اختلال شخصیت در داخل و خارج از طیف اسکیزوفرنی

Abstract The concept of schizotypal personality disorder has been heavily discussed since its introduction into the official classification of mental disorders in DSM-III. The aim of this study was to investigate the difference between schizotypal personality disorder within and outside the genetic spectrum of schizophrenia. Schizotypals with and without schizophrenic cotwins and first-degree relatives were compared, with individuals with other mental disorders and no mental disorders as controls. It appeared that only inadequate rapport and odd communication were more pronounced among schizotypals within, compared to schizotypals outside the schizophrenic spectrum. Schizotypals outside the schizophrenic spectrum, however, scored higher than schizotypals inside the schizophrenic spectrum on ideas of reference, suspiciousness, paranoia, social anxiety, self-damaging acts, chronic anger, free-floating anxiety and sensitivity to rejection. Interestingly, the four last features are seldom observed among schizotypals inside the schizophrenic spectrum. Monozygotic non-schizophrenic cotwins of schizophrenics score high on inadequate rapport, odd communication, social isolation and delusions/hallucinations. Monozygotic non-schizophrenic cotwins of schizotypals outside the schizophrenic genetic spectrum score high on illusions, depersonalization, derealization and magical thinking. Negative schizotypal features appear to be inside the schizophrenic spectrum, while positive borderline-like features are outside having another genetic endowment.

2. Results Table 1 presents the differences between the four groups on schizotypal and borderline features measured by SIB (SSP and SBP) and converted to standard scores. Table 1 shows that the schizotypals from schizophrenic families score higher than the controls (group 3 and/or group 4) on all schizotypal measures and on some borderline aspects (impulsivity/unpredictability, unstable relations, emptiness and identity disturbance). However, only on inadequate rapport and odd communication did they score higher than the schizotypals without schizophrenic relatives. Those with schizotypal personality disorder but without close schizophrenic biological relatives score higher on all schizotypal and borderline measures (except for elevation upon praise that in reality is not a borderline feature). They score in fact higher than the schizotypals that are relatives of schizophrenics on ideas of reference, suspiciousness/paranoid ideations, social anxiety/hypersensitivity to criticism, self-damaging acts, chronic anger/hostility, free-floating anxiety and sensitivity to rejection. As to the four last borderline features, those in the second group have a higher score than controls, while those in the first group (schizotypals in the schizophrenic families) do not score higher than controls. To sum up, all schizotypal features are found in both schizotypal groups. However, negative, eccentric schizotypy is more frequent in the first group and positive schizotypy in the second group. Furthermore, all borderline features are found in group 2, while only identity problems and instability are observed in group 1. Important to note is that the self-destructive aspects and the “neurotic” features: anger, anxiety and sensitivity to rejection are exclusively observed among the schizotypals outside the schizophrenic spectrum. Table 2 presents the SIB standard scores among the