Social Predictors for Transition into Injection Drug Use

描述（由申请人提供）：本前瞻性研究的目的是确定纽约市年轻成人非注射吸毒者（海洛因，快克/可卡因使用者）过渡到注射吸毒的危险因素。大量数据表明，注射吸毒是一种比非注射吸毒健康风险高得多的吸毒做法，主要原因是血液传播传染病、精神疾病合并症和其他社会后果。对非法药物使用的危险因素进行了研究；然而，关于过渡到注射做法的具体数据仍然很少。研究人员现在建议，确定社会环境（如社会网络和社会支持）对过渡到注射的影响，作为提高我们对注射药物使用和注射相关健康后果的认识的下一步。例如，虽然研究表明白人（根据一些研究，西班牙裔美国人）比黑人更有可能使用非法药物，而且开始使用的年龄更小，但与白人吸毒者相比，黑人和西班牙裔吸毒者更有可能承担更高的传染病发病率。这些种族/民族差异支持社会背景的研究，以及表征这种背景的因素如何随着时间的推移而变化（即从前过渡到过渡）。研究表明，社交网络是传播与健康有关的信息的可行方法，有助于这方面的研究产生更多的公共卫生影响。因此，更好地了解一个人的社会网络/支持可以导致针对社会网络的公共卫生战略。在本研究中，我们将确定社会网络/社会支持特征（如指数和网络成员的种族/民族，药物使用规范，网络规模/组成，以及经济，信息和情感支持）对以下方面的影响：1)过渡到注射，2)过渡年龄，3)过渡后早期性行为/药物风险行为。数据将来自：(1)一项前瞻性研究，对800名年龄在18-35岁的非注射吸毒者进行为期2年的随访；(2)对400名注射时间< 2年、年龄在18-35岁的新发静脉注射者进行横断面调查。该研究涉及纽约市吸毒者的目标和受访者驱动的抽样方法。基线调查和横断面调查将包括一项为期四年的社会行为审查，该审查将记录注射吸毒者过渡到注射前2-3年的情况，并与非注射吸毒者的相应日历期间进行比较。本研究将包括病例对照（新IDU病例/非IDU对照）、横断面（新IDU）和前瞻性（非IDU）设计分析。逻辑回归分析和边际模型将使用广义估计方程来解释个体内重复测量随时间的潜在类内相关性。

DESCRIPTION (provided by applicant): The purpose of this prospective study is to identify risk factors for transition into injection drug use among young adult non-injection drug users (heroin, crack/cocaine users) in New York City. Extensive data has shown that injection drug use is a substantially higher drug-using health risk practice than non-injection primarily due to transmission of blood-borne infectious disease, psychiatric co-morbidity, and other social consequences. Risk factors for illicit drug use have been studied; however, data specifically on transition into the practice of injection remain sparse. Researchers now suggest that determining the effects of the social environment such as social networks and social support on transition into injection as the next step in advancing our knowledge of both injection drug use and injection-related health consequences. For example, while research has shown whites (and according to some studies, Hispanics) as being more likely to use illicit drugs, and to begin use at a younger age than their black counterparts, black and Hispanic drug users are more likely to burden higher rates of infectious disease compared to white drug users. These racial/ethnic differences support the study of social context and how factors that characterize this context may change over time (i.e. from pre-transition to transition). Research has indicated social networks as a viable method of disseminating health-related information lending to additional public health impact resulting from this line of research. Thus, providing a better understanding of ones' social network/support can lead to public health strategies that target social networks. In this proposed study, we will determine the effect of social networks/social support characteristics (e.g. race/ethnicity of index and network members, drug use norms, network size/composition, and economic, informational and emotional support) on: 1) transition into injection, 2) age at transition, and 3) early sex/drug-risk behavior following transition. Data will be obtained from: (1) a prospective study with 2 years of follow-up among 800 non-IDUs, aged 18-35; and (2) a cross-sectional survey among 400 recent onset IDUs, injecting <=2 years, aged 18-35. The study involves targeted and respondent driven sampling methodology of drug users across NYC. The baseline and cross-sectional surveys will include a four-year sociobehavioral review that will capture 2-3 years prior to transition into injection among IDUs that can be compared to the corresponding calendar period in non-IDUs. This study will include analyses for case-control (new IDU cases/non-IDU controls), cross-sectional (new IDUs), and prospective (non-IDUs) designs. Logistic regression analyses and marginal models will be constructed using generalized estimating equations to account for potential intra-class correlation of repeated measures within an individual over time.