The effect of second-generation antipsychotics on anxiety/depression in patients with schizophrenia: A systematic review and meta-analysis.

OBJECTIVE: Despite the high prevalence of anxiety in schizophrenia, no established guideline exists for the management of these symptoms. We aimed to synthesize evidence on the effect of second-generation antipsychotics (SGAs) on anxiety in patients with schizophrenia. METHODS: We systematically searched Medline, Embase, PsycInfo, Web of Science, PubMed, and Cochrane library to identify randomized controlled trials of SGAs that reporting anxiety measures in schizophrenia. The search was limited to English-language articles published before February 2024. Data were pooled using a random-effects model. RESULTS: Among 48 eligible studies, 29 (n = 7712) were included in the meta-analyses comparing SGAs to placebo, haloperidol, or another SGAs for their effect on anxiety/depression. SGAs had a small effect on anxiety/depression versus placebo (SMD = -0.28 (95 % CI [-0.34, -0.21], p < .00001, I2 = 47 %, n = 5576)) associated with efficacy for positive (z = 5.679, p < .001) and negative symptoms (z = 4.490, p < .001). Furthermore, SGAs were superior to haloperidol (SMD = -0.44, 95 % CI [-0.75, -0.13], p = .005, n = 1068) with substantial study-level heterogeneity (I2 = 85 %). Excluding one study of quetiapine in first-episode patients (SMD = -3.05, n = 73), SGAs showed a small effect on anxiety/depression versus haloperidol without heterogeneity (SMD = -0.23, 95 % CI [-0.35, -0.12], p = 01; I2 = %0). Risperidone's effect on anxiety/depression was comparable to olanzapine (SMD = -0.02, 95 % CI [-0.24,0.20], p = .87, I2 = 45 %, n = 753) and amisulpride (SMD = 0.27, 95 % CI [-1.08,0.61], p = .13, I2 = 50 %, n = 315). CONCLUSION: While SGAs showed a small effect on anxiety/depression, the findings are inconclusive due to scarcity of research on comorbid anxiety in schizophrenia, heterogeneity of anxiety symptoms, and the scales used to measure anxiety. Further studies employing specific anxiety scales are required to explore antipsychotics, considering their receptor affinity and augmentation with serotonin/norepinephrine reuptake inhibitors or benzodiazepines for managing anxiety in schizophrenia.

Clozapine treatment and astrocyte activity in treatment resistant schizophrenia: A proton magnetic resonance spectroscopy study.

Clozapine is the only antipsychotic approved for treating treatment-resistant schizophrenia (TRS), characterized by persistent positive symptoms despite adequate antipsychotic treatment. Unfortunately, clozapine demonstrates clinical efficacy in only ~30-60 % of patients with TRS (clozapine-responders; ClzR+), while the remaining ~40-70 % are left with no pharmacological recourse for improvement (clozapine-resistant; ClzR-). Mechanism(s) underlying clozapine's superior efficacy remain unclear. However, in vitro evidence suggests clozapine may mitigate glutamatergic dysregulations observed in TRS, by modulating astrocyte activity in ClzR+, but not ClzR-. A factor that if proven correct, may help the assessment of treatment response and development of more effective antipsychotics. To explore the presence of clozapine-astrocyte interaction and clinical improvement, we used 3 T proton-magnetic resonance spectroscopy to quantify levels of myo-Inositol, surrogate biomarker of astrocyte activity, in regions related to schizophrenia neurobiology: Dorsal-anterior-cingulate-cortex (dACC), left-dorsolateral-prefrontal-cortex (left-DLPFC), and left-striatum (left-striatum) of 157 participants (ClzR- = 30; ClzR+ = 37; responders = 38; controls = 52). Clozapine treatment was assessed using clozapine to norclozapine plasma levels, 11-12 h after last clozapine dose. Measures for symptom severity (i.e., Positive and Negative Symptoms Scale) and cognition (i.e., Mini-Mental State Examination) were also recorded. Higher levels of myo-Inositol were observed in TRS groups versus responders and controls (dACC (p < 0.001); left-striatum (p = 0.036); left-DLPFC (p = 0.023)). In ClzR+, but not ClzR-, clozapine to norclozapine ratios were positively associated with myo-Inositol levels (dACC (p = 0.004); left-DLPFC (p < 0.001)), and lower positive symptom severity (p < 0.001). Our results support growing in vitro evidence of clozapine-astrocyte interaction in clozapine-responders. Further research may determine the viability of clozapine-astrocyte interactions as an early marker of clozapine response.

Evaluation of the Glymphatic System in Schizophrenia Spectrum Disorder Using Proton Magnetic Resonance Spectroscopy Measurement of Brain Macromolecule and Diffusion Tensor Image Analysis Along the Perivascular Space Index.

BACKGROUND AND HYPOTHESIS: The glymphatic system (GS), a brain waste clearance pathway, is disrupted in various neurodegenerative and vascular diseases. As schizophrenia shares clinical characteristics with these conditions, we hypothesized GS disruptions in patients with schizophrenia spectrum disorder (SCZ-SD), reflected in increased brain macromolecule (MM) and decreased diffusion-tensor-image-analysis along the perivascular space (DTI-ALPS) index. STUDY DESIGN: Forty-seven healthy controls (HCs) and 103 patients with SCZ-SD were studied. Data included 135 proton magnetic resonance spectroscopy (1H-MRS) sets, 96 DTI sets, with 79 participants contributing both. MM levels were quantified in the dorsal-anterior cingulate cortex (dACC), dorsolateral prefrontal cortex, and dorsal caudate (point resolved spectroscopy, echo-time = 35ms). Diffusivities in the projection and association fibers near the lateral ventricle were measured to calculate DTI-ALPS indices. General linear models were performed, adjusting for age, sex, and smoking. Correlation analyses examined relationships with age, illness duration, and symptoms severity. STUDY RESULTS: MM levels were not different between patients and HCs. However, left, right, and bilateral DTI-ALPS indices were lower in patients compared with HCs (P < .001). In HCs, age was positively correlated with dACC MM and negatively correlated with left, right, and bilateral DTI-ALPS indices (P < .001). In patients, illness duration was positively correlated with dACC MM and negatively correlated with the right DTI-ALPS index (P < .05). In the entire population, dACC MM and DTI-ALPS indices showed an inverse correlation (P < .01). CONCLUSIONS: Our results suggest potential disruptions in the GS of patients with SCZ-SD. Improving brain's waste clearance may offer a potential therapeutic approach for patients with SCZ-SD.