non-schizophrenic MZ, the DZ and the other first-degree relatives of schizophrenic index twins (group 1), of schizotypal index twins (group 2) and other index twins (group 3). (No schizophrenic individuals are present in the families of groups 2 and 3.) Table 2. Mean Standard scores on different schizotypal and borderline features among relatives of schizophrenics, schizotypals and controls (one-way analysis of variance) Relatives of schizophrenics Relatives of schizotypals Others MZ DZ First degree Total MZ DZ First degree Total MZ DZ First degree Total Illusions −0.51 −0.01 −0.20 −0.19 0.41 and −0.11 −0.06 −0.01 −0.25 −0.14 −0.13 0.18 Depersonalization/Derealization −0.20 −0.14 −0.22 −0.21 0.46 and −0.17 −0.01 0.04 −0.21 −0.33 −0.18 −0.24 Ideas of reference 0.30 −0.37 −0.22 −0.18 0.02 −0.41 −0.10 −0.14 −0.25 −0.20 −0.22 −0.22 Suspicious/Paranoid 0.12 −0.05 −0.14 −0.10 −0.10 −0.23 0.06 −0.03 −0.36 −0.32 −0.12 −0.25 Magical thinking 0.01 0.05 −0.24 −0.17 0.67b −0.22 0.19 and 0.17 and −0.19 −0.13 −0.12 −0.14 Inadequate rapport 0.63b 0.10b −0.11 −0.02b 0.08 0.19 −0.17 −0.08 −0.19 −0.31 −0.16 −0.22 Odd communication 1.04 and 0.24b 0.02b 0.14 and −0.34 −0.24 −0.21 −0.25 −0.27 −0.19 −0.23 −0.22 Social isolation 0.24b 0.04 −0.11 −0.06 −0.46 −0.03 0.12 0.00 −0.36 −0.23 −0.07 −0.21 Social anxiety/Vary of criticisms 0.29 −0.36 −0.19 −0.18 −0.43 −0.20 −0.13 −0.17 −0.19 −0.28 −0.13 −0.20 Delusions/Hallucinations 0.44b −0.24 −0.16 −0.13 −0.21 −0.31 −0.11 −0.16 −0.25 −0.17 −0.21 −0.20 Impulsivity/Unpredictability 0.06 0.31b −0.34 −0.20 −0.02 0.11 0.00 and 0.01b −0.15 −0.39 −0.25 −0.24 Self-damaging acts −0.16 0.04 −0.26 −0.21 0.05 0.08 −0.21 −0.12 −0.20 −0.21 −0.30 −0.24 Unstable relations 0.32 0.31b −0.30 −0.15 0.37 −0.33 0.03a 0.01 −0.19 −0.23 −0.19 −0.21 Compulsive sociability 0.23 0.01 −0.23 −0.16 0.02 0.22 0.09a 0.10 −0.04 −0.24 −0.07 −0.13 Affective instability −0.23 −0.22 −0.30 −0.28 −0.24 −0.33 −0.19 −0.23 −0.11 −0.14 −0.11 −0.13 Chronic anger/Hostility −0.04 −0.02 −0.17 −0.13 0.09 0.07 0.05 0.05 −0.20 −0.14 −0.03 −0.12 Emptiness/Boredom 0.26 −0.23 −0.26 −0.21 −0.14 −0.41 −0.14 −0.19 −0.10 −0.30 −0.19 −0.21 Free-floating anxiety −0.18 −0.50c −0.37 and −0.37 and −0.01 0.15 0.07 0.06 −0.09 −0.22 0.03 −0.08 Elevation upon praise −0.36 −0.25 −0.32b −0.31b 0.04 0.31 −0.25 −0.11 −0.14 0.02 −0.03 −0.02 Sensitivity to rejection 0.09 −0.27 0.00 −0.04 −0.42 −0.38 0.09 −0.08 −0.40 −0.25 0.04 −0.18 Identity disturbance 0.15 0.10b −0.30 −0.20 0.13 −0.25 0.05b 0.00b −0.28 −0.26 −0.13 −0.22 N 16 31 148 195 10 13 46 70 83 122 139 349 a Statistically significant p<0.05 different from relatives of schizophrenics, Bonferoni correction. b Statistically significant p<0.05 different from relatives of controls, Bonferoni correction. c Statistically significant p<0.05 different from relatives of schizotypals, Bonferoni correction. Table options Inadequate rapport, odd communication, social isolation and delusion/hallucination are common among the non-schizophrenic MZ cotwins of schizophrenics. If all the relatives are taken into account, free-floating anxiety and elevation upon praise are low compared to relatives of individuals with other psychiatric disorders. Illusions, depersonalization/derealization and magical thinking are common among the MZ relatives of those with schizotypal personality disorder. Compared to relatives of index twins with other psychiatric disorders, the total group of relatives is also higher on impulsivity/unpredictability and identity disturbance.