A multinational group of investigators found that VisDys were reported considerably more often by patients with recent-onset psychosis and CHR than by those with recent-onset depression or a group acting as healthy control participants.
In addition, vision problems of higher severity were associated with less functional remission both for patients at CHR and those with recent-onset psychosis. Among patients with CHR, VisDys was also linked to lower quality of life (QOL), higher depressiveness, and more severe impairment of visuospatial constructability.
The researchers used fMRI imaging to compare resting-state functional brain connectivity in participants with recent-onset psychosis, CHR, and recent-onset depression. They found that the occipital (ON) and frontoparietal (FPN) subnetworks were particularly implicated in VisDys.
“Subtle VisDys should be regarded as a frequent phenomenon across the psychosis spectrum, impinging negatively on patients’ current ability to function in several settings of their daily and social life, their QOL, and visuospatial abilities,” write investigators led by Johanna Schwarzer, Institute for Translational Psychiatry, University of Muenster (Germany).
“These large-sample study findings suggest that VisDys are clinically highly relevant not only in [recent-onset psychosis] but especially in CHR,” they stated.
The findings were published online in Neuropsychopharmacology.
Subtle, underrecognized
Unlike patients with nonpsychotic disorders, approximately 50%-60% of patients diagnosed with schizophrenia report VisDys involving brightness, motion, form, color perception, or distorted perception of their own face, the researchers reported.
These “subtle” VisDys are “often underrecognized during clinical examination, despite their clinical relevance related to suicidal ideation, cognitive impairment, or poorer treatment response,” they wrote.
Most research into these vision problems in patients with schizophrenia has focused on patients in which the illness is in a stable, chronic state – although VisDys often appear years before the diagnosis of a psychotic disorder.
Moreover, there has been little research into the neurobiological underpinnings of VisDys, specifically in early states of psychosis and/or in comparison to other disorders, such as depression.
The Personalised Prognostic Indicators for Early Psychosis Management (PRONIA) Consortium studied the psychophysiological phenomenon of VisDys in a large sample of adolescents and young adults. The sample consisted of three diagnostic groups: those with recent-onset psychosis, those with CHR, and those with recent-onset depression.
VisDys in daily life were measured using the Schizophrenia Proneness Instrument–Adult Scale (SPI-A), which assesses basic symptoms that indicate increased risk for psychosis.
Visual information processing
Resting-state imaging data on intrinsic brain networks were also assessed in the PRONIA sample and were analyzed across 12,720 functional connectivities between 160 regions of interest across the whole brain.
In particular, the researchers were interested in the primary networks involved in visual information processing, especially the dorsal visual stream, with further focus on the ON and FPN intrinsic subnetworks.
The ON was chosen because it comprises “primary visual processing pathways,” while the FPN is “widely suggested to modulate attention related to visual information processing at higher cognitive levels.”
The investigators used a machine-learning multivariate pattern analysis approach that “enables the consideration of multiple interactions within brain systems.”
The current study involved 721 participants from the PRONIA database, including 147 participants with recent-onset psychosis (mean age, 28.45 years; 60.5% men), 143 with CHR (mean age, 26.97 years; about 50% men), 151 with recent-onset depression (mean age, 29.13 years; 47% men), and 280 in the healthy-controls group (mean age, 28.54 years; 39.4% men).
The researchers selected 14 items to assess from the SPI-A that represented different aspects of VisDys. Severity was defined by the maximum frequency within the past 3 months – from 1 (never) to 6 (daily).
The 14 items were as follows: oversensitivity to light and/or certain visual perception objects, photopsia, micropsia/macropsia, near and tele-vision, metamorphopsia, changes in color vision, altered perception of a patient’s own face, pseudomovements of optic stimuli, diplopia or oblique vision, disturbances of the estimation of distances or sizes, disturbances of the perception of straight lines/contours, maintenance of optic stimuli “visual echoes,” partial seeing (including tubular vision), and captivation of attention by details of the visual field.
Participants also completed the Beck Depression Inventory–II scale (BDI-II), the Positive and Negative Syndrome Scale (PANSS), the Functional Remission in General Schizophrenia, and several other scales that measure global and social functioning.
Other assessments included QOL and the Rey-Osterrieth Complex Figure Test, which is a neuropsychological measurement of visuospatial constructability.