摘要:

Objective:To assess the effect of zidovudine on productive HIV infection of the brain.Design:To correlate the incidence of HIV-specific neuropathology with zidovudine therapy.Patients:We examined 192 AIDS cases neuropathologically; 97 had never been treated with zidovudine, 72 had received zidovudine for over 3 months and until death, 23 had their treatment terminated more than 1 month before death.Results:The incidence of HIV encephalitis/HIV leukoencephalopathy (HIVE/HIVL) and of multinucleated giant cells (MGC) was significantly lower in patients who had received zidovudine than in those who had never received zidovudine. The yearly incidence of HIVE/HIVL increased between 1982 and 1987 probably because of improved survival, and decreased between 1987 and 1990 although the percentage of patients treated with zidovudine increased. Since 1991 the incidence of HIVE/HIVL and of MCC increased slightly. The percentage of patients treated with zidovudine until death decreased and that of patients whose treatment was terminated increased concomitantly. In 1989 and 1990, most patients whose treatment was terminated had MGC and HIVE/HIVL. In 1991 and 1992 this incidence decreased markedly, coinciding with the introduction of dideoxyinosine therapy.Conclusion:Zidovudine treatment significantly reduces the occurence of productive HIV infection of the brain in AIDS. Discontinuing zidovudine therapy may favour the occurrence of HIV encephalitis. Substitution therapy with dideoxyinosine also appears to protect against HIV-specific brain pathology.

ISSN:0269-9370    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Objective:To quantitatively demonstrate the pattern of cerebral perfusion abnormalities in HIV-1-infected individuals described as ‘patchiness' or inhomogeneity in previous qualitative emission tomographic imaging studies.Design:We aimed to create a quantitative measure of inhomogeneity in HIV-infected individuals. High-frequency variance in cortical profiles is an indication of inhomogeneity in the distribution of radiotracer in the cerebral cortex. Therefore, the study analysis was designed to enable the estimation of variance frequencies in cortical profiles.Methods:Regional cerebral blood flow was examined in nine mildly demented and 10 cognitively normal HIV-1-seropositive individuals and eight seronegative normal controls using single photon emission computed tomography with the radiotracer [1–123]-N-isopropyl-p-lodoamphetamine. Quantitative analysis was performed using circumferential profiles of cerebral cortical perfusion. Fourier transform power spectra of the profiles were examined as an index of patchiness in tracer distribution.Results:Normal controls were characterized by strong middle frequency and weak high-frequency power. Both HIV-1-infected groups showed a significant power shift from middle to high frequencies.Conclusions:Increased high-frequency variations in both HIV-1-infected groups indicates diffuse cortical perfusion changes compared with normal controls. This study suggests that there are cerebral bloodflow abnormalities in HIV-1-infected individuals both with and without clinically severe dementia.

ISSN:0269-9370    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Objective:To assess whether postprandial dietary thermogenesis contributes to weight loss during HIV infection.Methods:The thermogenic response to a test meal (15 kcal/kg) was evaluated with indirect calorimetry in 16 HIV-infected patients in a stable condition and compared with a control group. Patients were compared according to AIDS (n = 8) or non-AIDS (n = 8) status and to body weight loss (WL; n = 9) or no loss (NL; n = 7). Indirect calorimetry was performed after fasting 6h and during 5h after the test meal.Results:Maximum value of energy expenditure was reached later in the WL group than in the control and NL group (200 versus 30min, respectively). Energy expenditure returned to the initial value 300 min after the test meal (last measurement) in the control group but remained elevated in the patient group. Energy expenditure after food intake was more elevated in HIV-infected patients than in controls, especially in patients with detectable clinical change in their nutritional status (0.96 versus 0.72 kcal/kg body weight).Conclusion:Both kinetics and quantitative aspect of dietary thermogenesis are modified during HIV infection and the different variations are dependant on the extent of body weight loss.

ISSN:0269-9370    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Objective:To evaluate the incidence of HIV infection among men in the Army Reserve Components (RC) in the United States.Methods:A prospective follow-up evaluating HIV seroconversions among men in the RC. Men who were initially seronegative were followed over time and periodically retested. The duration of follow-up was measured for each individual. Date of seroconversion was estimated to be the mid-point between last negative and first positive test. Demographic characteristics were evaluated for association with seroconversion, and incidence density between 1985 and 1991 was examined.Results:We followed 733 622 RC men for 1 988 622 person-years between 1985 and 1991, and identified 534 seroconversions. Demographic correlates of risk included racial/ethnic minorities, age between 20 and 34 years, never having married, residence in an area with a low median income, and residence in metropolitan areas with high incidence of AIDS. Among most of these groups, the incidence density did not change substantially or significantly from the period 1985–1987 to 1991.Conclusions:The patterns of HIV infection are generally similar to those for reported AIDS cases. The incidence density over time is consistent with projections that AIDS incidence will plateau in the United States in the mid- to late-1990s.

