Family load estimates of schizophrenia and associated risk factors in a nation-wide population study of former child and adolescent patients up to forty years of age

The impact of parental psychopathology and sociodemographic factors in selective mutism - a nationwide population-based study

BACKGROUND

Selective mutism (SM) is nowadays considered a relatively rare anxiety disorder characterized by children failing to speak in certain situations. Research on risk factors for SM are limited in comparison to other psychiatric disorders. The aim of this study was to examine several potential risk factors for SM in a large nationwide cohort, namely parental psychopathology, parental age, maternal SES, urbanicity, maternal marital status and parental immigration status.

METHODS

This nested case-control study comprised 860 cases with SM, identified from the Finnish Hospital Discharge Register and 3250 controls matched for sex and age from the Finnish Central Population Register. Conditional logistic regression was used to examine the association between the risk factors and SM.

RESULTS

If both parents had any psychiatric disorder, this almost tripled their odds of having a child with SM (OR 2.8, 95% CI 2.0-4.0). There were increased rates of all types of psychiatric disorders in the parents of the children with SM, with a wider range of diagnoses among the mothers than fathers. Fathers over 35 years (OR 1.4, 95% CI 1.1-1.8) were significantly more likely to have children with SM. Offspring of a single mother had a 2-fold (OR = 2.0, 95% CI 1.4-3.0) increased odds of SM than mothers who were married or in a relationship.

CONCLUSIONS

Several parental psychiatric disorders were associated with offspring SM. This points towards a shared aetiology of psychiatric disorders. Findings on paternal age and single motherhood help to improve our understanding of risk factors for SM.

Risk of schizophrenia in relatives of individuals affected by schizophrenia: A meta-analysis

A meta-analysis was conducted to estimate schizophrenia incidence in first-degree relatives (FDRs) of probands diagnosed with schizophrenia. The aim was to inform future schizophrenia research and improve accuracy of risk communication to patients. Schizophrenia risk in FDRs with 1 or 2 probands with schizophrenia was investigated by conducting a systematic review of cohort and case-control studies with the following criteria: published between 1977 and 2018; reported odds ratios (OR), relative risk (RR) or sufficient raw data to calculate OR or RR; used appropriate diagnostic criteria; and reported systematic proband recruitment and ascertainment of relatives. Studies were obtained via EMBASE and MEDLINE electronic database searches. From an initial 5755 articles, 19 met the inclusion criteria. Mean effect sizes across studies were estimated using random effects methods. Estimates for schizophrenia risk were OR = 7.69 (95% CI 5.11-11.56) for FDRs of one proband with schizophrenia compared to healthy control probands, increasing to OR = 11.11 (95% CI = 1.45-85.02) for FDRs with two probands with schizophrenia. These findings support the existing literature suggesting significant genetic liability for schizophrenia. The results can be used to educate individuals with a family history of schizophrenia about their risk.

Psychomotor agitation in subjects hospitalized for an acute exacerbation of Schizophrenia

The aims of this study were to establish the prevalence of moderate and severe psychomotor agitation in patients hospitalized for an active phase of schizophrenia, the associations between psychomotor agitation and patients' demographic and clinical variables, the intra-individual stability of the agitated/non-agitated dichotomy in independent psychotic breakdowns. The study was performed on a database relative to 630 inpatients hospitalized with a diagnosis of schizophrenia. Psychomotor agitation was measured with the Positive and Negative Syndrome Scale - Excited Component (PANSS-EC). Prevalence of moderate and severe psychomotor agitation was 40.5% and 23.7%, respectively. Non-agitated patients were older, with longer illness history and duration of untreated psychosis, were more frequently on antipsychotic medication, had lower incidence of recent use of substances, and functioned better before the index hospitalization than moderately and/or severely agitated patients. Non-agitated patients had lower scores for total PANSS and Emsley's positive and anxiety dimensions. Compared with the severely agitated group, non-agitated and moderately agitated patients scored more in Emsley's depression dimension. Poor functioning before index hospital admission, higher scores for negative subscale and Emsley's positive dimension and use of substances exerted an effect on risk of psychomotor agitation.

