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Gyllenberg D, McKeague IW, Sourander A, Brown AS. Robust data-driven identification of risk factors and their interactions: A simulation and a study of parental and demographic risk factors for schizophrenia. Int J Methods Psychiatr Res 2020; 29:1-11. [PMID: 32520440 PMCID: PMC7723216 DOI: 10.1002/mpr.1834] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 03/12/2020] [Accepted: 04/29/2020] [Indexed: 01/01/2023] Open
Abstract
OBJECTIVES Few interactions between risk factors for schizophrenia have been replicated, but fitting all such interactions is difficult due to high-dimensionality. Our aims are to examine significant main and interaction effects for schizophrenia and the performance of our approach using simulated data. METHODS We apply the machine learning technique elastic net to a high-dimensional logistic regression model to produce a sparse set of predictors, and then assess the significance of odds ratios (OR) with Bonferroni-corrected p-values and confidence intervals (CI). We introduce a simulation model that resembles a Finnish nested case-control study of schizophrenia which uses national registers to identify cases (n = 1,468) and controls (n = 2,975). The predictors include nine sociodemographic factors and all interactions (31 predictors). RESULTS In the simulation, interactions with OR = 3 and prevalence = 4% were identified with <5% false positive rate and ≥80% power. None of the studied interactions were significantly associated with schizophrenia, but main effects of parental psychosis (OR = 5.2, CI 2.9-9.7; p < .001), urbanicity (1.3, 1.1-1.7; p = .001), and paternal age ≥35 (1.3, 1.004-1.6; p = .04) were significant. CONCLUSIONS We have provided an analytic pipeline for data-driven identification of main and interaction effects in case-control data. We identified highly replicated main effects for schizophrenia, but no interactions.
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Affiliation(s)
- David Gyllenberg
- Department of Child Psychiatry, University of Turku, Turku, Finland.,Department of Adolescent Psychiatry, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland.,Welfare Department, National Institute for Health and Welfare, Helsinki, Finland
| | - Ian W McKeague
- Department of Biostatistics, Columbia University Mailman School of Public Health, New York, New York, USA
| | - Andre Sourander
- Department of Child Psychiatry, University of Turku, Turku, Finland.,Department of Child Psychiatry, Turku University Central Hospital, Turku, Finland.,Department of Psychiatry, College of Physicians and Surgeons of Columbia University and New York State Psychiatric Institute, New York, New York, USA
| | - Alan S Brown
- Department of Psychiatry, College of Physicians and Surgeons of Columbia University and New York State Psychiatric Institute, New York, New York, USA.,Department of Epidemiology, Columbia University Mailman School of Public Health, New York, New York, USA
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Abstract
PURPOSE OF REVIEW We review recent developments on risk factors in schizophrenia. RECENT FINDINGS The way we think about schizophrenia today is profoundly different from the way this illness was seen in the twentieth century. We now know that the etiology of schizophrenia is multifactorial and reflects an interaction between genetic vulnerability and environmental contributors. Environmental risk factors such as pregnancy and birth complications, childhood trauma, migration, social isolation, urbanicity, and substance abuse, alone and in combination, acting at a number of levels over time, influence the individual's likelihood to develop the disorder. Environmental risk factors together with the identification of a polygenic risk score for schizophrenia, research on gene-environment interaction and environment-environment interaction have hugely increased our knowledge of the disorder.
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Affiliation(s)
- Simona A Stilo
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, De Crespigny Park, London, SE5 8AF, UK.
- National Institute for Health Research (NIHR) Mental Health Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King's College London, London, UK.
