title: Injecting Drug Users Retention in Needle-Exchange Program and its Determinants in Iran Prisons.
abstract: BACKGROUND
  Participation and to stay in a health program depends on many factors. One of these programs is Needle Exchange Program (NEP) in prisons.
  
  
  OBJECTIVE
  The current study aimed to evaluate the retention of injecting drug prisoners and find the related factors in Iran.
  
  
  METHODS
  This cohort study analyzed data about injecting drug male prisoners who were participated in NEP in three Iranian prisons. Data was collected from October 2009 to June 2010. A proper approach of survival analyses including Kaplan-Meier method, Log-Rank test, and Cox Proportional Hazard Model were used to evaluate Injecting Drug Users (IDUs) retention in NEP and its determinants.
  
  
  RESULTS
  Out of 320 prisoners, 167 were from Isfahan Central Prison, 82 from Tehran-Ghezel-Hesar Prison, and 71 from Hamadan Central Prison. Two-hundred and fifty prisoners (78.4%) had history of drug injection; and drug injection was the most common choice for 115 persons (35.9%). Participants were followed up for 29 weeks, the mean (SD) time of retention in the program was 24.1 (0.6) weeks. There was a significant relationship between age, number of used needles per week, duration of addiction, age of addiction onset, as well as imprisonment age, main method of drug use, type of main using drug, Hepatitis B Virus (HBV) infection, job status, reason of arrestment, history of involvement in harm reduction programs, and the length of retention (P < 0.05). There was also significant relationship between the history of using harm reduction services (P = 0.007), tattooing (P = 0.01), longer durations of addiction (P = 0.048), and retention.
  
  
  CONCLUSIONS
  Tattooing and longer duration of addiction were two important factors that significantly increased retention in the program. In contrast, history of using harm reduction services was the factor that decreased persistence. The risk of quitting the program may decrease about 68% in those who did not involve in harm reduction programs.
authors.affiliation: United Nations Development Program, Prisons Organization, Tehran, IR Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Shahbazi
authors.affiliation: Health and Treatment Office of Iranian Prisons Organization, Tehran, IR Iran.
authors.forename: Marzieh
authors.initials: M
authors.lastname: Farnia
authors.affiliation: Social Determinant of Health Research Center, Kurdistan University of Medical Sciences, Sanandaj, IR Iran ; Epidemiology and Biostatistics Department, Faculty of Medicine, Kurdistan University of Medical Sciences, Sanandaj, IR Iran.
authors.forename: Ghobad
authors.initials: G
authors.lastname: Moradi
authors.affiliation: Department of Surgery, Tehran University of Medical Sciences, Tehran, IR Iran.
authors.forename: Mohammadreza
authors.initials: M
authors.lastname: Karamati
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health , International Campus, Tehran University of Medical Sciences, Tehran, IR Iran.
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Paknazar
authors.affiliation: Research Center for Social Determinants of Health, Semnan University of Medical Sciences, Semnan, IR Iran ; Community Medicine Department, Faculty of Medicine, Semnan University of Medical Sciences, Semnan, IR Iran.
authors.forename: Majid
authors.initials: M
authors.lastname: Mirmohammad Khani
keywords: Iran; Needle-Exchange Program; Prisons