Susanna Hinkka-Yli-Salomäki

Elevated Maternal C-Reactive Protein and Increased Risk of Schizophrenia in a National Birth Cohort

OBJECTIVE The objective of the present study was to investigate an association between early gestational C-reactive protein, an established inflammatory biomarker, prospectively assayed in maternal sera, and schizophrenia in a large, national birth cohort with an extensive serum biobank. METHOD A nested case-control design from the Finnish Prenatal Study of Schizophrenia cohort was utilized. A total of 777 schizophrenia cases (schizophrenia, N=630; schizoaffective disorder, N=147) with maternal sera available for C-reactive protein testing were identified and matched to 777 control subjects in the analysis. Maternal C-reactive protein levels were assessed using a latex immunoassay from archived maternal serum specimens. RESULTS Increasing maternal C-reactive protein levels, classified as a continuous variable, were significantly associated with schizophrenia in offspring (adjusted odds ratio=1.31, 95% confidence interval=1.10-1.56). This finding remained significant after adjusting for potential confounders, including maternal and parental history of psychiatric disorders, twin/singleton birth, urbanicity, province of birth, and maternal socioeconomic status. CONCLUSIONS This finding provides the most robust evidence to date that maternal inflammation may play a significant role in schizophrenia, with possible implications for identifying preventive strategies and pathogenic mechanisms in schizophrenia and other neurodevelopmental disorders.

Pregnancy Complications Following Prenatal Exposure to SSRIs or Maternal Psychiatric Disorders: Results From Population-Based National Register Data

OBJECTIVE Using national register data, the authors examined the relationship between prenatal selective serotonin reuptake inhibitor (SSRI) treatment and pregnancy complications, accounting for psychiatric diagnoses related to SSRI use. METHOD This was a population-based prospective birth cohort study using national register data. The sampling frame included 845,345 offspring, representing all singleton live births in Finland between 1996 and 2010. Pregnancies were classified as exposed to SSRIs (N=15,729), unexposed to SSRIs but with psychiatric diagnoses (N=9,652), and unexposed to medications and psychiatric diagnoses (N=31,394). Pregnancy outcomes in SSRI users were compared with those in the unexposed groups. RESULTS Offspring of mothers who received SSRI prescriptions during pregnancy had a lower risk for late preterm birth (odds ratio=0.84, 95% CI=0.74-0.96), for very preterm birth (odds ratio=0.52, 95% CI=0.37-0.74), and for cesarean section (odds ratio=0.70, 95% CI=0.66-0.75) compared with offspring of mothers unexposed to medications but with psychiatric disorders. In contrast, in SSRI-treated mothers, the risk was higher for offspring neonatal complications, including low Apgar score (odds ratio=1.68, 95% CI=1.34-2.12) and monitoring in a neonatal care unit (odds ratio=1.24, 95% CI=1.14-1.35). Compared with offspring of unexposed mothers, offspring of SSRI-treated mothers and mothers unexposed to medications but with psychiatric disorders were both at increased risk of many adverse pregnancy outcomes, including cesarean section and need for monitoring in a neonatal care unit. CONCLUSIONS In a large national birth cohort, treatment of maternal psychiatric disorders with SSRIs during pregnancy was related to a lower risk of preterm birth and cesarean section but a higher risk of neonatal maladaptation. The findings provide novel evidence for a protective role of SSRIs on some deleterious reproductive outcomes, possibly by reducing maternal depressive symptoms. The divergent findings suggest that clinical decisions on SSRI use during pregnancy should be individualized, taking into account the mothers psychiatric and reproductive history.

Obstetric Risk Factors and Autism Spectrum Disorders in Finland

OBJECTIVE To examine the relationship between obstetric risk factors and childhood autism, Asperger syndrome, and other pervasive developmental disorders (PDDs). STUDY DESIGN Registry-based case-control study from all singleton births in Finland from 1990-2005. Cases with childhood autism, Asperger syndrome, or PDD (n = 4713) were identified from the Finnish Hospital Discharge Register. Each case was matched to 4 controls on sex, date of birth, and place of birth. Information on obstetric risk factors was from the Finnish Medical Birth Register. Conditional logistic regression models were used for statistical analyses. RESULTS When adjusted with confounders, childhood autism was associated with maternal high blood pressure (OR 1.49, 95% CI 1.1-2.1, P = .018), Apgar scores less than 7 (1 minute, OR 1.46, 95% CI 1.1-2.0, P = .021), and neonatal treatment with monitoring (OR 1.40, 95% CI 1.02-1.9, P = .038). PDD was associated with induced labor (OR 1.25 95% CI 1.1-1.5, P = .007), planned cesarean delivery (OR 1.34, 95% CI 1.1-1.7, P = .009), 1-minute Apgar scores 7-8 ( OR 1.22, 95% CI 1.1-1.4, P = .008) and less than 7 (OR 1.34, 95% CI 1.03-1.8, P = .032), and neonatal intensive care unit treatment (OR 1.52, 95% CI 1.2-2.0, P = .003). Asperger syndrome was associated only with 1-minute Apgar scores 7-8 (OR 1.19, 95% CI 1.03-1.4, P = .018). CONCLUSIONS Low Apgar scores as well as conditions requiring neonatal special follow-up are important risk factors for childhood autism and PDD. These findings suggest that fetal distress is a potential risk factor for these disorders, but not for Asperger syndrome.

