【作者】 胡翼飞；

【导师】 孙江平； 刘中夫；

【作者基本信息】 中国疾病预防控制中心 ， 流行病与卫生统计学， 2014， 博士

【摘要】 背景目前中国艾滋病流行呈经性途径传播为主的态势,近年来某些地区合成毒品使用泛滥。合成毒品滥用通过影响性行为,促进人类获得性免疫缺陷病毒(HIV)经性途径传播。目前国内尚缺少此类研究。目的1.了解人群中合成毒品使用者的行为特征与成瘾性。2.分析合成毒品滥用与感染HIV风险的关系。3.通过模型预测合成毒品使用对HIV传播的影响。方法1.通过横断面调查,以定性与定量相结合的方式,嵌入吸毒前后的行为学变化回顾,了解合成毒品使用者的行为学和血清学特征并使用自测量表评价成瘾性。2.在男性同性性行为人群(MSM)中开展病例对照研究,招募期内全部HIV阳性者为病例组,全部HIV阴性者做对照组,分析两组人群合成毒品使用的分布差异与HIV感染的关联,判断使用合成毒品对HIV经性传播的影响。3.通过调查获得的参数,以冰毒为例,采用传染病动力学SIS模型拟合合成毒品滥用的流行趋势及其对HIV流行的影响,模型拟合执法打击对合成毒品流行进程及合成毒品使用者中HIV传播的影响。结果本研究纳入调查对象896人,中位年龄27岁(18-69岁)。横断面研究纳入吸毒者679人,其中女性151人,男性528人,包括吸毒的MSM230人。病例对照研究纳入MSM447人,其中吸毒者230人,不吸毒者217人。MSM中HIV阳性者34例(7.6%),为病例组,其余413人为对照组。MSM中梅毒阳性者71例(15.9%)；异性性接触者(Heterosexual people,HSP)中男性HIV阳性者3例(1%),梅毒阳性者52例(17.5%)；女性未检出HIV阳性者,梅毒阳性者33例(21.4%)。使用合成毒品者吸毒后多报告性欲望上升、性快感增强、性活动时间延长、性伴数量增加、安全套使用率减少。女性初次吸毒的年龄为21岁,低于MSM(24岁)和HSP男性(25岁),初次使用2年后进入合成毒品规律使用阶段。男性吸毒主要为追求性刺激或增强性功能,女性为金钱财物。目前毒品滥用方式是口吸,未发现注射使用合成毒品者。合成毒品使用者成瘾比例超过40%。合成毒品使用者性伴网络呈现偶遇性、社交网络泛化的特征。调查对象最近半年内性伴网络规模为2.5士1.6(性伴数为0-5)。病例对照研究推断合成毒品使用是HIV感染的主要危险因素。合成毒品使用与多性伴相关,二者都与HIV感染相关。合成毒品对HIV感染的影响链条中,多性伴不是混杂因素。多元Logistic回归分析结果显示,合成毒品使用者感染HIV的风险是不使用者的3.2倍(95%CI:1.2-8.4),有固定性伴感染HIV的风险较无固定性伴者明显降低(OR=0.4,95%CI:0.1-0.9),曾有性病诊断史者更容易感染HIV(OR=2.8,95%CI:1.2-8.4),梅毒阳性者更容易感染HIV(OR=4.3,95%CI:1.8-10.4)。多元Logistic回归分析结果显示,Rush Poppers使用者感染HIV的风险是不使用者的3.9倍(95%CI:1.9-9.4),曾有性病诊断史者(OR=2.8,95%CI:1.2-6.2)和梅毒感染者(OR=4.6,95%CI:1.8-11.6)有更高的HIV感染风险。本研究构建的传染病动力学模型预测结果显示,目前在相对严厉的执法打击存在情况下(执法打击指数po=0.3),吸毒发生率由预测初年的1.9%上升到10年后的3.8%,而如果执法打击力度较弱的情况下(po=0.1),吸毒发生率由预测初年的1.9%上升到10年后的4.9%;吸毒流行率则分别由9%上升到20%(po=0.3)和9%上升到33%(po=0.1。最初10年内合成毒品使用者HIV的感染率分别由0.25%增至3.8%(po=0.3)和0.25%增至4.1%(po=0.1),流行将持续。如无其他防控措施,10年内单纯依靠执法打击,合成毒品使用者中HIV的感染率将会持续上升。结论研究发现HIV感染分别与任一合成毒品和Rush Poppers使用独立相关,控制HIV的传播需要考虑合成毒品流行的影响。合成毒品通过提高性活跃度、减少安全性行为、增加性伴数量、扩大社交网络,增加HIV经性传播的风险。调查显示合成毒品滥用已进入调查地区的HSP,提示合成毒品使用尚处于流行早期。模型拟合结果显示合成毒品使用对HIV的传播有影响；纳入执法打击指数的修正模型预测结果显示,单纯依靠执法打击岁会暂时性降低感染HIV的风险,但难以改变合成毒品滥用流行对吸毒者中HIV传播的长期进程。拟合过程及结果显示数学模型预测合成毒品使用对HIV传播的影响可行。更多还原

