People with schizophrenia with primary negative symptoms, known as deficit schizophrenia, had significantly wider oral palates compared with patients with nondeficit schizophrenia as well as control subjects in a study published online in Schizophrenia Bulletin.
“This difference in palate width may reflect a divergence in development between deficit and nondeficit patients that occurs by the early second trimester,” researchers wrote, “and is consistent with the hypothesis that deficit schizophrenia is a separate disease within the syndrome of schizophrenia.”
The findings come from an interdisciplinary collaboration of researchers, including lead author Brian Kirkpatrick, MD, chair of the department of psychiatry and behavioral sciences, University of Nevada Reno School of Medicine. A dentist made blinded measurements to compare palate shape in 21 people with deficit schizophrenia, 25 people with nondeficit schizophrenia, and 127 control subjects, all matched for age and gender.
While patients with deficit schizophrenia had palates that were significantly wider than those of participants in the comparison groups, researchers found no significant differences in the palates of patients with nondeficit schizophrenia compared with control subjects, and there were no significant differences between any groups in palate length or depth.
The authors propose several potential factors that could account for the developmental differences, including the greater prevalence of certain antibodies in people with deficit schizophrenia compared with people with nondeficit schizophrenia.
The findings “may point to one pathway to the development of schizophrenia with these negative symptoms that involves specific genes and exposure to a virus,” suggested study coauthor Gary Hack, DDS, of the University of Maryland School of Dentistry, Baltimore, MD.
“Our finding of physical orofacial differences in schizophrenia suggests that the whole-body model of this illness is not only more accurate,” said Dr. Hack, “but is a more appropriate model to present to patients, their family members, and students.”
Kirkpatrick B, Gürbüz Oflezer Ö, Delice Arslan M, Hack G, Fernandez-Egea E. An early developmental marker of deficit versus nondeficit schizophrenia [published online ahead of print August 19, 2019]. Schizophrenia Bulletin. 2019 August 19;[Epub ahead of print].
Bowen T. University of Nevada, Reno School of Medicine and University of Maryland School of Dentistry team find new evidence for physical differences in schizophrenia patients [press release]. Reno, Nevada: University of Nevada Reno, School of Medicine; October 7, 2019.