Transmural care for HIV-seropositive drug users: experiences from Southeast Limburg,the Netherlands

In 1999 the decision was taken to start a transmural consultation service for HIV-seropositive drug users at the Consultation Office for Alcohol and Drugs [Dutch acronym: CAD] in Heerlen, the Netherlands. This consultation service was run by an AIDS consultant from Maastricht University Hospital together with the addiction physician from the CAD. In the period 1 November 1998-30 April 2002 29 HIV-seropositive drug users made use of this consultation service. Highly active antiretroviral therapy was prescribed to 23 patients during an average of 21 months (range: 4-51). Eighteen patients responded well to this therapy (viral load < 50 copies/ml) after 12-24 weeks of treatment and thereafter during 21 months. Direct observed therapy (DOT) was applied to 16 patients. Therapeutic failure due to poor compliance was observed in 3 patients. Two of them had initially been successfully treated with medication whilst under supervision but the treatment failed when they became responsible for taking their own medication. It seems that involving the Consultation Office for Alcohol and Drugs in the treatment and DOT has a favourable effect on the treatment of HIV-positive drug users.     

Estimate of the number of HIV-infected intravenous drug users in Amsterdam]

By combining data collected through a cohort study among injecting drug users (IDUs), which started December 1985, with data on the number of notified cases of AIDS, the cumulative number of HIV-infected IDUs residing in Amsterdam was estimated. The estimated cumulative incidence of HIV-infection among IDUs in Amsterdam on 1 July 1991 was about 1050. By 1 July 1991 90 of these cases had been diagnosed with AIDS, while an estimated 150-200 cases died before AIDS had been diagnosed. The prevalence of IDUs residing in Amsterdam who were still alive and free of AIDS on 1 July 1991 was estimated to be about 750-800. Because of untimely deaths, only a limited number of these HIV-infected IDUs can be expected to be diagnosed with AIDS in the future. The prevalence on 1 July 1991 of HIV-infected IDUs being alive and free of (diagnosed) AIDS and living elsewhere in the Netherlands is estimated at about 500.     

Estimating the number of opiate users in amsterdam by capture-recapture: the importance of case definition

One of the objectives of Amsterdam's methadone maintenance treatment is maximising its coverage among problematic opiate users. In order to evaluate what proportion is reached, the capture–recapture method is conducted to estimate the prevalence of problematic opiate use. Samples of opiate users in contact with police, hospital or treatment are used. The treatment sample is limited to the low threshold treatment sample (treatment with minimal requirements to the clients). Based on differences of log likelihood ratio, Akaike's and Bayesian information criteria, log linear models are selected. The size of the population of problematic opiate users in 1997 is estimated to be 4130 (95% confidence interval: 3753–4566). Within 3 months 50% was registered: 16% at the police, 2.5% at the hospital and 40% at treatment. This study shows that the Amsterdam methadone treatment programs succeed in reaching a high proportion of problematic opiate users. The estimation of the prevalence of problematic opiate users is considered to be valid. However, if, instead of the low threshold treatment, the total treatment sample had been used, the population of interest and the sampled population would not match correctly, and prevalence would have been overestimated.     

我国15岁及以上注射吸毒HIV感染者确证后的生存分析

目的了解我国报告注射吸毒HIV感染者的死亡情况及危险因素, 为制定相关防治策略提供依据。方法资料来源于艾滋病综合防治信息系统注射吸毒HIV感染者, 采用回顾性队列研究方法进行分析, 计算死亡密度, 并采用Cox比例风险回归模型分析死亡的风险因素, 采用Excel 2019和SPSS 22.0软件进行数据整理和统计学分析。结果 2001-2020年, 我国累计报告≥15岁注射吸毒HIV感染者119 209例, 其中死亡59 094例, 全死因死亡密度为6.96/100人年, 艾滋病相关死亡密度为1.91/100人年, 总死亡密度呈下降趋势。多因素Cox比例风险回归模型分析结果显示, 注射吸毒HIV感染者全死因死亡风险, 相比于首次CD4+T淋巴细胞(CD4)计数>500个/μl者, 未检测CD4计数、0～、200～和350～个/μl的HR值(95%CI)分别为2.85(2.78～2.93)、2.47(2.40～2.54)、1.58(1.53～1.62)和1.24(1.21～1.28);相比于抗病毒治疗者, 未抗病毒治疗者的HR值(95%CI)为7.13(6.99～7.27);相比于...     

