The Relationship between Delirium and Statin Use According to Disease Severity in Patients in the Intensive Care Unit

Objective@#The aim of this study was to investigate the association between the use of statins and the occurrence of delirium in a large cohort of patients in the intensive care unit (ICU), considering disease severity and statin properties. @*Methods@#We obtained clinical and demographical information from 3,604 patients admitted to the ICU from January 2013 to April 2020. This included information on daily statin use and delirium state, as assessed by the Confusion Assessment Method for ICU. We used inverse probability of treatment weighting and categorized the patients into four groups based on the Acute Physiology and Chronic Health Evaluation II score (group 1: 0−10 - mild; group 2: 11−20 -mild to moderate; group 3: 21−30 - moderate to severe; group 4: ＞ 30 - severe). We analyzed the association between the use of statin and the occurrence of delirium in each group, while taking into account the properties of statins. @*Results@#Comparisons between statin and non-statin patient groups revealed that only in group 2, patients who were administered statin showed significantly higher occurrence of delirium (p = 0.004, odds ratio [OR] = 1.58) compared to the patients who did not receive statin. Regardless of whether statins were lipophilic (p = 0.036, OR = 1.47) or hydrophilic (p = 0.032, OR = 1.84), the occurrence of delirium was higher only in patients from group 2. @*Conclusion@#The use of statins may be associated with the increases in the risk of delirium occurrence in patients with mild to moderate disease severity, irrespective of statin properties.

Effect of Delayed Clozapine Initiation on Acute Treatment Response in Treatment-Resistant Schizophrenia / 대한정신분열병학회지

Objectives@#Recent studies have reported that delayed initiation of clozapine can affect clinical response in patients with treatment-resistant schizophrenia (TRS). This study aimed to explore the relationship between delayed initiation of clozapine and acute treatment response. @*Methods@#Sixty-five inpatients with TRS who started clozapine for the first time were included through a retrospective chart review. Acute treatment response was defined as a 30% reduction in the Positive and Negative Syndrome Scale score or a Clinical Global Impression of Improvement score of 1 (very much improved) or 2 (much improved) at 4 weeks after initiating clozapine. @*Results@#After meeting the TRS criteria, the mean delay for initiating clozapine was approximately 13.8 months. The delay was shorter in patients who showed a better response to clozapine in logistic regression analysis (p=0.037). @*Conclusion@#Our findings suggest that reducing the delay in initiating clozapine increases the effectiveness of clozapine in patients with TRS.

Clinical Correlates of QTc Prolongation in Patients with Schizophrenia :A Retrospective Study / 정신신체의학

Objectives@#：QTc prolongation due to antipsychotics is of major concern because it may lead to fatal ventricular arrhythmia such as torsade de pointes. However, few studies have been conducted on QTc prolongation due to antipsychotics, especially in South Korea. This study aimed to investigate how demographic and clinical variables affect QTc interval in patients with schizophrenia. @*Methods@#：By retrospectively reviewing medical records, we assessed QTc interval, demographic data and clinical features of 441 (175 males) patients with schizophrenia who admitted to the psychiatric ward of a general hospital. To explore the predictive factors for QTc interval, hierarchical regression analysis was performed with QTc interval as the dependent variable. @*Results@#：The mean QTc interval was 417.2±28.4 ms. In the hierarchical regression analysis, the use of shortacting antipsychotic injection was the strongest predictor of the QTc prolongation. @*Conclusions@#：This study demonstrated that the use of short-acting antipsychotic injection may affect QTc prolongation in patients with schizophrenia. This result suggests that more attention should be paid to the use of short-acting antipsychotic injection in the treatment of schizophrenia.

Neutrophil-Lymphocyte Ratio as Inflammatory Marker for Delirium:An Exploratory Study / 정신신체의학

Objectives@#：Delirium is a temporary brain dysfunction and systemic inflammation is important factor in its pathophysiology. Whether the neutrophil-lymphocyte ratio (NLR), one of the inflammatory markers, can be used as an inflammatory marker in delirium patients was investigated in comparison with C-reactive protein (CRP). @*Methods@#：We retrospectively reviewed the medical records of patients who were referred for consultation for delirium at hospital for one year. The NLR and CRP values at admission and delirium status were divided into the medical and the surgical treatment group, and the interaction between them was analyzed through repeated mea-sures ANOVA. @*Results@#：NLR was maintained without significant difference before and after delirium in the medical treat-ment group and the surgical treatment group, but CRP decreased in the medical treatment group and increased in the surgical treatment group during delirium, showing a significant interaction. @*Conclusions@#：In delirium patients, the NLR remained constant, but the CRP differed according to the treatment group and the delirium state. This suggests the possibility that NLR could be used complementary to CRP as an in-flammatory marker in delirium patients.

Clinical Characteristics, Drug Adherence to Antipsychotics and Medical Use Trends in Patients First Diagnosed with Psychotic Disorder: A Preliminary Study / 대한정신분열병학회지

OBJECTIVES: In this preliminary study, we investigated the clinical characteristics of patients who were first diagnosed with psychotic disorder and explored the impact of the adherence to antipsychotics on long-term medical use. METHODS: All national health insurance claims related to psychotic disorders including gender, age, income, and drug compliance, from January 1, 2008 to December 31, 2015, were examined. With trend test using Medication Possession Ratio (MPR), we compared the medical use between the compliant group (MRP≥0.8) and the comparative non-compliant group (0.2≤MPR<0.8). RESULTS: Among 28,095 participants in total, 16,239 patients (57.8%) were diagnosed as schizophrenia; the 30s were the most common (n=7,151, 25.5%). Drug compliance was generally low regardless of the diagnosis and was the lowest among 20s with the 40–60% range of income. The compliant group showed lower psychiatric and medical use than the comparative group in the following years (p<0.0001). CONCLUSION: These findings suggest that patients in the 20s and 30s with the 40–60% range of income, who are diagnosed with schizophrenia at the first psychiatric visit, may need more clinical and political attention. The results also emphasize the importance of initial drug adherence to antipsychotics in reducing long-term psychiatric costs.

