The QLICD-SC (V2.0) used in the present study is a schizophrenia scale in the Quality of Life Instruments for Chronic Diseases, including a common module QLICD-GM (general module) and a schizophrenia specific module, which is more practical for studying the HRQOL of schizophrenics. We found that scores of schizophrenic patients ranked highest in social function, followed by physical function, psychological function and special module. Grattan et al. showed that patients had higher psychological stress sensitivity due to schizophrenia symptoms, especially after experiencing negative life events [26]. As a result, people with schizophrenia have lower psychological functioning scores compared to other chronic conditions. Physical function primarily reflects the patients’ basic physiological conditions, such as appetite, sleep and fatigue. Vancampfort (2016) demonstrated that patients’ physical fitness was markedly poorer than healthy controls as a result of typical symptoms such as delusions, hallucinations, or disruptions in daily functioning [27]. Schizophrenia frequently manifests in late adolescence or early adulthood [28]. Patients may fail to express their emotions due to alexithymia, which translate into troubles in social reintegration [29, 30] and affects their score of social function.
There are numerous factors affecting the HRQOL of schizophrenic patients, including socio-demographic factors, physiological factors, psychological factors and clinical principles. Therefore, the present study primarily used simple correlation analysis and multiple linear regression to explore whether clinical objective indicators and socio-demographic factors were related to the QLICD-SC (V2.0) domains and total scale scores. In terms of psychological function, the result of multiple linear regression indicated that sex influences HRQOL. There are gender disparities in the condition of people with schizophrenia, according to several research[17, 31, 32], which may be related to the avenues to deal with stress.
Regarding physical function, phosphorus is one of the factors, which also affects the total score. Numerous studies stressed that phosphorus levels correlate with the severity of psychiatric disorders [33, 34, 35]. For instance, schizophrenia patients have reduced amounts of phosphorus, according to Jamilian(2012) and Baj (2020) [33, 34]. In Chen's (2017) experiment, phosphorus levels rose after 3.8 weeks of antipsychotic medication therapy, indicating higher HRQOL [35]. But this study's findings revealed a negative association between phosphorus and HRQOL ratings may be because the blood samples were taken on the second day of admission and the patients' symptoms improved after medication but phosphorus levels did not change significantly in the short term. However, high level phosphorus in the body leads to phosphorus and calcium antagonism, the blood calcium in the blood reduces, resulting in osteoporosis, which also affects HRQOL. Stubbs B’ s(2014) study proved that the bone loss of schizophrenics occurred earlier, causing the prevalence of osteoporosis to be higher than in healthy people [36]. Therefore, monitoring phosphorus content in blood helps clinicians have a deeper understanding of patients’ HRQOL, although the mechanism is still unclear and not entirely consistent [37].
When it comes to special module, eosinophils is one of the factors, which will increase after taking antipsychotics [38]. That may be the reason why the patients’ condition alleviate and scores in special module and total scale increase. However, the abnormal increase of eosinophils can lead to serious problems. For example, olanzapine has been found to cause drug reactions with eosinophilia and systemic symptoms (DRESS) [39]. The DRESS syndrome can also be attributed to aripiprazole and quetiapine, as the drugs possibly lead to abnormal amounts of eosinophils [40, 41]. Therefore, paying more attention to these indicators can reflect patients’ condition, which is beneficial to doctors take action to treat patients even before significant symptoms appear.
This paper has the limitation that it is cross-sectional in design. Therefore, the effect of the treatment intervention cannot be analyzed. Thus, longitudinal investigations are expected to do. In addition, the subjects were all hospital patients, which had regional limitations. Future studies should widen the scope of investigation to include other variables. The coefficient of determination R2 for each model was not high enough, suggesting that our selection clinical indicators for measurement have certain limitations. Further analysis should be made on the factors affecting the HRQOL of schizophrenic patients.