Study on the Correlation Between Iris Characteristics and Schizophrenia

Abstract

Background Recently, researchers have conducted many studies on the potential contribution of the retina and other eye structures on schizophrenia. This study aimed to evaluate differences in iris characteristics between patients with schizophrenia and healthy individuals so as to find more easily accessible and easily measurable biomarkers with a view to improving clinical assessments and furthering our understanding of the disease. Methods Overall, 80 patients with schizophrenia and 52 healthy individuals were included in the case group and the control group, respectively. Iris images were collected from all subjects to compare differences in the structure and color of the iris. The Positive and Negative Symptom Scale (PANSS) and the Modified Overt Aggression Scale (MOAS) were used to evaluate the clinical symptoms and characteristics of 45 first-episode untreated schizophrenics, and analyzed correlations between iris characteristics and schizophrenia symptoms. Results There were significant differences in iris crypts ( P <0.05) and pigment spots ( P <0.01) between the case and control group, but no significant difference was found in iris wrinkles ( P <0.05). The logistic regression analysis demonstrated that the total iris crypts [odds ratio (OR) 1.166, 95% confidence interval (CI) 1.022–1.330] and total iris pigment spots (OR 1.815, 95% CI 1.186–2.775) increased the risk of suffering from schizophrenia. Furthermore, it was demonstrated that the number of iris crypts was positively associated with the MOAS score (r=0.474, P <0.01). Moreover, the number of the iris pigment spots (r=0.395, P <0.01) and wrinkles (r=0.309, P <0.05) were positively correlated with the subjects’ negative symptom scores, respectively. Conclusion Iris crypts and pigment spots were identified as potential biomarkers for detecting schizophrenia. In patients with first-episode untreated schizophrenia, iris characteristics may help psychiatrists to identify the illness and its severity, and to detect characteristic clinical symptoms.

Multi-ancestry Whole-exome Sequencing Study of Alcohol Use Disorder in Two Cohorts

“…OCA2 is not just a primary pigmentation gene influencing the amount and characteristics of melanin in melanocytes, but it also stands as an independent factor impacting eye color 51 . Studies have shown that OCA2 could be related to both eye color and neurodevelopmental disorders [52][53][54] . These genes could be novel targets for further functional studies for AUD.…”

Dispositional mindfulness and BIS/BAS up-close: can the self-regulation of people be seen in the eyes?

“…There were no foreseeable intended or unintended adverse effects on the participants. The standard procedure described in several other published studies was used ( Larsson et al, 2007 ; Edwards et al, 2016 ; Tian et al, 2022 ) without the supervision of an ophthalmologist. Participants made no complaints about difficulties caused by photographing their eyes.…”

“…Other specific iris structures, e.g., Fuchs’ crypts, pigment spots, and Wolfflin nodules, have been significantly associated with temperamental personality traits ( Larsson et al, 2007 ), Down syndrome ( Postolache and Parsa, 2018 ) or schizophrenia ( Trixler and Tényi, 2017 ; Tian et al, 2022 ). No study has explored DM, the behavioral inhibition system (BIS), and the behavioral approach system (BAS) regarding the iris structures.…”

“…These brain areas are considered important to personality and iris structures. Specific iris structures are related to personality traits ( Larsson et al, 2007 ), Down syndrome ( Postolache and Parsa, 2018 ), or mental disorders ( Trixler and Tényi, 2017 ; Tian et al, 2022 ).…”

“…Spotted pigmentation occurs even in flowers within self-organizing activator-inhibitor systems caused by specific proteins ( Ding et al, 2020 ). In humans, mental conditions such as schizophrenia, which is characterized by severe cognitive impairment and emotional dysregulation, and low level of mindfulness ( Tabak et al, 2015 ), are related to a higher level of pigment spots in the eyes ( Trixler and Tényi, 2017 ; Tian et al, 2022 ). There are also indications that the same genetic system influences neuronal development and iris formation ( Larsson et al, 2011 ).…”