Incidence and Procedure-Related Risk Factors of Delirium in Patients Admitted to an Intensive Care Unit / 정신신체의학

OBJECTIVES: Although delirium is a common complication among patients hospitalized in intensive care units(ICUs), little is known about the roles that diagnostic and therapeutic procedures play in its development. This study investigates the procedure-related risk factors of delirium in ICU patients. METHODS: All the consecutive patients admitted to the ICU between June 2016 and May 2017 were routinely evaluated for delirium by psychiatrists. In total, 1156 patients met the inclusion criteria and were retrospectively analyzed. A multiple logistic regression analysis was conducted to investigate independent risk factors of delirium development while adjusting for other characteristics. RESULTS: The age, Acute Physiology and Chronic Health Evaluation (APACHE II) score, proportion of patients who had undergone an operation, and proportion of patients who were foley catheterized, mechanically ventilated, and physically restrained were higher in the delirium group. The multiple logistic regression analysis confirmed that the use of restraint was an independent risk factor of delirium (odds ratio : 10.006 ; 95% confidence interval : 6.120–16.360 ; p<0.001). The patient factors independently associated with delirium were an advanced age and a higher APACHE II score. The incidence of delirium was 15.3%. CONCLUSIONS: There is a high prevalence of delirium influenced by potentially harmful procedures in patients in ICU settings. The use of physical restraint had the strongest association with the development of delirium. These findings advocate the need to target procedure-related risk factors such as the use of restraints as preventive intervention measures for ICU delirium.

The Effect of Psychological Factors on Postoperative Pain in Gastric Tumor Patients after Endoscopic Submucosal Dissection / 정신신체의학

OBJECTIVES: Since pain in cancer patients is an important factor that greatly affects the quality of life and prognosis, many attempts have been actively made to reduce the pain. Despite continuous effort on reducing pain after Endoscopic submucosal dissection (ESD), research has not been done on psychological factors as much as on biological factors affecting pain. The objective of this study is to investigate the psychological factors affecting postoperative pain in gastric tumor patients who underwent gastric ESD. METHODS: 91 gastric tumor patients who visited National Health Service Ilsan Hospital in Korean between May 2015 and June 2016, and received ESD were evaluated. Baseline characteristics including sociodemographic factors, anxiety, depression, and resilience were evaluated before the procedure. Multivariate logistic regression was done to analyze factors affecting postoperative pain. RESULTS: The group with high postoperative pain showed lower alcohol consumption and higher depressive symptom scores than the group with low postoperative pain. Also, the group with high postoperative pain showed lower total resilience score with lower subtotal scores in self-control and positive item. Multivariate logistic regression analysis of the postoperative pain showed that patients with lower score in self-control of resilience [odd ratio (OR), 0.911 ; 95% CI, 0.854–0.971, p=0.004) reported more pain after ESD. CONCLUSIONS: This study showed that patients with lower self-control ability of resilience felt more pain after ESD. Among the psychological factors evaluated in this study, resilience of an individual seems to have effect on pain.

Changes in heart rate variability of patients with delirium in intensive care unit.

Delirium is an important syndrome in intensive care unit (ICU) patients, however, its characteristics are still unclear. Many evidences showed that this syndrome can be related to the autonomic instability. In this study, we aimed to investigate the possible alterations of autonomic nervous system (ANS) in delirium patients in ICU. Electrocardiography (ECG) of every ICU patient was measured during routine daily ICU care, and the data were gathered to evaluate the heart rate variability (HRV). HRV of total 60 patients were analyzed in time, frequency and non-linear domains. As a result, we found that heart rates of delirium patients were more variable and irregular than non-delirium patients. These findings may facilitate early detection and prevention of delirium in ICU.

A Preliminary Study on the Circadian Rhythm of Autonomic Nervous System in Patients Admitted to Intensive Care Unit, Using the Heart Rate Variability

OBJECTIVES: normal circadian rhythm of autonomic nervous system function stands for the daily change of sympathetic and parasympathetic modulation, which can be measured by heart rate variability (HRV). Generally, patients in the intensive care unit (ICU) are prone to sleep-wake cycle dysregulation, therefore, it may have an influence on the circadian rhythm of autonomic nervous system. This study was designed to interpret possible dysregulation of autonomic nervous system in ICU patients by using HRV. METHODS: HRV was assessed every 3 hours in 21 ICU patients during a 7-minute period. The statistical differences of HRV features between the morning (AM 6 : 00–PM 12 : 00), and the afternoon (PM 12 : 00–PM 18 : 00) periods were evaluated in time domain and frequency domain. RESULTS: Patients showed significantly increased normalized power of low frequencey (nLF), absolute power of low frequencey (LF)/absolute power of high frequencey (HF) in the afternoon period as compared to the morning period. However, normalized power of high frequency (nHF) was significantly decreased in the afternoon period. There was no statistically significant difference between the morning period and the afternoon period in the time domain analysis. CONCLUSIONS: The increased sympathetic tone in the afternoon period supports possible dysregulation in the circadian rhythm of autonomic nervous system in ICU patients. Future studies can help to interpret the association between autonomic dysregulation and negative outcomes of ICU patients.