Regional gray matter reduction correlates with subjective quality of life in schizophrenia
Introduction
Quality of life (QOL) is an important consideration for patients with schizophrenia (Hofer et al., 2005). QOL is defined as a person's sense of well-being, life satisfaction and health status (Lehman, 1997). Previous studies have investigated predictors of QOL in schizophrenia, and several studies reported sociodemographic factors, depressive mood, and psychiatric symptoms as important determinants for QOL (Jin et al., 2001; Hofer et al., 2005; Aki et al., 2008; Yamauchi et al., 2008; Narvaez et al., 2008).
Among the psychiatric symptoms, severity of both positive symptoms (Gaite et al., 2002; Ritsner, 2003; Thornicroft et al., 2004) and negative symptoms (Packer et al., 1997; Heslegrave et al., 1997; Aksaray et al., 2002) have been associated with worse QOL. Although, previous studies show some inconsistency, recent meta-analysis found weak but significant correlations between positive and negative symptom levels and QOL (Eack and Newhill, 2007).
Brain magnetic resonance imaging (MRI) studies have demonstrated multiregional gray matter (GM) reductions in patients with schizophrenia (Haijma et al., 2012; Suzuki et al., 2005). Voxel-based morphometry (VBM; Ashburner and Friston, 2000) is an automated imaging-analysis method for exploring regional GM alterations in the whole brain. Recent meta-analyses of VBM studies of patients with schizophrenia showed GM reductions in such regions as the medial prefrontal cortex (MPFC), dorsolateral prefrontal cortex (DLPFC), anterior cingulate cortex, superior temporal gyrus (STG), insula, parahippocampal gyrus, amygdala, thalamus, and striatum (Ellison-Wright et al., 2008; Glahn et al., 2008). Some of these regional GM alterations were found to be related to symptom severity in schizophrenia patients. For instance, a large sample VBM study (Koutsouleris et al., 2008) reported associations between the abnormalities in the perisylvian region and positive symptoms, and a meta-analysis (Bora et al., 2011) reported an association between the abnormalities in the medial frontal gyrus/orbitofrontal cortex and negative symptoms.
Thus, the previous studies suggest associations between QOL and symptoms, and between GM and symptoms. Our interest in this study was to explore the more detailed nature of the interrelationship among QOL, symptoms, and GM pathology, using VBM. We expected associations among some aspects of QOL, positive symptoms, and perisylvian GM pathology, and associations among other QOL aspects, negative symptoms, and prefrontal GM pathology.
Section snippets
Participants
The schizophrenia group comprised 45 patients (25 men and 20 women, 42 right-handed and 3 left-handed) who were referred to the Department of Neuropsychiatry, Kyoto University Hospital. Each patient fulfilled the criteria for schizophrenia based on the Structural Clinical Interview for DSM-IV (SCID). Psychopathology was assessed using the Positive and Negative Syndrome Scale (PANSS) (Kay et al., 1987). All patients were receiving antipsychotic medication (first-generation [n = 4],
Demographic and clinical data
Table 1 shows demographic and clinical information. The estimated VIQ and PIQ were significantly lower in patients with schizophrenia than in controls. However, there was no significant difference in demographics (age, gender, handedness, education level) between patients with schizophrenia and controls.
Correlational analysis
There were no significant correlations between the psychosocial subscale score of SQLS and demographic variables, i.e. age, gender, education, and estimated VIQ/PIQ, in the patient group.
Discussion
This is the first study, to our knowledge, to investigate the relationship between subjective QOL, symptoms and brain volume in patients with schizophrenia, using the VBM technique. Our study revealed that volume reductions in some cortical areas are correlated with lower QOL. This is an exploratory study without multiple comparison correction, and thus caution should be taken in interpreting these results, although such a combination of imaging and psychosocial assessments would be useful to
Role of funding source
This work was supported by Grant-in-Aid for Scientific Research B (23390290), S (22220003), a Grant-in-Aid for Young Scientist A (23680045), B (23791329) and on Innovative Areas (23118004, 23120009) from the Ministry of Education, Culture, Sports, Science and Technology of Japan, Takeda Science Foundation, The Uehara Memorial Foundation and Senshin Medical Research Foundation. Schizophrenia Research Group, Research Group for Schizophrenia sponsored by Astellas Pharma Inc.
