Advanced paternal age increases the risk of schizophrenia and obsessive-compulsive disorder in a Chinese Han population

Building a family at advanced parental age: a systematic review on the risks and opportunities for parents and their offspring

STUDY QUESTION

What is the existing empirical literature on the psychosocial health and wellbeing of the parents and offspring born at an advanced parental age (APA), defined as 40 years onwards?

SUMMARY ANSWER

Although the studies show discrepancies in defining who is an APA parent and an imbalance in the empirical evidence for offspring, mothers, and fathers, there is a drive towards finding psychotic disorders and (neuro-)developmental disorders among the offspring; overall, the observed advantages and disadvantages are difficult to compare.

WHAT IS KNOWN ALREADY

In many societies, children are born to parents at advanced ages and there is rising attention in the literature towards the consequences of this trend.

STUDY DESIGN SIZE DURATION

The systematic search was conducted in six electronic databases (PubMed including Medline, Embase, Scopus, PsycInfo, CINAHL, and SocINDEX) and was limited to papers published between 2000 and 2021 and to English-language articles. Search terms used across all six electronic databases were: ('advanced parental age' OR 'advanced maternal age' OR 'advanced paternal age' OR 'advanced reproductive age' OR 'late parent*' OR 'late motherhood' OR 'late fatherhood') AND ('IVF' OR 'in vitro fertilization' OR 'in-vitro-fertilization' OR 'fertilization in vitro' OR 'ICSI' OR 'intracytoplasmic sperm injection' OR 'reproductive techn*' OR 'assisted reproductive technolog*' OR 'assisted reproduction' OR 'assisted conception' OR 'reproduction' OR 'conception' OR 'birth*' OR 'pregnan*') AND ('wellbeing' OR 'well-being' OR 'psycho-social' OR 'social' OR 'ethical' OR 'right to reproduce' OR 'justice' OR 'family functioning' OR 'parental competenc*' OR 'ageism' OR 'reproductive autonomy' OR 'outcome' OR 'risk*' OR 'benefit*').

PARTICIPANTS/MATERIALS SETTING METHODS

The included papers were empirical studies in English published between 2000 and 2021, where the study either examined the wellbeing and psychosocial health of parents and/or their children, or focused on parental competences of APA parents or on the functioning of families with APA parents. A quality assessment of the identified studies was performed with the QATSDD tool. Additionally, 20% of studies were double-checked at the data extraction and quality assessment stage to avoid bias. The variables sought were: the geographical location, the year of publication, the methodological approach, the definitions of APA used, what study group was at the centre of the research, what research topic was studied, and what advantages and disadvantages of APA were found.

MAIN RESULTS AND THE ROLE OF CHANCE

A total number of 5403 articles were identified, leading to 2543 articles being included for title and abstract screening after removal of duplicates. This resulted in 98 articles included for a full-text reading by four researchers. Ultimately, 69 studies were included in the final sample. The key results concerned four aspects relevant to the research goals. (i) The studies showed discrepancies in defining who is an APA parent. (ii) There was an imbalance in the empirical evidence produced for different participant groups (mothers, fathers, and offspring), with offspring being the most studied study subjects. (iii) The research topics studied underlined the increased risks of neuro-developmental and psychotic disorders among offspring. (iv) The observed advantages and disadvantages were varied and could not be compared, especially for the offspring of APA parents.

LIMITATIONS REASONS FOR CAUTION

Only English-language studies, published between 2000 and 2021, found in the above-mentioned databases were considered for this review.

WIDER IMPLICATIONS OF THE FINDINGS

More research is necessary to understand the risks and benefits of building a family at an APA for the offspring when they reach adulthood. Furthermore, studies that explore the perspective of older fathers and older parents from non-Western societies would be highly informative.

STUDY FUNDING/COMPETING INTERESTS

The writing of this manuscript was permitted by financial support provided by the Swiss National Science Foundation (Weave/Lead Agency funding program, grant number 10001AL_197415/1, project title 'Family Building at Advanced Parental Age: An Interdisciplinary Approach'). The funder had no role in the drafting of this manuscript and the views expressed therein are those of the authors. The authors have no conflicts of interest.

REGISTRATION NUMBER

This systematic review is registered in Prospero: CRD42022304564.

Impact of paternal age on assisted reproductive technology outcomes and offspring health: a systematic review

BACKGROUND

The increase in paternal age and the percentage of births after assisted reproductive technologies (ART) may have consequences on offspring and society's position regarding access to ART must be questioned. Most countries recommend limiting ART to men under 60 years. What is the rationale for this threshold?

OBJECTIVE

This systematic review assesses scientific arguments to establish links between paternal age, male fertility, and offspring health.

MATERIAL AND METHODS

Using the PRISMA guidelines, this systematic review of the literature analyzed 111 articles selected after screening PubMed, ScienceDirect, and Web of Science for articles published between January 1, 1995 and December 31, 2021.

RESULTS

A strong correlation was highlighted between advanced paternal age and a decrease of some sperm parameters (semen volume and sperm motility) and infant morbidity (exponentially increased incidence of achondroplasia and Apert syndrome, and more moderately increased incidence of autism and schizophrenia). The impact of paternal age on pregnancy and fetal aneuploidy rates is more controversial. No association was found with spontaneous abortion rates.

DISCUSSION AND CONCLUSION

The scientific parameters should be explained to older parents undergoing ART. And for countries that discuss a limit on paternal age for access to ART, the debate requires consideration of social and ethical arguments.

