Prevalence of cluster B personality disorders and related factors among clients attending methadone clinic at Muhimbili National Hospital

Abstract

Background: Co-morbidity between personality disorders and psychoactive substance use disorders is reported to be significantly high with serious negative implications on HIV prevalence and health services provision. Presence of this co-morbidity in clinical setting was noted to result into increased HIV related risks, and misconduct behaviours that interfere with treatment plans and hence poor clinical outcomes. Eventhough there are many studies reporting this co-morbidity and its negative impact with significant findings in western countries, there is scarcity of literature addressing this commorbidity in sub Saharan Africa. Objective: This study was aimed at assessing the prevalence of cluster B personality disorders and related factors (HIV related injecting and sexual risk behaviours and misconduct behaviours) among clients attending methadone clinic at Muhimbili National Hospital (MNH) in Dar-es –Salaam Tanzania. Materials and Methods: This was a hospital based cross-sectional analytical study that utilized a convenient sample of all recovering population of people who inject drugs attending methadone clinic at MNH during the time of data collection from October 2012 to January 2013. A structured interview schedule was used to collect socio-demographic particulars; participant‟s HIV risk behaviors, and rates of misconducts while Structured Clinical Interview for axis II personality disorders (SCID-II) was used to diagnose personality disorders. Captured data was entered, recorded and cleaned through computer software (SPSS version 18). Univariate data analysis was applied while Pearson Chi square (X2) and p-value (p < 0.05) statistical tests was used to assess the significant associations between outcome measures of interest and non-continuous factors assessed. Multivariate data analysis using backward logistic regression model for all the variables with p< 0.20 was applied to determine the strengths of associations of related factors of interest and cluster B personality disorder in order to adjust for confounders. Results: A total of 414 study participants were included in the analysis in which men comprised the majority 91.03% (n=378) of participants. The overall prevalence of cluster B personality disorder in this study population was found to be 77.4% (n=309) in which antisocial personality disorder was the most prevalent 34.60 % (n=143), followed by borderline personality disorder 30.80% (n=127), narcissistic personality disorder 30.40% (n=126), and the least prevalent was histrionic personality disorder that was found in 16.5% (n=68) of all study participants. The multivariate hierarchical logistic regression analysis revealed that participants with cluster B personality disorders were two and half more likely to be single than married (AOR 2.62, 95% CI: 1.27.-.5.39; p=0.01); four times more likely to be unemployed [AOR 4.02 (1.17-5.27) p=0.000]; two folds more likely to have sexual contacts with more than one partner in one day [AOR 2.24 (1.040-4.84) p= 0.039] almost twelve folds more likely to share syringes during drug injections [(AOR 11.86 (2.159-16.51) p =0.04], two and a half more likely to practice vijipoint [AOR 2.66(1.16-6.31) p= 0.002], three times more likely to be warned because of misbehaviour [AOR 3.112(1.35-7.19) p=0.001)], two times more likely to continue use of cannabis and heroin after stabilization dose [AOR 2.36(0.17-3.96) P=0.012], and [AOR 2.07(2.05-3.23) P= 0.009] and three times more likely to fail to restate back to work after treatment [AOR 3.203(1.14-5.73) p=0.023] as compared to participants without cluster B personality disorders. Conclusion and Recommendations: The overall prevalence of cluster B personality disorder in this study population was found to be very high and significantly associated with HIV risks (sexual and injection) behaviours as well as misconduct behaviours at the treatment setting. The findings of this study indicate a need for careful assessment of personality disorders in methadone programs for the purposes of additional interventions beyond drug treatment. Furthermore, it recommends research on the prevalence of all personality disorders among drug using and in general populations as well as on the causal relationship of personality disorder - substance abuse co-morbidity.