Minor physical anomalies and social cognition in patients with schizophrenia and their first degree relatives

Minor physical anomlalies (MPAs) are early dysmorphogenetic findings that can be frequently detected in both schizophrenia patients and their relatives, and deficits in social cognitive abilities have been shown in both groups. We aimed to investigate whether there is a relationship between MPAs and social cognition in both the patient group and the patient relatives.

Thirty-four schizophrenia patients in remission, 34 their first-degree relatives, and 34 healthy controls were included in the study. Participants were assessed for minor physical anomalies using the Minor Physical Anomalies Scale (MPAS), and for theory of mind using Reading the Mind in the Eyes Test (RMET) and Dokuz Eylül Theory of Mind Index (DEToMI).

Patients performed significantly worse than healthy controls on the DEToMI subtests 'first-order false belief', 'second-order false belief', 'faux pas' and 'DEToMI total' (p=0.003, p=0.001, p=0.016 and p=0.001, respectively). The mean scores of patients in RMET were significantly lower than those of patients' relatives and healthy controls (p=0.012 and p<0.001, respectively). Patients with mouth anomalies performed worse on the first-order false belief subtest than those without (p=0.029), and there was a negative correlation between mouth involvement and first-order false belief subtest performance in group I (r=-0.381; p=0.026). Patients with ear anomalies performed better on the irony/hinting subtest than those without (p=0.048), and there was a positive correlation between ear involvement and irony/hinting subtest performance in group I (r=0.364; p=0.034). Relatives of patients with mouth anomalies performed worse than those without on the second-order false belief subtest (p=0.043), and there was a negative correlation between mouth involvement and second-order false belief subtest performance in group II (r=-0.353; p=0.041). Apart from these significant findings, no significant association was found between DEToMI and RMET performances and MPAs in all groups.

The present study's findings considering the associations between minor physical anomalies and social cognition in schizophrenia patients and their first degree relatives would supply new perspectives in the clinicians' assessment of schizophrenia patients. Further research of this possible link with similar studies may be beneficial in better understanding the nature of the disease and in more comprehensive clinical evaluations of patients.