| | - Robin M Murray
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, De Crespigny Park, London, SE5 8AF, UK
- National Institute for Health Research (NIHR) Mental Health Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King's College London, London, UK
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3
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Smith KR. Paternal age bioethics. JOURNAL OF MEDICAL ETHICS 2015; 41:775-779. [PMID: 26037282 DOI: 10.1136/medethics-2014-102405] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 05/13/2015] [Indexed: 06/04/2023]
Abstract
Modern genetic sequencing studies have confirmed that the sperm of older men contain a greater number of de novo germline mutations than the sperm of younger men. Although most of these mutations are neutral or of minimal phenotypic impact, a minority of them present a risk to the health of future children. If demographic trends towards later fatherhood continue, this will likely lead to a more children suffering from genetic disorders. A trend of later fatherhood will accelerate the accumulation of paternal-origin de novo mutations in the gene pool, gradually reducing human fitness in the long term. These risks suggest that paternal age is of ethical importance. Children affected by de novo mutations arising from delayed fatherhood can be said to be harmed, in the sense of 'impersonal' harm or 'non-comparative' harm. Various strategies are open at societal and individual levels towards reducing deleterious paternal age effects. Options include health education to promote earlier fatherhood, incentives for young sperm donors and state-supported universal sperm banking. The latter approach would likely be of the greatest benefit and could in principle be implemented immediately. More futuristically, human germline genetic modification offers the potential to repair heritable mutational damage.
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Laurens KR, Luo L, Matheson SL, Carr VJ, Raudino A, Harris F, Green MJ. Common or distinct pathways to psychosis? A systematic review of evidence from prospective studies for developmental risk factors and antecedents of the schizophrenia spectrum disorders and affective psychoses. BMC Psychiatry 2015; 15:205. [PMID: 26302744 PMCID: PMC4548447 DOI: 10.1186/s12888-015-0562-2] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 07/14/2015] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND Identifying the unique and shared premorbid indicators of risk for the schizophrenia spectrum disorders (SSD) and affective psychoses (AP) may refine aetiological hypotheses and inform the delivery of universal versus targeted preventive interventions. This systematic review synthesises the available evidence concerning developmental risk factors and antecedents of SSD and AP to identify those with the most robust support, and to highlight remaining evidence gaps. METHODS A systematic search of prospective birth, population, high-risk, and case-control cohorts was conducted in Medline and supplemented by hand searching, incorporating published studies in English with full text available. Inclusion/exclusion decisions and data extraction were completed in duplicate. Exposures included three categories of risk factors and four categories of antecedents, with case and comparison groups defined by adult psychiatric diagnosis. Effect sizes and prevalence rates were extracted, where available, and the strength of evidence synthesised and evaluated qualitatively across the study designs. RESULTS Of 1775 studies identified by the search, 127 provided data to the review. Individuals who develop SSD experience a diversity of subtle premorbid developmental deficits and risk exposures, spanning the prenatal period through early adolescence. Those of greatest magnitude (or observed most consistently) included obstetric complications, maternal illness during pregnancy (especially infections), other maternal physical factors, negative family emotional environment, psychopathology and psychotic symptoms, and cognitive and motor dysfunctions. Relatively less evidence has accumulated to implicate this diversity of exposures in AP, and many yet remain unexamined, with the most consistent or strongest evidence to date being for obstetric complications, psychopathology, cognitive indicators and motor dysfunction. Among the few investigations affording direct comparison between SSD and AP, larger effect sizes and a greater number of significant associations are commonly reported for SSD relative to AP. CONCLUSIONS Shared risk factors for SSD and AP may include obstetric complications, childhood psychopathology, cognitive markers and motor dysfunction, but the capacity to distinguish common versus distinct risk factors/antecedents for SSD and AP is limited by the scant availability of prospective data for AP, and inconsistency in replication. Further studies considering both diagnoses concurrently are needed. Nonetheless, the prevalence of the risk factors/antecedents observed in cases and controls helps demarcate potential targets for preventative interventions for these disorders.
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Affiliation(s)
- Kristin R. Laurens
- Research Unit for Schizophrenia Epidemiology, School of Psychiatry, University of New South Wales, Sydney, Australia ,Schizophrenia Research Institute, Sydney, Australia ,Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London, UK ,Black Dog Institute, Prince of Wales Hospital, Sydney, Australia
| | - Luming Luo
- Research Unit for Schizophrenia Epidemiology, School of Psychiatry, University of New South Wales, Sydney, Australia. .,Schizophrenia Research Institute, Sydney, Australia.
