Comparision of neurological soft signs and minor physical anomalies in schizophrenia patients, psychotic symptomatic bipolar affective disorder I patients, their healthy siblings and healthy controls

SUMMARY Introduction and Aim: Schizophrenia and bipolar I disorder with psychotic features are chronic mental disorders that begin in young adult ages. While negative and cognitive symptoms may persist in schizophrenic patients, bipolar disorder have better functionality during the remission periods. Both disorders are transmitted highly genetically, and may exhibit different signs from the general population, such as delusions, hallucinations, neurological soft signs (NSS), and minor physical anomalies (MPA). Hallucinations, cognitive symptoms, minor physical anomalies, neurological soft signs are related to neuron migration in the second trimester and synaptic pruning mechanism in adolescent period. Both mechanisms support neurodevolepmental theory in psychosis. NSS and MPA are found more frequently in schizophrenia and bipolar affective disorder patients than in healthy people. Also NSS and MPA have been observed more frequent in the first degree relatives of schizophrenia and bipolar disorder patients than healthy controls. Subtypes of bipolar affective disorder are different from each other and some bipolar disorder patients don't have psychotic symptoms. Sibling studies may show genetic differences ore effective methodically than first-degree relatives' unselected studies. In this study, as far as we can see there are three basic unique directions; firstly we could not determine any study which compares NSS level and MPA frequency in schizophrenic patients, psychotic bipolar I disorder patients and their siblings with healthy controls. Secondly, no study was found comparing only psychotic bipolar I disorder group, their siblings and healthy controls in terms of NSS and MPA. Lastly, this study is leading research investigating whether pre-illness symptoms differed from healthy controls in schizophrenia siblings and in siblings of psychotic bipolar patients, after DSM 5 has been published (schizotypal personality disorder and prodrome schizophrenia were assessed by DSM 5 in schizophrenia spectrum disorders). In this study, we investigated; a) Whether psychotic symptomatic bipolar I disorder patients and schizophrenia patients differ in terms of MPA and NSS, b) Whether NSS and MPA are state / trait marker candidates for schizophrenia, c) Whether NSS and MPA are state / trait marker candidates for psychotic symptomatic bipolar I patients, d) Whether psychotic symptomatic bipolar siblings differ from schizophrenia siblings and healthy controls in terms of schizotypy Material and Method: 30 schizophrenic patients and 30 psychotic bipolar I disorder patients in clinical remission, 30 healthy schizophrenic siblings, 30 healthy psychotic bipolar I disorder siblings and 30 healthy controls were compared in terms of NSS and MPA. There were no statistically significant difference in all research groups in terms of age, gender, educational status. Neurological Evaluation Scale (NES) for NSS, Minor Physical Anomaly Scale (MPAS) for MPA, General Functional Assessment Scale (GAS) for functional level were used in all groups, Positive and Negative Symptom Rating Scale (PANSS) was used in schizophrenia patients, Young Mania Rate Scale (YMRS) was used in bipolar patients to measure the severity of disease and Magical Ideation Scale (MIS) was used to measure the level of magical thinking in healthy siblings of patients and the healthy control group. Findings and Results: Schizophrenia patients had lower NSS total score and NSS subscales than both schizophrenia siblings and healthy controls. Psychotic bipolar disorder patients had lower NSS total scores than both bipolar siblings and healthy controls in a similar way to schizophrenia. Motor coordination (MC), ordering of complex motor movements (OCMM) subscale scores were higher in schizophrenic patients than their siblings and healthy controls. Schizophrenic patients and psychotic bipolar disorder patients were not different from each other in terms of NSS subscale and total score. Low setting ear anomaly was different between schizophrenia patients, healthy siblings of schizophrenia, psychotic bipolar disorder patients, healthy siblings of bipolar disorder and healthy controls. Low setting ear anomaly was found to be more frequent in schizophrenia patients than in healthy siblings of schizophrenia patients and in healthy controls. Low setting ear anomaly frequency was similar in patients with psychotic bipolar disorder and patients with schizophrenia but healthy bipolar siblings did nor differ from healthy controls in terms of low setting ear anomaly. Healthy siblings of schizophrenic patients as well as healthy siblings of bipolar disorder patients were not different from each other and from healthy control group in terms of magical ideation scale scores. Discussion: Schizophrenia patients, performed poorly both on the NSS total score and on the subscales compared with schizophrenia siblings, and healthy controls. Psychotic bipolar disorder patients also showed poorer performance than both bipolar siblings and healthy controls, in a similar way to schizophrenia in terms of NSS. Motor coordination (MC), ordering of complex motor movements (OCMM) subscale scores were higher in schizophrenia patients than their siblings and healthy controls. MC and OCMM are thought to be state marker candidates indicating a feature specific to schizophrenia. Schizophrenic patients and psychotic bipolar disorder patients were not different from each other in terms of NSS subscale and total score. Therefore NSS total score is considered to be a typical trait marker candidate. Low setting ear anomaly was found to be more frequent in schizophrenia patients than in healthy siblings of schizophrenia patients and in healthy controls. Low setting ear anomaly frequency was similar in patients with psychotic bipolar disorder and patients with schizophrenia but healthy bipolar siblings did not differ from healthy controls in terms of low setting ear anomaly. The low setting ear anomaly appears to be a candidate marker for bipolar disorder and a trait marker candidate for schizophrenia. Schizophrenia siblings, bipolar siblings and healthy control group were found to have similar subthreshold impairment pattern in the magical ideation scale which was not at the psychotic level. This was thought to be affected by many similar religious and cultural concepts among the groups. Key words: schizophrenia, bipolar disorder, sibling, neurological soft sign, minor physical anomalies, low setting ear