HIV infection and risk behaviours among young gay and bisexual men in Vancouver

BACKGROUND: Young gay and bisexual men may perceive that the consequences of HIV infection have dramatically improved with the availability of highly active antiretroviral therapy. We therefore sought to identify trends in HIV infection rates and associated risk behaviours among young gay and bisexual men in Vancouver. METHODS: Prospective cohort study involving gay and bisexual men aged 18-30 years who had not previously tested HIV positive. Subjects were recruited through physicians, clinics and community outreach in Vancouver. Annually participants were tested for HIV antibodies and asked to complete a self-administered questionnaire pertaining to sociodemographic characteristics, sexual behaviours and substance use. Prevalence of HIV infection and risk behaviours were determined for eligible participants who completed a baseline questionnaire and HIV testing as of May 1998. The primary outcome was the proportion of men who reported having protected sex during the year before enrollment and who reported any episode of unprotected sex by the time of the first follow-up visit. RESULTS: A total of 681 men completed a baseline questionnaire and HIV testing as of May 1998. The median duration between baseline and the first follow-up visit was 14 months. The median age was 25 years. Most of the subjects were white and of high socioeconomic status. The majority (549 [80.6%]) reported having sex only with men; 81 (11.9%) reported bisexual activity. Of the 503 men who had one or more regular male partners, 245 (48.7%) reported at least one episode of unprotected anal sex in the year before enrollment; the corresponding number among the 537 who had one or more casual male partners was 140 (26.1%). The prevalence and incidence of HIV seropositivity were 1.8% (95% confidence interval [CI] 0.8%-2.8%) and 1.7 per 100 person-years [95% CI 0.7-2.7], respectively. Fifty-two (26.5%) of the 196 and 55 (29.7%) of the 185 men with regular partners who reported having practiced protected insertive and receptive anal sex in the year before the baseline visit reported engaging in these activities without a condom at the follow-up visit; the corresponding numbers among the 232 and 242 men with causal partners who had practiced protected insertive and receptive anal sex before the baseline visit were 43 (15.5%) and 26 (9.4%) respectively at follow-up. INTERPRETATION: The incidence of HIV infection is unacceptably high among this cohort of young gay and bisexual men. Preliminary results suggest a disturbing trend toward increasing levels of unprotected anal intercourse.     

Impact of gene-modified T cells on HIV infection dynamics

Previous clinical trials in HIV-infected patients involving infusion of T cells protected by an antiviral gene have failed to show any therapeutic benefit. The value of such a treatment approach is thus still highly controversial. In this study, the anticipated effects of gene-modified cells on virus and T-cell kinetics are analysed by mathematical modeling. Because technically only a small fraction of all T cells in a patient can be manipulated ex vivo, therapeutic success will depend on the accumulation of gene-modified cells after infusion into the patient by in vivo selection. Our simulations predict that a significant therapeutic benefit is conferred only by antiviral genes that inhibit HIV replication before virus integration (class I genes). Genes that inhibit viral protein expression (class II, used in previous clinical trials), require a much higher inhibitory activity than class I genes to promote the regeneration of T cells and reduce the viral load. Inhibition of virus assembly and release alone (class III) confers no selective advantage to the T cell and is therefore ineffective unless combined with class I (or, possibly, class II) genes. Also crucial in determining the clinical outcome are the regenerative capacity of the gene-modified cells and the level of HIV replication in the patient. These results can be important for guiding future strategies in the field of gene therapy for HIV infection.     

Cytopathologic findings in breast masses in men with HIV infection

OBJECTIVE: To report the cytologic findings on 15 men with HIV infection who presented with breast masses and underwent fine needle aspiration (FNA). STUDY DESIGN: The cytopathology files of The Johns Hopkins Hospital (JHH) and the University of Texas Southwestern Medical Center (UTSW) were searched for cases of men with breast masses evaluated by FNA. The HIV status of these men was then ascertained. A total of 15 cases (9 at JHH, 6 at UTSW) of 259 (5.79%) were identified in which the patient was HIV seropositive. The pathologic diagnoses were reviewed, and the clinical history, along with the medication list at the time of FNA, was determined. RESULTS: The men ranged in age from 12 to 51 years (mean, 38). Breast masses were present on either the right (n = 6) or left (n = 7) side or were bilateral (n = 2). In all 15 cases, the masses were retroareolar, firm and tender. FNA showed a ductal and stromal proliferative process, often with focal cytologic atypia and numerous background naked myoepithelial nuclei, features consistent with a diagnosis of gynecomastia. Thirteen of these men were on drug regimens, which included indinivir, stavudine and saquinivir. Two of the men were on azidothymidine only. CONCLUSION: Gynecomastia, although rare in young men, was the sole cause of breast masses in HIV-seropositive men in this study. It has been described as an extremely rare side effect of certain antiretroviral medications, including indinivir, stavudine and saquinivir. FNA is an important tool in determining the benign nature of these lesions and excluding other causes of breast masses in this patient population, such as infections, malignant lymphoma and breast carcinoma.     

