|Primary Research Focus
||We sought to assess sexual risk behavior and neighborhood- level indicators of social and drug disorder exposure in a cohort of non-drug users (NDU) and drug users (CDU). We analyzed data from 415 participants enrolled in a 12 month study of genetics and environment on drug use trajec- tories. Participants completed the HIV Risk-taking Behavior Scale, Addiction Severity Index, and PhenX Drug Use Survey. Neighbor- hood risk was determined using the Neighborhood Inventory for Environmental Typology (NIfETy).