| | - Sandra L. Matheson
- Research Unit for Schizophrenia Epidemiology, School of Psychiatry, University of New South Wales, Sydney, Australia ,Schizophrenia Research Institute, Sydney, Australia
| | - Vaughan J. Carr
- Research Unit for Schizophrenia Epidemiology, School of Psychiatry, University of New South Wales, Sydney, Australia ,Schizophrenia Research Institute, Sydney, Australia ,Department of Psychiatry, Monash University, Melbourne, Australia
| | - Alessandra Raudino
- Research Unit for Schizophrenia Epidemiology, School of Psychiatry, University of New South Wales, Sydney, Australia. .,Schizophrenia Research Institute, Sydney, Australia.
| | - Felicity Harris
- Research Unit for Schizophrenia Epidemiology, School of Psychiatry, University of New South Wales, Sydney, Australia. .,Schizophrenia Research Institute, Sydney, Australia.
| | - Melissa J. Green
- Research Unit for Schizophrenia Epidemiology, School of Psychiatry, University of New South Wales, Sydney, Australia ,Schizophrenia Research Institute, Sydney, Australia ,Black Dog Institute, Prince of Wales Hospital, Sydney, Australia ,Neuroscience Research Australia, Sydney, Australia
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Over-expression of XIST, the Master Gene for X Chromosome Inactivation, in Females With Major Affective Disorders. EBioMedicine 2015; 2:909-18. [PMID: 26425698 PMCID: PMC4563114 DOI: 10.1016/j.ebiom.2015.06.012] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 06/05/2015] [Accepted: 06/11/2015] [Indexed: 11/23/2022] Open
Abstract
Background Psychiatric disorders are common mental disorders without a pathological biomarker. Classic genetic studies found that an extra X chromosome frequently causes psychiatric symptoms in patients with either Klinefelter syndrome (XXY) or Triple X syndrome (XXX). Over-dosage of some X-linked escapee genes was suggested to cause psychiatric disorders. However, relevance of these rare genetic diseases to the pathogenesis of psychiatric disorders in the general population of psychiatric patients is unknown. Methods XIST and several X-linked genes were studied in 36 lymphoblastoid cell lines from healthy females and 60 lymphoblastoid cell lines from female patients with either bipolar disorder or recurrent major depression. XIST and KDM5C expression was also quantified in 48 RNA samples from postmortem human brains of healthy female controls and female psychiatric patients. Findings We found that the XIST gene, a master in control of X chromosome inactivation (XCI), is significantly over-expressed (p = 1 × 10− 7, corrected after multiple comparisons) in the lymphoblastoid cells of female patients with either bipolar disorder or major depression. The X-linked escapee gene KDM5C also displays significant up-regulation (p = 5.3 × 10− 7, corrected after multiple comparisons) in the patients' cells. Expression of XIST and KDM5C is highly correlated (Pearson's coefficient, r = 0.78, p = 1.3 × 10− 13). Studies on human postmortem brains supported over-expression of the XIST gene in female psychiatric patients. Interpretations We propose that over-expression of XIST may cause or result from subtle alteration of XCI, which up-regulates the expression of some X-linked escapee genes including KDM5C. Over-expression of X-linked genes could be a common mechanism for the development of psychiatric disorders between patients with those rare genetic diseases and the general population of female psychiatric patients with XIST over-expression. Our studies suggest that XIST and KDM5C expression could be used as a biological marker for diagnosis of psychiatric disorders in a significantly large subset of female patients. Research in context Due to lack of biological markers, diagnosis and treatment of psychiatric disorders are subjective. There is utmost urgency to identify biomarkers for clinics, research, and drug development. We found that XIST and KDM5C gene expression may be used as a biological marker for diagnosis of major affective disorders in a significantly large subset of female patients from the general population. Our studies show that over-expression of XIST and some X-linked escapee genes may be a common mechanism for development of psychiatric disorders between the patients with rare genetic diseases (XXY or XXX) and the general population of female psychiatric patients. XIST and KDM5C genes are over-expressed in a large subset of female patients with major affective disorders. Over-expression of XIST and KDM5C genes could be used as a biomarker for diagnosis of individual patients. Over-expression of XIST and X-linked escapee genes including KDM5C may cause major affective disorders.
