Changes in brain morphometry of leprosy patients under social stigma conditions.

Background: The stigma promotes social isolation and reinforces maladaptive behaviors, including major impacts on mental health. Leprosy is a curable infectious disease presenting damage in the skin and nerves. This study aims to investigate the neurobiological effects, through brain morphometry and behavioral changes in patients treated leprosy patients. Methods: The study sample consisted of a total of 14 previously treated leprosy patients (x ̅=42.1; SD=12.3) and 14 volunteer volunteers (x ̅= 40.5; SD=14.5) of the same age (p=0.38). High-resolution T1-weighted images were obtained using a 1.5 Tesla MRI scanner using FreeSurfer version 7.1.1 image processing software. Psychometric anxiety and negative affect scales were also completed by the volunteers, who were subsequently subjected to functional magnetic resonance imaging (fMRI). Results: Volumetric analysis of the amygdala in the group of patients (left: mean=1,684.94, SD=150.22; right: mean=1,716.42; SD=137.24) showed smaller volume (left: p=0.009; right: p=0.004) when compared to the control group (left: mean=1,832.68; SD=129.98; right: mean=1,845.49; SD=94.33). Regarding the psychometric scales, patients presented greater (p<0.01) anxiety symptoms (mean=6.77; SD=6.15) when compared to the control group (mean=2.00; SD=1.73) and also higher levels (p=0.05)  of negative affect (mean=17.08; SD=5.30) when compared to controls (mean=13.31; SD=3.77 ).Conclusion: The amygdala is a brain structure associated with defensive stimuli and it was also described in a previous study involving anxiety symptoms. Besides, anxiety is the second most common comorbidies reported by leprosy patients and its symptoms were higher for this group in the present results. The changes in brain morphometry and bahavior observed in present study may represent a cumulative neurobiological effect of their mental suffering in their social and stigmatizing leprosy-related condition.