A cohort study of HIV infection among intravenous drug users in Ruili and other two counties in Yunnan Province, China, 1992-1995

The blood of the femoral head is thought to be supplied by vessels originating from the medial and lateral circumflex femoral arteries and via the marrow cavity of the neck. Therefore, it is difficult to induce osteonecrosis of the femoral head when the marrow cavity of the neck is preserved. In the present study, we established a new model of femoral head necrosis by dislocating the hip joint and ligating the medial and lateral circumflex femoral arteries and veins. Measurement of femoral head blood flow revealed that a marked decrease to 14.7% of the control value was achieved by both hip dislocation and ligation of blood vessels. Pathologic examination showed no necrosis with either dislocation or ligation alone, whereas at 2 and 4 weeks 80% of the animals subjected to both procedures showed widespread necrosis. These pathologic findings considered in the light of results of the blood flow measurements suggest that a decrease in femoral head blood flow below 20% of the control value is needed to cause osteonecrosis. In addition, magnetic resonance images (MRI) of the model were evaluated in the combined dislocation and ligation group at 4 weeks (n = 5). Changes on MRI were seen in 3 of 5 dogs. The necrotic changes of the femoral head are thought to be detectable on MRI within 4 weeks after ischemia without enhancement.     

Cohort study of HIV infection among drug users in Ruili, Longchuan and Luxi of Yunnan Province, China

Among Hong Kong Chinese blood donors, 99.71 percent were found to be D+. Of these, 55.02 percent were of the phenotype CCDee. The Du phenotype was found to be present in 0.016 percent. Among the 0.27 percent who were apparently D-, 0.079 percent were of the Del phenotype, while the remaining 0.19 percent were "true D-," as defined by a nonreactive eluate obtained by an adsorption and elution procedure using anti-D. The ccdee phenotype constitutes 56.77 percent of the "apparent D-" and 80.24 percent of the true D-. Data show that anti-D rarely occurs in Hong Kong Chinese, and it is postulated that this could be due to the presence of a very weak form of the D antigen among many of those who appear to be D-.     

Determinants of condom use among intravenous drug users

OBJECTIVE: To examine the factors associated with condom use among a cohort of sexually active intravenous drug users (IVDU). DESIGN: Data were collected via personal interview at the fourth-month assessment point of a longitudinal study monitoring HIV infection and risk behaviors among IVDU. SETTING: A community-based methadone clinic. PARTICIPANTS: A total of 158 sexually active heterosexual male and female IVDU, including both methadone patients and out-of-treatment individuals with a history of opiate abuse. MAIN OUTCOME MEASURES: We describe a new approach to identify the determinants of condom use. Previous studies have described subjects as either 'condom users' or 'condom non-users', using an individual's overall behavior as the unit of analysis. By analyzing condom use during the most recent sexual encounter, we avoided the problem of interpreting inconsistent condom use. Data were analyzed using forward stepwise logistic regression. RESULTS: Thirty-four per cent of the heterosexual subjects (n = 160) reported using a condom during their last sexual encounter. Being HIV-positive and having either a causal or commercial partner were each associated with increased probability of using a condom (odds ratio, 10.6, 4.4 and 12.1, respectively). No interactions with sex were found. CONCLUSIONS: Our results suggest that knowing that one is HIV-positive is an important determinant of condom use; HIV testing may therefore increase the use of condoms. In addition, interventions to change sexual behaviors may need to focus on the type of sexual partner.     

Cryptosporidiosis among HIV positive intravenous drug users in Malaysia

A study conducted at the Tampin Drug Rehabilitation Center in Malaysia established a high prevalence (23%) of asymptomatic carriers of Cryptosporidium among exposed HIV positive intravenous drug users (IVDUs). A majority of them were young adults and among the ethnic groups, the Malay HIV positive inmates had the highest prevalence of Cryptosporidium infection.     

Contraceptive behavior among intravenous drug users at risk for AIDS.