Paternal age and specific neurological soft signs as reliable and valid neurobiological markers for the diagnosis of patients with schizophrenia

Advanced parental age at delivery and neurological soft signs (NSS) constitute risk factors for schizophrenia. The aim of the current study was to develop a neurobiological diagnostic index by combining them, and without the contribution of clinical symptomatology. The study sample included 133 patients suffering from schizophrenia according to DSM-IV-TR (77 males and 56 females; aged 33.55 ± 11.22 years old) and 122 normal controls (66 males and 56 females; aged 32.89 ± 9.91 years old). The assessment included the Neurological Evaluation Scale (NES), and a number of scales assessing the clinical symptoms and adverse effects. The statistical analysis included exploratory t-test, Pearson Correlation coefficient (R) and Discriminant Function Analysis (DFA). Exploratory t-tests and Pearson's R suggested that sex, parental age and NSS constitute independent components. On the basis of DFA results, the Psychotic Neurological Index was developed. At the cut-off PNI score of 8.5, sensitivity was equal to 94.74 and specificity to 93.44. The current is probably the first study to report on an easily obtainable diagnostic neurobiological marker with identifiable properties which is absolutely independent from the clinical manifestations and could serve in distinguishing between patients with schizophrenia and healthy controls with high efficacy.

Effect of advanced parental age on pregnancy outcome and offspring health

PURPOSE

Fertility at advanced age has become increasingly common, but the aging of parents may adversely affect the maturation of gametes and the development of embryos, and therefore the effects of aging are likely to be transmitted to the next generation. This article reviewed the studies in this field in recent years.

METHODS

We searched the relevant literature in recent years with the keywords of "advanced maternal/paternal age" combined with "adverse pregnancy outcome" or "birth defect" in the PubMed database and classified the effects of parental advanced age on pregnancy outcomes and birth defects. Related studies on the effect of advanced age on birth defects were classified as chromosomal abnormalities, neurological and psychiatric disorders, and other systemic diseases. The effect of assisted reproduction technology (ART) on fertility in advanced age was also discussed.

RESULTS

Differences in the definition of the range of advanced age and other confounding factors among studies were excluded, most studies believed that advanced parental age would affect pregnancy outcomes and birth defects in offspring.

CONCLUSION

To some extent, advanced parental age caused adverse pregnancy outcomes and birth defects. The occurrence of these results was related to the molecular genetic changes caused by aging, such as gene mutations, epigenetic variations, etc. Any etiology of adverse pregnancy outcomes and birth defects related to aging might be more than one. The detrimental effect of advanced age can be corrected to some extent by ART.

Reprint of: Advanced paternal age and risk of schizophrenia in offspring - Review of epidemiological findings and potential mechanisms

A large number of studies have examined the association between advanced paternal age (APA) and risk of schizophrenia in offspring. Here we present an overview of epidemiological studies on this subject published since 2000, and systematically summarize their methodologies and results. Next, we discuss evidence to elucidate the potential mechanisms contributing to the association between APA and offspring schizophrenia, considering paternal psychiatric morbidity and genetic liability, maternal factors, and findings from family design studies. We propose that multiple mechanisms, including causal and non-causal pathways, contribute to the observed relationship between APA and schizophrenia in offspring, and conclude by highlighting the need for multi-disciplinary studies in disentangling these complex, non-mutually exclusive mechanisms.

Paternal ageing impacts blastulation and the outcomes of pregnancy at different levels of maternal age: A clustering analysis of 21,960 oocytes and 3837 ICSI cycles

The objective of this cross-sectional study was to investigate the impact of paternal age on the outcomes of intracytoplasmic sperm injection (ICSI) cycles at different values of maternal age. A total of 21,960 injected oocytes deriving from 3837 ICSI cycles performed between January 2014 and October 2020, performed in a private university-affiliated in vitro fertilization centre was included. The main effects of maternal and paternal age, as well as the effect of their product (interaction term) on embryo development and pregnancy outcomes were investigated considering the clustering of data. The coefficients for the interaction term were statistically significant for blastocyst development, top-quality blastocyst, implantation, pregnancy, miscarriage, and live-birth rates. For every 1-year increase in paternal age, the odds ratio of live-birth reduces by 1% in females aged 37 years, 1.6% in those aged 38 years, 2.4% in 39-year-old females, 5% in 42-year-old females and so on. An increase in the interaction term by 1 year decreases the pregnancy rate by 0.4% and live-birth rate by 0.8 and increases the miscarriage rate by 1.2%. The slopes of maternal age on blastulation, blastocyst quality, and implantation, pregnancy, miscarriage, and live-birth rate significantly changed (worsened) for every year increase in paternal age.

Advanced Paternal Age and Future Generations

Paternal age at conception has been increasing. In this review, we first present the results from the major mammalian animal models used to establish that increasing paternal age does affect progeny outcome. These models provide several major advantages including the possibility to assess multi- transgenerational effects of paternal age on progeny in a relatively short time window. We then present the clinical observations relating advanced paternal age to fertility and effects on offspring with respect to perinatal health, cancer risk, genetic diseases, and neurodevelopmental effects. An overview of the potential mechanism operating in altering germ cells in advanced age is presented. This is followed by an analysis of the current state of management of reproductive risks associated with advanced paternal age. The numerous challenges associated with developing effective, practical strategies to mitigate the impact of advanced paternal age are outlined along with an approach on how to move forward with this important clinical quandary.

