Victimization by traditional bullying and cyberbullying and the combination of these among adolescents in 13 European and Asian countries.

There has been a lack of studies on bullying in non-western low-income and middle-income countries. This study reported the prevalence of traditional victimization, cybervictimization, and the combination of these, in 13 European and Asian countries, and explored how psychiatric symptoms were associated with victimization. The data for this cross-sectional, school-based study of 21,688 adolescents aged 13-15 were collected from 2011 to 2017. The main outcomes were traditional and cybervictimization obtained from student self-reports. The Strengths and Difficulties Questionnaire was used to assess psychiatric symptoms. Generalized estimating equation and logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs). The mean prevalence of any victimization was 28.9%, of traditional victimization only, this was 17.7%, and for cybervictimization only this was 5.1%. Cybervictimization occurred both independently, and in combination with, traditional victimization. The mean prevalence of combined victimization was 6.1%. The mean proportion of those who were cyberbullied only among those who were either cyberbullied only or bullied both traditionally and in cyber was 45.1%. The rates of prevalence varied widely between countries. In the total sample, those who experienced combined victimization, reported the highest internalizing symptoms (girls, OR 1.25, 95% CI 1.22-1.29; boys, OR 1.29, 95% CI 1.25-1.33). The study findings suggest that anti-bullying interventions should include mental health components and target both traditional and cyberbullying. Due to the overlap between these, targeting bullying should primarily focus on how to reduce bullying behavior rather than just focusing on where bullying takes place.

Post-traumatic Stress and Depressive Symptoms Among Adolescents After the 2015 Earthquake in Nepal: A Longitudinal Study.

Few longitudinal studies have focused on mental health problems among adolescents after earthquakes. We investigated changes in post-traumatic stress symptoms (PTSS) and depressive symptoms from 18 to 31 months after the 2015 earthquake in Nepal and explored potential risk factors associated with the change in psychiatric symptoms. This study comprised of 515 adolescents, aged 11-17 years from two earthquake-affected areas, one severely affected than the other. The psychiatric symptoms were assessed using the standardized Child Post-traumatic Stress Disorder Scale and the Depression Self-Rating Scale. No significant change was observed in the prevalence of PTSS and depressive symptoms from 18 to 31 months after the earthquake. Living in severely affected area and exposure to trauma after the earthquake were associated with adolescents who developed chronic or delayed PTSS and depressive symptoms. The study findings highlight the need for disaster preparedness and early interventions that strengthen support at various levels.

Incidence and comorbidities of disruptive behavior disorders diagnosed in Finnish specialist psychiatric services.

PURPOSE: Disruptive behavior disorders (DBD), including oppositional defiant disorder (ODD) and conduct disorder (CD), are some of the most common psychiatric conditions in childhood. Despite this, there has been limited research on DBDs. We examined the incidence, comorbidity and gender differences of DBDs diagnosed by specialist services. METHOD: This was a nationwide register study of 570,815 children and adolescents born in 1996-2005. The 7050 individuals diagnosed with DBD by specialist healthcare services were matched to 26,804 controls. RESULTS: By the age of 15, the cumulative incidence of diagnosed DBDs was 3.5% for boys and 1.4% for girls. The yearly incidence rate increased for girls after 13 years of age, while the incidence for boys was relatively stable between 8 and 15 years of age. When we compared subjects born between 1996-1998 and 1999-2001, we found that by the age of 12, the cumulative incidence per 100 people had increased from 0.56 to 0.68 among girls and from 2.3 to 2.6 among boys. This indicated a minor increase in treated incidence. The parents of children diagnosed with DBDs had lower educational levels than the parents of controls. Children with DBD were also more likely to have been diagnosed with other psychiatric disorders. CONCLUSION: Although DBDs were 3.5 times more common among boys during the whole follow-up period, the yearly incidence during adolescence was fairly similar between boys and girls. DBD existed alongside various psychiatric disorders at a relatively young age and only a minor increase in treated incidence was found during childhood.

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.

Relative age is associated with bullying victimisation and perpetration among children aged eight to nine.