Examined factors associated with practicing contraception among 319 street-recruited iv drug users in New York City. The Ss were administered a structured interview covering AIDS risk behaviors, drug use history, and sexual behavior. Slightly over half of Ss (52%) were practicing contraception, primarily with condoms and birth control pills. Among 220 male Ss, contraception was associated with being non-Hispanic, being unmarried, having a home, and AIDS-related changes in drug injection behavior. Among 99 female Ss, it was associated with having multiple sexual partners. Although concern about AIDS was evident in Ss' behavior, there are multiple determinants (ethnic group membership, situational practicalities, and concern about AIDS) in practicing contraception, and the level of contraception among this group will still result in many unwanted pregnancies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mortality among HIV-infected intravenous drug addicts in Stockholm in relation to methadone treatment

The aim of the study was to estimate the mortality rate and evaluate the causes of death in all diagnosed HIV-positive IDUs in the Stockholm area, 1986-90, and to compare the risk of death of those who received methadone treatment with that of those never admitted to or discharged from the programme. Data were collected from the Swedish National Bacteriological Laboratory, the Methadone Maintenance Programme (MMTP) and the Department of Forensic Medicine, as well as from hospitals in the Stockholm region. In Sweden 90% of all IDUs are HIV-tested. Most deceased IDUs are examined forensically. This examination always includes HIV-testing. During the observation period, 472 HIV-infected IDUs were reported from the Stockholm area. Of these addicts 135 participated in the methadone maintenance programme for a shorter or longer time during the study period. Most of them had received the HIV-diagnosis more than 1 year before first entering the programme. Sixty-nine subjects died during the observation period. A majority, 52 persons, died from violence or poisoning. Seventeen died from somatic complications of drug abuse. Nine of them were diagnosed as suffering from AIDS. Eight of the deceased had participated in the MMTP. The relative risk of death from external violence and poisoning was 0.25 (95% confidence interval 0.1-1.0) when participants in the MMTP were compared with HIV-infected IDUs never attending the programme. When all causes of death are compared the relative risk was 0.8. Those patients discharged from the programme have a higher mortality rate than those who never participated.(ABSTRACT TRUNCATED AT 250 WORDS)     

Blood lead of intravenous drug users

Ethanol, morphine, cocaine and amphetamine were examined in place conditioning. After determination of initial preferences, animals were conditioned with ethanol (1 g/kg), morphine (5 mg/kg), cocaine (5 mg/kg) and amphetamine (5 mg/kg) alone or with combinations of these drugs plus naloxone (1 mg/kg). Naloxone prevented the ability of all drugs used to produce a place preference. The reinforcing properties of ethanol and morphine were reduced by sodium nitroprusside at a dose equal to 1/10 of LD50 given before preference testing. Molsidomine (1/10 LD50 and 1/20 LD50) altered the expression of the conditioned place preference produced by ethanol but not by morphine. Results of the present study suggest the involvement of endogenous opioids and probably of nitric oxide in the rewarding actions of drugs of abuse.     

Prevalence of blood-borne viruses among intravenous drug users and alcoholics in Hiroshima, Japan

We investigated the prevalence of human immunodeficiency viruses-1 and 2 (HIV-1 and HIV-2), human T-lymphotropic virus type I and II, hepatitis B virus (HBV), hepatitis C virus (HCV) and hepatitis D virus among intravenous drug users (IVDU) in Hiroshima, Japan, where little is known about their present levels. From June to December 1993, serum samples were collected from 47 IVDU and 98 alcoholics in Hiroshima, Japan, and examined for markers of virus infection. The prevalence of antibody to HCV (anti-HCV) and/or HCV-RNA was significantly higher in IVDU than alcoholics (74.5% vs 20.4%, 44.7% vs 10.2% respectively, P < 0.001). In contrast, the prevalence of antibody to hepatitis B surface antigen and/or core antigen (anti-HBs and/or anti-HBc) showed no significant difference between the 2 groups (57.4% vs 66.3%). HIV-1 infection was found in one (2.1%) IVDU and genome analysis indicated that it was subtype B according to Myers' classification. Thus, an extremely low level of HIV infection and a high level of HCV infection was found in IVDU. Careful follow-up of this group is thought to be needed to minimize an outbreak of HIV-1 infection in Japan.     

Behavior change among intravenous drug users: The role of community-based interventions.

Discusses the role of the community and reviews 4 models of preventing AIDS among drug users: drug treatment, clinic-based interventions, community-based interventions, and community-level interventions. Interventions at the community level are needed to change social norms and to maximize the prospect of preventing AIDS. The obstacles to these interventions include poverty, lack of social capital, multiple social problems in communities where drug use is prevalent, and lack of community consensus about appropriate types of action. To overcome these impediments, psychologists in the addictions can identify the strengths in these communities and catalyze participation in community-level interventions to prevent the spread of AIDS. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Subtype distribution among intravenous drug users with chronic type C hepatitis in southern Spain