Family aggregation and risk factors in substance use disorders over three generations in a nation-wide study

Objective

This nation-wide register-based study investigated how often substance use disorders (SUD) and co-morbid disorders occurred in affected families compared to control families.

Method

A total of N = 2504 child and adolescent psychiatric participants who were born between 1969 and 1986 and were registered in the Danish Psychiatric Central Research Register (DPCRR) had a mental disorder before the age of 18 and developed SUD at some point during their life-time. In addition, N = 7472 controls without any psychiatric diagnosis before age 18 and matched for age, sex, and residential region were included. Psychiatric diagnoses of the first-degree relatives were also obtained. A family load component was assessed.

Results

SUD occurred significantly more often in case families than in control families. SUD risk factors included SUD, depression, anxiety disorders, personality disorders, or conduct disorders in the family. Furthermore, male sex, more recent year of birth, and living in the capital city of Copenhagen were also significantly associated with having SUD. The family load explained 30% of the SUD manifestation in the case-probands. The findings in the total SUD group were mostly replicated in the two major subgroups of pure alcohol or multiple substance use disorders.

Discussion

These findings based on a very large and representative dataset provide additional evidence for the strong family aggregation and further risk factors in SUD. The pattern of risk factors is largely the same for the total group of SUD and the major subgroups of pure alcohol and multiple substance use disorders.

Oxidative Stress and DNA Damage in Untreated First-Episode Psychosis in Adolescents

OBJECTIVE

Oxidative stress has been reported to play a role in the psychopathology of schizophrenia, though only a few studies have investigated the relationship between early-onset schizophrenia and oxidative stress. The aim of the present study is to evaluate the level of oxidative stress and the presence of DNA damage in first-episode psychosis (FEP) in adolescents.

METHODS

This study was conducted in the Department of Child Psychiatry of the Dicle University Hospital. It included 20 adolescent patients (age 11-17 years) with psychosis (acute psychosis, schizophreniform disorder, or schizophrenia) according to DSM-IV criteria who had received no previous psychiatric therapy (patient group) and 20 age/gender-matched healthy adolescents (control group). Structured psychiatric interviews [Kiddie Schedule for Affective Disorders and Schizophrenia, Present and Lifetime Version (K-SADS-PL) and Positive and Negative Symptom Scale (PANSS)] were conducted on the patients, and the Clinical Global Impressions (CGI) scale was used to evaluate the severity of disease. Glutathione peroxidase (GPx), superoxide dismutase (SOD), coenzyme Q (CoQ), and 8-hydroxy-2-deoxyguanosine (8-OHdG) levels were determined using the ELISA method and commercial ELISA kits.

RESULTS

The mean age was 14.5 ± 1.6 years in the FEP group (male-to-female ratio: 8/12) and 14.4 ± 1.5 years in the control group (male-to-female ratio: 8/12). There were no differences between the patient and control groups in terms of SOD, GPx, or 8-OHdG values (p > 0.05).

CONCLUSIONS

This study on DNA damage and oxidative stress in FEP in adolescents had a small sample size, and our data suggest that oxidative stress is associated with a chronic disease course rather than being an early sign of early-onset schizophrenia.

Family Aggregation and Risk Factors in Phobic Disorders over Three-Generations in a Nation-Wide Study

Objective

This nation-wide register-based study investigated how often phobic disorders (PHO) and co-morbid disorders occur in affected families compared to control families. Furthermore, the study addressed the impact of sex, year of birth, and degree of urbanization in terms of risk factors.

Method

A total of N = 746 child and adolescent psychiatric participants born between 1969 and 1986 and registered in the Danish Psychiatric Central Research Register (DPCRR) with a diagnosis of a mental disorder before the age of 18, and developed PHO at some point during their life-time until a maximum age of 40 years were included. In addition, N = 2229 controls without any diagnosis of mental disorders before age 18 and that were matched for age, sex, and residential region were included. Diagnoses of mental disorders were also obtained from the first- degree relatives as a part of the Danish Three Generation Study (3GS). A family load component was obtained by using various mixed regression models.