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Malaspina D, Dracxler R, Walsh-Messinger J, Harlap S, Goetz RR, Keefe D, Perrin MC. Telomere length, family history, and paternal age in schizophrenia. Mol Genet Genomic Med 2014; 2:326-31. [PMID: 25077175 PMCID: PMC4113273 DOI: 10.1002/mgg3.71] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Revised: 01/20/2014] [Accepted: 01/29/2014] [Indexed: 01/07/2023] Open
Abstract
Leukocyte telomere length (LTL) is longer in association with advanced paternal age, but this association has not been examined along with family history (FH) in schizophrenia. LTL was measured by PCR and compared across cases and controls as part of a study to examine the characteristics of paternal age related schizophrenia. The 53 schizophrenia cases had similar mean LTL as 20 controls, although cases were significantly older than controls and overwhelmingly smoked cigarettes. Multivariate analyses showed that a FH of schizophrenia was associated with longer LTL in both male and female cases. Later paternal age was also related to longer LTL in male cases, but with shorter LTL in female cases. Male cases with older fathers and a FH had the longest LTL. The genetic architecture associated with a familial risk for schizophrenia may include pathways that lengthen LTL. Paternal aging conferred an additional increase in LTL lengthening in male cases, but reduced LTL in female cases. The gender difference in LTL for paternal aging is consistent with the severe illness features reported for female cases with older fathers and could implicate epigenetic alterations in the paternal X chromosomal region with advanced paternal age in association with the risk for schizophrenia.
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Affiliation(s)
- Dolores Malaspina
- Department of Psychiatry, Institute for Social and Psychiatric Initiatives, New York University School of Medicine New York, New York ; Creedmoor Psychiatric Center, NY State Office of Mental Health New York, New York
| | - Roberta Dracxler
- Department of Psychiatry, Institute for Social and Psychiatric Initiatives, New York University School of Medicine New York, New York ; Department of Obstetrics and Gynecology, New York University School of Medicine New York, New York
| | - Julie Walsh-Messinger
- Department of Psychiatry, Institute for Social and Psychiatric Initiatives, New York University School of Medicine New York, New York
| | - Susan Harlap
- Department of Psychiatry, Institute for Social and Psychiatric Initiatives, New York University School of Medicine New York, New York
| | - Raymond R Goetz
- Department of Psychiatry, Institute for Social and Psychiatric Initiatives, New York University School of Medicine New York, New York ; Division of Clinical Phenomenology, New York State Psychiatric Institute New York, New York
| | - David Keefe
- Department of Obstetrics and Gynecology, New York University School of Medicine New York, New York
| | - Mary C Perrin
- Department of Psychiatry, Institute for Social and Psychiatric Initiatives, New York University School of Medicine New York, New York
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Crow TJ. The XY gene hypothesis of psychosis: origins and current status. Am J Med Genet B Neuropsychiatr Genet 2013; 162B:800-24. [PMID: 24123874 PMCID: PMC4065359 DOI: 10.1002/ajmg.b.32202] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Accepted: 08/19/2013] [Indexed: 11/10/2022]
Abstract
Sex differences in psychosis and their interaction with laterality (systematic departures from 50:50 left-right symmetry across the antero-posterior neural axis) are reviewed in the context of the X-Y gene hypothesis. Aspects of laterality (handedness/cerebral asymmetry/the torque) predict (1) verbal and non-verbal ability in childhood and across adult life and (2) anatomical, physiological, and linguistic variation relating to psychosis. Neuropsychological and MRI evidence from individuals with sex chromosome aneuploidies indicates that laterality is associated with an X-Y homologous gene pair. Within each mammalian species the complement of such X-Y gene pairs reflects their potential to account for taxon-specific sexual dimorphisms. As a consequence of the mechanism of meiotic suppression of unpaired chromosomes such X-Y gene pairs generate epigenetic variation around a species defining motif that is carried to the zygote with potential to initiate embryonic gene expression in XX or XY format. The Protocadherin11XY (PCDH11XY) gene pair in Xq21.3/Yp11.2 in probable coordination with a gene or genes within PAR2 (the second pseudo-autosomal region) is the prime candidate in relation to cerebral asymmetry and psychosis in Homo sapiens. The lately-described pattern of sequence variation associated with psychosis on the autosomes may reflect a component of the human genome's adjustment to selective pressures generated by the sexually dimorphic mate recognition system.