Pathophysiology of thrombocytopenia associated with HIV infection in homosexual men. A preliminary report

The pathophysiology of HIV associated immune thrombocytopenia (HIV-ITP) and its response to AZT was investigated. Using autologous 111Indium-labelled platelets, platelet kinetic were analysed in two patient groups. Group 1 (untreated) was comprised of 13 patients with HIV-ITP. Group 2 (AZT) was comprised of 6 patients with a history of HIV-ITP prior to starting AZT. These patients were studied following a rise in their platelet count on AZT. Platelet survivals in both groups were shortened compared to controls, however there was no significant difference between the 2 groups. However platelet turnover rates were significantly depressed in Group 1 compared to Group 2 (P less than 0.05) and control values (P less than 0.05). The platelet count correlated with platelet turnover in Group 1 but not in AZT treated patients. Thus patients with HIV-ITP appear to have both shortened survivals and suppressed platelet production. The mechanism of the latter is unknown, but the increased turnover rate seen with AZT suggests it is a direct or indirect effect of the HIV virus.     

Psychological and social problems in HIV infection: interviews with general practitioners in London.

OBJECTIVE--To assess current practice and opinions of general practitioners in London about managing psychological and social problems relating to HIV infection. DESIGN--A stratified random sample of general practitioners, including those with a range of experience of people with HIV infection, were interviewed by medically trained interviewers. SETTING--Doctor''s surgeries. PARTICIPANTS--270 General practitioners working within the area covered by London postcodes. RESULTS--Two thirds of doctors had treated at least one patient with HIV infection and described their work with these patients. General practitioners were counselling and educating many of their patients about AIDS and associated risk behaviours and were aware of the need for careful attention to confidentiality. Doctors with no experience of patients with HIV infection were often older, in singlehanded practice, less inclined to deal with drug abusers or to counsel their patients on risk behaviours, and more in favour of insurance companies'' policies towards people with HIV infection. CONCLUSIONS--General practitioners in London are quickly becoming involved in the care of patients with HIV infection and their relatives and friends. Many are counselling patients and testing for antibodies themselves and regard this as an integral part of their work. A considerable workload in primary care comprised patients who obsessively fear contracting HIV infection.     

Some experience in an area health authority child health clinic.

Three years'' experience as a doctor taking two clinics a week in an area health authority child health clinic was reviewed. A wide range of clinical conditions was seen, including: problems associated with feeding in breast- and bottle-fed infants; minor developmental abnormalities (mental, behavioural, and physical); surgical and orthopaedic conditions requiring treatment; medical conditions, mainly respiratory and alimentary infections, skin conditions, and problems of over-treatment for minor ailments; and minor genetic abnormalities. Mothers asked for advice on a wide range of topics, risks and benefits of immunisation being the most common. The clinic doctor needs a wide experience in paediatrics to deal with such problems. It is suggested that all lecturers in child health and paediatric and senior registrars should take one clinic a week for six months, and all medical students should attend some clinics as part of their paediatric training. Health visitors have an important role in helping the clinic doctor, but their training should be more realistic and appropriate facilities should be provided to keep them up to date in their work.     

Simulation model for planning renal services in a district health authority.

OBJECTIVE--To investigate the use of a computer simulation model in planning and budgeting for renal replacement services. SETTING--Regional renal unit. RESULTS--The simulation provided projections that accurately reflected the actual numbers of people maintained on different forms of renal replacement therapy in previous years. Projections up to the end of the century showed that with no change in the demand for the service the total number of people on the renal replacement programme would increase by 40%. Increasing the uptake of new patients from 40 per million to 55 per million would mean an increase of 66% in patient numbers over the same period. Similarly, at present day prices the cost of providing the service would rise by 31% with no change in demand and by twice this with the greater uptake of new patients. Increasing the number of transplant operations was shown to offer little prospect of a reduction in these costs. CONCLUSION--The simulation program could be used by individual renal units to evaluate different treatment policies and to budget for resource use. Even at current demand levels resource requirements for renal replacement therapy will continue to grow until after the end of the century.     