【Abstract】 BackgroundHIV epidemic in China presents sexual transmission as main route. Sythetic drug abuse is surging in some place in recent years. Synthetic drugs (SD) abuse fuels human acquired immunodeficiency virus (HIV) spreading via modifying sexual behaviors. The amount of abusers gradually increased over recent years due to users’perceptions of SD abuse’s low physical dependence.Objectives1. To understand the characteristic of SD abusers and appraise their addiction;2. To analysis potential HIV infection risk faced by SD abusers;3. To model and predict SD use’s impact on HIV transmission.Methods1. We use a mixed methodology to conduct a cross-sectional questionnaire survey combined with qualitative interview among SD abusers. Some participants were asked to recall behaviors’pattern in the last6months before and after riding on drugs. All the eligible participants were taken blood specimen for HIV and syphilis antibody test, as well self-administrated Severity of Dependence Scale.2. A unmatched case-control design was performed among men who have sex with men (MSM) who used drug ever or never to identify potential predictors for HIV infection. MSM who infected with HIV were treated as case group and HIV negative cases as control one. The uneven distribution of risk behaviors between two groups was used to evaluate the impact of SD use on HIV infection. Multi-variable unconditional logistic regression was performed to identify the predictors.3. The parameters from the survey, mainly on amphetamine use were used for dynamic model building to predict prevalence trends of SD use and its interaction with HIV epidemic, as well the impact of law enforcement on the epidemic course of SD use and HIV transmission. The infectious disease dynamic model-Susceptible-Infected-Susceptible (SIS) compartments was employed for the modelling design and building.ResultsA total of896eligible participants were enrolled, averagely aged27years with a range of18-69. Among them,679drug uses participated in cross-sectional study including151females and528males. Population based case-control study enrolled447MSM,230using drugs and217naive with drugs. Among MSM,34cases are HIV positive (7.6%) as case group, and the left413belongs to control group. For syphilis infection,71cases (15.9%) are positive among msm. While among heterosexual people(HSP),3males are HIV positive (1%) and52cases are syphilis positive (17.5%);33females (21.4%) are syphilis positive and no one infected with HIV.Most of participants reported an increasing of sexual desire, higher sexual pleasure, and prolonged sex activity but lower condom use rate on amphetamine type of stimulants(ATS) abuse. The median initial age for SD abuser was21for female, younger than25for heterosexual male and24for MSM. On average, the interval between initial use to regular abuse was2years. The motivation for the males riding on drugs was either for sexual pleasure or better sexual function, while the females’was for money or other incentives. The addiction rate among the participants exceeded40percent. No one reported SD abuse via injection and the administration way was oral use. Case-control study found synthetic drugs abuse are major risk factors for HIV infection among MSM. Having multiple sexual partners was excluded as one of confounding factors verified by sub-analysis. Both HIV infection and drug use associated with having multiple sexual partners. The size of sexual partners’network of the participants in the past6months are2.5±1.6(range:0～5).SD abusers were suffering more risk for HIV infection compared with non-user adjusted with other factors (aOR=3.2,95%CI:1.2-8.4). While the participants having a regular sexual partner were less likely for HIV infection (aOR=0.4,95%CI:0.1-0.9) and those having a history of STI diagnosis (aOR=2.8,95%CI:1.2-6.7) or being syphilis positive (aOR=4.3,95%CI:1.8-10.4) run more risk for HIV infection.After controlling other factors, the risk of HIV infection among Rush Poppers users is3.9times of the non-users’(95%CI:1.9-9.4). MSM having a history of STls’diagnosis (OR=2.8,95%CI:1.2-6.2) or being syphilis positive (OR=4.6,95%CI:1.8-11.6) were at higher odds to getting HIV infection.The modified SIS modeling results show the incidence rate of synthetic drugs abuse increase from1.9%in the initial year to3.8%by end of10years ahead in the comparatively stringent law enforcement environments (law enforcement index Po=0.3), while the incidence rate increases from to4.9%in loose law enforcement environment (Index Po=0.1). The prevalence of ATS use will increase from9%at present to20%(Index Po=0.1), while it will increase to33%(Index Po=0.3), and the rising trend will persist. HIV prevalence rate among drug abusers increases slowly at the beginning about0.3%and then rapidly reach3.8%at the end of year10th at Index Po=0.3or to4.1%at Index Po=0.1. And the trend rises upward continuously. We conclude HIV prevalence among SD abusers will persist and the trending prevalence won’t be changed relying on law enforcement intervention only though it might temperorily slow the HIV spreading.ConclusionsHIV infection was independently associated with any SD use and Rush Poppers use respectively among MSM. In future we need address the proliferation of SD use for containing the spread of HIV among MSM. As a matter of fact that methamphetamine abuse has entered general population, SD can facilitate HIV transmission via increasing uptake of risky sexual behavior and having more sexual partners. We cautiously conclude the SD use epidemic staged early in Q city by the hint that no one used SD via injection so far. Modeling results show it is difficult to control HIV transmission among the SD abusers relying only on law enforcement measures. A multi-pronged integrated-approaches response is needed.更多还原