Population Of Gay Men Research Articles

Delayed hypersensitivity skin testing and anergy in a population of gay men

Anergy is almost universal among patients with the acquired immunodeficiency syndrome (AIDS). To determine the prevalence and correlates of anergy in a population at risk for AIDS, we performed skin tests in 1120 gay men who were enrolled in a prospective study of the natural history of human immunodeficiency virus (HIV) infection. Anergy, defined as no induration to any of four intradermal antigens, was present in 12%. Individually, no induration was detected in response to tetanus toxoid (41%), mumps (28%), candida (47%), and trichophyton (72%). Anergy was strongly associated with the presence of antibody to HIV and with a reduced number of T helper lymphocytes, but not independently with generalized lymphadenopathy, the number of reported male sexual partners in the previous 2 years, the number of T suppressor lymphocytes, or with high titers of antibodies to cytomegalovirus. Nine percent of HIV antibody-negative subjects and 20% of antibody-positive subjects were anergic; anergy is not specific for serologically documented HIV infection in this population. Skin testing with only tetanus toxoid, candida, and mumps antigens may be sufficient to detect anergy. In the presence of HIV antibody, the ability of anergy to predict progressive immunodeficiency remains to be determined.

AIDS prevention in Japan and its cost benefit aspects

Since the acquired immunodeficiency syndrome (AIDS) in Japan is in the initial stage of its spread (the first case was reported in 1985, and cumulative cases numbered 21 as of September 1986), we estimated the magnitude of the imminent epidemic using Delphi technique, and analyzed economic performance of preventive health programs. The annual incidence predicted for the years 1988, 1991 and 1996 was 100, 450 and 950, respectively (Japanese population 120 million, calculated cumulative incidence for the initial 5 years 0.4/100000 in Japan, 10.8/100000 in U.S.A.), implying that the AIDS epidemic in Japan would be roughly one-thirtieth of that in the U.S.A. during the initial period. This conservative prediction can be explained by the following factors: the populations of homosexual men and drug abusers are far smaller than those in the U.S.A.; low seroprevalence among homosexual men (4% or less in Japan vs 37–67% in U.S.A.); the absence of buildup in AIDS incidence in the initial period. Preventive programs involve: (i) surveillance and education for hemophiliacs and homosexual men including counselling clinics run with strict confidentiality; (ii) education of physicians and the public, especially travellers to ‘high risk countries’; and (iii) screening of donated blood samples. The outcome of cost-benefit analysis appears to depend on the scale of blood donor screening program. Preventive programs focused on the counselling and education of homosexual men are highly cost-effective. On the other hand, if the screening of all the blood donors in Tokyo and other metropolitan areas is undertaken, the program is bound to yield a net loss under the predicted epidemiologic circumstances.

Functional T lymphocyte immune deficiency in a population of homosexual men who do not exhibit symptoms of acquired immune deficiency syndrome.

To determine whether healthy homosexual men are immunologically impaired, peripheral blood leukocytes (PBL) from 20 male homosexuals were compared prospectively with PBL from 14 age-matched male heterosexual donors with respect to: (a) the capacity of their PBL to generate functional T cell immune responses in vitro; and (b) the content of total T cells and T cell subsets in their peripheral blood. The homosexual donors studied indicated moderate sexual life styles in that all but one of the donors had less than five current sexual partners. The percentages of OKT3+, OKT4+, and OKT8+ T cells were similar to those of heterosexual controls. T cell function was assessed by measuring cytotoxic T cell responses to influenza virus and to allogeneic cells. Approximately one-third of the homosexual donors consistently exhibited weak cytotoxic T lymphocyte (CTL) responses to influenza virus, whereas all of the heterosexual donors generated strong CTL responses to influenza. There was no correlation between the strength of CTL responsiveness to influenza virus and the strength of CTL responses to allogeneic cells. These results suggest that the influenza-specific CTL response may be a sensitive indicator of immunologic defects in asymptomatic homosexuals. If acquired immune deficiency syndrome results from an infectious agent, it remains to be seen if such immunosuppression predisposes to the infection, or if it reflects early consequences of infection.

Immunocompromise syndrome in homosexual men. Prevalence of possible risk factors and screening for the prodrome using an accurate white cell count.

The immunocompromise syndrome in homosexual men in the USA is thought to be associated with cytomegalovirus (CMV) infection and nitrite intake. Such men often have a lymphopenia. In a clinic in London 76% of 46 unselected homosexual men and 50% of 76 heterosexual controls had serum CMV IgG antibody at a titre of 1/16 or more (p less than 0.01). No case of excretion of CMV in the urine was found. Thirty per cent of the homosexual men admitted to using nitrites. These figures suggest that this population of homosexual men uses nitrites less often than their counterparts in the USA and is less likely to have evidence of active or past CMV infection. In addition, these male homosexual patients seem to be less promiscuous than those reported from the USA. Mean accurate total and differential white blood cell counts, using the Haemalog D automatic white cell counter, were no different in homosexual men (and various at risk subgroups of them) than heterosexuals, suggesting that the prodrome to the immunocompromise syndrome was not present in the London clinic population.

Anal warts in a population of gay men in New York City.

Anal warts in a population of gay men in New York City.