应用捕获-再捕获方法估计湖南省洪江区吸毒人数的调查

目的 估计湖南省洪江区吸毒人数。方法应用捕获-再捕获法对洪江区吸毒者人数进行估计，同时，应用最优分配随机分层抽样的方法验证。一种捕获-再捕获法(CR1法)以抽样调查调查人数为第一次捕获，以公安部门登记在册687人为再捕获。应用Seber调整公式，计算估计吸毒人员总人数。另一种(CR2法)采用戒毒所登记的记录，以4个月为间隔，前后两次为捕获-再捕获。最优分配随机分层抽样方法则采用访谈，获得数据。结果抽样调查共调查1388人，发现吸毒人员24人，占1．73％；洪江区总人口为72709人，估计总吸毒人数1258人。CR1法估计总吸毒人数904人；CR2法估计总吸毒人数1069人。三种估计数差别无统计学意义，但高于公安部门在册人数1．3～1．6倍。结论捕获-再捕获法可以满足对吸毒人数的估计。     

Estimates of the number of injecting drug users in a defined area

Abstract: Three estimates of the number of injecting drug users residing within the Eastern Sydney Area Health Service (ESAHS) were obtained by applying the capture-recapture technique to data from three reliable sources, specifically, Methadone Services, the Bourke Street Drug Advisory Service and the Albion Street Clinic. The obtained estimates were 3449, 3046 and 1103 respectively. Statewide methadone statistics were also used to obtain an estimate of 15 082 injecting drug users in New South Wales. This estimate was close to the linearly projected estimates (14 274 and 14 416) from two previous studies. Estimates based upon the methadone statistics indicate that approximately 23% of injecting drug users in New South Wales reside within the ESAHS. A sensitivity analysis was performed to assess the effects on the estimates of the likely violation of the closed population assumption.     

Estimating the number of HIV-infected injection drug users in Bangkok: a capture--recapture method.

OBJECTIVES. The purpose of the study was to estimate the number of injection drug users infected with the human immunodeficiency virus (HIV) in Bangkok to allow planning for health services for this population. METHODS. A two-sample capture-recapture method was used. The first capture listed all persons on methadone treatment for opiate addiction from April 17 through May 17, 1991, at 18 facilities in Bangkok. The second capture involved urine testing of persons held at 72 Bangkok police stations from June 3 through September 30, 1991. Persons whose urine tests were positive for opiate metabolites or methadone were included on the second list. RESULTS. The first capture comprised 4064 persons and the recapture 1540 persons. There were 171 persons included on both lists, yielding an estimate of 36,600 opiate users in Bangkok. Existing data indicate that 89% of opiate users in Bangkok inject drugs and that about one third are infected with HIV, yielding an estimate of approximately 12,000 HIV-infected injection drug users in Bangkok in 1991. CONCLUSIONS. During the 1990s the number of cases of acquired immunodeficiency syndrome (AIDS) and other HIV-related diseases, including tuberculosis, in the population of HIV-infected injection drug users in Bangkok will increase dramatically, placing new demands on existing health care facilities. The capture-recapture method may be useful in estimating difficult-to-count populations, including injection drug users.     

安徽省马鞍山市社区吸毒人群HIV、梅毒感染状况及其行为特征分析

目的了解马鞍山市社区吸毒人群艾滋病病毒（human immunodeficiency virus,HIV）、梅毒感染状况并分析该人群行为特征。方法采用方便抽样法抽取385名吸毒者,收集艾滋病相关行为及有关的信息,分析马鞍山社区吸毒人群的行为特征。血清学检测采用两次血清酶联免疫吸附试验（ELISA）的方法进行血清HIV抗体检测。采用快速血浆反应素环状卡片试验（简称RPR）的方法检测血清中梅毒抗体,以确定梅毒感染状况。结果 2008年4月～7月在马鞍山市共调查385名社区吸毒对象,HIV阳性感染率为0.78%;梅毒阳性感染率为6.75%。3名HIV阳性感染者均有共用注射器吸毒史,其中2名有非婚性行为,吸毒方式间差异有统计学意义（P〈0.05）;梅毒阳性的有26人,阳性感染者年龄主要集中在31～40岁。吸毒者自愿做HIV检测的相关因素回归分析显示,影响因素有与别人共用注射器、自愿去戒毒所戒毒、参加美沙酮维持治疗和接受艾滋病咨询服务、最近一次性交时使用安全套、最近一年与临时性伴发生性行为。结论建议在社区开展HIV、性传播疾病的咨询与检测,宣传教育是目前最为有效的防止艾滋病/性传播疾病在人群中传播的手段,同时开展有针对性的行为干预,以控制艾滋病等传染性疾病由高危人群向一般人群的传播。     

