Subtypes of schizophrenia: a cluster analytic approach.

OBJECTIVES: To identify empirical subtypes of schizophrenia, based upon the symptoms recorded over the duration of the illness, and to validate the resulting clusters against other systems that are used for subtyping schizophrenia. METHOD: Data for 55 symptoms of schizophrenia over the history of the illness from 107 chronic schizophrenia patients were analyzed using hierarchical cluster analysis with Euclidean distance and Ward's method. Except for 1 patient, all met DSM-III criteria. There were 40 men and 67 women, average (SD) age of 38.2 (9.91) years, with a mean (SD) hospitalization of 27.9 (27.35) months. RESULTS: No clear and unambiguous solution for the number of clusters was evident. Examination of the clusters led to further analysis of 2- and 6-cluster solutions. These were contrasted with DSM-III, DSM-III-R, and DSM-IV criteria and with the subtypes taken from the literature. There was limited support for any of these types, with none replicating, including the paranoid-nonparanoid distinction. CONCLUSIONS: Empirical clusters derived from lifetime symptom data failed to agree with either the established DSM or other empirically derived subtypes. Subtypes may have little utility when the variability of symptoms over the longitudinal course of the illness is considered.     

The role of estrogens in schizophrenia gender differences

The male/female differences that have been described in schizophrenia are important because they may ultimately shed light on factors that mediate the expression of schizophrenic illness. The hypothesis of this article is that estrogens, either directly or indirectly, modify symptom expression and account for many of the observed gender differences. The role of sex hormones is divided into organizational and activational effects. Organizational effects take place during a critical period in fetal life and put a permanent stamp on the developing brain. Activational effects are the direct influences of circulating hormones that appear when hormonal levels rise, and wane when hormonal levels drop. Because levels of sex hormones in adult women fluctuate during the menstrual cycle, cyclic effects of high and low female hormones may induce specific responses by the adult female brain. All these effects have implications for genetic, environmental, pharmacological, neurocognitive, clinical, and epidemiological research in schizophrenia.     

Attitudes toward medication in inpatients with schizophrenia: a cluster analytic approach

Attitudes toward medication (ATM) exert an influential role on compliance. Ninety-nine inpatients with schizophrenia were administered the Rating of Medication Influences scale (ROMI). Patients were also rated using: i) the Health of the Nation Outcome Scales, ii) the Global Assessment of Functioning scale, iii) the Clinical Global Impression, Severity scale, and iv) the WHO Quality Of Life assessment, Brief Version. Seventy-seven subjects (77.8%) completed the ROMI interview. Cluster analysis identified the following four clusters: i) Ambivalence (n=17; 22%); ii) Problems with Patient, Family, Alliance (n=11; 14.3%); iii) Medication Affinity, Positive Influence from Others (n=30; 39%); and iv) Illness, Medication, Label Distress (n=19; 24.7%). Clusters did not differ in demographic or clinical variables except for depressed mood and physical well-being, which were, respectively, lower and higher in patients with mostly negative ATM. Based on rater assessment, psychotic symptoms were related to negative ATM independently of their severity, and the family played a central role in the expression of negative attitudes. ATM were relatively independent of clinical and psychosocial variables. The existence, in each cluster, of both external and inner motivations underpinning ATM suggests that therapeutic interventions must take into account both patients and their broader living contexts.     

The role of gender in studies of ventricle enlargement in schizophrenia: a predominantly male effect

Two previously reported neuroimaging studies from the authors' laboratory demonstrated larger lateral ventricles in schizophrenic patients than in normal control subjects. This diagnostic effect was accounted for almost entirely by the male subjects. In this report the role of gender is further explored through reexamining these data sets and those of two earlier studies. Although Gender by Diagnosis effects were not demonstrated, in three of the four studies male schizophrenic subjects had significantly larger ventricles than their control counterparts; there were no differences among the female subjects. One study suggested the opposite effect, but this may be attributable to a non-representative control group.     