Study of infection with HIV and related risk factors in young offenders' institution.

OBJECTIVES--To estimate the prevalence of infection with HIV in young offenders in Scotland and to obtain information about related risk factors and previous tests for HIV. DESIGN--Voluntary anonymous study with subjects giving saliva samples for testing for HIV and completing questionnaires about risk factors. SETTING--Polmont Young Offenders'' Institution near Falkirk, Scotland. SUBJECTS--421 of 424 available male prisoners in Polmont. The questionnaires of 17 of the prisoners were excluded because of inaccuracies. MAIN OUTCOME MEASURES--Prevalence of infection with HIV and related risk behaviour. RESULTS--68 (17%) of prisoners admitted misuse of intravenous drugs, of whom 17 (25%) admitted having injected drugs while in prison. Three subjects admitted having anal intercourse while in prison. Prevalence of misuse of intravenous drugs varied geographically: 28% (33/120) of prisoners from Glasgow compared with 9% (7/81) of those from Edinburgh and Fife. A high level of heterosexual activity was reported, with 36% (142/397) of prisoners claiming to have had six or more female sexual partners in the year before they were imprisoned. Altogether 8% (32/389) of prisoners had previously taken a personal test for HIV: 50% (9/18) of those who had started misusing intravenous drugs before 1989, 18% (9/49) of those who started misuse later, and only 4% (14/322) of those who had not misused intravenous drugs. No saliva sample tested positive for antibodies to HIV, but 96 prisoners requested a confidential personal test for HIV as a result of heightened awareness generated by the study. CONCLUSIONS--Voluntary, anonymous HIV surveys can achieve excellent compliance in prisons, and the interest generated by the study suggests that prisons may be suitable sites for providing education and drug rehabilitation for a young male population at high risk of future infection with HIV.     

Impact of tuberculosis on serum leptin levels in patients with HIV infection

AIM: Tuberculosis (TB) and human immunodeficiency virus (HIV) are classical wasting diseases accompanied by immunosuppression. As leptin is involved in the weight regulation and cellular immunity, we investigated the role of leptin levels in the co-infection of HIV and TB (HIV-TB). METHODS: The study group consists of the patients with asymptomatic HIV infection (n = 20), patients with HIV-TB co-infection (n = 20) and healthy control subjects (n = 20). Serum leptin levels and the concentrations of IFN-gamma, TNF-alpha, IL-12 and IL-4 cytokines were measured by ELISA before the start of the treatment. CD4+ T-cell counts were determined in patients with HIV and HIV-TB by flow cytometry. Body mass index (BMI) of the study subjects was calculated. RESULTS: Serum leptin levels and BMI were significantly lower in the patients with HIV-TB than control and HIV subjects. Multivariate regression analysis showed that serum leptin concentration was significantly dependent on BMI and sex but not on age and the disease groups. The leptin levels did not correlate either with CD4+ T-cell counts or with any of the serum cytokines in HIV and HIV-TB patients. CONCLUSION: Thus our finding suggests that the leptin concentrations were strongly associated with BMI and gender but not with the disease state or with the circulating cytokine levels.     

Changes in sexual behaviour and the fall in incidence of HIV infection among homosexual men.

To investigate the epidemiology and normal course of infection with HIV the prevalence and incidence of the infection were studied among two cohorts of homosexual men in Amsterdam in 1980-7. The cumulative incidence of infection increased from a weighted 2.2% in 1980 to 39.0% in 1987. The estimated yearly incidence of HIV was 3.0% in 1981, rose to 8.8% in 1984, and fell gradually to 0% in 1987. During the study the sexual behaviour of the cohorts was examined. The number of men with whom anopenetrative intercourse was practised fell from a mean of 10.6 to 1.4 for those positive for HIV antibody, whereas the number with whom anoreceptive intercourse was practised fell from a mean of 3.7 to 0.5 for those negative for the antibody. In addition, there was a reduction in the number of cases of hepatitis B and syphilis among men in general. The decline in infection with HIV was assumed to be linked to changes in sexual behaviour. Such changes practised early in the course of the epidemic probably had a strong effect on the number of cases of AIDS among homosexual men in Amsterdam.