Muscle Abnormalities in Acute Psychoses

Abstract

SERUM creatine phosphokinase (CPK) and aldolase activities are increased in many acutely psychotic patients of a variety of diagnostic types.^1-3 CPK exists in three molecular forms (isoenzymes). Type I is found almost exclusively in the brain, type II in cardiac muscle, and type III in skeletal and cardiac muscle.⁴ Much smaller amounts are present in many tissues.⁵ Only the type III isoenzyme of CPK was found in the sera of psychotic patients.^1,2 A number of possible causes of an increased activity in serum of type III CPK have been evaluated: orally or intramuscularly administered psychotropic medications^2,6; physical activity^2,7; severe emotional distress not part of a psychotic process² weight loss^2,8; hypersecretion of steroids² or epinephrine⁸; and muscle tension.⁷ These have been considered to be not responsible for the increased serum enzyme activity in most acutely psychotic patients. Increased activity of serum