亚型分类在理解精神分裂症疾病进程中的作用：“缺陷综合征”举例

徐教授[1]对精神分裂症亚型的应用进行了贴切而有说服力的描述,提出了今后需要继续以其他方式对其进行分型的观点。他指出,作为可观察到的临床＂表型＂,精神分裂症的分型很早就得以使用,并且一直被用于指导精神分裂症的诊断和治疗。尽管历史悠久,但是来自上海和西方国家的研究表明[2,3],由美国和欧洲国家所定义的精神分裂症亚型中,除了偏执型和未定型精神分裂症以外,其他亚型很少使用,仅有不足5%的精神分裂症患者被诊断为这些亚型。而且,广泛使用的亚型诊断并不稳定：在整个疾病过程中,     

也谈精神分裂症的分型问题

今年（2011年）恰是精神分裂症命名（E.Bleuler,1911年）100周年,又值ICD及DSM要出新版之际,而且DSM-5将取消精神分裂症的分型（http：//www.dsm5.org）,因此讨论一下精神分裂症的分型问题不无意义。精神分裂症是20世纪以来最常见的重性精神病之一,     

Psychiatric comorbidity among adults with schizophrenia: A latent class analysis

Schizophrenia is a severe mental illness that often co-occurs with and can be exacerbated by other psychiatric conditions. There have not been adequate efforts to examine schizophrenia and psychiatric comorbidity beyond pairwise examination using clusters of diagnoses. This study used latent class analysis to characterize patterns of 5-year psychiatric comorbidity among a national sample of adults with schizophrenia. Baseline data from 1446 adults with schizophrenia across 57 sites in the United States were analyzed. Three latent classes were identified labeled Solely Schizophrenia, Comorbid Anxiety and Depressive Disorders with Schizophrenia, and Comorbid Addiction and Schizophrenia. Adults in the Solely Schizophrenia class had significantly better mental health than those in the two comorbid classes, but poorer illness and treatment insight than those with comorbid anxiety and depressive disorders. These results suggest that addiction and schizophrenia may represent a separate latent profile from depression, anxiety, and schizophrenia. More research is needed on how treatment can take advantage of the greater insight possessed by those with schizophrenia and comorbid anxiety and depression.     

Clinical subtypes of schizophrenic disorders: a cluster analytic study

Two hundred and fifty-five psychiatric inpatients with a definite diagnosis of DSM-IV schizophrenic disorder were examined by means of the Structured Clinical Interview and rated on the 30 main items of the Positive and Negative Syndrome Scale (PANSS). Patients' scores were subjected to a cluster analysis, using Ward's method. Cluster analysis indicated the existence of five groups. The first group (n = 46) comprised patients with overall psychopathology of minimal severity, the second group (n = 39) patients with severe positive symptoms along with symptoms of psychomotor excitement, the third group (n = 58) patients with severe positive psychopathology only, the fourth group (n = 34) patients with severe positive negative depressive and cognitive symptoms and, finally, the fifth group (n = 78) patients with severe negative symptoms only. Patients in the first and third groups were older and their illnesses were of longer duration compared to those of the remaining groups. With respect to DSM-IV clinical types of schizophrenic disorders, the paranoid type predominated in the second and the third groups, whereas the disorganized and catatonic types were markedly overpresented in the fifth group.     

The role of sex on stability and change of depression symptom subtypes over 20 years: a latent transition analysis

Prospective studies investigating the long-term stability of depression symptom subtypes are rare. Moreover, sex has received little attention as a predictor. This study aimed to investigate the role of sex on stability and transition patterns of depressive symptom subtypes over 20 years. The data were drawn from three follow-ups (1988, 1999, and 2008) of the longitudinal Zurich Study. Latent transition analyses were fitted to the data of 322 subjects, using depressive symptoms from the face-to-face interviews. The stable classes were characterized by psychosocial correlates. Three subtypes were identified: ‘severe atypical,’ ‘severe typical,’ and ‘moderate.’ While stability of the severe atypical and moderate subtype was relatively high and increased over time (70–71; 45–90 %), stability of the severe typical subtype was lower (45–48 %). Females had a higher risk of being in the severe atypical subtype and exhibited more transitions, particularly with respect to the severe typical subtype. In contrast, males displayed more stable subtypes. The stable severe atypical subtype was associated with comorbid eating disorders as well as psychosis syndromes, whereas the stable severe typical subtype was associated only with psychosis syndromes. Our results provide first evidence for the notion that long-term stability and transition patterns differ by sex and depression subtypes. This finding has received too little attention in previous research and should be considered in treatments.     

