Serum creatine phosphokinase in schizophrenia.

The author notes that increased serum creatine phosphokinase (CPK) activity is found in the majority of hospitalized acutely disturbed schizophrenics and patients with affective psychoses. It is probable that some of these increases do not result from nonspecific factors such as activity, trauma, or stress, which do cause increases in some cases. Those patients who show increased CPK activity have more florid psychopathology and tend to have higher CPK levels in nonacute periods than those without increases. First-degree relatives of psychotic patients with elevated serum CPK have high-normal or slightly increased serum CPK. There is also evidence of other neuromuscular dysfunction in psychotic patients. The author concludes that the investigation of CPK may have considerable heuristic value for the study of schizophrenia and other psychoses.