The role of early-life family composition and parental socio-economic status as risk factors for obsessive-compulsive disorder in a Danish national cohort

Research on early-life family environment on obsessive-compulsive disorder (OCD) risk is limited, and sex differences have not been sufficiently studied. We investigated early-life family composition and parental socio-economic status (SES) as OCD risk factors while stratifying for sex in a sample of 1,154,067 individuals from the Danish population (7550 of whom had OCD). Data on early-life family composition (birth order, number of siblings, number of parents in household at proband age 6), parental SES at age 6 (parental income, occupation, and education level), history of parental psychiatric illness, and parental age at birth on OCD risk (i.e., an ICD-10 diagnosis of F42.x) were obtained from Danish population registers. Survival analyses using Cox regression were performed with age as the underlying time variable. Analyses were adjusted for calendar time, and differential effect by sex was tested for exposures. We found that birth order and advanced maternal age were risk factors for OCD in males, and being an only child was associated with increased OCD risk in both sexes. Early childhood SES variables including parental education, occupation, and income were associated with OCD risk, and these effects were more pronounced in females. Significant interaction effects for parental education/occupation and the presence of non-OCD psychiatric diagnoses in the proband also emerged. Our results suggest that early-life SES and family composition may be important risk factors for OCD, and heterogeneity in OCD cases in terms of psychiatric comorbidities, as well as sex differences should be carefully examined in relation to risk factors.

A multifactorial model for the etiology of neuropsychiatric disorders: the role of advanced paternal age

Mental or neuropsychiatric disorders are widespread within our societies affecting one in every four people in the world. Very often the onset of a mental disorder (MD) occurs in early childhood and substantially reduces the quality of later life. Although the global burden of MDs is rising, mental health care is still suboptimal, partly due to insufficient understanding of the processes of disease development. New insights are needed to respond to this worldwide health problem. Next to the growing burden of MDs, there is a tendency to postpone pregnancy for various economic and practical reasons. In this review, we describe the current knowledge on the potential effect from advanced paternal age (APA) on development of autism spectrum disorder, schizophrenia, attention-deficit/hyperactivity disorder, bipolar disorder, obsessive-compulsive disorder, and Tourette syndrome. Although literature did not clearly define an age cut-off for APA, we here present a comprehensive multifactorial model for the development of MDs, including the role of aging, de novo mutations, epigenetic mechanisms, psychosocial environment, and selection into late fatherhood. Our model is part of the Paternal Origins of Health and Disease paradigm and may serve as a foundation for future epidemiological research designs. This blueprint will increase the understanding of the etiology of MDs and can be used as a practical guide for clinicians favoring early detection and developing a tailored treatment plan. Ultimately, this will help health policy practitioners to prevent the development of MDs and to inform health-care workers and the community about disease determinants. Better knowledge of the proportion of all risk factors, their interactions, and their role in the development of MDs will lead to an optimization of mental health care and management. IMPACT: We design a model of causation for MDs, integrating male aging, (epi)genetics, and environmental influences. It adds new insights into the current knowledge about associations between APA and MDs. In clinical practice, this comprehensive model may be helpful in early diagnosis and in treatment adopting a personal approach. It may help in identifying the proximate cause on an individual level or in a specific subpopulation. Besides the opportunity to measure the attributed proportions of risk factors, this model may be used as a blueprint to design prevention strategies for public health purposes.

Behavioural and cognitive behavioural therapy for obsessive compulsive disorder (OCD) in individuals with autism spectrum disorder (ASD)

BACKGROUND

Autistic spectrum disorder (ASD) is an increasingly recognised neurodevelopmental condition; that is, a neurologically-based condition which interferes with the acquisition, retention or application of specific skills. ASD is characterised by challenges with socialisation and communication, and by stereotyped and repetitive behaviours. A stereotyped behaviour is one which is repeated over and over again and which seems not to have any useful function. ASD often co-occurs with mental health disorders, including obsessive compulsive disorder (OCD). People with ASD may show certain cognitive differences (i.e. differences in ways of thinking) which influence their response to therapies. Thus, there is a need for evidence-based guidelines to treat mental health issues in this group. OCD, a common condition characterised by repeated obsessional thoughts and compulsive acts, occurs with greater frequency in persons with ASD than in the general population. Genetic, anatomic, neurobiological and psychological factors have been proposed to explain this co-occurrence. However, care should be taken to distinguish stereotyped and repetitive behaviours characteristic of ASD from obsessive compulsive acts in OCD. Cognitive behavioural therapy (CBT) is the recommended treatment for OCD, but studies have suggested that this treatment may be less effective in those with OCD co-occurring with ASD. Hence, modifications to CBT treatment may be helpful when treating OCD co-occurring with ASD to optimise outcomes.

OBJECTIVES

To assess the effectiveness of behavioural and cognitive behavioural therapy for obsessive compulsive disorder (OCD) in children and adults with autism spectrum disorder (ASD).

SEARCH METHODS

We searched for studies in the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, PsycINFO, five other bibliographic databases, international trial registries and other sources of grey literature (to 24 August 2020). We checked the reference lists of included studies and relevant systematic reviews to identify additional studies missed from the original electronic searches. We contacted subject experts for further information when needed.

SELECTION CRITERIA

We included randomised controlled trials (RCTs), cross-over, cluster- and quasi-randomised controlled trials involving both adults and children with diagnoses of OCD and ASD. We included studies of participants with co-occurring conditions (i.e. those experiencing other mental illnesses or neurodevelopmental conditions at the same time), but we did not include individuals who had a co-occurring global learning difficulty. Treatment could be in any setting or format and include behavioural therapy (BT) and cognitive behavioural therapy (CBT), which may have been adapted for those with ASD. Comparator interventions included no treatment, waiting list, attention placebo (where the control group receives non-specific aspects of therapy, but not the active ingredient) and treatment as usual (TAU, where the control group receives the usual treatment, according to accepted standards).

DATA COLLECTION AND ANALYSIS

Three review authors independently screened studies for inclusion. The authors extracted relevant data from the one eligible study, assessed the risk of bias and certainty of evidence (GRADE). Outcomes of interest were changes in OCD symptoms and treatment completion (primary outcome), and severity of depressive symptoms, anxiety symptoms and behavioural difficulties, as well as degree of family accommodation (secondary outcomes). We did not conduct meta-analyses as only one study met the selection criteria.

