R Janssen

University of California, Los Angeles, Los Angeles, CA, United States

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Publications (7)36.15 Total impact

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    NIDA research monograph 02/1997; 172:130-55.
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    ABSTRACT: Most available studies on the psychiatric, neuropsychological, and neurological complications of HIV-1 infection and AIDS have been conducted in Western countries, on samples of well-educated, mostly white, homosexual men. Concerns about generalizability of the results of those investigations prompted the WHO to implement the cross-cultural venture called WHO Neuropsychiatric AIDS study. This project aims to assess the prevalence and natural history of HIV-1-associated psychiatric, neuropsychological, and neurological abnormalities in representative subject samples enrolled in the five geographic areas predominantly affected by the HIV-1 epidemic. Assessment is made by a data collection instrument including six modules. The intercenter and intracenter reliability in the use of each module has been formally evaluated. The study consists of a cross-sectional phase and a longitudinal follow-up. The cross-sectional phase was completed in five centers. This paper reports on the results of psychiatric assessment, which revealed a significantly higher prevalence of current mental disorders in symptomatic seropositive persons compared with seronegative controls among intravenous drug users in Bangkok and homosexuals/bisexuals in São Paulo. The mean global score on the Montgomery-Asberg Depression Rating Scale was significantly higher in symptomatic seropositive individuals than in matched seronegative controls in all centers. These results suggest that the significance of the psychopathological complications of symptomatic HIV-1 infection may have been underestimated by previous studies conducted on self-selected samples of well-educated, middle-class, mostly white, homosexual men.
    Archives of General Psychiatry 02/1994; 51(1):39-49. · 13.77 Impact Factor
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    ABSTRACT: The neuropsychological and neurological complications of HIV-1 infection and AIDS were explored within the cross-sectional phase of the WHO Neuropsychiatric AIDS Study. Special attention was devoted to the controversial issue of the prevalence and clinical significance of subtle cognitive deficits in asymptomatic seropositive subjects. A neuropsychological test battery validated for cross-cultural use, a structured interview for the diagnosis of dementia, a rating scale of functioning in daily living activities, and a neurological module were administered to representative samples of seropositive subjects and to matched seronegative controls living in the five geographic areas predominantly affected by the HIV-1 epidemic. Data are available for five centers. The prevalence of global neuropsychological impairment was significantly increased in asymptomatic seropositive subjects compared with controls in only two centers. A significant effect of education on neuropsychological performance was observed among asymptomatic seropositive individuals. In the two African centers, low-education, but not high-education, asymptomatic seropositive persons had an impaired performance. The frequency of impaired functioning in daily living activities and of neurologic abnormalities was higher in symptomatic, but not in asymptomatic, seropositive subjects compared with controls in all centers. These data suggest that the risk of subtle cognitive deficits may be increased in asymptomatic stages of HIV-1 infection. However, these deficits are not associated with neurologic changes and do not seem to affect subjects' social functioning.
    Archives of General Psychiatry 02/1994; 51(1):51-61. · 13.77 Impact Factor
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    ABSTRACT: In the course of the preparatory work for the WHO cross-cultural study on the neuropsychiatric aspects of HIV-I infection, two new neuropsychological tests (the WHO/UCLA Auditory Verbal Learning Test and the Color Trails 1 & 2) were developed. The evaluation of these tests was performed at four sites, two in developed and two in developing countries. The data obtained suggest that the tests are more culture fair than others currently used to assess the same functional domains, that they are sensitive to HIV-1-associated cognitive impairment, and that this sensitivity “holds” across different cultures.
    Archives of Clinical Neuropsychology 03/1993; · 2.00 Impact Factor
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    ABSTRACT: Because little was known about the prevalence of neurological complications of human immunodeficiency virus type 1 (HIV-1) infection in Africa, we conducted a cross-sectional study among consecutive admissions to the internal medicine wards of Mama Yemo Hospital in Kinshasa, Zaire. Of the 196 patients studied, 104 (53%) were HIV-1 seropositive, of whom 50 (48%) had stage 3 and 49 (47%) had stage 4 HIV-1 infection according to the provisional WHO staging criteria for HIV infection. Neuropsychiatric abnormalities were present in 43 (41%) of 104 HIV-1-seropositive patients. Of the HIV-1-seropositive patients, 9 (8.7%; 95% confidence interval, 4-16%) were diagnosed as having possible HIV-1-associated dementia complex, 1 (1%) as having possible HIV-1 myelopathy, and 3 (2.7%) as having possible HIV-1-associated minor cognitive/motor disorder. Definitive diagnoses could not be made because there were no facilities for neuroimaging and neuropathology. Meningitis caused by cryptococcus was diagnosed in six (5.6%) and by Mycobacterium avium in two (2%) of the HIV-1 seropositive patients. Acute onset hemiplegia, believed to be due to stroke, was present in four (4%) of the HIV-1-seropositive patients. The prevalence of other central nervous system opportunistic infections and mass lesions, especially toxoplasmic encephalitis, could not be assessed. In this population of Zairian inpatients, the prevalence of neurological complications of HIV-1 infection was similar to that observed in industrialized countries among patients with advanced HIV disease.
    Journal of acquired immune deficiency syndromes 02/1992; 5(4):333-40.
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    ABSTRACT: The WHO launched a multicentre study to explore the nature and prevalence of HIV-1-associated neurological, psychiatric, and neuropsychological abnormalities in persons living in different geographical and sociocultural contexts. The study is being conducted in Brazil, Germany, Kenya, Thailand, the United States of America, and Zaire. A comprehensive instrument for the collection of neuropsychiatric data (including a battery of neuropsychological tests suitable for cross-cultural use) has been developed, and the feasibility of the recruitment and assessment procedure designed for the main phase has now been demonstrated.
    The British Journal of Psychiatry 10/1991; 159:351-6. · 6.61 Impact Factor
  • British Journal of Psychiatry, v.139, 351-356 (1991).