Contributors
JM, MY and TM designed the study and wrote the protocol under the supervision of HF. SU and TU managed the literature searches and analyses. SU, JM, MY, KH, HF, RK, SF, YT, MK and AS collected the data. NS supervised the MRI data acquisition and processing. SU undertook the statistical analysis under the supervision of HF, HT, and TM. SU wrote the first draft of the manuscript, and contributed substantially to all subsequent drafts of the manuscript. All authors contributed to and have approved
Conflict of interest
All authors declare that they have no conflict of interest.
Acknowledgment
We would like to thank Prof. Rumi Tanemura, and most of all, to the patients and volunteers for participating in the study.
References (38)
- et al.
Subjective and objective quality of life, levels of life skills, and their clinical determinants in outpatients with schizophrenia
Psychiatry Research
(2008) - et al.
Neurocognitive deficits and quality of life in outpatients with schizophrenia
Progress in Neuro-Psychopharmacology and Biological Psychiatry
(2002) - et al.
Voxel-based morphometry—the methods
Neuroimage
(2000) - et al.
Unified segmentation
Neuroimage
(2005) - et al.
Neuroanatomical abnormalities in schizophrenia: a multimodal voxelwise meta-analysis and meta-regression analysis
Schizophrenia Research
(2011) - et al.
Meta-analysis of gray matter anomalies in schizophrenia: application of anatomic likelihood estimation and network analysis
Biological Psychiatry
(2008) - et al.
Patient outcomes in schizophrenia I: correlates with sociodemographic variables, psychopathology, and side effects
European Psychiatry
(2005) - et al.
Schizophrenia Quality of Life Scale: validation of the Japanese version
Psychiatry Research
(2002) - et al.
Structural correlates of psychopathological symptom dimensions in schizophrenia: a voxel-based morphometric study
Neuroimage
(2008) - et al.
Subjective and objective quality of life in schizophrenia
Schizophrenia Research
(2008)
Effects of discontinuation of long-term biperiden use on cognitive function and quality of life in schizophrenia
Progress in Neuro-Psychopharmacology and Biological Psychiatry
Subjective quality of life in first episode schizophrenia spectrum disorders with comorbid depression
Psychiatry Research
The personal impact of schizophrenia in Europe
Schizophrenia Research
Social cognition and frontal lobe pathology in schizophrenia: a voxel-based morphometric study
Neuroimage
The moderator-mediator variable distinction in social psychological research: conceptual, strategic, and statistical considerations
Journal of Personality and Social Psychology
Subjective assessments of the quality of life, well-being and self-efficacy in patients with schizophrenia
Psychiatry and Clinical Neurosciences
Psychiatric symptoms and quality of life in schizophrenia: a meta-analysis
Schizophrenia Bulletin
The anatomy of first-episode and chronic schizophrenia: an anatomical likelihood estimation meta-analysis
The American Journal of Psychiatry
Subject and observer-rated quality of life in schizophrenia
Acta Psychiatrica Scandinavica
Cited by (12)
Functional brain substrate of quality of life in patients with schizophrenia: A brain SPECT multidimensional analysis
2016, Psychiatry Research - NeuroimagingCitation Excerpt :Another recent study has shown an association between QoL and the neural activity in the prefrontal cortex during a verbal fluency task (Pu et al., 2013). Finally, a morphometric study using magnetic resonance imaging (MRI) has found correlations between cortical grey matter reductions and QoL (Ubukata et al., 2013). However, despite the multidimensional aspect of QoL (Lehman, 1983), these studies have investigated a global index or some QoL dimensions.
Converging models of schizophrenia - Network alterations of prefrontal cortex underlying cognitive impairments
2015, Progress in NeurobiologyCitation Excerpt :Imaging data during this phase showed global changes in neural connectivity (Friedman et al., 2008). Furthermore, both white and gray matters, especially cortical thickness have been shown altered in these patients, whose degree of changes may be correlated with their functional status (Kubota et al., 2013; Sasamoto et al., 2014; Ubukata et al., 2013). These patients may show a lack of motivation as well as difficulty in activating task-relevant networks.