MAIN RESULTS

We included only one RCT of 46 participants in our analysis. This study compared CBT for OCD in persons with high-functioning ASD with a control group who received anxiety management only. There were no differences in rates of treatment completion between the CBT (87%) and anxiety management (87%) groups (risk ratio (RR) 1.00, 95% confidence interval (CI) 0.80 to 1.25; low-certainty evidence). Behavioural difficulties were not included as an outcome measure in the study. This study showed that there may be a benefit at the end of treatment favouring CBT compared with anxiety management in OCD symptoms (mean difference (MD) -3.00, 95% CI -8.02 to 2.02), depression symptoms (MD -1.80, 95% CI -11.50 to 7.90), anxiety symptoms (MD -3.20, 95% CI -11.38 to 4.98), and quality of life (MD 5.20, 95% CI -1.41 to 11.81), but the evidence was of low certainty.  AUTHORS' CONCLUSIONS: Evidence is limited regarding the efficacy of CBT for treatment of OCD in ASD. There is much scope for future study, not only examining the efficacy of CBT for OCD in ASD, but also the particular ways that OCD manifests in and affects people with ASD and the role of the family in treatment response.

Advanced paternal age and risk of schizophrenia in offspring - Review of epidemiological findings and potential mechanisms

A large number of studies have examined the association between advanced paternal age (APA) and risk of schizophrenia in offspring. Here we present an overview of epidemiological studies on this subject published since 2000, and systematically summarize their methodologies and results. Next, we discuss evidence to elucidate the potential mechanisms contributing to the association between APA and offspring schizophrenia, considering paternal psychiatric morbidity and genetic liability, maternal factors, and findings from family design studies. We propose that multiple mechanisms, including causal and non-causal pathways, contribute to the observed relationship between APA and schizophrenia in offspring, and conclude by highlighting the need for multi-disciplinary studies in disentangling these complex, non-mutually exclusive mechanisms.

The other face of advanced paternal age: a scoping review of its terminological, social, public health, psychological, ethical and regulatory aspects

BACKGROUND

There is a global tendency for parents to conceive children later in life. The maternal dimension of the postponement transition has been thoroughly studied, but interest in the paternal side is more recent. For the moment, most literature reviews on the topic have focused on the consequences of advanced paternal age (APA) on fertility, pregnancy and the health of the child.

OBJECTIVE AND RATIONALE

The present review seeks to move the focus away from the biological and medical dimensions of APA and synthesise the knowledge of the other face of APA.

SEARCH METHODS

We used the scoping review methodology. Searches of interdisciplinary articles databases were performed with keywords pertaining to APA and its dimensions outside of biology and medicine. We included scientific articles, original research, essays, commentaries and editorials in the sample. The final sample of 177 documents was analysed with qualitative thematic analysis.

OUTCOMES

We identified six themes highlighting the interdisciplinary nature of APA research. The 'terminological aspects' highlight the lack of consensus on the definition of APA and the strategies developed to offer alternatives. The 'social aspects' focus on the postponement transition towards reproducing later in life and its cultural dimensions. The 'public health aspects' refer to attempts to analyse APA as a problem with wider health and economic implications. The 'psychological aspects' focus on the consequences of APA and older fatherhood on psychological characteristics of the child. The 'ethical aspects' reflect on issues of APA emerging at the intersection of parental autonomy, children's welfare and social responsibility. The 'regulatory aspects' group different suggestions to collectively approach the implications of APA. Our results show that the field of APA is still in the making and that evidence is lacking to fully address the issues of APA. The review suggests promising avenues of research such as introducing the voice of fathers of advanced age into the research agenda.

WIDER IMPLICATIONS

The results of this review will be useful for developing policies and preconception health interventions that consider and include prospective fathers of advanced age.

Nordic OCD & Related Disorders Consortium: Rationale, design, and methods

Obsessive-compulsive disorder (OCD) is a debilitating psychiatric disorder, yet its etiology is unknown and treatment outcomes could be improved if biological targets could be identified. Unfortunately, genetic findings for OCD are lagging behind other psychiatric disorders. Thus, there is a pressing need to understand the causal mechanisms implicated in OCD in order to improve clinical outcomes and to reduce morbidity and societal costs. Specifically, there is a need for a large-scale, etiologically informative genetic study integrating genetic and environmental factors that presumably interact to cause the condition. The Nordic countries provide fertile ground for such a study, given their detailed population registers, national healthcare systems and active specialist clinics for OCD. We thus formed the Nordic OCD and Related Disorders Consortium (NORDiC, www.crowleylab.org/nordic), and with the support of NIMH and the Swedish Research Council, have begun to collect a large, richly phenotyped and genotyped sample of OCD cases. Our specific aims are geared toward answering a number of key questions regarding the biology, etiology, and treatment of OCD. This article describes and discusses the rationale, design, and methodology of NORDiC, including details on clinical measures and planned genomic analyses.

A cross sectional study of impact and clinical risk factors of antipsychotic-induced OCD

A large proportion of schizophrenia patients treated with second generation antipsychotics will develop Obsessive Compulsive Disorder (OCD). However, there are few studies about the impact of this comorbidity and who is at higher risk. In this study of clozapine-treated patients, we aimed to determine the impact on outcome of clozapine-induced OCD, as well as the clinical and sociodemographic risk factors related to OCD-onset in clozapine patients. We had strict and novel inclusion criteria to minimise mis-identification of cases. The Obsessive-Compulsive Inventory-Revised (OCI-R) was used to divide 231 clozapine-treated patients into extreme cases of OCD (OCI  ≥ 24 or checking subscale ≥6) versus non-OCD (OCI <15 and checking subscale <4). The Global Assessment of Functioning (GAF), short version of Warwick-Edinburgh Wellbeing scale and Clinical Global Impression for schizophrenia (CGI) scales were used to determine outcome. Socio-demographic information was used to identify the risk factors for OCD development. We found that schizophrenia patients with OCD symptoms had a significantly lower patient rated wellbeing scores (p < 0.001) only (no difference in clinician rated wellbeing scores), higher CGI positive (p < 0.01) and higher CGI depressive scores (p < 0.05). The only risk factors that reached significance level were higher treatment dose (p < 0.01) and younger paternal age at birth (p < 0.05). There is scope for future studies based on e.g. imaging and genetic studies to further investigate causality, and in improving clinician screening for OCD.

