Association Between Serum Anticholinergic Activity and Psychiatric Symptoms of Chronic Schizophrenia

Abstract

: The cholinergic system in schizophrenia has been associated with treatments, adverse effects, and pathophysiological processes. Although the role of the cholinergic system in schizophrenia has been thoroughly investigated, few studies have examined the dynamics of human cholinergic systems in vivo. We compared serum anticholinergic activity SAA in patients with schizophrenia to that in healthy controls and investigated correlations between anticholinergic activity and various domains of psychiatric symptoms. Fifteen chronically medicated patients with schizophrenia and 10 healthy controls participated in the study. We measured SAA using a receptor-binding assay 3 H -QNB . We also measured extrapyramidal motor symptoms and psychiatric symptoms, and assessed cognitive functioning with subscales of the Wechsler Memory Scale. Elevated levels of SAA 1.95 pmol / ml were signi cantly more common among patients with schizophrenia than among healthy controls P 0.001 . There was a signi cant negative correlation between SAA and extrapyramidal motor symptoms in patients with schizophrenia P 0.043 . We found no signi cant association between SAA and other psychiatric symptoms and cognitive functions. These results indicate that SAA is greater among patients with schizophrenia than healthy controls, and that the anticholinergic effects might reduce extrapyramidal motor symptoms but exacerbate thought disorders. Further studies are warranted to con rm this nding in a larger cohort of non-medicated patients.