AIM: To assess whether relative age was associated with bullying involvement and whether the associations were independent of child psychiatric symptoms. METHODS: Bullying was assessed among 8576 children in the second grade, aged 8 years, by using four cross-sectional population-based studies with identical methodology completed by children, parents and teachers in 1989 (response rate 97%), 1999 (93%), 2005 (90%) and 2013 (86%). The main outcomes were bullying victimisation and perpetration. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated with the relatively oldest as the reference group and adjusted for child psychiatric symptoms. RESULTS: The relatively youngest children, born September to December, were compared with the relatively oldest, born January to April. The youngest children had increased odds of being victims according to child (OR 1.2, 95% CI 1.1-1.4) and parent reports (OR 1.2 95% CI 1.008-1.4). The youngest also had decreased odds of being perpetrators according to child (OR 0.8, 95% CI 0.7-0.96) and teacher reports (OR 0.8, 95% CI 0.7-0.95). These findings were independent of psychiatric symptoms. CONCLUSION: The relative age effects which were found in bullying involvement were independent of psychiatric symptoms. Considering this newly recognised risk factor for victimisation is important within anti-bullying practices.

Perinatal risk factors and reactive attachment disorder: A nationwide population-based study.

AIM: To examine the association between several perinatal and obstetric risk factors and reactive attachment disorder in children diagnosed in specialised services. METHODS: In this nested case-control study, 614 cases with reactive attachment disorder and 2423 controls matched with age and sex were identified from Finnish national registers. Conditional logistic regression was used to examine the association between a number of perinatal risk factors and reactive attachment disorder. RESULTS: In the adjusted analysis, a low birthweight of <2500 g was associated with an increased odds of reactive attachment disorder, with an odds ratio (OR) of 1.96 and 95% confidence interval (CI) of 1.17, 3.30 and a birthweight of 4000-4499 grams was associated with decreased odds OR 0.49 (95% CI 0.31, 0.75). The odds for being diagnosed with reactive attachment disorder increased with a gestational age of <32 weeks OR 3.72 (95% CI 1.52, 9.10), induced labour OR 1.34 (95% CI 1.03, 1.75) and monitoring in a neonatal intensive care unit (NICU) OR 1.67 (95% CI 1.09, 2.55). CONCLUSION: We found associations between low birthweight, preterm birth, NICU admission and reactive attachment disorder. The findings add to the current literature on the understanding of the development of reactive attachment disorder in children.

Maternal serum C-reactive protein (CRP) and offspring attention deficit hyperactivity disorder (ADHD).

Exposure to infection and inflammation during the fetal period are associated with offspring neuropsychiatric disorders. Few previous studies have examined this association with ADHD with mixed findings. This study aims to examine the association between early gestational maternal C-reactive protein (CRP), prospectively assayed in stored maternal sera and the risk of ADHD in offspring. This study is based on the Finnish Prenatal studies of ADHD (FIPS-ADHD) with a nested case-control design. It includes all singleton-born children in Finland between January 1, 1998 and December 31, 1999 and diagnosed with ADHD. A total of 1079 cases and equal number of controls were matched on date of birth, sex and place of birth. Maternal CRP levels were assessed using a latex immunoassay from archived maternal serum specimens, collected during the first and early second trimester of pregnancy. Elevated maternal CRP when analyzed as a continuous variable was not associated with offspring ADHD (OR 1.05, 95% CI 0.96-1.15). No significant associations were seen in the highest quintile of CRP (OR 1.18, 95% CI 0.88-1.58). The results were similar in both sexes as well as among ADHD cases with or without comorbid ASD or conduct disorder. In this first study examining CRP, a biomarker for inflammation, during early pregnancy in relation to offspring ADHD, we report no significant associations. The lack of any association, when considered with positive findings seen in ASD and schizophrenia, and negative findings in bipolar disorder suggests different pathways linking maternal immune activation and development of various neuropsychiatric disorders.

Associations between Chinese adolescents subjected to traditional and cyber bullying and suicidal ideation, self-harm and suicide attempts.

BACKGROUND: The incidence of bullying is high among adolescents. Adolescents who were victims of bullying have a higher risk of self-harm and suicidal behavior than adolescents who were non-victims. However, research on suicide and both traditional and cyber bullying was limited in China. Therefore, this study examined the associations between Chinese adolescents who were the victims of traditional and cyber bullying and the prevalence of suicidal ideation, self-harm and suicide attempts. METHODS: This was a population-based study of 2647 students (51.2% girls) with a mean age of 13.6 ± 1.1 years from 10 junior high schools in Shantou, China. Information on bullying victimization, suicidal ideation, self-harm and suicide attempts were collected using a self-administered questionnaire and the psychopathology of the students was assessed using the Strengths and Difficulties Questionnaire (SDQ). The associations were examined with multinomial logistic regression, adjusted for covariates. RESULTS: Traditional bullying victimization was reported by 16.7% of the adolescents, cyber bullying victimization by 9.0% and both by 3.5%. The prevalence of suicidal ideation was 23.5%, self-harm was 6.2% and suicide attempts was 4.2%. Psychopathology symptoms were risk factors for suicide ideation only, ideation plus self-harm, self-harm only and suicide attempts. Victims of both traditional and cyber bullying had the highest risk of suicidal ideation only, ideation plus self-harm and suicide attempts, compared to those reporting one form of bullying. Victims of cyber bullying only had the second highest risk of suicidal ideation only and suicidal ideation plus self-harm compared to non-victims. CONCLUSIONS: Adolescents who were victims of both traditional and cyber bullying had greater risks of adverse outcomes of suicidal ideation only, suicidal ideation plus self-harm and suicide attempts. The results of the current study suggest that those exposed to both forms of bullying should be routinely screened for suicidal risk. In addition, school-based anti-bully interventions should also target cyber bullying.

