Prenatal and perinatal risk factors for bipolar disorder

Bipolar disorder (BPD) is a severe mental disorder associated with considerable morbidity and mortality. Prenatal insults have been shown to be associated with later development of mental disorders and there is a growing interest in the potential role of prenatal and perinatal risk factors in the development of BPD. The aims of this thesis were to describe the overall study design of the Finnish Prenatal Study of Bipolar Disorders (FIPS-B) and demographic characteristics of the sample. Furthermore, it was aimed to examine the association of parental age, parental age difference, perinatal complications and maternal smoking during pregnancy with BPD. This thesis is based on FIPS-B, a nested case-control study using several nationwide registers. The cases included all people born in Finland between January 1st 1983 and December 31st 1998 and diagnosed with BPD according to the Finnish Hospital Discharge Register (FHDR) before December 31st 2008. Controls for this study were people who were without BPD, schizophrenia or diagnoses related to these disorders, identified from the Population Register Centre (PRC), and matched two-fold to the cases on sex, date of birth (+/- 30 days), and residence in Finland on the first day of diagnosis of the matched case. Conditional logistic regression models were used to examine the association between risk factors and BPD. This study included 1887 BPD cases and 3774 matched controls. The mean age at diagnosis was 19.3 years and females accounted for 68% of the cases. Mothers with the lowest educational level had the highest odds of having BPD in offspring. Being born in Eastern and Southern region of Finland increased the odds of having BPD later in life. A U-shaped distribution of odds ratio was observed between paternal age and BPD in the unadjusted analysis. Maternal age and parental age difference was not associated with BPD. Birth by planned caesarean section was associated with increased odd of BPD. Smoking during pregnancy was not associated with BPD in the adjusted analyses. Region of birth and maternal educational level were associated with BPD. Both young and old father’s age was associated with BPD. Most perinatal complications and maternal smoking during pregnancy were not associated with BPD. The findings of this thesis, considered together with previous literature, suggest that the pre- and perinatal risk factor profile varies among different psychiatric disorders.Kaksisuuntaisen mielialahäiriön pre- ja perinataaliset riskitekijät Kaksisuuntainen mielialahäiriö on vakava mielenterveyden häiriö, johon liittyy merkittävä sairastuvuus ja kuolleisuus. Syntymää edeltävien tekijöiden on osoitettu olevan yhteydessä mielenterveyden häiriöiden kehittymiseen. Kiinnostus myös kaksisuuntaisen mielialahäiriön mahdollisten pre- ja perinataaliajan riskitekijöiden löytämiseksi on lisääntynyt. Väitöskirjatyön tavoitteena oli kuvata Finnish Prenatal Study of Bipolar Disorders (FIPS-B) -tutkimuksen tutkimusasetelma ja otoksen väestöpohjaisia ominaisuuksia. Lisäksi tavoitteena oli tutkia vanhempien iän ja ikäeron, perinataaliajan tekijöiden sekä äidin raskaudenaikaisen tupakoinnin yhteyttä kaksisuuntaiseen mielialahäiriöön. Väitöskirjatyö perustuu FIPS-B -tutkimukseen. Tutkimus on pesitetty tapausverrokkitutkimus, joka hyödyntää kansallisia rekisteritietoja. Tapaukset olivat Suomessa 1.1.1983–31.12.1998 syntyneitä henkilöitä, joille oli 31.12.2008 mennessä annettu kaksisuuntaisen mielialahäiriön diagnoosi kansallisessa hoitoilmoitus-rekisterissä. Väestörekisterikeskuksesta poimitut verrokit olivat henkilöitä, joilla ei ollut kaksisuuntaisen mielialahäiriön tai skitsofreniaryhmän diagnooseja. Tapaukset ja kutakin tutkittavaa varten poimitut kaksi verrokkia olivat kaltaistettuja iän, sukupuolen ja syntymäajan (+/- 30 päivää) sekä asuinpaikkakunnan suhteen. Asuinpaikkakunta määriteltiin sen mukaan, missä tutkittava oli saanut ensimmäisen kerran kaksisuuntaisen mielialahäiriön diagnoosin. Riskitekijöiden ja kaksisuuntaisen mielialahäiriön yhteyttä tutkittiin ehdollisen logistisen regressioanalyysin avulla. Tutkimus käsitti 1887 kaksisuuntaisen mielialahäiriön diagnoosin saanutta tapausta sekä 3774 verrokkia. Tapausten keski-ikä diagnoosin asettamisen hetkellä oli 19.3 vuotta ja naisten osuus kaikista tapauksista oli 68 %. Matalimmin koulutettujen äitien jälkeläisillä oli korkein todennäköisyys sairastua kaksisuuntaiseen mielialahäiriöön. Itä- ja Etelä-Suomessa syntyminen lisäsi todennäköisyyttä sairastua kaksisuuntaiseen mielialahäiriöön. Korjaamattomassa analyysissä havaittiin U-muotoinen yhteys kaksisuuntaisen mielialahäiriön ja isän iän välillä. Äidin iällä, eikä vanhempien ikäerolla ollut yhteyttä kaksisuuntaiseen mielialahäiriöön. Syntyminen suunnitellulla keisarinleikkauksella oli yhteydessä kaksisuuntaiseen mielialahäiriöön. Äidin raskaudenaikainen tupakointi ei ollut yhteydessä kaksisuuntaiseen mielialahäiriöön monimuuttuja-analyyseissä. Syntymäpaikka ja äidin koulutustaso olivat yhteydessä kaksisuuntaiseen mielialahäiriöön. Sekä isän alhainen että korkea ikä olivat yhteydessä kaksisuuntaiseen mielialahäiriöön. Useimmat perinataaliajan komplikaatiot tai äidin raskaudenaikainen tupakointi eivät olleet yhteydessä kaksisuuntaiseen mielialahäiriöön. Tämän väitöskirjatutkimuksen löydökset ja aikaisempi kirjallisuus viittaavat siihen, että pre- ja perinataaliriskitekijöiden merkitys psykiatristen häiriöiden välillä vaihtelee.Siirretty Doriast