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Affiliation(s)
- Timothy J Crow
- Department of Psychiatry, SANE POWIC, Warneford Hospital, University of OxfordOxford, UK
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Mura G, Petretto DR, Bhat KM, Carta MG. Schizophrenia: from epidemiology to rehabilitation. Clin Pract Epidemiol Ment Health 2012; 8:52-66. [PMID: 22962559 PMCID: PMC3434422 DOI: 10.2174/1745017901208010052] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2011] [Revised: 12/26/2011] [Accepted: 01/01/2012] [Indexed: 12/27/2022]
Abstract
Purpose/Objective: We discuss recent evidences about schizophrenia (frequency, onset, course, risk factors and genetics) and their influences to some epidemiological myths about schizophrenia diffuse between psychiatric and psychopathology clinicians. The scope is to evaluate if the new acquisitions may change the rehabilitation approaches to schizophrenia modifying the balance about the neurodevelopmental hypothesis of schizophrenia accepting that the cognitive deficits are produced by errors during the normal development of the brain (neurodevelopmental hypothesis) that remains stable in the course of illness and the neurodegenerative hypothesis according of which they derived from a degenerative process that goes on inexorably. Research Method/Design: A review of the literature about epidemiology of schizophrenia has been performed and the contributions of some of these evidence to neurodevelopmental hypothesis and to rehabilitation has been described. Results: It cannot be definitively concluded for or against the neurodevelopmental or degenerative hypothesis, but efforts in understanding basis of schizophrenia must go on. Until now, rehabilitation programs are based on the vulnerability-stress model: supposing an early deficit that go on stable during the life under favorable circumstances. So, rehabilitation approaches (as neuro-cognitive approaches, social skill training, cognitive-emotional training) are focused on the individual and micro-group coping skills, aiming to help people with schizophrenia to cope with environmental stress factors. Conclusions/Implications: Coping of cognitive deficits in schizophrenia may represents the starting-point for further research on schizophrenia, cohort studies and randomized trials are necessary to defined the range of effectiveness and the outcome of the treatments.
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Affiliation(s)
- Gioia Mura
- Consultation Liaison Psychiatric Unit at the University Hospital of Cagliari, University of Cagliari and AOU Cagliari - Italy
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Grigoroiu-Serbanescu M, Wickramaratne PJ, Mihailescu R, Prelipceanu D, Sima D, Codreanu M, Grimberg M, Elston RC. Paternal age effect on age of onset in bipolar I disorder is mediated by sex and family history. Am J Med Genet B Neuropsychiatr Genet 2012; 159B:567-79. [PMID: 22592928 DOI: 10.1002/ajmg.b.32063] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Accepted: 04/25/2012] [Indexed: 12/13/2022]
Abstract
This study investigated for the first time in the psychiatric literature the effect of parental age on age-of-onset (AO) in bipolar I disorder (BPI) in relation to proband sex and family history (FH) for major psychoses in a sample of 564 BPI probands. All probands, 72.68% of their first-degree and 12.13% of their second-degree relatives were directly interviewed. The FH-method was used for all unavailable relatives. The diagnoses were made according to DSM-IV(TR) . The impact of parental age on proband early/late AO was evaluated through logistic regression with the cut-off for early AO determined through commingling analysis. We found evidence for a significant influence of increasing paternal age, and especially age ≥ 35 years, on AO of BPI disorder in the total sample (OR = 0.54, CI: 0.35-0.80), in the female subsample (OR = 0.44, CI: 0.25-0.78), in the sporadic subsample (OR = 0.64, CI: 0.38-0.95), and in the subsample with FH of recurrent unipolar major depression (Mdd-RUP) (OR = 0.55, CI: 0.34-0.87). No significant effect of paternal age on disease AO was found in patients with FH of bipolar (BP), schizoaffective disorders (SA), or schizophrenia (SCZ), nor in males. Mean age was significantly higher in fathers of sporadic cases and of cases with FH of Mdd-RUP than in fathers of cases with FH of BP/SA/SCZ (P = 0.011). Maternal age had no significant effect either in the total sample or in subsamples defined by proband sex or FH. In conclusion, in our sample increasing paternal age lowered the onset of BPI selectively, the effect being related to the female sex and FH-type.