ISSN:0269-9370    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Objective:To describe the pattern of newly diagnosed HIV infection in Australia, between 1984 and 1992.Methods:State and Territory health authorities reported cases of newly diagnosed HIV infection to the national HIV surveillance centre. Information sought on each case included the State or Territory of diagnosis, the case identifying number, the sex, date of birth and postcode of residence of the person with newly diagnosed HIV infection, the source of exposure to HIV and the date of specimen collection for the diagnosis of infection.Results:By the end of December 1992, a total of 16 765 cases of newly diagnosed HIV infection had been reported in Australia. The annual number of cases declined between 1985 and 1992. Most diagnoses were among males, and exposure to HIV was attributed to male homosexual contact for more than 80% of cases for which information on exposure to HIV was available. Cases of HIV infection attributed to heterosexual contact represented an increasing proportion of the annual number of diagnoses over the period 1985–1992, among both men and women.Conclusion:National surveillance for newly diagnosed HIV infection has complemented national surveillance for diagnoses of AIDS as a key mechanism for monitoring the course of the HIV epidemic in Australia. The pattern of newly diagnosed HIV infection was similar to the pattern of AIDS diagnoses, with the overwhelming majority of diagnoses of infection being in adult males whose exposure to HIV was attributed to homosexual contact. Limitations of HIV surveillance include the lack of information on HIV testing patterns, incomplete information on HIV exposure histories and duplication of reported diagnoses.

ISSN:0269-9370    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Objective:To describe epidemiological trends in injecting and equipment sharing among a sample drawn from a drug-using population with a high rate of HIV infection.Design:A structured interview was administered prior to treatment to cross-sectional samples of drug users over the period 1988–1991. Reports of injecting, sharing and HIV infection were compared annually.Setting:Lothian Health Board's Community Drug Problems Service is a secondary level service offering harm reduction and treatment of dependency.Participants:A total of 734 consecutively referred drug users resident in Edinburgh. Re-referrals in the same calendar year were excluded.Measures:History of injecting and sharing, recent injecting and sharing, HIV testing history, drugs used in previous month and substitute prescription status.Results:Large reductions in the frequency of injecting were found over the 4 years even among those who were not receiving oral substitutes. More participants in latter years were receiving prescriptions combining opioids and benzodiazepines. Fewer of those interviewed latterly had ever shared injecting equipment. Among recent injectors just as many share equipment as previously. HIV prevalence did not vary significantly over the period. An HIV prevalence of 19% was reported among recent injectors.Conclusions:Edinburgh's drug users are engaging in far safer drug-taking behaviour than previously. Levels of HIV in this population suggest that the epidemic is being contained. A small number persist in high risk drug-related activities. Further investigation of the characteristics of these individuals and the need to develop novel methods of influencing their behaviour are recommended.

ISSN:0269-9370    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Objective:To describe and understand the genesis of the explosive 1988 HIV epidemic among Thai injecting drug users (IDU) in Bangkok.Design:Two cross-sectional HIV seroprevalence sample surveys (SP-1 and SP-2) of drug users, including IDU at various stages of treatment. SP-1, a 10-week estimate of prevalence, was conducted by the Bangkok Metropolitan Administration (BMA) in their detoxification clinics from 5 January to 7 March 1988. SP-2 estimated prevalence in 1 week, 12–15 September 1988, in the same 18 BMA clinics. Both surveys included an administered questionnaire that gathered demographic and behavioral information.Methods:Analysis of HIV prevalence by clinic in both SP-1 and SP-2, and the relationships between demographic data, behavioral variables, arrest history and HIV positivity in SP-1.Results:Data from individual clinics in SP-1 show significant increases in HIV prevalence among IDU sampled from early February 1988. Of IDU sampled in five ‘early’ clinics before 9 February, 2% were positive; in the 13 ‘late’ clinics sampled from 9 February until 7 March, 27% were positive. By September 1988, however, the early and late clinics were no longer heterogenous for HIV prevalence. For current IDU, HIV-positivity was associated with the sharing of injection equipment in SP-1 [odds ratio (OR), 1.82; 95% confidence limits (CL), 1.31–2.53] and recent jail or prison stay (OR, 2.15; 95% CL, 1.18–3.98).Conclusions:The behavioral factors associated with the HIV epidemic among Bangkok's IDU are similar to those described elsewhere. The monthly incidence of 5% from February to September 1988 suggests extensive needle or injection equipment sharing networks among IDU in Bangkok. Additionally, the pattern of HIV-positivity by detoxification clinic over time in early 1988, and then in September 1988 is consistent with a relationship to the prison amnesty of early December 1987. Shortly after that date, an undisclosed number of former IDU, a substantial number of whom were still injecting, and may have become HIV-positive while in custody, returned to resume injecting within existing drug-using networks throughout Bangkok and elsewhere in Thailand.