Risk factors for impaired maternal bonding when infants are 3 months old: a longitudinal population based study from Japan.

BACKGROUND: Impaired maternal bonding has been associated with antenatal and postnatal factors, especially postpartum depression. Only a few population-based, longitudinal studies have examined the association between maternal depression and bonding in outside western countries. In addition, little is known about the association between psychosocial factors during pregnancy and impaired maternal bonding. The aim of this study was to investigate risk factors associated with impaired maternal bonding 3 months after delivery using Japanese population-based, longitudinal study from pregnancy period to 3 months after delivery. METHODS: This study was performed at the public health care center in Hekinan city, Aichi prefecture, Japan. Mothers who participated the infant's health check-up 3 months after delivery from July 2013 to Jun 2015 completed the Postpartum Bonding Questionnaire (PBQ) and the Edinburgh Postnatal Depression Scale (EPDS) 1 month after delivery. Information was also provided from home visit at 1 month after delivery, birth registration form, and pregnancy notification form. The study included 1060 mothers with a mean age of 29.90 years, who had given birth at a mean of 38.95 weeks. RESULTS: Bivariate and multivariate logistic regression analyses were conducted to identify the association between antenatal and postnatal factors and impaired maternal bonding. The main findings were that maternal negative feelings about pregnancy (OR = 2.16, 95% CI = 1.02-4.56) and postpartum depression at 1 month after delivery (OR = 7.85, 95% CI = 3.44-17.90) were associated with higher levels of impaired maternal bonding 1 months after delivery. Mothers who had delivered their first child had increased odds of a moderate level of impaired maternal bonding 3 months after delivery (OR = 1.85, 95% CI = 1.22-2.81). CONCLUSIONS: The findings emphasize the importance of identifying mothers with depression and those with maternal negative feelings towards pregnancy to assess possible impaired maternal bonding.

Time trends in the incidence of diagnosed depression among people aged 5-25 years living in Finland 1995-2012.

Background: Knowledge of time trends for depression is important for disease prevention and healthcare planning. Only a few studies have addressed these questions regarding the incidence and cumulative incidence of diagnosed depression from childhood to early adulthood and findings have been inconclusive. Aim: The aim of this national register-based Finnish study was to report the time trends of the age-specific and gender-specific incidence and cumulative incidence of diagnosed depression. Methods: The study sample included all 1,245,502 singletons born in Finland between 1 January 1987 and 31 December 2007 and still living in Finland at the end of 2012. The participants were divided into three cohorts by birth year: 1987-1993, 1994-2000 and 2001-2007. Depression diagnoses (ICD-9: 2961; ICD-10: F32, F33) given in 1995-2012 were available and identified from the Care Register for Health Care. Results: Ten percent of the females and five percent of the males were diagnosed with depression in specialized services by age 25 years. The cumulative incidence of depression by age 15 years rose from 1.8% (95% CI 1.8-1.9) to 2.9% (95% CI 2.8-3.0) in females and from 1.0% (95% CI 1.1-1.2) to 1.6% (95% CI 1.6-1.7) in males when the cohorts born 1987-1993 and 1994-2000 were compared. Conclusions: A larger proportion of young people in Finland are diagnosed with depression in specialized services than before. This can be due to better identification, more positive attitudes to mental health problems and increased availability of the services.

Parental Risk Factors among Children with Reactive Attachment Disorder Referred to Specialized Services: A Nationwide Population-Based Study.