The hepatitis C virus (HCV) subtype distribution among intravenous drug users (IVDU), and patients without this risk of acquiring HCV infection, was evaluated. The patients included in the study were 51 with chronic type C hepatitis (36 IVDU and 25 coinfected by HIV-1), and 31 on haemodialysis. Genotyping was performed on 71 viraemic patients, with the following distribution: 25.4%, 1a; 54.9%, 1b; 8.5%, 3a; 7%, mixed (1a, 1b; 3a, 1a; 3a, 1b; 2 x 3a, 2a); 1.4%, 4; and 2.8%, non-typeable. When subtypes were related to IVDU practice, the statistical significance was p < 0.01 for subtypes 1a (48.5% vs 7.5%, for IVDU and non-IVDU, respectively) and 1b (16.1% vs 85.1%). No relation between HIV-1 coinfection and subtype distribution was observed among IVDU patients. The results suggest that among young IVDU of Southern Spain the emerging HCV subtype is 1a.     

The psychology of preventing AIDS among intravenous drug users: A social learning conceptualization.

This article reviews the studies of AIDS risk reduction among IV drug users that have been conducted through early 1988. Almost all studies report risk reduction among the majority of subjects. Three principles are derived from the studies: Basic AIDS information is needed to generate motivation for behavior change; means for behavior change must be provided; and methods for reinforcing the new behaviors must then be provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Prevalence and epidemiologic correlates of human T cell lymphotropic virus infection among intravenous drug users

Intravenous drug users (IVDUs) in Seattle (n = 213) were studied to identify the prevalence and predominant types of and risk factors for human T cell lymphotropic virus (HTLV) infection. Detailed questionnaires, serologic screening, and polymerase chain reaction analysis (for a subset) were used. Evidence of HTLV infection was found in 16.5%, of which 89% were HTLV-II. HTLV infection was significantly associated with nonwhite race, older age, more years of intravenous drug use, prior use of heroin, history of gonorrhea, history of any sexually transmitted disease, hepatitis B virus infection, and antibody to herpes simplex virus type 2 (HSV-2). By stepwise logistic regression analysis, associations persisted with race, age, hepatitis B markers, and HSV-2. Thus, the strong association of HTLV with hepatitis B, a marker for injection behavior, and the independent association with HSV-2 infection, a sexually transmitted pathogen, suggest similarities in the epidemiology of HTLV and human immunodeficiency virus infections in IVDUs.     

Effectiveness of HIV interventions among women drug users

A prospective cohort study was conducted among chronic injecting and crack cocaine drug using women. The hypothesis tested was that participation in a standard-plus-innovative intervention was more likely to produce behavior change than participation in a standard intervention. Standardized intervention protocols and corresponding instruments were designed. Data were collected on drug and sex risk behaviors at baseline and six-month follow-up intervals. The level of behavioral change in two intervention arms--standard and a standard-plus-innovative intervention--was measured by composite sex risk and drug risk scores using the generalized estimating equation approach. The results show that on four risk measures the enhanced intervention was significantly associated with positive change in both drug use and sexual behavior: less frequent drug use, less drug use during sex, and more frequent condom use during particular frequencies for specific types of sexual activities. Public health interventions are effective when targeting specific risk behaviors through interventions tailored to prevent HIV and reduce risk behaviors among specific cultural and gender groups.     

Critical issues regarding AIDS among injecting drug users

The paper identifies and reviews some critical issues in the field of human immunodeficiency virus (HIV) transmission among intravenous drug users. First, it discusses political denial and compartmentalization of the problem, giving an example from the United States that illustrates the lack of a coherent national strategy. It then reviews the role that stereotypes play in policy-making and points out that behaviour change can be considerable, giving details of successful safer injection programmes. The conditions that foster injection as a mode of ingesting drugs are reviewed, as in the role of drug trans-shipment patterns, particularly as a possible conduit of HIV. Finally, the role of prisons as places for the spread of HIV, and therefore for its prevention, is discussed.     

HIV infection among drug users: Future directions.

Explores the complexity and diversity of the different populations affected by the AIDS epidemic and the challenges presented to researchers and clinicians who design intervention strategies. Because HIV transmission occurs through high-risk behaviors, programs designed to modify behaviors to prevent the further spread of the virus are of paramount importance. In an attempt to address some of the unique needs of high-risk populations, specific groups are considered, including women, adolescents, the mentally ill, drug users, and homeless individuals. The successful reduction of prevention of HIV transmission hinges on tailoring messages to target populations in a meaningful manner that takes into account the unique needs of those who are at risk. (PsycINFO Database Record (c) 2010 APA, all rights reserved)