A case-control study of paternal and maternal age as risk factors in mood disorders

Objective: Advanced parental age might constitute a risk factor for various disorders. We tested whether this concerns also mood disorder patients. Methods: The study included 314 subjects (42 bipolar-BD patients; 21 manics and 21 depressives, 68 unipolar-UD, and 204 normal controls-NC). Analysis of Covariance (ANCOVA) and the calculation of the Relative Risk (RR) and the Odds Ratio (OR) were used for the analysis. Results: Paternal age differed between NC and UD patients (29.42 ± 6.07 vs. 32.12 ± 5.54; p = .01) and manics (29.42 ± 6.07 vs. 35.00 ± 5.75; p = .001) and maternal age between NC and manics (25.46 ± 4.52 vs. 31.43 ± 4.75; p < .001) and manic and UD (31.43 ± 4.75 vs. 26.75 ± 6.03; p = .002). The RR and OR values suggested that advanced parental age constitutes a risk factor for the development of mood disorders. Conclusions: In a non-dose dependent and gender-independent, advanced parental age constitutes a risk factor for the development of BD with index episode of mania (probably manic predominant polarity); only advanced paternal age constitutes a risk factor for the development of UD and BD with index episode of depression (probably depressive predominant polarity). This is the first study suggesting differential effect of advanced parental age depending on predominant polarity of BD.

Parental characteristics and the risk of schizophrenia in a Chinese population: a case-control study

BACKGROUND

Genetic studies have provided convergent results indicating that schizophrenia is a polygenic disorder with a heritability estimate of ∼60-80%. The propensity for schizophrenia is ∼10 times higher in individuals with first-degree relatives with schizophrenia when compared to the general population.

AIM

To identify associations between parental characteristics and the risk of schizophrenia in a Chinese population.

METHODS

Participants with a diagnosis of schizophrenia were recruited along with healthy controls (HCs) matched for age and gender from Weifang, China. Logistic regression models and generalized linear models were used to explore the associations between parental characteristics with the risk and age at onset of schizophrenia. In total, 414 cases and 639 HCs were recruited for the study.

RESULTS

We observed an inverse association between levels of paternal and maternal education and risk of schizophrenia after controlling for potential confounders (Paternal: OR = 1.525, 95% CI: 1.080-2.153, p = .017; Maternal: OR = 1.984, 95% CI: 1.346-2.924, p = .001). Younger paternal and maternal childbearing age were associated with a higher risk of diagnosis of schizophrenia. We furtherly observed that individuals with earlier age at onset of schizophrenia had fewer siblings (p = .007) and had higher rates of parental marital disharmony (p = .033).

CONCLUSION

Our results indicate that parental years of education and age of childbearing are associated with an increased risk of schizophrenia in a Chinese population. Age of onset of schizophrenia was positively associated with a greater number of siblings and negatively associated with parental marital disharmony.

Challenges in the diagnosis and treatment of pediatric obsessive-compulsive disorder

Obsessive-compulsive disorder (OCD) affects 1%-3% of children worldwide and has a profound impact on quality of life for patients and families. Although our understanding of the underlying etiology remains limited, data from neuroimaging and genetic studies as well as the efficacy of serotonergic medications suggest the disorder is associated with the fundamental alterations in the function of cortico-striato-thalamocortical circuits. Significant delays to diagnosis are common, ultimately leading to more severe functional impairment with long-term developmental consequences. The clinical assessment requires a detailed history of specific OCD symptoms as well as psychiatric and medical comorbidities. Standardized assessment tools may aid in evaluating and tracking symptom severity and both individual and family functioning. In the majority of children, an interdisciplinary approach that combines cognitive behavioral therapy with a serotonin reuptake inhibitor leads to meaningful symptom improvement, although some patients experience a chronic, episodic course. There are limited data to guide the management of treatment-refractory illness in children, although atypical antipsychotics and glutamate-modulating agents may be used cautiously as augmenting agents. This review outlines a clinical approach to the diagnosis and management of OCD, highlighting associated challenges, and limitations to our current knowledge.

The effect of paternal factors on perinatal and paediatric outcomes: a systematic review and meta-analysis

BACKGROUND

Maternal factors, including increasing childbearing age and various life-style factors, are associated with poorer short- and long-term outcomes for children, whereas knowledge of paternal parameters is limited. Recently, increasing paternal age has been associated with adverse obstetric outcomes, birth defects, autism spectrum disorders and schizophrenia in children.

OBJECTIVE AND RATIONALE

The aim of this systematic review is to describe the influence of paternal factors on adverse short- and long-term child outcomes.

SEARCH METHODS

PubMed, Embase and Cochrane databases up to January 2017 were searched. Paternal factors examined included paternal age and life-style factors such as body mass index (BMI), adiposity and cigarette smoking. The outcome variables assessed were short-term outcomes such as preterm birth, low birth weight, small for gestational age (SGA), stillbirth, birth defects and chromosomal anomalies. Long-term outcome variables included mortality, cancers, psychiatric diseases/disorders and metabolic diseases. The systematic review follows PRISMA guidelines. Relevant meta-analyses were performed.

