White matter correlates of neuropsychological function in young adult methamphetamine users

dc.contributor.advisorJoska, John Aen_ZA
dc.contributor.advisorStein, Dan Jen_ZA
dc.contributor.authorFreeman, Carla Patriciaen_ZA
dc.date.accessioned2017-01-17T12:24:25Z
dc.date.available2017-01-17T12:24:25Z
dc.date.issued2016en_ZA
dc.description.abstractBackground: Methamphetamine (MA) abuse is a global health concern due to widespread use and harmful effects, which includes neurotoxicity. This study aimed to describe neurocognitive deficits associated with MA dependence in young adults and to explore whether these deficits correlate with white matter (WM) microstructural abnormalities using diffusion tensor imaging (DTI). Methods: Twenty-one MA dependent individuals recently enrolled in an outpatient rehabilitation program and nineteen healthy controls participated in the study. Each participant completed a neuropsychological evaluation and underwent diffusion tensor imaging within one week of testing. Average whole-brain fractional anisotropy (FA) and mean diffusion (MD) measures derived from DTI data were compared between groups. Group differences in performance within specific neurocognitive domains and in a composite global neurocognitive score (GNS) were tested using non-parametric univariate statistics and within a linear regression framework, adjusting for age and gender. Correlation analyses were conducted to test associations between the neuropsychological data and selected frontal white matter (WM) tracts, including the genu and body of the corpus callosum (CC); right and left cingulum bundle (CB); right and left uncinate fasciculus (UF); right and left anterior corona radiata (CR) and the right and left superior longitudinal fasciculus (SLF). Results: No significant between-group differences were detected for performance in any of the neuropsychological domains assessed. No relationship between FA or MD and the GNS was demonstrated in the tracts of interest. After adjusting for age and gender, significant group differences in FA and MD were detected across several regions of interest (ROI), however, these did not survive corrections for multiple comparisons. Conclusion: Cognitive performance and white matter integrity did not differ between young MA dependent subjects and healthy controls. Whatever differences that were found in white matter did not survive correction for multiple comparisons. These findings may reflect one or more of several possibilities: that brain function and structure is relatively preserved in younger individuals; or that differences were too small to be detected in this sample. Further studies should explore the effects of aging, poly-substance abuse and HIV coinfection on neurocognitive functioning and structural brain integrity in methamphetamine users.en_ZA
dc.identifier.apacitationFreeman, C. P. (2016). <i>White matter correlates of neuropsychological function in young adult methamphetamine users</i>. (Thesis). University of Cape Town ,Faculty of Health Sciences ,Division of Neuropsychiatry. Retrieved from http://hdl.handle.net/11427/22762en_ZA
dc.identifier.chicagocitationFreeman, Carla Patricia. <i>"White matter correlates of neuropsychological function in young adult methamphetamine users."</i> Thesis., University of Cape Town ,Faculty of Health Sciences ,Division of Neuropsychiatry, 2016. http://hdl.handle.net/11427/22762en_ZA
dc.identifier.citationFreeman, C. 2016. White matter correlates of neuropsychological function in young adult methamphetamine users. University of Cape Town.en_ZA
dc.identifier.ris TY - Thesis / Dissertation AU - Freeman, Carla Patricia AB - Background: Methamphetamine (MA) abuse is a global health concern due to widespread use and harmful effects, which includes neurotoxicity. This study aimed to describe neurocognitive deficits associated with MA dependence in young adults and to explore whether these deficits correlate with white matter (WM) microstructural abnormalities using diffusion tensor imaging (DTI). Methods: Twenty-one MA dependent individuals recently enrolled in an outpatient rehabilitation program and nineteen healthy controls participated in the study. Each participant completed a neuropsychological evaluation and underwent diffusion tensor imaging within one week of testing. Average whole-brain fractional anisotropy (FA) and mean diffusion (MD) measures derived from DTI data were compared between groups. Group differences in performance within specific neurocognitive domains and in a composite global neurocognitive score (GNS) were tested using non-parametric univariate statistics and within a linear regression framework, adjusting for age and gender. Correlation analyses were conducted to test associations between the neuropsychological data and selected frontal white matter (WM) tracts, including the genu and body of the corpus callosum (CC); right and left cingulum bundle (CB); right and left uncinate fasciculus (UF); right and left anterior corona radiata (CR) and the right and left superior longitudinal fasciculus (SLF). Results: No significant between-group differences were detected for performance in any of the neuropsychological domains assessed. No relationship between FA or MD and the GNS was demonstrated in the tracts of interest. After adjusting for age and gender, significant group differences in FA and MD were detected across several regions of interest (ROI), however, these did not survive corrections for multiple comparisons. Conclusion: Cognitive performance and white matter integrity did not differ between young MA dependent subjects and healthy controls. Whatever differences that were found in white matter did not survive correction for multiple comparisons. These findings may reflect one or more of several possibilities: that brain function and structure is relatively preserved in younger individuals; or that differences were too small to be detected in this sample. Further studies should explore the effects of aging, poly-substance abuse and HIV coinfection on neurocognitive functioning and structural brain integrity in methamphetamine users. DA - 2016 DB - OpenUCT DP - University of Cape Town LK - https://open.uct.ac.za PB - University of Cape Town PY - 2016 T1 - White matter correlates of neuropsychological function in young adult methamphetamine users TI - White matter correlates of neuropsychological function in young adult methamphetamine users UR - http://hdl.handle.net/11427/22762 ER - en_ZA
dc.identifier.urihttp://hdl.handle.net/11427/22762
dc.identifier.vancouvercitationFreeman CP. White matter correlates of neuropsychological function in young adult methamphetamine users. [Thesis]. University of Cape Town ,Faculty of Health Sciences ,Division of Neuropsychiatry, 2016 [cited yyyy month dd]. Available from: http://hdl.handle.net/11427/22762en_ZA
dc.language.isoengen_ZA
dc.publisher.departmentDivision of Neuropsychiatryen_ZA
dc.publisher.facultyFaculty of Health Sciencesen_ZA
dc.publisher.institutionUniversity of Cape Town
dc.subject.otherNeuropsychiatryen_ZA
dc.titleWhite matter correlates of neuropsychological function in young adult methamphetamine usersen_ZA
dc.typeMaster Thesis
dc.type.qualificationlevelMasters
dc.type.qualificationnameMPhilen_ZA
uct.type.filetypeText
uct.type.filetypeImage
uct.type.publicationResearchen_ZA
uct.type.resourceThesisen_ZA
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