seroconversion was a risk factor for faster progression to death and ART eligibility.

CONCLUSION

HIV progression in this African cohort is similar to that reported in industrialized countries before the widespread introduction of ART.

Aggressive HIV-1?

New York City health officials announced on February 11, 2005 that a patient rapidly developed full-blown AIDS shortly after being diagnosed with a rare, drug-resistant strain of HIV-1. The New York City Department of Health issued an alert to all hospitals and doctors and a press conference was held to announce the emergence of an aggressive HIV-1 strain that may be difficult to treat and that appears to trigger rapid progression to AIDS. Is the panic justified?

[AIDS-free time and survival of an injecting drug users HIV seroconvertors cohort]

OBJECTIVE

To analyze AIDS free time, survival and the pre-AIDS survival for a injecting drug users cohort (IDU) of HIV seroconvertors.

SUBJECT AND METHODS

Interval for seroconversion was available for 276 IDUs from Centers for AIDS Information and Prevention (CIPS) recruited between 1987 and until June of 1996. AIDS diagnosis and vital status dates were obtained by follow up at hospitals, mortality and AIDS registries, and CIPS visits. The end of follow up was December of 1996. Seroconversion date was estimated as the middle point between last HIV- and first HIV+. Kaplan-Meier extension and Cox regression for truncated data were fitted to estimate AIDS-free and survival times and to observe differences by sex, age consumption time and year of seroconversion. Weibull, and Log-normal parametric models were fitted to estimate median and percentiles of AIDS-free and survival times distribution.

RESULTS

34 cases have been identified as AIDS, 24 as deaths, 9 of them being before AIDS. 63.5% of the individuals were AIDS-free 7 years after seroconversion, and the probability of death was 25.50. Pre-AIDS mortality is around 8.7%. There were not significant differences by sex, age, consumption time and year of seroconversion. Log-normal model fitted better estimating an AIDS-free median time of 10.93 years and 13.67 survival years.

CONCLUSION

The incubation period of HIV infection in a cohort of seroconvertors in our environment was around 11 years, not different from that observed out of the Mediterranean area as Holland, Scotland or United States

Cell analysis for hematopoietic stem/progenitor cell transplantation

Cytometric analysis has become an important aspect in the quality control of cells in all phases of hematopoietic cell transplantation. In the stage of donor conditioning the counting of stem and progenitor cells is important and several reliable single platform tests for CD34+ cells have become available recently. It has been shown, that the count of certain subsets of CD34 may predict best time for harvesting stem cells better than just CD34. In many cases manipulation of the cell sample after collection from the donor is necessary before the cells are adequate for transplantation. Characterization of the resulting cell preparations requires reliable quantitative analysis of a variety of cell types like the enumeration of T-cells at the level of one in ten thousand for some allogeneic transplantations. It is discussed how these clinical requirements will need a refinement of cytometric procedures to achieve adequate clinical decisions.

Distribution of CD4+ T-lymphocytes levels in patients with clinical symptoms of AIDS in three west African countries

OBJECTIVES

To study the CD4 T-lymphocyte distribution in patients with clinical signs suggestive of AIDS in West Africa.

DESIGN AND METHODS

Selected patients had clinical AIDS, according to the WHO clinical definition of AIDS in Africa. Serum samples were tested for the presence of HIV antibodies with two different enzyme immunoassays (EIA), and whole blood was used to determine the CD4 lymphocyte levels of each patient, using the TRAx CD4 Test Kit.

RESULTS

In patients with AIDS, the mean CD4+ cell level was 466/microliter; 34% of patients had less than 200/microliter and 62.1% less than 400/microliter. In patients with clinical AIDS but without HIV antibodies, the mean CD4+ cell level was 807/microliter; with 4% below 200/microliter and 14.7% below 400/microliter. The optimal CD4+ cell cut-off between the two groups of patients (with and without antibody to HIV) was 400/microliter.

CONCLUSIONS

The mean CD4 cell levels of AIDS patients was more than twice the 200 CD4+ cells/microliter which, alone or associated with clinical criteria is used to differentiate HIV seropositive patients with and without AIDS. A cut-off of 400 T-lymphocyte equivalents per microlitre (TLE/microliter) will be more appropriate. Only 4% of the anti-HIV negative patients had < 200 CD4 TLE/microliter, and could be infected with unknown immunodeficiency viruses.