Prenatala riskfaktorer för neuropsykiatriska störningar

Neuropsykiatriska störningar (neuropsyciatric disorders, NPD) hör globalt sett till de vanligasteorsakerna till mortalitet och morbiditet. Ärftliga faktorer inverkar starkt på risken att utvecklaNPD, men det faktum att konkordansen mellan identiska tvillingar inte är 100 procenttyder på att också miljöfaktorer spelar en roll. De senaste tio åren har intresset ökat för hurprenatala och perinatala riskfaktorer inverkar, till exempel gestationsålder och obstetriskakomplikationer, föräldrarnas ålder samt mammans hälsa och riskbeteenden, så som rökning.Denna översiktsartikel ger en bild av litteraturen på området samt av möjliga mekanismeroch riskfaktorernas kliniska och samhälleliga betydelse med avseende på NPD. Prematuritet,nyfödda som är små för tiden (SGA) och förlossning med kejsarsnitt anses korrelera med ökadrisk för NPD. Pappans ålder, mammans ålder och åldersskillnad mellan föräldrarna har fleragånger visats öka risken för NPD. Mammans rökning under graviditeten har visats vara en avde viktiga riskfaktorer för NPD som kan förebyggas. Den potentiella inverkan av framsteg inomneonatalvården, föräldraskapets demografi som är stadd i förändring och utmaningar medforskning om mammans rökande diskuteras också.</p

Relative age within the school year and diagnosis of attention-deficit hyperactivity disorder: a nationwide population-based study

Background There are mixed findings on the relationship between ADHD and younger relative age in class. This study examines whether relative age is associated with ADHD diagnosis in a country where treatment prevalence rates are low and whether any such association has changed over time or relates to comorbid disorders. Methods Using nationwide population-based registers, all Finnish children born between 1991 and 2004 who were diagnosed with ADHD from age 7 years onwards (school starting age), between 1998 and 2011, were identified (n=6136). Incidence ratios (IRs) were used to examine the inter-relationships between relative age, actual age at ADHD diagnosis, and year of diagnosis (1998-2003 vs. 2004-2011). Findings The cumulative incidence of ADHD diagnosis was greatest for younger children within the schoolyear - IRs of 1.26 (boys) and 1.31 (girls). The association between relative age and ADHD diagnosis reflected children diagnosed before the age of 10 years. The strength of this association increased during recent years – for 2004-2011, IRs were 1.37 (95% CI 1.24,1.53) for May-August and 1.64 (95% CI 1.48,1.81) for September-December compared with January-April births (oldest). The relative age effect was not explained by comorbid disorders. Interpretation In a health service system with low prescribing rates for ADHD, younger relative age is associated with an increased likelihood of receiving a clinical diagnosis of ADHD. This influence has increased in recent years. Teachers, parents and clinicians should take relative age into account when considering the possibility of ADHD in a child or encountering a child with a pre-existing diagnosis

Parental immigration and offspring post-traumatic stress disorder : A nationwide population-based register study

Objectives: The aim of this study was to investigate the association between parental immigration status and a diagnosis of post-traumatic stress disorder (PTSD) in their offspring. Methods: This nested matched case-control study was based on a Finnish national birth cohort for 1987-2010 and cases were diagnosed with PTSD by 2012 from the Care Register for Health Care. We identified 3639 cases and 14,434 controls individually matched for gender, place and date of birth ( +/- 30 days). Conditional logistic regression analyses were conducted to examine the association between parental immigration status, parents' region of birth and time since paternal immigration, and PTSD after controlling for confounding factors. Results: The likelihood of being diagnosed with PTSD was significantly increased among children with an immigrant father (OR 1.8, 95% CI 1.3 - 2.4) than those with two Finnish parents and one immigrant mother. There was no significant association between having an immigrant mother or two immigrant parents and receiving a diagnosis of PTSD. The likelihood of being diagnosed with PTSD was increased if the children's fathers had migrated less than five years before their birth (OR 1.4, 95% CI 1.03 - 1.9) and if their immigrant fathers had been born in North Africa or the Middle East (OR 2.1, 95% CI 1.4 - 3.3). Limitations: The sample included a heterogeneous migrant group without information on the reason for migration. The cases were identified from hospital diagnosis that may have only included severe cases. Conclusion: The increased likelihood of a diagnosis of PTSD underlines the need for psychosocial services among second-generation immigrants.Peer reviewe

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

Peer reviewe

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

Abstract 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. Keywords: Adolescent; Depression; Earthquake; Longitudinal study; Post-traumatic stress disorder. © The Author(s) 2021publishedVersionpublishedVersio

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.Peer reviewe

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.</div

Risk for Premature Mortality and Intentional Self-harm in Autism Spectrum Disorders

To examine the risk for premature mortality and intentional self-harm in autism spectrum disorders (ASD). Based on a national birth cohort. Children born in 1987-2005, diagnosed with ASD by 2007 (n = 4695) were matched with four non-ASD subjects (n = 18,450) and followed until 2015 for mortality and intentional self-harm. The risk among ASD subjects was elevated only for natural cause of death. The risk for intentional self-harm was increased in the unadjusted analyses, but decreased to non-significant after adjusting for comorbid psychiatric disorders. ASD subjects are at increased risk for premature mortality due to natural causes of death. While ASD subjects die of suicide and present with more self-harm, the association is explained by comorbid psychiatric disorders.Peer reviewe