To the Editor.—
Storms et al (Archives 1982;39:323-327) stated that "Manowitz1 and Douglas and Booth2 found amino acid patterns of some schizophrenics that are similar to those of patients with celiac disease." That statement is potentially misleading, as Douglas and Booth studied only patients with celiac disease, not schizophrenics. Furthermore, Manowitz compared (1) the relative plasma amino acid levels of patients with celiac disease and controls as reported by Douglas and Booth with (2) relative plasma amino acid levels of schizophrenics and controls as reported by Perry et al3 in a study of patients with Huntington's chorea, schizophrenics, and controls.Storms et al were correct in stating that Manowitz reported significant positive correlations in amino acid levels for schizophrenics and patients with celiac disease from those separate sources. Unfortunately, Manowitz's analysis was flawed because he did not substantiate his correlation analysis by an analysis of the relevant scatter plots.
Simpson JC. Study of Gluten Effect in Schizophrenia. Arch Gen Psychiatry. 1983;40(3):345-346. doi:10.1001/archpsyc.1983.01790030115017