Associations of age, immunosuppression, and AIDS among homosexual men in the Tricontinental Seroconverter Study

To characterize the associations of age, immunosuppression, and AIDS outcomes, we evaluated serial measures of CD4+ lymphocytes from 376 homosexual men with documented dates of HIV-1 seroconversion registered in the Tricontinental Seroconverter Study. Using regression models and adjusting for variation within individuals, we found no association between age and the number of CD4+ lymphocytes at seroconversion or with CD4+ lymphocyte decline after seroconversion. Men who developed opportunistic infections had fewer CD4+ lymphocytes at the time of diagnosis compared with men who developed AIDS-defining Kaposi's sarcoma. Older age was significantly associated with higher numbers of CD4+ lymphocytes in individuals diagnosed with AIDS-defining Kaposi's sarcoma but was not significant for individuals with opportunistic infections. Because older age shortens the latency period of Kaposi's sarcoma and does not affect the CD4+ lymphocyte loss, it results in higher CD4+ lymphocytes at the time of diagnosis. These findings suggest distinct biologic mechanisms for various AIDS manifestations, which is important for clinical decision making and health care planning.

Factors associated with the CD4+ lymphocyte count at diagnosis of acquired immunodeficiency syndrome. The AIDS IN EUROPE Study Group

To assess which factors are associated with the CD4+ lymphocyte count at the time of AIDS diagnosis we studied 3046 patients in the AIDS IN EUROPE study who were diagnosed with AIDS in 1 of 17 European countries between 1979 and 1989 and for whom the CD4 count at AIDS diagnosis was known. Data were extracted retrospectively from patient case notes, using a standardized form. There was a wide range of average CD4+ lymphocyte counts at AID diagnosis, according to which diseases were present at diagnosis. The highest geometric mean CD4+ lymphocyte counts at AIDS diagnosis were associated with the diagnosis of extrapulmonary tuberculosis, Kaposi's sarcoma, and non-Hodgkin's lymphoma while the lowest counts were found when histoplasmosis and cytomegalovirus (CMV) retinitis were present. There were no appreciable differences between CD4+ lymphocyte counts at AIDS in patients according to the three major transmission route categories (sex, age, or region of diagnosis) but there was a marked trend (p < 0.005) toward lower CD4+ lymphocyte counts at AIDS diagnosis in more recent years. These associations remained largely unchanged after adjustment for other factors.

Active confrontational coping predicts decreased clinical progression over a one-year period in HIV-infected homosexual men

The association between stressful life events, psychiatric symptoms, coping, and social support and HIV disease progression one year later were studied in 51 HIV-infected asymptomatic and early symptomatic homosexual men. Dependent variables were CD4 counts and clinical progression. No associations between the psychosocial parameters and CD4 counts were found. Active confrontation with HIV infection as a coping strategy was predictive of decreased clinical progression at one year follow-up, after taking into account baseline biomedical and behavioral variables. These results show that active coping strategies may have an effect on disease progression, possibly mediated by greater compliance with medical treatments or by psychoneuroimmunological mechanisms.

Epidemiologic background and long-term course of disease in human immunodeficiency virus type 1-infected blood donors identified before routine laboratory screening. Transfusion Safety Study Group

BACKGROUND

The long-term course of human immunodeficiency virus type 1 (HIV-1)-related disease among seropositive blood donors has not been described. The enrollment and epidemiologic background of HIV-1-infected donors in the Transfusion Safety Study and their immunologic and clinical progression are described.

STUDY DESIGN AND METHODS

Through the testing of approximately 200,000 sera from donations made in late 1984 and early 1985, 146 anti-HIV-1-positive donors and 151 uninfected matched donors were enrolled. These two cohorts were followed with 6-month interval histories and laboratory testing.

RESULTS

Seropositive donors detected before the institution of routine anti-HIV-1 screening disproportionately were first-time donors and men with exclusively male sexual contacts. The actuarial probability of a person's developing AIDS within 7 years after donation was 40 percent; the probability of a person's dying of AIDS was 28 percent. AIDS developed more often when the donor was p24 antigen-positive at donation. Over a 3-year period, significant decreases occurred in CD4+, CD2+CD26+, CD4+CD29+, and CD20+CD21+ counts, but not in CD8+ subsets, CD20+, or CD14+.

CONCLUSION

The high proportions of first-time donations and exclusively homosexual men among seropositive donors suggest that test-seeking may have contributed to the high HIV-1 prevalence in the repository. Implementation of alternative test sites when routine donor screening began in 1985 may have averted many high-risk donations. The disease course in HIV-1-infected donors had the same wide spectrum of immunologic and clinical manifestations as were reported for other cohorts.