Schizoid-like features and season of birth in a nonpatient sample

doi:10.1016/j.schres.2007.12.479

Schizophrenia Research

Volume 103, Issues 1–3, August 2008, Pages 151-155

https://doi.org/10.1016/j.schres.2007.12.479 Get rights and content

Abstract

Objectives

People with the deficit subtype of schizophrenia differs from others with schizophrenia with regard to risk factors, signs and symptoms, biological correlates, treatment response, and course of illness. The deficit group, which is characterized by decreased social interests and a lack of depression, has a well-replicated association with June/July birth, which contrasts with the association of schizophrenia as a whole with winter birth. As some of the correlates of schizophrenia are found in subclinical form in the schizophrenia spectrum, we hypothesized that June/July birth would be associated with the combination of decreased sociality in the absence of depression in a nonpatient group as well.

Methods

The Beck Depression Inventory and Chapman's Perceptual Aberration, Magical Ideation, and Social Anhedonia scales were administered to university students. The Perceptual Aberration and Magical Ideation scale scores were combined into a single psychotic-like symptom score (PerMag). Blind to month of birth, each subject (N = 425) was given a score that quantified the combination of social anhedonia and an absence of depression. Analyses were then performed in subjects in the upper 50% of PerMag scores who had complete data (N = 171, 27.5% male).

Results

June/July birth (p = .037) and male gender (p = .002) were both found to be associated with higher scores on the combination of social anhedonia and a low depression score; the interaction of these factors was not significant.

Conclusions

These results suggest that the same seasonal factor that contributes to the risk of deficit schizophrenia may affect brain development and personality characteristics in the general population.

Introduction

Beyond the well-replicated finding of a seasonality of birth in persons with schizophrenia (Torrey et al., 1997), there has been a growing body of evidence pointing to season of birth effects in areas such as personality traits (Chotai et al., 2001, Tochigi et al., 2004), academic achievement (Fieder et al., 2006), mortality (Doblhammer and Vaupel, 2001), and medical disorders, including celiac disease (Ivarsson et al., 2003), language impairment (Hauschild et al., 2005) and possibly diabetes (McKinney, 2001). Seasonality of births is likely to result from a fluctuating seasonal exposure in a population. These exposures would in turn affect the developing embryo or fetus, leading to a higher risk of disease in the future. Seasonal exposures, such as influenza (Dushoff et al., 2004), vulnerability to vitamin D deficiency (Mackay-Sim et al., 2004), and seasonally bound ovopathy (Pallast et al., 1994) have been proposed as possibly responsible for the seasonality of birth in schizophrenia.

In contrast to the well-reported winter birth excess in schizophrenia broadly defined (Torrey et al., 1997), deficit schizophrenia, which is characterized by primary, and enduring negative symptoms, has a relatively strong association with June/July birth (Kirkpatrick et al., 2002a, Kirkpatrick et al., 1998, Kirkpatrick et al., 2002b, Messias and Kirkpatrick, 2001, Messias et al., 2004, Tek et al., 2001b). The validity of the deficit subtype is supported by studies showing differences from other, nondeficit schizophrenia with regard to other risk factors, signs and symptoms, biological correlates, treatment response, and course of illness (Cohen et al., 2007, Dickerson et al., 2006, Kirkpatrick et al., 2001, Mucci et al., 2007). Patients with deficit schizophrenia have elevated scores on Social and Physical Anhedonia, as measured by the Chapman “psychosis proneness” scales, compared to other patients with schizophrenia (Kirkpatrick and Buchanan, 1990). Despite this greater anhedonia, they are also less depressed than other patients with schizophrenia, consistent with a true apathy (Kirkpatrick et al., 1996, Kirkpatrick et al., 1993, Kirkpatrick et al., 1994).

As some features of schizophrenia are found in subclinical form in nonpatient groups, and personality traits have been associated with a seasonality of births (Chotai et al., 2001, Tochigi et al., 2004), we hypothesized that June/July birth would be associated with the combination of decreased sociality in the absence of depression in a nonpatient group as well.

Section snippets

Methods

The sample consisted of university undergraduate students who volunteered to participate in a study of cognition and symptoms. Because cognitive tests were administered in addition to the Chapman Scales, only English speaking Americans were included in the study as the tasks employed were normed on that group. Thus, it is unlikely any subjects were reared outside of North America. The protocol was approved by the Institutional Review Board at the University of Maryland Baltimore.