Maternal serum persistent organic pollutants in the Finnish Prenatal Study of Autism: A pilot study

Recent research emphasizes the contribution of environmental as well as genetic factors to the etiology of autism but studies testing associations between chemical exposures and autism have been limited. Prenatal exposure to persistent organic pollutants (POPs) has previously been associated with decrements in cognitive and developmental performance. We conducted a pilot study in the Finnish Prenatal Study of Autism (FiPS-A). Seventy-five cases with autism and 75 controls matched on sex, birth year, urbanization and maternal age were sampled from first-born children in the Finnish Maternity Cohort, which includes over 1million births. The study sample included births occurring from 1991 to 2000. Subjects were followed up for autism through 2007. DDT, DDE, PCB-118, PCB-138, PCB-153, PCB-156, PCB-170, PCB-180, hexachlorobenzene, and BDE-47 were measured in archived maternal serum samples taken during pregnancy using gas chromatography-high resolution mass spectrometry. Correlations between pollutant measures were assessed and mechanistically-related weighting schemes for summarizing PCB levels were compared. Case and control differences were assessed using graphical and statistical methods. All analytes, with the exception of DDT and BDE-47, were detected above the limit of quantification in all samples. The correlation between levels of individual PCB congeners and weighted summary measures was high (0.71-1.00). Paired t-tests revealed no significant differences between cases and controls for log-transformed mean values of any analyte; however, in an adjusted model the odds ratios for autism were 1.91 (p=0.29) and 1.79 (p=0.36) respectively, for subjects with total PCBs and DDE above the 90th percentile of control values. Levels of prenatal PCB exposure in FIPS-A were similar to the levels which previously correlated with poorer neurodevelopmental measures in other populations. Further study in a larger sample will be required to fully determine whether exposure to high POP levels is associated with autism diagnosis in the population.

Internet-Assisted Parent Training Intervention for Disruptive Behavior in 4-Year-Old Children: A Randomized Clinical Trial

IMPORTANCE There is a large gap worldwide in the provision of evidence-based early treatment of children with disruptive behavioral problems. OBJECTIVE To determine whether an Internet-assisted intervention using whole-population screening that targets the most symptomatic 4-year-old children is effective at 6 and 12 months after the start of treatment. DESIGN, SETTING, AND PARTICIPANTS This 2-parallel-group randomized clinical trial was performed from October 1, 2011, through November 30, 2013, at a primary health care clinic in Southwest Finland. Data analysis was performed from August 6, 2015, to December 11, 2015. Of a screened population of 4656 children, 730 met the screening criteria indicating a high level of disruptive behavioral problems. A total of 464 parents of 4-year-old children were randomized into the Strongest Families Smart Website (SFSW) intervention group (n = 232) or an education control (EC) group (n = 232). INTERVENTIONS The SFSW intervention, an 11-session Internet-assisted parent training program that included weekly telephone coaching. MAIN OUTCOMES AND MEASURES Child Behavior Checklist version for preschool children (CBCL/1.5-5) externalizing scale (primary outcome), other CBCL/1.5-5 scales and subscores, Parenting Scale, Inventory of Callous-Unemotional Traits, and the 21-item Depression, Anxiety, and Stress Scale. All data were analyzed by intention to treat and per protocol. The assessments were made before randomization and 6 and 12 months after randomization. RESULTS Of the children randomized, 287 (61.9%) were male and 79 (17.1%) lived in other than a family with 2 biological parents. At 12-month follow-up, improvement in the SFSW intervention group was significantly greater compared with the control group on the following measures: CBCL/1.5-5 externalizing scale (effect size, 0.34; P < .001), internalizing scale (effect size, 0.35; P < .001), and total scores (effect size, 0.37; P < .001); 5 of 7 syndrome scales, including aggression (effect size, 0.36; P < .001), sleep (effect size, 0.24; P = .002), withdrawal (effect size, 0.25; P = .005), anxiety (effect size, 0.26; P = .003), and emotional problems (effect size, 0.31; P = .001); Inventory of Callous-Unemotional Traits callousness scores (effect size, 0.19; P = .03); and self-reported parenting skills (effect size, 0.53; P < .001). CONCLUSIONS AND RELEVANCE The study reveals the effectiveness and feasibility of an Internet-assisted parent training intervention offered for parents of preschool children with disruptive behavioral problems screened from the whole population. The strategy of population-based screening of children at an early age to offering parent training using digital technology and telephone coaching is a promising public health strategy for providing early intervention for a variety of child mental health problems. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01750996.