Results

PHO occurred significantly more often in case than in control families, in particular, in mothers and siblings. Substance use disorders (SUD), Depressive disorders (DEP), anxiety disorders (ANX) and personality disorders (PERS) in the family were significantly associated with specific phobia in the case-probands. After controlling for various mental disorders comorbid to PHO it was found that some of the family transmission could be caused by various other mental disorders in family members rather than the PHO itself. Female sex and more recent year of birth were further risk factors while region of residence was not related to the manifestation of PHO. Case-relatives did not develop PHO earlier than control relatives. After adjusting for various additional explanatory variables, the family load explained only 0.0013% of the variance in the manifestation of PHO in the case-probands

Discussion

These findings, based on a very large and representative dataset, provide evidence for the family aggregation and further risk factors in PHO. In contrast to anxiety disorders and other major mental disorders the family load of PHO in this nation-wide study was rather low.

The relationship between facial emotion recognition and executive functions in first-episode patients with schizophrenia and their siblings

BACKGROUND

Although many studies have examined executive functions and facial emotion recognition in people with schizophrenia, few of them focused on the correlation between them. Furthermore, their relationship in the siblings of patients also remains unclear. The aim of the present study is to examine the correlation between executive functions and facial emotion recognition in patients with first-episode schizophrenia and their siblings.

METHODS

Thirty patients with first-episode schizophrenia, their twenty-six siblings, and thirty healthy controls were enrolled. They completed facial emotion recognition tasks using the Ekman Standard Faces Database, and executive functioning was measured by Wisconsin Card Sorting Test (WCST). Hierarchical regression analysis was applied to assess the correlation between executive functions and facial emotion recognition.

RESULTS

Our study found that in siblings, the accuracy in recognizing low degree 'disgust' emotion was negatively correlated with the total correct rate in WCST (r = -0.614, p = 0.023), but was positively correlated with the total error in WCST (r = 0.623, p = 0.020); the accuracy in recognizing 'neutral' emotion was positively correlated with the total error rate in WCST (r = 0.683, p = 0.014) while negatively correlated with the total correct rate in WCST (r = -0.677, p = 0.017). People with schizophrenia showed an impairment in facial emotion recognition when identifying moderate 'happy' facial emotion, the accuracy of which was significantly correlated with the number of completed categories of WCST (R(2) = 0.432, P < .05). There were no correlations between executive functions and facial emotion recognition in the healthy control group.

CONCLUSIONS

Our study demonstrated that facial emotion recognition impairment correlated with executive function impairment in people with schizophrenia and their unaffected siblings but not in healthy controls.

A nation-wide study of the family aggregation and risk factors in anorexia nervosa over three generations

OBJECTIVE

This nation-wide register-based study investigated how often anorexia nervosa (AN) and co-morbid disorders occur in affected families compared with control families. Furthermore, the study addressed the impact of sex, year of birth, and degree of urbanization in terms of risk factors.

METHOD

A total of N = 2,370 child and adolescent psychiatric subjects born between 1951 and 1996 and registered in the Danish Psychiatric Central Research Register (DPCRR) had any mental disorder before the age of 18 and developed AN at some point during their life-time. In addition, N = 7,035 controls without any psychiatric diagnosis before age 18 and matched for age, sex, and residential region were included. Psychiatric diagnoses were also obtained on the first-degree relatives as a part of the Danish Three Generation Study (3GS). A family load component was obtained by using various mixed regression models.

RESULTS

AN occurred significantly more often in case than in control families. AN Risk factors included having a sibling with AN, affective disorders in family members, and co-morbid affective, anxiety, obsessive-compulsive, personality, or substance use disorders. Furthermore, female sex, and ascending year of birth were significantly associated with having AN. Urbanization was not related to the family load of AN and case-relatives did not develop AN earlier than control relatives.