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Affiliation(s)
- Maria Grigoroiu-Serbanescu
- Biometric Psychiatric Genetics Research Unit, Alexandru Obregia Clinical Psychiatric Hospital, Bucharest, Romania.
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Frans EM, McGrath JJ, Sandin S, Lichtenstein P, Reichenberg A, Långström N, Hultman CM. Advanced paternal and grandpaternal age and schizophrenia: a three-generation perspective. Schizophr Res 2011; 133:120-4. [PMID: 22000939 PMCID: PMC3660090 DOI: 10.1016/j.schres.2011.09.027] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Revised: 09/13/2011] [Accepted: 09/18/2011] [Indexed: 12/16/2022]
Abstract
BACKGROUND Advanced paternal age has been linked with an increased risk of schizophrenia in the offspring. If age-related de novo mutations in the male germ line underlie this association, grandpaternal and paternal age would both be expected to influence the risk of schizophrenia. The aim of the current study was to explore the links between both paternal and grandpaternal age with respect to the risk of schizophrenia in a large, national register-based cohort. METHOD We linked the Swedish Multi-Generation and Hospital Discharge Registers and compared parents' ages at offspring birth for 20,582 schizophrenia-affected and 100,176 non-affected individuals. Grandparents' ages at the birth of the parent were compared between 2511 affected and 15,619 non-affected individuals. The risk of schizophrenia was examined with logistic regression when the predictor variable (parent or grandparent age) varied across age strata. RESULTS After adjusting for maternal age, birth year and proband sex, we confirmed that offspring of older fathers had an increased risk of schizophrenia. Compared to those with paternal age 20-24years, those with fathers >55years had a two-fold increased risk of schizophrenia. With respect to grandparent age, older maternal (but not paternal) grandfather age was associated with an increased risk of schizophrenia. Compared to maternal grandfather age 20-24years, those with maternal grandfathers >55years had a significantly increased risk of schizophrenia (adjusted odds ratio and 95% confidence intervals; 2.79, 1.71-4.56). The pattern of results was essentially unchanged when we examined male and female probands separately. CONCLUSION This is the first study to report an association between grandpaternal age and risk of schizophrenia. The selective effect of advanced maternal grandfather age suggests that the biological mechanisms involving the X-chromosome may differentially contribute to the association between paternal age and offspring risk of schizophrenia.
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Affiliation(s)
- Emma M. Frans
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet,Stockholm, Sweden
| | - John J. McGrath
- Queensland Centre for Mental Health Research, The Park Centre for Mental Health,Richlands, Australia,Queensland Brain Institute, The University of Queensland, St. Lucia, Australia,Department of Psychiatry, The University of Queensland, St. Lucia, Australia
| | - Sven Sandin
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet,Stockholm, Sweden
| | - Paul Lichtenstein
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet,Stockholm, Sweden
| | - Abraham Reichenberg
- Department of Psychosis Studies, Institute of Psychiatry, King’s Health Partners,King’s College London, London, UK,Department of Psychiatry, Mount Sinai School of Medicine, New York, NY, USA
| | - Niklas Långström
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet,Stockholm, Sweden,Centre for Violence Prevention, Karolinska Institutet, Stockholm, Sweden
| | - Christina M. Hultman
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet,Stockholm, Sweden
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Weissman MM, Brown AS, Talati A. Translational epidemiology in psychiatry: linking population to clinical and basic sciences. ACTA ACUST UNITED AC 2011; 68:600-8. [PMID: 21646577 DOI: 10.1001/archgenpsychiatry.2011.47] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Translational research generally refers to the application of knowledge generated by advances in basic sciences research translated into new approaches for diagnosis, prevention, and treatment of disease. This direction is called bench-to-bedside. Psychiatry has similarly emphasized the basic sciences as the starting point of translational research. This article introduces the term translational epidemiology for psychiatry research as a bidirectional concept in which the knowledge generated from the bedside or the population can also be translated to the benches of laboratory science. Epidemiologic studies are primarily observational but can generate representative samples, novel designs, and hypotheses that can be translated into more tractable experimental approaches in the clinical and basic sciences. This bedside-to-bench concept has not been explicated in psychiatry, although there are an increasing number of examples in the research literature. This article describes selected epidemiologic designs, providing examples and opportunities for translational research from community surveys and prospective, birth cohort, and family-based designs. Rapid developments in informatics, emphases on large sample collection for genetic and biomarker studies, and interest in personalized medicine--which requires information on relative and absolute risk factors--make this topic timely. The approach described has implications for providing fresh metaphors to communicate complex issues in interdisciplinary collaborations and for training in epidemiology and other sciences in psychiatry.
