Risk Model Assessment in Early-Onset and Adult-Onset Schizophrenia Using Neurological Soft Signs

Age at onset is one of the most important clinical features of schizophrenia that could indicate greater genetic loadings. Neurological soft signs (NSS) are considered as a potential endophenotype for schizophrenia. However, the association between NSS and different age-onset schizophrenia still remains unclear. We aimed to compare risk model in patients with early-onset schizophrenia (EOS) and adult-onset schizophrenia (AOS) with NSS. This study included 262 schizophrenia patients, 177 unaffected first-degree relatives and 243 healthy controls. We estimated the discriminant abilities of NSS models for early-onset schizophrenia (onset age < 20) and adult-onset schizophrenia (onset age ≥ 20) using three data mining methods: artificial neural networks (ANN), decision trees (DT) and logistic regression (LR). We then assessed the magnitude of NSS performance in EOS and AOS families. For the four NSS subscales, the NSS performance were greater in EOS and AOS families compared with healthy individuals. More interestingly, there were significant differences found between patients' families and control group in the four subscales of NSS. These findings support the potential for neurodevelopmental markers to be used as schizophrenia vulnerability indicators. The NSS models had higher discriminant abilities for EOS than for AOS. NSS were more accurate in distinguishing EOS patients from healthy controls compared to AOS patients. Our results support the neurodevelopmental hypothesis that EOS has poorer performance of NSS than AOS. Hence, poorer NSS performance may be imply trait-related NSS feature in EOS.

Improving risk assessment and familial aggregation of age at onset in schizophrenia using minor physical anomalies and craniofacial measures

Age at onset is the most important feature of schizophrenia that could indicate its origin. Minor physical anomalies (MPAs) characterize potential marker indices of disturbances in early neurodevelopment. However, the association between MPAs and age at onset of schizophrenia is still unclear. We aimed to compare risk assessment and familial aggregation in patients with early-onset schizophrenia (EOS) and adult-onset schizophrenia (AOS) with MPAs and craniofacial measures.We estimated the risk assessment of MPAs among patients with EOS (n = 68), patients with AOS (n = 183), nonpsychotic relatives (n = 147), and healthy controls (n = 241) using 3 data-mining algorithms. In addition, we assessed the magnitude of familial aggregation of MPAs with respect to the age at onset of schizophrenia.The performance of EOS was superior to that of AOS, with discrimination accuracies of 89% and 76%, respectively. Combined MPA scores as the risk assessment were significantly higher in all schizophrenia subgroups and the nonpsychotic relatives of EOS patients than in the healthy controls. The recurrence risk ratio for familial aggregation of the MPA scores of EOS families (odds ratio 9.27) was substantially higher than that of AOS families (odds ratio 2.47).The results highlight that EOS improves risk assessment and has a severe magnitude of familial aggregation of MPAs. These findings indicate that EOS might result from a stronger genetic susceptibility to neurodevelopmental deficits.

Morphological and Molecular Changes in the Cortex and Cerebellum of Immunocompetent Mice Infected with Zika Virus

Zika virus (ZIKV) disease continues to be a threat to public health, and it is estimated that millions of people have been infected and that there have been more cases of serious complications than those already reported. Despite many studies on the pathogenesis of ZIKV, several of the genes involved in the malformations associated with viral infection are still unknown. In this work, the morphological and molecular changes in the cortex and cerebellum of mice infected with ZIKV were evaluated. Neonatal BALB/c mice were inoculated with ZIKV intraperitoneally, and the respective controls were inoculated with a solution devoid of the virus. At day 10 postinoculation, the mice were euthanized to measure the expression of the markers involved in cortical and cerebellar neurodevelopment. The infected mice presented morphological changes accompanied by calcifications, as well as a decrease in most of the markers evaluated in the cortex and cerebellum. The modifications found could be predictive of astrocytosis, dendritic pathology, alterations in the regulation systems of neuronal excitation and inhibition, and premature maturation, conditions previously described in other models of ZIKV infection and microcephaly.

Oculomotor Abnormalities and Aberrant Neuro-Developmental Markers: Composite Endophenotype for Bipolar I Disorder: Anomalies Oculomotrices et Marqueurs Neuro-Développementaux Aberrants : Endophénotype Composite du Trouble Bipolaire I

BACKGROUND

Neurological soft signs (NSSs), minor physical anomalies (MPAs), and oculomotor abnormalities were plausible biomarkers in bipolar disorder (BD). However, specific impairments in these markers in patients after the first episode mania (FEM), in comparison with first-degree relatives (high risk [HR]) of BD and healthy subjects (health control [HC]) are sparse.

AIM OF THE STUDY

This study aimed at examining NSSs, MPAs, and oculomotor abnormalities in remitted adult subjects following FEM and HR subjects in comparison with matched healthy controls. Investigated when taken together, could serve as composite endophenotype for BD.

METHODS

NSSs, MPAs, and oculomotor abnormalities were evaluated in FEM (n = 31), HR (n = 31), and HC (n = 30) subjects, matched for age (years) (p = 0.44) and sex (p = 0.70) using neurological evaluation scale, Waldrop's physical anomaly scale and eye tracking (SPEM) and antisaccades (AS) paradigms, respectively.

RESULTS

Significant differences were found between groups on NSSs, MPAs, and oculomotor parameters. Abnormalities are higher in FEM subjects compared to HR and HC subjects. Using linear discriminant analysis, all 3 markers combined accurately classified 72% of the original 82 subjects (79·2% BD, 56·70% HR, and 82·1% HC subjects).

CONCLUSIONS

AS and SPEM could enhance the utility of NSSs, and MPAs as markers for BD. The presence of these abnormalities in FEM suggests their role in understanding the etiopathogenesis of BD in patients who are in the early course of illness. These have the potential to be composite endophenotypes and have further utility in early identification in BD.