ISSN:0269-9370    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Objective:To determine risk factors for HIV-1 infection in female commercial sex workers (CSW) in northern Thailand.Methods:A cross-sectional survey of female CSW from 11 sex establishments frequented by military conscripts that included an interview and serological testing for HIV-1.Results:The HIV-1 seroprevalence in 230 CSW was 65%; the rate was lower among CSW from Chiang Mai than from rural areas. Multivariate logistic regression analysis for HIV-1 included the following significant factors: non-urban location of the sex establishment, ethnic Thai lowlander, lower price, history of genital warts and dysuria. Condom use, number of partners and duration of employment were not significantly associated with HIV-1 prevalence after adjustment for other risk factors.Conclusions:The high level of HIV-1 seroprevalence in this sample demonstrates the risk of transmission in lower cost commercial sex encounters in northern Thailand. Non-Thais (ethnic Hill tribes and Burmese) had lower HIV-1 prevalence than ethnic Thais. Type of establishment (‘direct’ brothel-based or ‘indirect’ establishments) was not predictive of HIV-1 seroprevalence. However, rural establishments were less vigilant in promoting condom use, suggesting the need for renewed efforts to enforce the Ministry of Public Health's ‘100% Condom Campaign’ in commercial sex establishments.

ISSN:0269-9370    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Objectives:This study explores how mathematical models can be used to examine the relationship between the effectiveness and costs of different prevention strategies. The analysis, based on a model designed to simulate the spread of HIV in sub-Saharan Africa, illustrates how the impact and relative cost-effectiveness of a prevention programme are sensitive to a number of factors including the rate of spread of HIV prior to the introduction of the programme, the measure used to evaluate the impact of the programme, and the point when the programme is introduced in the epidemic.Results:Assessing the impact and cost-effectiveness of different HIV prevention strategies is problematic. Not only are there difficulties in collecting the relevant data, but the impact of a prevention programme may be highly non-linear in character because of the many factors that determine the net rate of viral transmission. The long incubation period of HIV further complicates the analysis as the benefits from preventing a case of infection extend over a number of years.Conclusions:The results highlight the need to collect more data on the impact and costs of prevention programmes if we are to ensure that the available resources for HIV prevention are to be used both efficiently and equitably.

ISSN:0269-9370    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Objective:To study rates of documented HIV seroconversion and syphilis as a cofactor for seroconversion in sexually transmitted disease (STD) clinics. In the main clinic the HIV seroprevalence rate was 12% and most infections had been shown to be acquired by heterosexual contact.Methods:We analyzed computer records of patients who had at least two HIV-antibody tests between 1 December 1987 and 31 December 1990, at STD clinics in Dade County (Miami), Florida.Results:Of 5164 individuals with two HIV tests, 208 (4.0%) seroconverted. The overall seroconversion rate was 3.1 per 100 person-years. Among blacks, who accounted for 77% of seroconversions, the rate was higher for women (4.8) than for men (2.7). The highest rate was in 15–19-year-old black women (7.1 per 100 person-years). The HIV seroconversion rate was 12.8 for patients with primary or secondary syphilis diagnosed between two HIV tests, 3.1 for patients who acquired syphilis before their first HIV test, and 2.3 for patients who had never had syphilis. Eighteen per cent of all HIV seroconversions were attributable to syphilis acquired in the interval between two HIV tests.Conclusions:We found high HIV seroconversion rates, especially among black teenagers and black women, in an STD clinic population in which the majority of HIV infections were shown previously to have been acquired heterosexually. Syphilis was a marker for HIV seroconversion and syphilitic ulcers may facilitate HIV transmission. Innovative prevention programs directed towards women and adolescents should be developed and evaluated.

ISSN:0269-9370    

出版商:OVID    

年代:1994

数据来源: OVID