Formal thought disorder in schizophrenia: a factor analytic study.

The Thought, Language and Communication Scale (TLC) was studied in a sample composed of 115 DSM-III-R schizophrenic patients admitted to an acute inpatient unit. A principal component analysis with varimax rotation was performed to explore the possibility of the existence of syndromes within the formal thought disturbances. Seven factors were found to have eigen values greater than 1 and five showed appropriate internal consistency. The first factor, or disorganization factor, was close to the Scale for the Assessment of Positive Symptoms (SAPS) formal thought disturbance subscale. The second, or negative factor (perseveration, poverty of speech and content), was moderately correlated with poor premorbid functioning and poor response to neuroleptic treatment. The third and fourth factors were, respectively, formed by stilted speech plus word approximations, and neologisms plus clanging. The fifth factor (distractibility and blocking), as well as the first two factors, were correlated to the Scale for the Assessment of Negative Symptoms (SANS) attention subscale.     

Variability of ecological executive function in children and adolescents genetically at high risk for schizophrenia: a latent class analysis

Executive impairments have been observed both in patients with schizophrenia and in their unaffected first-degree relatives. Very few studies have investigated neurocognitive subgroups in unaffected first-degree relatives and in healthy participants using data-driven methods. The study included a high-risk group consisting of 100 unaffected young offspring and siblings of patients with schizophrenia and 198 healthy controls, all aged between 9 and 23 years. Executive function, victimization, and emotional and behavioral problems of participants were assessed by a series of self-report scales. Neurocognitive subgroups were investigated using latent class analysis of executive function measures. Four neurocognitive clusters were identified: a good performance cluster, a good self-control cluster, a low self-control cluster, and a severe impairment cluster. Participants in severe impaired executive function cluster reported a significantly higher level of victimization and had more prominent emotional and behavioral problems than the good performance cluster. Neurocognitive differences between high-risk young people and healthy controls were driven by individuals who have severe and global, rather than selective, executive deficits. Our results may provide clues to an explanation of the mechanisms behind executive impairments in young individuals at genetic risk and help to identify new targets for early interventions.

     

The mystery of schizophrenia. The role of a preventive approach in the treatment of mental illness

Despite decades of research, there is still a disquieting amount of unanswered questions concerning the genesis as well as the efficient therapy of schizophrenia. The classic approaches emphasizing genetic and family influences were followed by more comprehensive ones that focus on the interplay between the cognitive and the emotional social symptoms of the illness. The demand-access-matching model and, perhaps even more clearly, the cognitive appraisal model seek to integrate biological and early childhood experience factors and show their impact on cognitive as well as emotional functioning. The health-psychosis-continuum model, on the other hand, offers a possible answer to the quantity-quality dilemma of psychotic symptoms. Following a review of the different approaches as well as recent findings in research, the present study outlines a possible route to the development of mental illness starting from a genetically determined more general vulnerability leading to non-specific cognitive dysfunct on in early childhood on to an impaired synchronicity finally leading to a distancing from external reality in the form of overt psychotic symptoms. The second part of the study focuses on the advantages and difficulties of the different therapeutic approaches to mental illness. Based on these approaches, the study outlines an alternative preventive model that, rather than focusing on the former dichotomies lays the emphasis on the early identification and detection of non-specific childhood cognitive dysfunction and early intervention to correct these. These interventions certainly require the close cooperation between psychologists, psychiatrists and special education experts.     

Phenomenology of hallucinations: a factor analytic approach

The present study was carried out with the aim of obtaining a factor analytic solution of parameters of hallucinations in schizophrenia. Seventy-five chronic hallucinating schizophrenic patients were assessed on the Phenomenology of Hallucinations Scale and Brief Psychiatric Rating Scale. A factor analytic solution was obtained by principal component analysis using varimax rotation. Two factors, 'reality of hallucinatory perception' and 'immersion in hallucination', were obtained. Findings are discussed in relation to existing literature.     