This nationwide population-based register study examined the family and parental risk factors associated with offspring reactive attachment disorder (RAD). We identified 614 children diagnosed with RAD from the Finnish Care Register for Health Care and each case was matched with four controls. Univariate and multivariate models examined the associations between risk factors and RAD. In the multivariate model, offspring RAD was associated with only mother, only father and both parents having psychiatric diagnoses. Increased odds were observed for maternal smoking during pregnancy, single motherhood and paternal age ≥ 45 years. This study provides information on several parental adversities and offspring RAD that have important implications for public health, when planning early prevention and interventions in infant mental health.

Social risk factors for speech, scholastic and coordination disorders: a nationwide register-based study.

BACKGROUND: Broadly defined learning and coordination disorders (LCDs) are common in the population and have previously been associated with familial social risk factors and male sex. However, comprehensive nationwide studies of these risk factors in LCD subgroups are lacking. Our objective was to assess different LCDs in relation to sex and maternal education, marital status and socioeconomic status based on occupation. METHODS: We conducted a nationwide register-based study. The following diagnoses were identified from the Finnish Hospital Discharge Register (FHDR) according to the ICD-10 (n = 28,192): speech disorders (F80), scholastic disorders (F81), motor and coordination disorders (F82) and mixed developmental disorder (F83). To study cumulative incidence and male: female ratios of service use of LCDs, we used a cohort design among all Finnish children born singleton 1996-2007 (n = 690,654); to study social risk factors, we used a nested case-control design with extensive register data on both cases and matched controls (n = 106,616). RESULTS: The cumulative incidence was 4.7% for any LCD by age 15 and the changes in cumulative incidence over time were minor. The male: female ratios were 2.2-3.0 across LCD subgroups. Learning and coordination disorders were more common in households with lower maternal education, socioeconomic status based on occupation and among children with single mothers at the time of birth; the odds ratios (OR) for any LCD were 1.2-1.9 across risk factors. The odds for LCD diagnosis increased linearly with the number of social risk factors, except for coordination disorder. The effect size of three risk factors was highest in the group with mixed or multiple LCDs; OR 3.76 (95% CI 3.31-4.28). CONCLUSIONS: Multiple social risk factors increase the odds for multiple, more comprehensive learning difficulties. The findings have implications for service planning, as early identification and interventions of learning and coordination disorders might reduce related long-term social adversities.

Lower Apgar scores and Caesarean sections are related to attention-deficit/hyperactivity disorder.

AIM: We examined the associations between prenatal, birth-related and newborn risk factors and attention-deficit/hyperactivity disorder (ADHD). METHODS: In this population-based study, 10 409 subjects diagnosed with ADHD by 31 December 2011 and 39 124 controls, born between 1 January 1991 and 31 December 2005, were identified from Finnish nationwide registers. Perinatal data were obtained from the Birth Register. Conditional logistic regression was used to examine the associations after controlling for confounders. RESULTS: Lower Apgar scores were associated with a higher risk of ADHD, with odds ratios of 1.12 (95% confidence intervals 1.06-1.19) for one-minute Apgar scores of 7-8, 1.17 (95% CI 1.02-1.35) for scores of 5-6 and 1.41 (95% CI 1.18-1.68) for scores of 0-4, compared to Apgar scores of 9-10. Elective Caesarean sections were associated with an increased risk of ADHD with an adjusted odds ratio of 1.15 (95% CI 1.05-1.26). Other identified risk factors were breech presentation, induced labour and admission to a neonatal intensive care unit. Low umbilical artery pH did not increase the risk of ADHD. CONCLUSION: Elective Caesareans and perinatal adversities leading to lower Apgar scores increased the risk of ADHD. Future research to identify the mechanisms behind these findings is warranted.

Register-based study of the incidence, comorbidities and demographics of obsessive-compulsive disorder in specialist healthcare.

BACKGROUND: Incidence of obsessive-compulsive disorder (OCD) has been suspected to increase but nationwide epidemiological studies are limited. This study aims to examine sex-specific incidence time trends and characterize psychiatric and neurodevelopmental comorbidities and sociodemographic risk factors of OCD in specialist healthcare in Finland. METHODS: A nationwide register-based study using data from four Finnish registers identified 3372 OCD cases and 13,372 matched controls (1:4). Cumulative incidence in subjects born between 1987 and 2001 was estimated at ages of 10, 15, 20 and 23 years. Conditional logistic regression was used to examine the sociodemographic factors. RESULTS: The cumulative incidence of OCD was 0.4% by age 23. Incidence by age 15 among three cohorts increased from 12.4 to 23.7 /10000 live born males and 8.5 to 28.0 /10000 live born females. 73% of the sample had a comorbid condition. Males were significantly more comorbid with psychotic and developmental disorders; females were more comorbid with depressive and anxiety disorders (p <0.001). Higher maternal SES was associated with an increased risk of OCD (OR 1.4; 95% CI 1.1-1.6). CONCLUSIONS: These findings suggest that incidence of treated OCD in specialist healthcare has increased. The reason may be increased awareness and rate of referrals but a true increase cannot be ruled out. Further research on risk factors of OCD is warranted.

