The ongoing developments of psychiatric classification systems have largely improved reliability of diagnosis, including that of schizophrenia. However, with an unknown pathophysiology and lacking biomarkers, its validity still remains low, requiring further advancements. Research has helped establish multiple sclerosis (MS) as the central nervous system (CNS) disorder with an established pathophysiology, defined biomarkers and therefore good validity and significantly improved treatment options. Before proposing next steps in research that aim to improve the diagnostic process of schizophrenia, it is imperative to recognize its clinical heterogeneity. Indeed, individuals with schizophrenia show high interindividual variability in terms of symptomatic manifestation, response to treatment, course of illness and functional outcomes. There is also a multiplicity of risk factors that contribute to the development of schizophrenia. Moreover, accumulating evidence indicates that several dimensions of psychopathology and risk factors cross current diagnostic categorizations. Schizophrenia shares a number of similarities with MS, which is a demyelinating disease of the CNS. These similarities appear in the context of age of onset, geographical distribution, involvement of immune-inflammatory processes, neurocognitive impairment and various trajectories of illness course. This article provides a critical appraisal of diagnostic process in schizophrenia, taking into consideration advancements that have been made in the diagnosis and management of MS. Based on the comparison between the two disorders, key directions for studies that aim to improve diagnostic process in schizophrenia are formulated. All of them converge on the necessity to deconstruct the psychosis spectrum and adopt dimensional approaches with deep phenotyping to refine current diagnostic boundaries.

Schizophrenia is a multi-systemic disorder that is associated with lipid profile disturbances, altered glucose homeostasis and subclinical inflammation. It has been proposed that dysfunction of the gut-brain axis might underlie these alterations. Short-chain fatty acids (SCFAs) are considered to play a pivotal role in the gut-brain axis. In this study, we aimed to compare fecal levels of SCFAs in patients with schizophrenia and healthy controls (HCs), taking into consideration their relationship with common peripheral blood alterations observed in schizophrenia. The study included 100 stable outpatients with schizophrenia and 55 HCs. The levels of SCFAs (acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, isovaleric acid, and lactic acid) in fecal samples were measured. Also, lipid profile together with the levels of C-reactive protein, glucose and insulin were determined. The levels of isovaleric acid were significantly higher in patients with schizophrenia after co-varying for age, sex, and the adherence to the Mediterranean diet. Moreover, there were significant positive correlations of the levels of valeric acid, isovaleric acid and CRP in patients with schizophrenia. In this group of participants, higher levels of isovaleric acid were associated with significantly lower scores of delayed memory after adjustment for potential covariates and interactions with CRP levels. Our results indicate that individuals with schizophrenia show altered levels of isovaleric acid that might be associated with impairments of delayed memory. The association with cognitive impairments might be independent of interactions with immune-inflammatory processes. Longitudinal and experimental studies are needed to test causal mechanisms of observed correlations.

The aim of the study was the assessment of the level of stigmatisation of psychiatric patients and psychiatry as a field of study by students at medical schools in Poland and the comparison of students’ attitudes over the years. The study was conducted based on a proprietary questionnaire assessing the stage of tertiary education, sociodemographic status, and MICA-2 psychometric tool that is used for assessing both the attitudes of students at medical schools towards psychiatry as a field of study and patients with mental health disorders. According to the MICA score, those who have higher scores have more negative attitudes towards psychiatry. The survey consisted of two rounds at an interval of 3 years. Results. The first-round survey, conducted in 2017, involved 480 students. The second-round survey, conducted in 2020, involved 573 students. In both cases, women constituted the vast majority of respondents. Women, as well as medical major students, achieved significantly lower scores than men p < 0.001. The said relationship was also observed for individual experience with mental illness. There was no correlation between the MICA-2 total score and the psychiatry course completion—p = 0.105. However, the levels of stigmatisation are still high. The implementation of educational methods to improve the perception of psychiatric patients by students at medical schools should be taken into consideration. An increase in direct student–patient contact, for example, by means of intensive elective classes, could be beneficial.

Accumulating evidence indicates that individuals with schizophrenia show poor dietary habits that might account for increased susceptibility to cardiovascular diseases in this population. However, it remains unknown whether this observation can be generalized over the whole population of individuals with schizophrenia. Therefore, in this study we aimed to investigate dietary habits, in terms of adherence to the Mediterranean diet (MD) in subjects with the deficit subtype of schizophrenia (SCZ-D), those with non-deficit subtype (SCZ-ND), and healthy controls (HCs). We recruited 45 individuals with SCZ-ND, 40 individuals with SCZ-D, and 60 HCs. Dietary habits were assessed using the Food Frequency Questionnaire-6 with a 12-month recall. Adherence to MD was decreased only in subjects with SCZ-D compared with HCs. Lower adherence to MD was associated with significantly higher levels of clinician-rated and self-reported negative symptoms (including alogia, avolition, and anhedonia). No significant correlations of adherence to MD with depressive symptoms were found. Lower adherence to MD was related to significantly higher body mass index in subjects with schizophrenia, but not in HCs. Our results indicate that poor adherence to MD is associated with a diagnosis of SCZ-D, higher severity of negative symptoms, and greater risk of developing overweight or obesity.

Following spinal cord injury, muscles below the level of injury develop variable degrees of disuse atrophy. The present study assessed the physiological changes of the expiratory muscles in a cat model of spinal cord injury. Muscle fiber typing, cross-sectional area, muscle weight, and changes in pressure-generating capacity were assessed in five cats spinalized at the T₆level. Airway pressure (P)-generating capacity was monitored during lower thoracic spinal cord stimulation before and 6 mo after spinalization. These parameters were also assessed in five acute animals, which served as controls. In spinalized animals, P fell from 41 ± l to 28 ± 3 cmH₂O (means ± SE; P < 0.001). Muscle weight of the external oblique, internal oblique, transversus abdominis, and internal intercostal muscles decreased significantly ( P < 0.05 for each). Muscle weight of the external oblique, internal oblique, transversus abdominis, and internal intercostal, but not rectus abdominis (RA), correlated linearly with P ( r > 0.7 for each; P < 0.05 for each). Mean muscle fiber cross-sectional area of these muscles was significantly smaller ( P < 0.05 for each; except RA) and also correlated linearly with P ( r > 0.55 for each; P < 0.05 for each, except RA). In spinalized animals, the expiratory muscles demonstrated a significant increase in the population of fast muscle fibers. These results indicate that, following spinalization, 1) the expiratory muscles undergo significant atrophy and fiber-type transformation and 2) the P-generating capacity of the expiratory muscles falls significantly secondary to reductions in muscle mass.