Phenomenological subtypes of severe bipolar mixed states: a factor analytic study

Objective

The correct identification of bipolar mixed states (MS) has important implications for clinical practice. The aim of the study was to define the multidimensional psychopathological structure of severe MS. To our knowledge, no factor analytical studies including only patients with MS, have been conducted before.

Methods

In the first week of hospitalization, we evaluated by HAM-D-17, YMRS, BPRS and CGI, 202 Bipolar I inpatients with MS according to DSM-IV criteria referred for an ECT trial. A Principal-component analysis followed by Varimax rotation was performed on the 24-item BPRS. The relationships among different symptomatological subtypes and other clinical characteristics were explored.

Results

Six interpretable factors were extracted: Psychotic-positive symptoms, Mania, Disorientation-Unusual Motor Behaviour, Depression, Negative Symptoms and Anxiety. On the basis of the highest z-scores, we found 6 “dominant” BPRS factor groups, that were statistically distinct and without significant overlap in the main symptomatological presentation. Only 29 (14.4%) of our patients could be described as “Dominant Manic” and 48 (23.8%) as “Dominant Depressive”; most importantly 125 (61.9%) were neither predominately-manic nor predominately-depressive. Variables including age, number of previous episodes, suicidal behavior and HAM-D and YMRS scores significantly differentiated the subtypes.

Conclusion

At least in the most severe forms, MS appears to represent more than the superposition of affective symptoms of opposite polarity. Anxiety, perplexity, psychotic experiences, motor disturbances and grossly disorganized behavior seem to arise from protracted intra-episodic instability and presence of a drive state influencing the mood state and the emotional resonance.     

精神分裂症家族史性别差异调查

目的 了解不同性别精神分裂症遗传的差异及父系、母系阳性家族史的差异.方法 对长沙市城、乡在我院住院的及同时段各社区进行免费药物求助的共1938例精神分裂症患者进行精神障碍遗传的问卷调查,发现精神分裂症阳性家族史患者253例,其中男性139例,女性114例.对家族史阳性率,先证者父系、母系、同胞子女患病情况作统计分析.结果 男性阳性家族史比率较女性稍低,但无统计学意义;父系、母系、同胞子女的阳性家族史无明显性别差异;母系阳性家族史明显高于父系.结论 遗传因素对精神分裂症有很大的影响,不同性别精神分裂症的阳性家族史无明显差异.精神分裂症中母系后代比父系后代有更高的发病风险.     

The sensitivity of somatic symptoms in post-stroke depression: a discriminant analytic approach

BACKGROUND: Somatic and neurocognitive symptoms of depression may overlap with the physical symptoms of stroke, and thus make the diagnosis of post-stroke depression difficult. AIM: To assess the sensitivity of individual depressive symptoms and their contribution to the diagnosis of post-stroke depression. PATIENTS AND METHODS: Two hundred and six patients with first-ever stroke, participating in a longitudinal study, were administered the Structured Clinical Interview for DSM-IV and the Hamilton Depression Rating Scale (HAM-D). In a discriminant analysis the relative contribution of the individual HAM-D items to the diagnosis of major depressive disorder was evaluated. RESULTS: The cumulative incidence of post-stroke major depressive disorder was 32%. The discriminant model based on HAM-D item scores was highly significant (p<0.001) and classified 88.3% of patients correctly as depressed or nondepressed. As expected, 'depressed mood' discriminated best between depressed and non-depressed stroke patients. 'Reduced interests' had a relatively low sensitivity and may in part reflect 'apathy', which often is considered a separate construct. With the exception of 'suicidal thoughts', most psychological symptoms, such as 'hypochondriasis', 'lack of insight' and 'feelings of guilt', were not very sensitive. Some somatic symptoms, such as 'reduced appetite', 'psychomotor retardation', and 'fatigue' had high discriminative properties. CONCLUSION: Psychological, neurocognitive and somatic symptoms of depression differ among themselves in terms of diagnostic sensitivity, and should be considered individually. Some somatic symptoms are highly sensitive for depression and should not be neglected by following an 'exclusive' or 'attributional' approach to the diagnosis of PSD.