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Affiliation(s)
- Myrna M Weissman
- Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York State Psychiatric Institute, New York, NY 10032, USA.
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12
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Lee H, Malaspina D, Ahn H, Perrin M, Opler MG, Kleinhaus K, Harlap S, Goetz R, Antonius D. Paternal age related schizophrenia (PARS): Latent subgroups detected by k-means clustering analysis. Schizophr Res 2011; 128:143-9. [PMID: 21353765 PMCID: PMC3085629 DOI: 10.1016/j.schres.2011.02.006] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Revised: 02/04/2011] [Accepted: 02/07/2011] [Indexed: 11/21/2022]
Abstract
BACKGROUND Paternal age related schizophrenia (PARS) has been proposed as a subgroup of schizophrenia with distinct etiology, pathophysiology and symptoms. This study uses a k-means clustering analysis approach to generate hypotheses about differences between PARS and other cases of schizophrenia. METHODS We studied PARS (operationally defined as not having any family history of schizophrenia among first and second-degree relatives and fathers' age at birth ≥ 35 years) in a series of schizophrenia cases recruited from a research unit. Data were available on demographic variables, symptoms (Positive and Negative Syndrome Scale; PANSS), cognitive tests (Wechsler Adult Intelligence Scale-Revised; WAIS-R) and olfaction (University of Pennsylvania Smell Identification Test; UPSIT). We conducted a series of k-means clustering analyses to identify clusters of cases containing high concentrations of PARS. RESULTS Two analyses generated clusters with high concentrations of PARS cases. The first analysis (N=136; PARS=34) revealed a cluster containing 83% PARS cases, in which the patients showed a significant discrepancy between verbal and performance intelligence. The mean paternal and maternal ages were 41 and 33, respectively. The second analysis (N=123; PARS=30) revealed a cluster containing 71% PARS cases, of which 93% were females; the mean age of onset of psychosis, at 17.2, was significantly early. CONCLUSIONS These results strengthen the evidence that PARS cases differ from other patients with schizophrenia. Hypothesis-generating findings suggest that features of PARS may include a discrepancy between verbal and performance intelligence, and in females, an early age of onset. These findings provide a rationale for separating these phenotypes from others in future clinical, genetic and pathophysiologic studies of schizophrenia and in considering responses to treatment.
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Affiliation(s)
- Hyejoo Lee
- Department of Applied Mathematics and Statistics, Stony Brook University, Stony Brook, NY, USA
| | - Dolores Malaspina
- Institute for Social and Psychiatric Initiatives (InSPIRES), Department of Psychiatry, New York University School of Medicine, New York, NY, USA
| | - Hongshik Ahn
- Department of Applied Mathematics and Statistics, Stony Brook University, Stony Brook, NY, USA
| | - Mary Perrin
- Institute for Social and Psychiatric Initiatives (InSPIRES), Department of Psychiatry, New York University School of Medicine, New York, NY, USA
| | - Mark G. Opler
- Institute for Social and Psychiatric Initiatives (InSPIRES), Department of Psychiatry, New York University School of Medicine, New York, NY, USA
| | - Karine Kleinhaus
- Institute for Social and Psychiatric Initiatives (InSPIRES), Department of Psychiatry, New York University School of Medicine, New York, NY, USA
| | - Susan Harlap
- Institute for Social and Psychiatric Initiatives (InSPIRES), Department of Psychiatry, New York University School of Medicine, New York, NY, USA
| | - Raymond Goetz
- Institute for Social and Psychiatric Initiatives (InSPIRES), Department of Psychiatry, New York University School of Medicine, New York, NY, USA
- Department of Psychiatry, Columbia University, New York State Psychiatric Institute, New York, NY, USA
| | - Daniel Antonius
- Institute for Social and Psychiatric Initiatives (InSPIRES), Department of Psychiatry, New York University School of Medicine, New York, NY, USA
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