Plasma interleukin-6 and executive function in crack cocaine-dependent women

Abstract

AimThe aim of this study was to investigate the association between plasma interleukin 6 (IL-6) levels and executive function (EF) in crack cocaine-dependent women. Methods42 crack cocaine-dependent women (CRACK) and 52 healthy women (CONTROL) were evaluated with respect to EF using the Wisconsin Card Sorting Test (WCST). Plasma IL-6 levels were quantitatively determined using the multiplexed cytometric bead assay. ResultsThe CRACK group had poor performance on WSCT scores (Non-perseverative Errors and Percent Conceptual Level Responses) and higher plasma IL-6 levels when compared with the CONTROL group. Furthermore, IL-6 was correlated with worsening of several WCST sub-scores and a linear regression model showed that IL-6 levels predicted worse cognitive flexibility within the CRACK group independently of intelligence quotient and education. ConclusionsThe results of this study indicated that low performances in EF task are associated with higher IL-6 levels in crack cocaine-dependent women. These data bolster previous works that link the cognitive decline observed in drug addicts with mechanisms of inflammation.