Maternal thyroid autoantibody and elevated risk of autism in a national birth cohort

OBJECTIVE Autoimmune disruption may contribute to risk for autism; however, since previous studies relied upon clinical diagnoses, exposure misclassification and recall bias are limitations. Thyroid peroxidase antibody (TPO-Ab) is an autoantibody involved in autoimmune thyroiditis. We aimed to test the a priori hypothesis that positivity to maternal serum TPO-Ab (TPO-Ab+) (defined as >156 IU/ml) during pregnancy is related to childhood autism. METHOD The study was based on a nested case-control design of the Finnish Prenatal Study of Autism (FiPS-A), a national birth cohort that includes prospectively drawn archived maternal serum specimens from virtually the entire pregnant population of Finland beginning in 1983. Cases of childhood autism (ICD-10F84.0) born from 1987 to 2005 were ascertained by performing linkages between national birth and inpatient/outpatient registries. All diagnosed cases in Finland over the birth years, and comparison subjects without ASD or severe/profound intellectual disability were matched 1:1 on date of birth, sex, birthplace, and residence in Finland. Maternal serum specimens were assayed in 967 matched case-control pairs for TPO-Ab by a chemiluminescent microparticle immunoassay blind to case/control status. Data were analyzed by conditional logistic regression for matched sets. RESULTS The prevalence of maternal TPO-Ab+ was significantly increased in pregnancies giving rise to autism cases (6.15%) compared to controls (3.54%). The odds of autism were increased by nearly 80% among offspring of mothers who were TPO-Ab+ during pregnancy (OR=1.78, 95% CI=1.16-2.75, p=0.009), compared to mothers negative for this autoantibody. There was also a significant relationship between maternal TPO-Ab defined as a continuous variable and odds of autism (OR=1.09, 95% CI=1.01, 1.17, p=0.02). Measures of maternal thyroid hormones did not differ between groups. CONCLUSIONS These findings provide the first biomarker-based evidence that a class of known maternal autoimmune disorders is related to autism in offspring.

Hypothyroxinemia During Gestation and Offspring Schizophrenia in a National Birth Cohort

BACKGROUND Evidence from animal and human studies indicates that thyroid hormone deficiency during early gestation alters brain development. As schizophrenia is associated with prenatal brain insults and premorbid cognitive deficits, we tested the a priori hypothesis that serologically defined maternal thyroid deficiency during early gestation to mid-gestation is associated with schizophrenia in offspring. METHODS The investigation is based on the Finnish Prenatal Study of Schizophrenia, a nested case-control study that included archived maternal sera from virtually all pregnancies since 1983 (N = >1 million). We identified all offspring in the cohort with a diagnosis of schizophrenia based on the national inpatient and outpatient register and matched them on sex, date of birth, and residence in Finland at time of onset of the case to comparison subjects (1:1) from the cohort. Maternal sera of 1010 case-control pairs were assessed for free thyroxine, and sera of 948 case-control pairs were assessed for thyroid-stimulating hormone. RESULTS Maternal hypothyroxinemia (free thyroxine ≤10th percentile, normal thyroid-stimulating hormone) was associated with an increased odds of schizophrenia (odds ratio = 1.75, 95% confidence interval = 1.22-2.50, p = .002). When adjusted for maternal psychiatric history, province of birth, and maternal smoking during pregnancy, the association remained significant (odds ratio = 1.70, 95% confidence interval = 1.13-2.55, p = .010). CONCLUSIONS In a large, national birth cohort, prospectively documented hypothyroxinemia during early gestation to mid-gestation was associated with increased odds of schizophrenia in offspring. This information can inform translational studies of maternal hypothyroxinemia examining molecular and cellular deviations relevant to schizophrenia.

