Neuropathologic Features in Chronic Methamphetamine Use.

Methamphetamine is a psychostimulant that exerts its euphoric and stimulant effects by increasing cytosolic monoamine concentration at the nerve terminal. In addition to its known systemic cardiovascular effects, there is compelling evidence to suggest a direct neurotoxic effect of methamphetamine; however, the existing body of literature includes very few human tissue studies. This exploratory analysis used postmortem human brain specimens to examine histologic and immunohistochemical features associated with chronic methamphetamine use. This retrospective cohort study included 60 decedents who were autopsied at the University of Iowa Hospitals and Clinics between the years 2015 and 2021. Logistic regression models demonstrated no definite pathologic changes in the hippocampi of individuals with a history of chronic methamphetamine use. Decedents with a history of methamphetamine use had a marginally increased odds of basal ganglia arteriosclerosis, which did not reach statistical significance (odds ratio, 3.33; 95% confidence interval, 0.6-19.2; P = 0.17), which may be independent of the systemic hypertensive effects of methamphetamine. Future studies that include targeted examination of brain regions of interest, such as the basal ganglia and specifically the striatum, may prove revealing.