DISCUSSION

These findings based on a very large and representative dataset provide evidence for the family aggregation and further risk factors in AN.

Reduced brain reward response during cooperation in first-degree relatives of patients with psychosis: an fMRI study

BACKGROUND

Psychosis is characterized by a profound lack of trust and disturbed social interactions. Investigating the neural basis of these deficits is difficult because of medication effects but first-degree relatives show qualitatively similar abnormalities to patients with psychosis on various tasks. This study aimed to investigate neural activation in siblings of patients in response to an interactive task. We hypothesized that, compared to controls, siblings would show (i) less basic trust at the beginning of the task and (ii) reduced activation of the brain reward and mentalizing systems.

METHOD

Functional magnetic resonance imaging (fMRI) data were acquired on 50 healthy siblings of patients with psychosis and 33 healthy controls during a multi-round trust game with a cooperative counterpart. An a priori region-of-interest (ROI) analysis of the caudate, temporoparietal junction (TPJ), superior temporal sulcus (STS), insula and medial prefrontal cortex (mPFC) was performed focusing on the investment and repayment phases. An exploratory whole-brain analysis was run to test for group-wise differences outside these ROIs.

RESULTS

The siblings' behaviour during the trust game did not differ significantly from that of the controls. At the neural level, siblings showed reduced activation of the right caudate during investments, and the left insula during repayments. In addition, the whole-brain analysis revealed reduced putamen activation in siblings during investments.

CONCLUSIONS

The findings suggest that siblings show aberrant functioning of regions traditionally involved in reward processing in response to cooperation, which may be associated with the social reward deficits observed in psychosis.

Family load estimates and risk factors of anxiety disorders in a nationwide three generation study

The present study investigated how often anxiety disorders with different ages of onset occurred in affected families compared to control families. Furthermore, the study addressed the impact of sex, region of residence, year and month of birth, and parental age at birth. The sample included N=1373 child and adolescent psychiatric participants born between 1952 and 2000 and registered in the Danish Psychiatric Central Register (DPCR) who developed an anxiety disorder before the age of 18. N =4019 controls without any psychiatric diagnosis before age 18, were matched for age, sex, and residential region. Psychiatric diagnoses were also obtained for parents, siblings, and offspring. A family load component was obtained by using various mixed regression models. Anxiety disorders occurred significantly more often in case than in control families. Having a mother, father, or a sibling with the disorder was proven to be a risk factor. Female sex, year of birth, and region of residence were also associated with having an anxiety disorder. Furthermore, case relatives did not develop an anxiety disorder earlier than control relatives. These findings, based on a very large and representative dataset, provide further and solid evidence for the family aggregation of anxiety disorders.

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.

A three generations nation-wide population study of family load estimates in bipolar disorder with different age at onset

OBJECTIVES

This nation-wide register-based study investigates how often bipolar disorder (BD) occurs in affected families compared to control families by estimating the family load as a random effect; this effect measures the degree of dependence among family members in relation to BD. Furthermore, the study addresses the impact of certain risk factors, namely, sex, age at onset of BD, degree of urbanization, year of birth, month of birth, and maternal and paternal age at birth.

METHOD

A total of N=1204 children and adolescent psychiatric cases born between 1950 and 1997 and registered in the Danish Central Psychiatric Register (DPCR) developed BD before the age of 58 years. N=3553 controls without any psychiatric diagnosis were matched for age, gender, and region of residence. Psychiatric diagnoses were also obtained on the relatives, e.g. parents, siblings, and offspring as a part of the Danish Three Generation Study (3GS). A family component was obtained by using different regression models.

RESULTS

Familial factors accounted for 20% of the variation in disease outcome when controlling for year and month of birth, sex, and degree of urbanization. Only female sex was associated with an increased hazard ratio of BD. Also having a mother, father or a sibling with the disorder was proven to be a significant risk factor. Furthermore, case relatives did not develop BD earlier than control relatives.

CONCLUSION

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