Clinical profile in schizophrenia and schizoaffective spectrum: relation with unconjugated bilirubin in a prospective and controlled study with psychopathological and psychosocial variables

Abstract

Objective. Our objective was to assess unconjugated bilirubin (UCB) as biomarker for schizophrenia (SCZ) and schizoaffective (SAF) spectrums disorder (relapse vs. partial remission). Methods. Eighty-eight psychotic patients completed first assessment during relapse at ward admission, half with SCZ and half with SAF disorder. Forty-four acute bipolar patients were used as controls. After 12-month follow-up, we collected longitudinal protocol (laboratory, psychopathological, and psychosocial data) from 60 patients, half with SCZ and half with SAF disorder. Results. During psychotic relapse (N = 88), we found a statistically significant difference (analysis of variance [ANOVA]; p = .002), confirmed after post hoc multiple comparisons (Bonferroni) between SCZ (N = 44) and both SAF (N = 44; p = .05) and bipolar controls (N = 44; p = .05); a positive correlation (Pearson’s r = .314) between UCB mean levels and Personal and Social Performance item (d) “disturbing and aggressive behaviors”; and a positive correlation (R2 = .223), with statistically significance (p = .008), between UCB mean levels and mean length of stay at the psychiatric ward in SAF patients who completed full protocol (N = 30). During partial remission (N = 60) we found: a statistically significant difference (ANOVA; p = .006), confirmed after post hoc multiple comparisons (Bonferroni) between SCZ (N = 30) and SAF (N = 30; p = .05); plus a negative correlation (Pearson’s r = −.399) between UCB mean levels and Positive and Negative Syndrome Scale item G7 “psychomotor retardation.” Comparing first and second assessments (paired samples t test) we found a statistically significant difference in UCB mean levels among SAF patients (p = .034). Conclusions. There is potential in the research of UCB as a biological marker for SCZ and SAF spectrums disorders during relapse and partial remission of both syndromes.

Bilirubin and inflammation in neurodegenerative and other neurological diseases

“…Patients with hyperbilirubinemia have shown significantly higher scores on the positive and general psychiatric subscales of the PANSS (Positive and Negative Syndrome Scale) [24] . In concordance with the previous finding, UCB elevation has been found frequently in psychotic episodes of schizophrenia [25,29] . Radhakrishnan et al [26] reported that UCB levels are higher in paranoid schizophrenia than non-paranoid schizophrenia.…”

Relation Between Unconjugated Bilirubin and Peripheral Biomarkers of Inflammation Derived From Complete Blood Counts in Patients With Acute Stage of Schizophrenia

“…A systematic review ( 25 ) showed that UCB is in part implicated in the pathophysiological process of schizophrenia, and elevated bilirubin may be linked with lower risk of schizophrenia in the acute stage. One recent study ( 46 ) showed potential of UCB as a biological marker for schizophrenia. Nevertheless, to our knowledge, the present study is the first to indicate that the combined effect of peripheral biomarkers of inflammation derived from CBC and UCB could be better diagnosis parameters compared with single predictor independently in patients with acute schizophrenia.…”

Aspects of Clinical Neuropsychology Related to the Psychotic Spectrum. A Comprehensive Systematic Review

“…In addition, the final outcome of the research [86], is focused on the clinical profile in schizophrenia and schizoaffective spectrum disorders, particularly in relation to unconjugated bilirubin. This prospective and controlled study examined the association with psychopathological and psychosocial variables.…”