OUTCOMES

The search included 14 371 articles out of which 238 met the inclusion criteria, and 81 were included in quantitative synthesis (meta-analyses). Paternal age and paternal life-style factors have an association with adverse outcome in offspring. This is particularly evident for psychiatric disorders such as autism, autism spectrum disorders and schizophrenia, but an association is also found with stillbirth, any birth defects, orofacial clefts and trisomy 21. Paternal height, but not BMI, is associated with birth weight in offspring while paternal BMI is associated with BMI, weight and/or body fat in childhood. Paternal smoking is found to be associated with an increase in SGA, birth defects such as congenital heart defects, and orofacial clefts, cancers, brain tumours and acute lymphoblastic leukaemia. These associations are significant although moderate in size, with most pooled estimates between 1.05 and 1.5, and none exceeding 2.0.

WIDER IMPLICATIONS

Although the increased risks of adverse outcome in offspring associated with paternal factors and identified in this report represent serious health effects, the magnitude of these effects seems modest.

Paternal and maternal age as risk factors for schizophrenia: a case-control study

OBJECTIVE

Advanced parental age might constitute a generic risk factor for mental and somatic disorders. The current study tested whether this concerns also patients with schizophrenia.

METHODS

A total of 231 schizophrenic, 56 other severe mental disorders patients and 204 controls were diagnosed according to DSM-IV-TR. Data were tested with ANOVA models including relative risk and odds ratios.

RESULTS

Patients with schizophrenia manifested higher paternal (32.55 ± 6.35 vs. 29.42 ± 6.07, p < .001) and maternal age (27.66 ± 5.57 vs. 25.46 ± 4.52, p < .001). Patients with other mental disorders had higher paternal (33.29 ± 8.35; p = .001) but not maternal age (26.69 ± 5.89; p = .296) compared to controls. There was no difference between the two patient groups concerning either paternal or maternal age (p > .05). There seems to be a higher risk for the development of schizophrenia in offspring with paternal age above 25 years and maternal age above 22 years at delivery.

CONCLUSIONS

The current study provides further support for the suggestion that advanced paternal age constitutes a risk factor (in a non-dose dependent and gender-independent way) for the development of schizophrenia but also for other mental disorders. In contrast, advanced maternal age characterises schizophrenia specifically. The higher risk is evident after 25 years of paternal and 22 years of maternal age, respectively.

Parental age and the risk of obsessive compulsive disorder and Tourette syndrome / chronic tic disorder in a nationwide population-based sample

OBJECTIVES

Advancing paternal age has been associated with several neuropsychiatric disorders in children. However, there is limited understanding of this association with obsessive compulsive disorder (OCD) and Tourette syndrome/chronic tic disorder (TS/CT) with inconsistent findings. We examined the association between parental age and offspring OCD and TS/CT.

METHODS

This nested case-control study used the Finnish Hospital Discharge Register (FHDR) to identify 1358 individuals with OCD and 1195 with TS/CT, born from 1991 to 2009 and diagnosed by 2010. Each case was matched with four controls from the Finnish Population Register (FPR), without diagnoses of OCD, TS/CT or severe or profound mental retardation. Conditional logistic regression was used to examine the association between parental age and OCD, TS/CT.

RESULTS

A trend of increasing odds was seen with advancing maternal age. In the final model, offspring of mothers aged 35-39 years had a 1.3-fold increased odd (OR = 1,31, 95% confidence interval (95% CI:1.03-1.66)) of OCD compared with maternal aged 25-29 years. Offspring of fathers younger than 20 years had increased odds of TS/CT in the unadjusted analysis (OR = 2.43, 95% CI: 1.27-4.56).

LIMITATIONS

The study limitations included using hospital diagnoses to identify cases, with limited diagnostic validity, and the possible over representation of moderate to severe cases.

CONCLUSIONS

The lack of association between advancing paternal age and OCD is in contrast with schizophrenia, despite sharing demographic characteristics and possible shared neuropathology. Furthermore, these differences suggest different etiological pathways among TS/CT, autism spectrum disorder (ASD) and attention deficit/hyperactive disorder (ADHD), despite their frequently comorbid existence.

[Short-term clinical outcomes of neonates of secundiparous mothers: a single-center cohort study]

OBJECTIVE

To investigate the short-term clinical outcomes of neonates of secundiparous mothers, and to provide a reference for the clinical practice after the change in birth policy.

METHODS

A cohort study was performed for the parturients and their neonates born in Yongkang Maternal and Child Health Care Hospital in Zhejiang, China between June 2015 and April 2016. According to the parity of the mother, the neonates were divided into primiparous group and secundiparous group. The short-term clinical outcomes of neonates were compared between the two groups.

RESULTS

A total of 4 091 neonates who met the inclusion criteria were enrolled, and there were 2 023 neonates in the primiparous group and 2 068 in the secundiparous group. In the secundiparous group, most mothers (57.16%) were aged 26-34 years, and 16.49% were aged above 35 years. Compared with the primiparous group, the secundiparous group had a significantly higher rate of births by cesarean section (42.55% vs 25.06%; P<0.05). The percentages of neonatal respiratory distress syndrome (NRDS; 8.6% vs 3.4%) and transient tachypnea of the newborn (TTN; 7.2% vs 2.6%; P<0.05) in hospitalized neonates from the secundiparous group were significantly higher than in those from the primiparous group.

CONCLUSIONS

Elderly parturient women are not the major population of secundiparous parturients. The neonates of secundiparous mothers have a higher rate of births by cesarean section, which might be associated with increased percentages of NRDS and TTN in hospitalized neonates from the secundiparous mothers.