Identifying heterogeneity among injection drug users: a cluster analysis approach

Objectives. We used cluster analysis to subdivide a population of injection drug users and identify previously unknown behavioral heterogeneity within that population.Methods. We applied cluster analysis techniques to data collected in a cross-sectional survey of injection drug users in Winnipeg, Manitoba. The clustering variables we used were based on receptive syringe sharing, ethnicity, and types of drugs injected.Results. Seven clusters were identified for both male and female injection drug users. Some relationships previously revealed in our study setting, such as the known relationship between Talwin (pentazocine) and Ritalin (methylphenidate) use, injection in hotels, and hepatitis C virus prevalence, were confirmed through our cluster analysis approach. Also, relationships between drug use and infection risk not previously observed in our study setting were identified, an example being a cluster of female crystal methamphetamine users who exhibited high-risk behaviors but an absence or low prevalence of blood-borne pathogens.Conclusions. Cluster analysis was useful in both confirming relationships previously identified and identifying new ones relevant to public health research and interventions.Syringe sharing is a well-established mechanism for the spread of HIV and HCV.1^–3 The introduction of syringe exchange programs (SEPs) has had a substantial impact with respect to decreasing the attributable risk of infectious blood-borne pathogens such as HIV and HCV among injection drug users.4^–11 However, studies have shown variations in the effectiveness of SEPs,11^–18 in that syringe sharing behavior persists among some injection drug users.12^,18^–21Epidemiological studies in which contextual factors are used to explain syringe sharing (i.e., social network analyses22) have demonstrated that sharing behavior is not based exclusively on individual choice7^,23^–26; that is, factors other than syringe access may drive sharing among certain injection drug users.20^,26^–28 For example, syringe sharing has been demonstrated to be associated with dyadic relationships involving close friends or sexual partners12^,26^,29^,30 and partnerships in which injection drug users pool resources to obtain drugs or injection equipment.21^,24^,26^,31^,32 Thus, variation in sharing behaviors is explained by differences between high-risk groups.Some researchers suggest that designing interventions around variances seen between groups, and the context in which these variances reside, may be both efficient and efficacious,33^–38 especially in terms of public health practice. Understanding the heterogeneity in high-risk groups may be particularly relevant for those behaviors that persist despite the establishment of structural interventions such as SEPs.15^,18^–20^,28^,39^–44 Consequently, the use of nontraditional statistical methodologies (such as social network analysis) has been encouraged to capture this variance.33^,35 Cluster analysis,45^,46 “an exploratory technique that can be used to reveal unknown heterogeneity,”35^(p196) focuses on the inherent differences between cases rather than variables. It has been used in the HIV literature to develop typologies of behavior33^,37; however, its use is more widespread in the psychiatric and psychological literatures.38^,47^–50We used cluster analysis as an exploratory tool to investigate whether empirically derived clusters could help to explain heterogeneity in a sample of injection drug users. The broader applicability of this technique to public health investigations in general was also addressed.     

同伴推动抽样法在吸毒人群基数估计中的应用

目的 探索用同伴推动抽样法(respondent-driven sampling,RDS)结合乘数法进行吸毒人群基数估计的可行性.方法 2008年,采用RDS招募东莞市社区吸毒人群进行面对面的问卷调查,获得样本所占接触强制戒毒所和美沙酮维持治疗(methadone maintenance treatment,MMT)门诊的比例,用RDS分析软件进行权重处理;结合当地强制戒毒所和MMT门诊的数据,估计吸毒人群基数.结果 经过15周,共招募303名吸毒者.以强制戒毒所为基础,估计东莞市吸毒人群为52 028(90% CI:35 196～81 590)人,是在册登记数的2.67(90% CI:1.81～4.19)倍;估计注射吸毒人群43 651(90% CI:29 529～68 454)人,占常住成年人口数的0.87%(90% CI:0.59%～1.36%).以MMT门诊为基础,估计东莞市吸毒人群为7 058(90% CI:3 555～13 162)人.结论 RDS结合乘数法对吸毒人群进行基数估计是可行的;但基于MMT门诊数据的估计结果可能会被低估,在应用时应注意选择合适的接触机构以及接触时间.     

