Effect of metabolic abnormalities on cognitive performance and clinical symptoms in schizophrenia

Abstract

SummaryAim. The objective of this study is to determine whether and how metabolic abnormalities are associated with clinical symptoms and cognitive performance in schizophrenia. Methods. 46 adult patients with schizophrenia taking first-or second generation antipsychotics were included in the study. The following data were collected: BMI, abdominal circumference, lipid panel and blood glucose, blood pressure and treatment of comorbidities. Clinical symptoms were assessed using PANSS, CDSS, CGI and SAS scales. Cognitive performance was assessed using CNS Vital Signs computerized battery of tests: Verbal Memory test, Visual Memory test, Finger Tapping Test, Symbol Digit Coding, Stroop Test, Shifting Attention Test, and Continuous Performance Test. Results. Dyslipidemia, raised LDL and raised blood glucose levels were the best predictors of more severe clinical symptoms (PANSS, PANSS P, PANSS G, CGI) and lower neurocognitive index, worse cognitive flexibility, executive functions, complex attention composite memory, verbal memory, slower reaction time and worse performance in SAT, CPT, ST tests. Obesity was associated with worse results in VBM, VIM, FTT, SDC tests. Raised blood pressure was associated with improvements in all cognitive domains and better performance in SAT, CPT, ST tests. Discussion. There are several weak associations between severity of clinical symptoms and metabolic abnormalities. Most of these were for blood glucose levels and raised blood glucose. Lipids and glucose abnormalities are the best predictors of deteriorated cognitive performance. Contrary to previous observations, raised blood pressure was associated with better results in cognitive tests. Conclusions. These findings indicate that cognitive impairment and metabolic abnormalities may be linked in patients with schizophrenia.

Associated illness severity in schizophrenia and diabetes mellitus: A systematic review

“…Four studies (Saatcioglu et al, 2016, Sicras-Mainar et al, 2015, Wysokinski, 2013, Pelayo-Teran, 2011 analysing this definition yielded results that show an association between dysglycaemia and schizophrenia symptom severity. Conversely, three studies reported no association between symptom severity and glycaemia, and whilst two of these were of relatively small sample size (Chen et al, 2013, Ogawa et al, 2011, the other featured a relatively larger sample size (Chen et al, 2014).…”

“…Overall, eleven studies (Wysokinski, 2013, Takayanagi et al, 2012, Saatcioglu et al, 2016, Sicras-Mainar et al, 2015, Chen et al, 2013, Chen et al, 2014, Ogawa et al, 2011, de Nijs et al, 2016, Dickinson et al, 2008, Gonzalez, 2015, Pelayo-Teran, 2011 were selected for detailed analysis. Tables 1, 2 and 3 demonstrate a comparison of the included studies.…”

“…Five studies used PANSS solely. Two studies (Wysokinski, 2013, Gonzalez, 2015 used PANSS in combination with various other measures including, the Calgary Depression Scale for Schizophrenia (CDSS), Clinical Global Impressions scale (CGI) , Marder factor and Negative Symptoms Assessment for Motivation scale (NSA). One study (Saatcioglu et al, 2016) used the Brief Psychiatric Rating Scale (BPRS), Scale for the Assessment of Positive and Negative Symptoms (SAPS/SANS), CDSS and Personal and Social Performance Scale (PSP).…”

“…One study (Wysokinski, 2013) employed ICD-10 criteria for paranoid schizophrenia only and one (Ogawa et al, 2011) did not specify what criterion was used but that participants did have a medical diagnosis of schizophrenia. All other studies utilised DSM-IV criteria for schizophrenia.…”

“…One other study (Wysokinski, 2013) returned mixed results, finding total PANSS scores related to severity of glycaemia (OR=1.03 (no SD provided) p=0.002), particularly positive symptoms (OR=1.14 (no SD provided) p=0.01) and also found that CGI scores were negatively associated with glucose abnormalities (OR=0.61 (no SD provided) p=0.04) but that negative symptoms were negatively associated with MS (OR=0.92 (no SD provided) p=0.01). Three studies, (Ogawa et al, 2011) (p=0.60), (Chen et al, 2013) (p>0.05) and (Chen et al, 2014) (t=0.11 p=0.12) found no significant correlation between glycaemia and symptom severity.…”