Paternal age and psychiatric disorders: A review

We review the hypotheses concerning the association between the paternal age at childbearing and childhood psychiatric disorders (autism spectrum- and attention deficit/hyperactive disorder) and adult disorders (schizophrenia, bipolar-, obsessive-compulsive-, and major depressive disorder) based on epidemiological studies. Several hypotheses have been proposed to explain the paternal age effect. We discuss the four main-not mutually exclusive-hypotheses. These are the de novo mutation hypothesis, the hypothesis concerning epigenetic alterations, the selection into late fatherhood hypothesis, and the environmental resource hypothesis. Advanced paternal age in relation to autism spectrum disorders and schizophrenia provided the most robust epidemiological evidence for an association, with some studies reporting a monotonic risk increase over age, and others reporting a marked increase at a given age threshold. Although there is evidence for the de novo mutation hypothesis and the selection into late fatherhood hypothesis, the mechanism(s) underlying the association between advanced paternal age and psychiatric illness in offspring remains to be further clarified. © 2016 The Authors. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics Published by Wiley Periodicals, Inc.

The Effect of Paternal Age on Oocyte Donation Outcomes

IMPORTANCE

In recent decades, a trend toward delayed childbearing is noted in developed countries. Whereas the effects of maternal age on fertility, pregnancy complications, and postnatal outcomes have been thoroughly explored, consequences of advanced paternal age are less well known. Oocyte donation cycles can be used as an optimal model to analyze the association between male ageing and reproductive outcomes with minimal confounding.

OBJECTIVE

The purpose of this work was to summarize the updated and relevant literature dealing with the effect of paternal age on oocyte donation outcomes.

RESULTS

According to the available evidence from oocyte donation cycles, it seems that no significant association exists between advanced paternal age and fertility. However, this evidence is based on few studies, many of which are of low quality, yielding conflicting results. In addition, the emerging evidence clearly indicates an increased risk of adverse postnatal manifestations of pregnancies conceived by older fathers, including de novo autosomal dominant disorders, impaired neurocognitive development, and increased risk of malignancy.

CONCLUSIONS AND RELEVANCE

This review may be of aid to medical practitioners in counseling couples on the risks of delayed childbearing.

Advancing paternal age at birth is associated with poorer social functioning earlier and later in life of schizophrenia patients in a founder population

Consistent associations have been found between advanced paternal age and an increased risk of psychiatric disorders, such as schizophrenia, in their offspring. This increase appears to be linear as paternal age increases. The present study investigates the relationship between early deviant behaviour in the first 10 years of life of patients as well as longer term functional outcome and paternal age in sporadic Afrikaner founder population cases of schizophrenia. This might improve our understanding of Paternal Age-Related Schizophrenia (PARS). Follow-up psychiatric diagnoses were confirmed by the Diagnostic Interview for Genetic Studies (DIGS). An early deviant childhood behaviour semi-structured questionnaire and the Specific Level of Functioning Assessment (SLOF) were completed. From the logistic regression models fitted, a significant negative relationship was found between paternal age at birth and social dysfunction as early deviant behaviour. Additionally, regression analysis revealed a significant negative relationship between paternal age at birth and the SLOF for interpersonal relationships later in life. Early social dysfunction may represent a phenotypic trait for PARS. Further research is required to understand the relationship between early social dysfunction and deficits in interpersonal relationships later in life.

Opposite differential risks for autism and schizophrenia based on maternal age, paternal age, and parental age differences

Background and objectives: Effects of maternal and paternal age on offspring autism and schizophrenia risks have been studied for over three decades, but inconsistent risks have often been found, precluding well-informed speculation on why these age-related risks might exist.

Methodology: To help clarify this situation we analysed a massive single population sample from Denmark including the full spectrum of autistic and schizophrenic disorders (eliminating between-study confounding), used up to 30 follow-up years, controlled for over 20 potentially confounding factors and interpret the ultimate causation of the observed risk patterns using generally accepted principles of parent-offspring conflict and life-history theory.

Results: We evaluated the effects of paternal age, maternal age and parental age difference on offspring mental disorders and found consistently similar risk patterns for related disorders and markedly different patterns between autistic and schizophrenic disorders. Older fathers and mothers both conferred increased risk for autistic but not schizophrenic disorders, but autism risk was reduced in younger parents and offspring of younger mothers had increased risk for many schizophrenic disorders. Risk for most disorders also increased when parents were more dissimilarly aged. Monotonically increasing autism risk is consistent with mutation accumulation as fathers’ age, but this explanation is invalid for schizophrenic disorders, which were not related to paternal age and were negatively correlated with maternal age.

Conclusions and implications: We propose that the observed maternally induced risk patterns ultimately reflect a shifting ancestral life-history trade-off between current and future reproduction, mediated by an initially high but subsequently decreasing tendency to constrain foetal provisioning as women proceed from first to final pregnancy.

Obsessive-Compulsive Disorder and Autism Spectrum Disorders: Longitudinal and Offspring Risk

Background

Despite substantial similarities and overlaps in the pathophysiology of obsessive-compulsive disorders (OCD) and autism spectrum disorders, little is known about the clinical and etiologic cohesion of these two disorders. We therefore aimed to determine the patterns of comorbidity, longitudinal risks, and shared familial risks between these disorders.

Methods

In a prospective study design we explored the effect of a prior diagnosis of OCD in patients and parents on the susceptibility to autism spectrum disorders and vice versa. Analyses were adjusted for sex, age, calendar year, parental age and place at residence at time of birth. As measures of relative risk incidence rate ratios (IRR) and accompanying 95% confidence intervals (CIs) were employed.