Results

Females comprised the majority of the sample (72%; n = 306; total N = 426). The sample was 60% Caucasian, , 23% African-American, 14% Asian/Pacific Islander, 2% Hispanic, and < 1% other. The mean age was 20.1 ± 3.5, with no significant different between males and females. Among subjects in the upper 50% of PerMag scores, 171 had complete data (27.5% male). Males (n = 47) had a significantly higher PDS score (.5 ± 1.5 vs. − .2 ± 1.3). Subjects born in June/July (n = 25) had a significantly higher PDS score (.48 ±

Discussion

In a nonpatient sample, June/July birth was associated with anhedonia in the absence of depression, a pattern similar to that found in deficit schizophrenia (Kirkpatrick et al., 2002a, Kirkpatrick et al., 1998, Kirkpatrick et al., 2002b, Messias and Kirkpatrick, 2001, Messias et al., 2004, Tek et al., 2001b). This pattern was found in subjects who, as a group, also had very mild psychotic-like symptoms. We also found an association of these personality characteristics with male gender. The

Role of funding source

None.

Contributors

None.

Conflict of interest

None.

Acknowledgement

None.

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Early versus late risk factors for deficit and nondeficit schizophrenia
2022, Revista de Psiquiatria y Salud Mental
Citation Excerpt :
Winter birth has been associated with an excess of schizophrenia since 1929 and replicated many times,9 but when distinguishing between deficit and nondeficit types, both a review from 20017 and a pooled analysis from 6 countries in 200410 indicate that summer birth is associated with the deficit type of schizophrenia. Interestingly, a study by Kirkpatrick et al. suggested that summer birth is not only associated with the deficit subtype of schizophrenia but also with social anhedonia and low depression score in a nonpatient group.11 Recently, it has been shown that post-traumatic stress disorder (PTSD) is associated with secondary negative symptoms in schizophrenia whereas no such association was found among patients with primary negative symptoms (DS).12
We examined whether timing of known risk factors for schizophrenia may influence the development of schizophrenia with primary negative symptoms.
This cross-sectional single-centre study in England used a clinical cohort of 167 clozapine-treated schizophrenia patients. Deficit and nondeficit schizophrenia models were used as clinical proxies of patients with and without primary negative symptoms respectively. Patients were assessed using the Schedule for the Deficit Syndrome. We examined previously replicated risk factors (family history of psychosis, advanced paternal age, male gender, birth weight <3000 g, summer birth, cannabis use, exposure to physical or sexual abuse and/or bullying) as well as other traumatic events for deficit and nondeficit schizophrenia.
We found a distinct risk factor pattern for the two groups. Compared to the nondeficit group, patients with deficit schizophrenia reported a significantly lower prevalence of cannabis use (p = 0.005) at the time of first-episode psychosis (FEP), physical or sexual abuse (p = 0.033) prior to FEP, less exposure to crime-related traumatic events (p = 0.012) and significantly associated with summer birth (p = 0.017). The groups did not differ in terms of family history of psychosis, advanced paternal age, male gender, or low birth weight. To account for multiple comparisons, a confirmatory analysis was performed using logistic regression which yielded similar results except that summer birth no longer reached statistical significance.
Our results suggest the timing of the insult may influence the symptom presentation, with insults later in life (cannabis or traumatic events) being associated with psychotic presentation and less with primary negative symptoms.
Examinamos si la cadencia en la aparición de los factores de riesgo conocidos para la esquizofrenia podría influir en el desarrollo de la esquizofrenia con síntomas negativos primarios.
Este estudio transversal en un centro en Inglaterra utilizó una cohorte clínica de 167 pacientes con esquizofrenia tratados con clozapina. Los criterios de esquizofrenia deficitaria y no deficitaria se utilizaron como aproximación clínica para categorizar pacientes con y sin síntomas negativos primarios, respectivamente. Los pacientes fueron evaluados utilizando el Inventario para la Esquizofrenia Deficitaria. Examinamos únicamente factores de riesgo previamente replicados (antecedentes familiares de psicosis, edad paterna avanzada, sexo masculino, peso al nacer <3.000 g, nacimiento en verano, consumo de cannabis, exposición a abuso físico o sexual y/o acoso escolar), así como otros eventos traumáticos para la esquizofrenia deficitaria y la no deficitaria.
Encontramos un patrón de factores de riesgo distinto para los dos grupos. En comparación con el grupo sin déficit, los pacientes con esquizofrenia deficitaria presentaron una prevalencia significativamente menor de consumo de cannabis (p = 0,005) en el momento del primer episodio de psicosis (PEP), mayor frecuencia de abuso físico o sexual (p = 0,033) antes del PEP, menor exposición a eventos traumáticos relacionados con el crimen (p = 0,012) y significativamente asociados con el nacimiento en verano (p = 0,017). Los grupos no difirieron en términos de antecedentes familiares de psicosis, edad paterna avanzada, sexo masculino o bajo peso al nacer. Para tener en cuenta las comparaciones múltiples se realizó un análisis confirmatorio mediante regresión logística que arrojó resultados similares, excepto que el parto en verano ya no alcanzó significación estadística.