Screening for Hepatitis C in injecting drug users: a cost utility analysis

BACKGROUND: Hepatitis C is a major public health problem of increasing importance among injecting drug users, among whom screening has been proposed. We therefore estimated the cost utility of screening for hepatitis C infection among people with a history of injecting drug use in contact with drug misuse services. METHODS: A spreadsheet-based model of screening using ELISA followed by polymerase chain reaction tests and treatment using combination therapy with interferon alpha and ribavirin was developed. Parameters were informed by literature review, expert opinion and a survey of current screening practice in England. A range of one-way sensitivity analyses were carried out to explore uncertainty in the results for cost effectiveness. RESULTS: Screening for HCV is likely to yield benefits in the population concerned at around 28,000 pounds per quality adjusted life year. This estimate is reasonably stable when explored in extensive one-way sensitivity analysis but appeared sensitive to the proportion of HCV positive people who accept biopsy or treatment and the utility gains associated with successful drug treatment. Important other areas of uncertainty include the effects of mortality from other causes on the cost effectiveness of screening in this population and the time at which symptoms would have led to presentation in the absence of a screening programme. CONCLUSION: Screening for HCV in this population is moderately cost effective, although some caution must remain in accepting this estimate given the current uncertainties in this field, and further research is required.     

广西男性HIV阳性吸毒者配偶间传播回顾性研究

目的 了解广西男性HIV阳性吸毒者与其配偶间HIV传播及影响因素,为预防艾滋病经配偶间传播的防治策略提供科学依据.方法 对调查地区HIV阳性已婚吸毒男性的配偶进行问卷调查,收集人口学特征、艾滋病相关知识、吸毒及性行为等信息,并采血进行HIV、梅毒和生殖器疱疹病毒(HSV-2)抗体检测.结果 调查382名HIV阳性吸毒者男性的配偶,81.4％已知丈夫感染HIV.艾滋病知识知晓率为80.9％; 32.7％有吸毒行为,其中59.7％与丈夫共针吸毒;目前每月与丈夫性行为中,每次使用安全套比例为59.9％;被告知丈夫感染HIV的调查对象每月同房次数和从不使用安全套的频率均比告知前有所下降(P＜0.01).HIV、HSV-2、梅毒抗体阳性检出率分别为52.0％、57.5％、9.4％.结论 广西男性HIV阳性吸毒者的配偶HIV阳性率高,应加强该人群的干预,尽量早发现感染者并促使感染者主动及时告知配偶,以采取有效防治措施,减少艾滋病经配偶间传播.     

Effect of zinc and vitamin A supplementation on antibody responses to a pneumococcal conjugate vaccine in HIV-positive injection drug users: a randomized trial

HIV-infected individuals have impaired immune responses to vaccines and high rates of pneumococcal disease. The effect of vitamin A and zinc supplementation on the immunogenicity of a 7-valent pneumococcal CRM-197 conjugate vaccine (PC-7) was evaluated in 118 HIV+ injection drug users. Subjects were randomized to oral 400,000 IU vitamin A, 300 mg zinc, vitamin A + zinc, or placebo, then immunized. Geometric mean titer increased 1.3-3.3-fold for all pneumococcal serotypes. PC-7 elicited an immune response in HIV-infected adults but neither vitamin A nor zinc altered the immunogenicity of the evaluated vaccines.     

Prevalence of heroin and methamphetamine male users in the northern Taiwan, 1999–2002: capture-recapture estimates

Background  

Illegal drug use and related problems have been emerging as an important public health issue in Taiwan. Via the capture-recapture approach, the present study aimed to offer insights into the size of heroin and methamphetamine male user population in the northern Taiwan during the period from 1999 to 2002.     

Patterns of drug use among a sample of drug users and injecting drug users attending a General Practice in Iran

Aim  

This study aimed to examine drug use, drug treatment history and risk behaviour among a sample of Iranian drug users seeking treatment through a general practice clinic in Iran.