Results

The risk of a comorbid diagnosis of OCD in individuals with autism spectrum disorder and aggregation of autism spectrum disorders in offspring of parents with OCD were increased. Individuals first diagnosed with autism spectrum disorders had a 2-fold higher risk of a later diagnosis of OCD (IRR = 2.18, 95% CI = 1.91–2.48), whereas individuals diagnosed with OCD displayed a nearly 4-fold higher risk to be diagnosed with autism spectrum disorders (IRR = 3.91, 95% CI = 3.46–4.40) later in life. The observed associations were somewhat stronger for less severe types of autism spectrum disorders without a comorbid diagnosis of mental disabilities.

Conclusions

The high comorbidity, sequential risk, and shared familial risks between OCD and autism spectrum disorders are suggestive of partially shared etiological mechanisms. The results have implications for current gene-searching efforts and for clinical practice.

Effects of increased paternal age on sperm quality, reproductive outcome and associated epigenetic risks to offspring

Over the last decade, there has been a significant increase in average paternal age when the first child is conceived, either due to increased life expectancy, widespread use of contraception, late marriages and other factors. While the effect of maternal ageing on fertilization and reproduction is well known and several studies have shown that women over 35 years have a higher risk of infertility, pregnancy complications, spontaneous abortion, congenital anomalies, and perinatal complications. The effect of paternal age on semen quality and reproductive function is controversial for several reasons. First, there is no universal definition for advanced paternal ageing. Secondly, the literature is full of studies with conflicting results, especially for the most common parameters tested. Advancing paternal age also has been associated with increased risk of genetic disease. Our exhaustive literature review has demonstrated negative effects on sperm quality and testicular functions with increasing paternal age. Epigenetics changes, DNA mutations along with chromosomal aneuploidies have been associated with increasing paternal age. In addition to increased risk of male infertility, paternal age has also been demonstrated to impact reproductive and fertility outcomes including a decrease in IVF/ICSI success rate and increasing rate of preterm birth. Increasing paternal age has shown to increase the incidence of different types of disorders like autism, schizophrenia, bipolar disorders, and childhood leukemia in the progeny. It is thereby essential to educate the infertile couples on the disturbing links between increased paternal age and rising disorders in their offspring, to better counsel them during their reproductive years.

Differential Parental Influence in the Familial Aggregation of Obsessive Compulsive Disorder

The familial nature of OCD has been well established. Clinical characteristics such as early age of onset, comorbidity with tic disorders, and higher rates of symmetry symptoms have been associated with the familial aggregation of OCD, though little research has examined the differential impact of paternal and maternal OCD. The current study explored parental influence on the expression of these characteristics and reports on 310 probands diagnosed with OCD as well as 1,580 of their biological first-degree relatives. The probands were evaluated by trained clinical raters using semi-structured assessments, and relative diagnoses were obtained based on probands' reports. Similar to previous findings, 10.13% of the 1,580 relatives (n = 160) were reported to have significant OCD symptoms. Only probands who reported having a father with OCD, rather than any first-degree relative, were more likely to have an early age of onset, symmetry and exactness obsessions, and higher rates of comorbidity. No significant differences were found with respect to the probands who reported their mothers as having OCD. These findings suggest that paternal OCD, rather than simply any first-degree relative having OCD, may influence whether probands exhibit the clinical characteristics commonly associated with the familial subtype of OCD.

Family aggregation and risk factors of obsessive-compulsive disorders in a nationwide three-generation study

BACKGROUND

This nationwide register-based study investigates how often obsessive-compulsive disorders (OCD) with different age at diagnosis occur in affected families compared to control families. Furthermore, the study addresses the impact of certain risk factors, that is, sex, degree of urbanization, year of birth, and maternal and paternal age at birth.

METHODS

A total of N = 2,057 child and adolescent psychiatric subjects born between 1952 and 2000 and registered in the Danish Psychiatric Central Research Register developed OCD before the age of 18. In addition, N = 6,055 controls without any psychiatric diagnosis before age 18 and matched for age, sex, and residential region were included. Psychiatric diagnoses were also obtained for the first-degree relatives as a part of the Danish Three-Generation Study. A family load component was obtained by using various mixed regression models.

RESULTS

OCD occurred significantly more often in case than in control families. Having a mother, father, sibling, or an offspring with the disorder was proven to be a risk factor. Maternal age above 35 years, male sex by tendency, and ascending year of birth were associated with having OCD. Furthermore, case relatives did not develop OCD earlier than control relatives. The risk of OCD in the case probands was significantly increased when first-degree family members had either OCD, or tic disorders, or affective disorders, or anxiety disorders.

CONCLUSIONS

These findings based on a very large and representative dataset provide further and very solid evidence for the high family aggregation of OCD.

"Selfish spermatogonial selection": a novel mechanism for the association between advanced paternal age and neurodevelopmental disorders

There is robust evidence from epidemiological studies that the offspring of older fathers have an increased risk of neurodevelopmental disorders, such as schizophrenia and autism. The authors present a novel mechanism that may contribute to this association. Because the male germ cell undergoes many more cell divisions across the reproductive age range, copy errors taking place in the paternal germline are associated with de novo mutations in the offspring of older men. Recently it has been recognized that somatic mutations in male germ cells that modify proliferation through dysregulation of the RAS protein pathway can lead to within-testis expansion of mutant clonal lines. First identified in association with rare disorders related to paternal age (e.g., Apert syndrome, achondroplasia), this process is known as "selfish spermatogonial selection." This mechanism favors propagation of germ cells carrying pathogenic mutations, increasingly skews the mutational profile of sperm as men age, and enriches de novo mutations in the offspring of older fathers that preferentially affect specific cellular signaling pathways. This mechanism not only offers a parsimonious explanation for the association between advanced paternal age and various neurodevelopmental disorders but also provides insights into the genetic architecture (role of de novo mutations), neurobiological correlates (altered cell cycle), and some epidemiological features of these disorders. The authors outline hypotheses to test this model. Given the secular changes for delayed parenthood in most societies, this hypothesis has important public health implications.