Nuestros resultados sugieren que el momento del ataque (factor de riesgo) puede influir en la presentación de los síntomas, ya que los ataques más tarde en la vida (cannabis o eventos traumáticos) se asocian con la presentación psicótica y menos con los síntomas negativos primarios.
Season of birth and subclinical psychosis: Systematic review and meta-analysis of new and existing data
2015, Psychiatry Research
Citation Excerpt :
It is worth noting that neither of these two studies seemed to bias subsequent results of the meta-analysis. First, using a very particular methodological design, Kirkpatrick et al. (2008) conclude that summer SOB is a risk factor for a (non-clinical) proxy for the schizophrenia deficit syndrome (Table 2). This conclusion is derived from a new psychometric measure in which scores from the Beck Depression Inventory are subtracted from those of the Social Anhedonia Scale (i.e., anhedonia in the absence of depression).
Season of birth (SOB) has been shown to modify the risk of several health outcomes, including a number of neuropsychiatric disorders. Empirical evidence indicates that subclinical forms of psychosis in the general population share some risk factors with categorical diagnoses of psychosis. Hence, by systematically reviewing and meta-analyzing new and existing data, the current work aimed to determine whether there is evidence of an association between winter SOB and subclinical psychosis in the general population. Our meta-analytic results do not indicate an association between winter SOB and schizotypy in adult populations, although they indicate winter SOB may be a risk factor for psychotic experiences or symptoms in children around 12–15 years (OR=1.12, 95%CI:1.03–1.21). In the whole new dataset for adults (n=481, mean age=22.8 years) no association was detected in either an unadjusted model or adjusting for gender and age. Overall, our results indicate that the association between winter SOB and increased subclinical psychosis may hold in children, but does not in the broad general adult population. Nevertheless, the epidemiological and clinicopathological significance of winter SOB as a risk factor for subclinical psychosis would probably be slight due to the small effect sizes indicated by the reports available to date.
Inflammatory markers in antipsychotic-naïve patients with nonaffective psychosis and deficit vs. nondeficit features
2012, Psychiatry Research
Newly diagnosed, antipsychotic-naïve patients with nonaffective psychosis appear to have increases in pro-inflammatory cytokines. Patients characterized by primary, enduring negative symptoms (deficit symptoms) differ from patients without such features with regard to course of illness, treatment response, risk factors and metabolic disturbances. We hypothesized that they would also differ on concentrations of the inflammatory markers interleukin-6 (IL6) and C-reactive protein (CRP). Newly diagnosed, antipsychotic-naïve patients with nonaffective psychosis were categorized into deficit (N = 20) and nondeficit (N = 42) groups, and were matched on age, gender, body mass index, smoking, cortisol level, socioeconomic status, and the severity of psychotic symptoms. Fasting concentrations of IL6 were significantly higher in deficit (mean [S.D.]) (8.0 pg/ml [12.7]) than nondeficit patients (0.3 pg/ml [1.3]). CRP levels were also significantly higher in the deficit patients (0.3 mg/dl [0.4]) vs. (0.2 mg/dl [0.4]), respectively. In contrast, 2-h glucose concentrations (2HG) in a glucose tolerance test were lower in the deficit than the nondeficit group. Our results show a double dissociation with regard to glucose intolerance and inflammation: the deficit group has greater inflammation, but less severe glucose intolerance. These results provide further evidence for the validity of the deficit/nondeficit categorization.
Taxometric analyses of paranoid and schizoid personality disorders
2012, Psychiatry Research
There remains debate about whether personality disorders (PDs) are better conceptualized as categorical, reflecting discontinuity from normal personality; or dimensional, existing on a continuum of severity with normal personality traits. Evidence suggests that most PDs are dimensional but there is a lack of consensus about the structure of Cluster A disorders. Taxometric methods are adaptable to investigating the taxonic status of psychiatric disorders. The current study investigated the latent structure of paranoid and schizoid PDs in an epidemiological sample (N = 43,093) drawn from the National Epidemiological Survey on Alcohol and Related Conditions (NESARC) using taxometric analyses. The current study used taxometric methods to analyze three indicators of paranoid PD — mistrust, resentment, and functional disturbance — and three indicators of schizoid PD — emotional detachment, social withdrawal, and functional disturbance — derived factor analytically. Overall, taxometrics supported a dimensional rather than taxonic structure for paranoid and schizoid PDs through examination of taxometric graphs and comparative curve fit indices. Dimensional models of paranoid and schizoid PDs better predicted social functioning, role-emotional, and mental health scales in the survey than categorical models. Evidence from the current study supports recent efforts to represent paranoid and schizoid PDs as well as other PDs along broad personality dimensions.
Relationships between season of birth, schizotypy, temperament, character and neurocognition in a non-clinical population
2012, Psychiatry Research
Citation Excerpt :