Cortical thinning in relation to impaired insight into illness in patients with treatment resistant schizophrenia.

Impaired insight into illness is a common element of schizophrenia that contributes to treatment nonadherence and negative clinical outcomes. Previous studies suggest that impaired insight may arise from brain abnormalities. However, interpretations of these findings are limited due to small sample sizes and inclusion of patients with a narrow range of illness severity and insight deficits. In a large sample of patients with schizophrenia, the majority of which were designated as treatment-resistant, we investigated the associations between impaired insight and cortical thickness and subcortical volumes. A total of 94 adult participants with a schizophrenia spectrum disorder were included. Fifty-six patients (60%) had treatment-resistant schizophrenia. The core domains of insight were assessed with the VAGUS insight into psychosis scale. We obtained 3T MRI T1-weighted images, which were analysed using CIVET and MAGeT-Brain. Whole-brain vertex-wise analyses revealed impaired insight, as measured by VAGUS average scores, was related to cortical thinning in left frontotemporoparietal regions. The same analysis in treatment-resistant patients showed thinning in the same regions, even after controlling for age, sex, illness severity, and chlorpromazine antipsychotic dose equivalents. No association was found in non-treatment-resistant patients. Region-of-interest analyses revealed impaired general illness awareness was associated with cortical thinning in the left supramarginal gyrus when controlling for covariates. Reduced right and left thalamic volumes were associated with VAGUS symptom attribution and awareness of negative consequences subscale scores, respectively, but not after correction for multiple testing. Our results suggest impaired insight into illness is related to cortical thinning in left frontotemporoparietal regions in patients with schizophrenia, particularly those with treatment resistance where insight deficits may be more chronic.

A measure of subjective substance use disorder awareness - Substance Use Awareness and Insight Scale (SAS).

INTRODUCTION: Impaired illness awareness or inability to recognize that one has a substance use disorder can be a barrier to treatment seeking and rehabilitation. A validated scale is needed to better understand the clinical impact of impaired substance use disorder awareness. This study aimed to examine the psychometric properties of the Substance Use Awareness and Insight Scale (SAS), a novel scale to assess impaired illness awareness in individuals with substance use disorder. METHODS: We developed the SAS, a 7-item self-report measure to assess the theoretical constructs of illness awareness in substance use disorder (www.illnessawarenessscales.com). Participants 18 years of age or older with a score of 8 or more on the Drug Use Disorders Identification Test (DUDIT) were included. Data were collected via Dynata, an online survey platform. RESULTS: A total of 299 participants were included (mean (SD) age = 47.3-years (15.4), 54% women). The SAS demonstrated good convergent (r = 0.82, p < 0.001) and discriminant validity (r = -0.23, p < 0.001) with a measure of illness recognition and positive affect, respectively. SAS also demonstrated good internal consistency (Cronbach's alpha = 0.86) and one-month test-retest reliability (intra-class correlation = 0.87). An exploratory factor analysis suggested the retention of two components. Separate analyses of the SAS in individuals with cannabis, opioid, and other substance use showed similar results. DISCUSSION: The results of this study provide initial support for the psychometric validation of the SAS in adults with substance use disorder. The SAS holds promise for use in research and clinical settings to assess the influence of impaired substance use disorder awareness on treatment outcomes.

A Measure of Illness Awareness in Individuals With Nicotine Dependence-Nicotine Use Awareness and Insight Scale.

INTRODUCTION: Impaired illness awareness or the inability to recognize that one has a dependence on nicotine may be a major barrier to seeking cessation treatment. To better understand the role of impaired illness awareness on treatment-seeking behavior and clinical outcomes, we developed and examined the psychometric properties of a novel scale measuring illness awareness in individuals with dependence on nicotine. AIMS AND METHODS: We developed the Nicotine Use Awareness and Insight Scale (NAS), a 7-item self-report measure to assess the theoretical construct of illness awareness in individuals with dependence on nicotine (www.illnessawarenessscales.com). Data from participants 18 years of age or older were collected via a web-based survey company, Dynata. Participants with moderate dependence on nicotine were included, defined by a score of four or more on the Fagerström Test for Cigarette Dependence (FTCD) or the FTCD adapted for electronic cigarettes (eFTCD). RESULTS: A total of 100 participants (mean [SD] age = 49.1 [16.1] years, 52% women) that met the inclusion criteria for either FTCD (n = 50) or eFTCD (n = 50) were included. The NAS demonstrated good convergent (r = .74, p < .001) and discriminant validity (r = .03, p = .786). It also demonstrated good internal consistency (Cronbach's alpha = 0.78) and one-month test-retest reliability (intra-class correlation = 0.86). An exploratory factor analysis yielded the retention of two components. CONCLUSIONS: The NAS is a novel scale to asses illness awareness in individuals with dependence on nicotine. This study provides initial support for the psychometric validity and reliability of NAS. IMPLICATIONS: The NAS may be used in research and clinical practice to evaluate the impact of impaired illness awareness on treatment-seeking behavior and clinical outcomes.