Obstetric and Neonatal Adversities, Parity, and Tourette Syndrome: A Nationwide Registry.

OBJECTIVE: To determine the relationships between parity, obstetric adversities, neonatal factors, and Tourette syndrome in a large nationwide cohort. STUDY DESIGN: This nationwide, register-based, nested case-control study identified all children diagnosed with Tourette syndrome born between 1991 and 2010 from the Finnish Hospital Discharge Register (n = 767). Each case was matched to 4 controls. Information on parity, obstetric, and neonatal factors was obtained from the Finnish Medical Birth Register. Conditional logistic regression was used to determine the relationship between parity, obstetric, and neonatal factors, and Tourette syndrome. RESULTS: Nulliparity was associated with increased odds for Tourette syndrome (OR 1.7, 95% CI 1.4-2.2), and 3 or more previous births was associated with decreased odds for Tourette syndrome (OR 0.5, 95% CI 0.3-0.9) compared with parity 1-2. Birth weight 4000-4499 g was associated with decreased odds for Tourette syndrome (OR 0.7, 95% CI 0.5-0.9). Low birth weight, gestational age, weight for gestational age, Apgar score at 1 minute, induced labor, birth type or presentation, neonatal treatment, or maternal blood pressure were not associated with Tourette syndrome. CONCLUSIONS: Increasing parity and high birth weight are associated with decreased odds for Tourette syndrome.

Association between immigrant background and ADHD: a nationwide population-based case-control study.

BACKGROUND: Information about psychiatric disorders among those with immigrant parents is important for early detection and service development. The aim of this study is to examine the association between parental immigration and the diagnosis of attention-deficit hyperactivity disorder (ADHD) in offspring in Finland. METHODS: This matched case-control study was based on a national birth cohort. The sample included all singletons who were born in Finland in 1991-2005 and diagnosed with ADHD by the year 2011 (n = 10,409) and their matched controls (n = 39,124). Nationwide registers were used to identify participants and to gather information on the parents' country of birth and native language. Conditional logistic regression analyses were conducted using maternal and paternal migration status and region of birth as well as time since maternal migration as exposure factors. RESULTS: The likelihood of being diagnosed with ADHD was significantly increased among children of two immigrant parents [adjusted odds ratio (aOR) 4.7, 95% CI 3.4-6.6] and children of an immigrant father (aOR 1.9, 95% CI 1.6-2.2). The likelihood of receiving an ADHD diagnosis was equal among children whose mother was a recent immigrant when she gave birth and those whose mother had stayed in Finland at least for a year before birth. The association between parental migration and ADHD diagnosis was strongest among fathers born in sub-Saharan Africa or Latin America and among mothers born in sub-Saharan Africa or North Africa and Middle East. Children, whose parents were born in countries with low Human Development Index (HDI), were more often diagnosed with ADHD. CONCLUSIONS: The increased likelihood of ADHD diagnosis among children of immigrants indicates increased exposure to environmental risk factors, differences in the use of health services, or challenges in diagnosing immigrants' children.

Prenatal smoking exposure and neuropsychiatric comorbidity of ADHD: a finnish nationwide population-based cohort study.

BACKGROUND: Prenatal smoking exposure has been associated with attention-deficit/hyperactivity disorder (ADHD). ADHD is commonly associated with a wide spectrum of psychiatric comorbidity. The association between smoking and neuropsychiatric comorbidity of ADHD has remained understudied. The aim of this study is to examine the association between prenatal exposure to maternal smoking and offspring ADHD, and test whether the smoking-ADHD associations are stronger when ADHD is accompanied by other lifetime neuropsychiatric comorbidities. METHODS: The study is based on a nested case-control design and includes all Finnish singletons born between 1991 and 2005 and diagnosed with ADHD by 2011 (n = 10,132), matched with four controls (n = 38,811) on date of birth, sex and residence in Finland. RESULTS: The risk for ADHD with or without comorbidity was significantly increased among offspring exposed to maternal smoking on adjusting for potential confounders (OR = 1.75, CI 95 % = 1.65-1.86). Compared to the only ADHD cases, subjects with comorbid conduct disorder or oppositional defiant disorder had a significantly stronger association with smoking exposure (OR = 1.80, CI 95 % = 1.55-2.11). CONCLUSIONS: Prenatal smoking represents an important risk factor for the ADHD comorbid with CD/ODD. Further research on the association between prenatal smoking exposure and neuropsychiatric comorbidity of ADHD is needed considering the increased risk among these subjects of an overall poor health outcome as compared to only ADHD. In particular, studies utilizing biomarkers or including subjects with neuropsychiatric conditions with and without comorbid ADHD are needed.