For men, however, the absence of a significant association between winter birth and SPQ score in the present study might be due to the type II error since the mean total SPQ score was higher in winter-born men than in the remaining men (i.e., 15.1 ± 11.4 vs. 13.1 ± 10.7). On the other hand, as mentioned earlier, findings from the three other precedent studies that have investigated the season of birth effect on schizotypy are not in line with the present one; two studies (Reid and Zborowski, 2006; Kirkpatrick et al., 2008) reported different relationships between season of birth and schizotypy from the present one, and one study (Cohen and Najolia, 2011) did not find any such significant association although this study observed that no less than 60% of individuals within the schizotypy group reporting a diagnosis of schizophrenia or prior hospitalization had been born during winter months. Given that the four studies (Reid and Zborowski, 2006; Kirkpatrick et al., 2008; Lahti et al., 2009) including the present one that found any significant relationship between season of birth and schizotypy were conducted in higher latitude regions of 35° to 60° whereas the study by Cohen and Najolia (2011) was conducted in a subtropical region with relatively mild winters, this discrepancy may have stemmed, at least partly, from the differences in latitude, as in the aforementioned schizophrenia literature.
While schizophrenia has been associated with a slight excess of winter/early spring birth, it is unclear whether there is such an association in relation to schizotypal personality traits. Season of birth has also been reported to relate to temperament and character personality dimensions and cognitive functioning. Moreover, non-clinical schizotypy has been shown to be associated with mild cognitive impairment, although its precise nature is yet to be elucidated. Here we examined the relationships between season of birth, schizotypal traits, temperament and character, and cognitive function. Four hundred and fifty-one healthy adults completed the Schizotypal Personality Questionnaire (SPQ). The Temperament and Character Inventory (TCI) and a neuropsychological test battery consisting of full versions of the Wechsler Memory Scale-Revised and the Wechsler Adult Intelligence Scale-Revised, and the Wisconsin Card Sorting Test, were also administered to most of the participants. The total SPQ score of those born in winter was significantly higher than that of the remaining participants. Season of birth was not significantly associated with any of the TCI dimensions or cognitive test results. Significant but mild relationships between higher SPQ scores and lower scores on some aspects of IQ were observed. These results support the notion that schizotypy and schizophrenia are neurodevelopmental conditions on the same continuum.
Influence of photoperiod on hormones, behavior, and immune function
2011, Frontiers in Neuroendocrinology
Citation Excerpt :
Late gestation and birth in short days, in both northern and southern hemispheres, is associated with increased prevalence of schizoaffective disorder, autism, and major depression in the adult population [135,298]. Season of birth may also differentially affect subtypes of affective disorders, as long-day births are associated with an increase in the deficit subtype of schizophrenia [160] and risk of completed suicide [89]. Some of these disorders can be modeled by early life differences in photoperiod.
Photoperiodism is the ability of plants and animals to measure environmental day length to ascertain time of year. Central to the evolution of photoperiodism in animals is the adaptive distribution of energetically challenging activities across the year to optimize reproductive fitness while balancing the energetic tradeoffs necessary for seasonally-appropriate survival strategies. The ability to accurately predict future events requires endogenous mechanisms to permit physiological anticipation of annual conditions. Day length provides a virtually noise free environmental signal to monitor and accurately predict time of the year. In mammals, melatonin provides the hormonal signal transducing day length. Duration of pineal melatonin is inversely related to day length and its secretion drives enduring changes in many physiological systems, including the HPA, HPG, and brain–gut axes, the autonomic nervous system, and the immune system. Thus, melatonin is the fulcrum mediating redistribution of energetic investment among physiological processes to maximize fitness and survival.

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Schizoid-like features and season of birth in a nonpatient sample

Abstract

Objectives

Methods

Results

Conclusions

Introduction

Section snippets

Methods

Results

Discussion

Role of funding source

Contributors

Conflict of interest

Acknowledgement

Clin. Psychol. Rev.

Psychiatry Res.

Psychiatry Res.

Psychiatry Res.

Schizophr. Res.

Int. Rev. Neurobiol.

Schizophr. Res.

Schizophr. Res.

Psychiatry Res.

Schizophr. Res.

Neurosci. Lett.

Schizophr. Res.

Biol. Psychiatry

Positive thought disorder in a hypothetically psychosis-prone population

J. Abnorm. Psychol.

Magical ideation as an indicator of schizotypy

J. Abnorm. Psychol.

Season of birth variations in the temperament and character inventory of personality in a general population

Neuropsychobiology

Neuropsychology of the deficit syndrome: new data and meta-analysis of findings to date

Schizophr. Bull.

Saccadic eye movements in families multiply affected with schizophrenia: the Maudsley Family Study

Am. J. Psychiatry

Deficit schizophrenia: association with serum antibodies to cytomegalovirus

Schizophr. Bull.

Lifespan depends on month of birth

Proc. Natl. Acad. Sci. U. S. A.