Association of Selective Serotonin Reuptake Inhibitor Exposure During Pregnancy With Speech, Scholastic, and Motor Disorders in Offspring

Importance Speech/language, scholastic, and motor disorders are common in children. It is unknown whether exposure to selective serotonin reuptake inhibitors (SSRIs) during pregnancy influences susceptibility to these disorders. Objective To examine whether SSRI exposure during pregnancy is associated with speech/language, scholastic, and motor disorders in offspring up to early adolescence. Design, Setting, and Participants This prospective birth cohort study examined national population-based register data in Finland from 1996 to 2010. The sampling frame includes 845 345 pregnant women and their singleton offspring with data on maternal use of antidepressants and depression-related psychiatric disorders during pregnancy. Exposures There were 3 groups of offspring: 15 596 were in the SSRI-exposed group, ie, had mothers diagnosed as having depression-related psychiatric disorders with a history of purchasing SSRIs during pregnancy; 9537 were in the unmedicated group, ie, had mothers diagnosed as having depression-related psychiatric disorders without a history of purchasing SSRIs during pregnancy; and 31 207 were in the unexposed group, ie, had mothers without a psychiatric diagnosis or a history of purchasing SSRIs. Main Outcomes and Measures Cumulative incidence of speech/language, scholastic, or motor disorders (829, 187, and 285 instances, respectively) from birth to 14 years. All hypotheses tested were formulated before data collection. Results Of the 56 340 infants included in the final cohort, 28 684 (50.9%) were male and 48 782 (86.6%) were 9 years or younger. The mean (SD) ages of children at diagnosis were 4.43 (1.67), 3.55 (2.67), and 7.73 (2.38) for speech/language, scholastic, and motor disorders, respectively. Offspring of mothers who purchased SSRIs at least twice during pregnancy had a significant 37% increased risk of speech/language disorders compared with offspring in the unmedicated group. The cumulative hazard of speech/language disorders was 0.0087 in the SSRI-exposed group vs 0.0061 in the unmedicated group (hazard ratio, 1.37; 95% CI, 1.11-1.70; P = .004). There was a significantly increased risk of these disorders in offspring in the SSRI-exposed and unmedicated groups compared with offspring in the unexposed group. For scholastic and motor disorders, there were no differences between offspring in the SSRI-exposed group and in the unmedicated group. Conclusions and Relevance Exposure to SSRIs during pregnancy was associated with an increased risk of speech/language disorders. This finding may have implications for understanding associations between SSRIs and child development.

Parental age and the risk of attention-deficit/hyperactivity disorder: a nationwide, population-based cohort study.

OBJECTIVE An increasing number of studies has shown an association between parental age and psychiatric disorders. However, there are inconsistent results regarding whether age at parenthood is associated with attention-deficit/hyperactivity disorder (ADHD). The aim of this study is to examine whether low or advanced parental age is associated with ADHD. METHOD In this nested case-control study, we identified 10,409 individuals with ADHD born in Finland during 1991 to 2005 and diagnosed with ADHD between 1995 and 2011, along with 39,125 controls matched on sex, date, and place of birth, from nationwide population-based registers. Conditional logistic regression was used to examine the association between parental age and ADHD in offspring, adjusting for potential confounding due to parental psychiatric history, maternal socioeconomic status, marital status, maternal smoking during pregnancy, number of previous births, and birth weight for gestational age. RESULTS Fathers younger than 20 years had a 1.5-fold (odds ratio [OR] = 1.55, 95% CI = 1.11-2.18, p = .01) increased risk of having offspring with ADHD as compared to fathers aged 25 to 29 years. Mothers of the same age group had a 1.4-fold (OR = 1.41, 95% CI = 1.15-1.72, p =.0009) increased risk. Advanced maternal age was inversely associated with ADHD (OR = 0.79, 95% CI = 0.64-0.97, p = .02). CONCLUSION ADHD was associated with young fathers or mothers at the time of birth. Health professionals working with young parents should be aware of the increased risk of ADHD in offspring. This will improve early detection; however, for the development of preventive measures and appropriate interventions, more information on the developmental pathways is needed.

A nationwide register study of the characteristics, incidence and validity of diagnosed Tourette syndrome and other tic disorders

The aim of this study was to describe the characteristics and incidence rates of diagnosed tic disorders in the Finnish Hospital Discharge Register, including changing incidence rates between 1991 and 2010. We also aimed to validate the diagnoses of Tourettes syndrome recorded in the register.