Demographic Characteristics and Psychiatric Comorbidity of Children and Adolescents Diagnosed with ADHD in Specialized Healthcare.

Recent studies have shown an increasing incidence of attention-deficit/hyperactivity disorder (ADHD) among children diagnosed in specialized services. This study aims to describe children with ADHD in Finnish specialized healthcare by reporting the demographic characteristics, time trends in diagnosis, psychiatric comorbidity, and the validity of register-based diagnoses. All the singletons born in Finland between 1991 and 2005 and diagnosed with ADHD by 2011 were identified and their psychiatric comorbidity data was obtained from the Finnish Hospital Discharge Register (FHDR). Parents of 69 patients were interviewed via telephone for a diagnostic validation. A total of 10,409 children were identified with ADHD, with a male: female ratio of 5.3:1 and a psychiatric comorbidity rate of 76.7 %. Of the validation sample 88 % met the diagnostic criteria of ADHD for DSM-IV. There is an increasing trend of ADHD diagnosis among both males and females. Psychiatric comorbidity is common and includes a wide range of disorders among children with ADHD. There was an increase of ADHD diagnoses especially among boys. More attention is needed to detect ADHD among girls in health services. Diagnoses in the FHDR show diagnostic validity and their sociodemographic patterns are in line with previous studies.

Prenatal Maternal Smoking and Tourette Syndrome: A Nationwide Register Study.

This is the first nationwide register-based study to examine the relationship between prenatal maternal smoking and Tourette syndrome. A total of 767 children diagnosed with Tourette syndrome were identified from the Finnish Hospital Discharge Register. Each case was matched to four controls. Information on maternal smoking during pregnancy was obtained from the Finnish Medical Birth Register. Conditional logistic regression models were used for statistical analyses. Prenatal maternal smoking was associated with Tourette syndrome when comorbid with ADHD (OR 4.0, 95 % CI 1.2-13.5, p = 0.027 for exposure during first trimester, OR 1.7, 95 % CI, 1.05-2.7, p = 0.031 for exposure for the whole pregnancy). There was no association between maternal smoking during pregnancy and Tourette syndrome without comorbid ADHD (OR 0.5, 95 % CI 0.2-1.3, p = 0.166, OR 0.9, 95 % CI 0.7-1.3, p = 0.567). Further research is needed to elucidate the mechanisms behind the association between prenatal maternal smoking and Tourette syndrome with comorbid ADHD.

Parental age and the risk of bipolar disorders.

OBJECTIVES: Studies on the association between parental age and bipolar disorder (BPD) are scarce and with inconsistent findings. The aim of this study was to examine the association of parental age and age difference between parents with risk of BPD in offspring. METHODS: This nested case-control study identified 1,861 cases of individuals with BPD born in Finland during 1983-1998 and diagnosed by the end of 2008, and 3,643 sex- and date of birth-matched controls from nationwide population-based registers. Conditional logistic regression was used to examine the association adjusting for potential confounding due to age of the other parent, parental psychiatric history, educational level, and place of birth. RESULTS: A U-shaped association of unadjusted odds ratios (ORs) for BPD risk was seen in different paternal age categories, with the odds increasing at both ends of the age spectrum. In the adjusted analyses, offspring of fathers aged ≥ 50 years had a 2.8-fold increased odds [OR = 2.84, 95% confidence interval (CI): 1.32-6.12] of BPD as compared to those with fathers aged 30-34 years. The odds were increased 1.3-fold (OR = 1.35, CI: 1.06-1.72) in fathers aged 20-24 years. No significant association was found between maternal age and BPD in the adjusted analyses. Age difference between parents was not associated with BPD. CONCLUSIONS: The increased risk of BPD in offspring of the youngest and oldest fathers in the study suggests the involvement of different biological and psychosocial factors at the two ends of the paternal age spectrum. These findings may be significant in the context of advancing parental age in recent times.