What predicts citation counts and translational impact in headache research? A machine learning analysis

BACKGROUND

We aimed to develop the first machine learning models to predict citation counts and the translational impact, defined as inclusion in guidelines or policy documents, of headache research, and assess which factors are most predictive.

METHODS

Bibliometric data and the titles, abstracts, and keywords from 8600 publications in three headache-oriented journals from their inception to 31 December 2017 were used. A series of machine learning models were implemented to predict three classes of 5-year citation count intervals (0-5, 6-14 and, >14 citations); and the translational impact of a publication. Models were evaluated out-of-sample with area under the receiver operating characteristics curve (AUC).

RESULTS

The top performing gradient boosting model predicted correct citation count class with an out-of-sample AUC of 0.81. Bibliometric data such as page count, number of references, first and last author citation counts and h-index were among the most important predictors. Prediction of translational impact worked optimally when including both bibliometric data and information from the title, abstract and keywords, reaching an out-of-sample AUC of 0.71 for the top performing random forest model.

CONCLUSION

Citation counts are best predicted by bibliometric data, while models incorporating both bibliometric data and publication content identifies the translational impact of headache research.

Antipsychotic use during pregnancy and risk of specific neurodevelopmental disorders and learning difficulties in children: a multinational cohort study

Background

Antipsychotics are commonly prescribed to treat a range of psychiatric conditions in women of reproductive age and during pregnancy, including schizophrenia, bipolar disorder, anxiety, depression, autism spectrum disorder, and insomnia. This study aimed to evaluate whether children exposed to antipsychotic medication prenatally are at increased risk of specific neurodevelopmental disorders and learning difficulties.

Methods

Our population-based cohort study used nationwide register data (1 January 2000-31 December 2020) on pregnant women diagnosed with a psychiatric disorder and their live-born singletons from Denmark, Finland, Iceland, Norway, and Sweden. Cox proportional hazard regression yielded propensity score-weighted hazard ratios (aHRs) and 95% confidence intervals (CIs) for risk of intellectual-, speech or language-, learning-developmental disorders, and a composite outcome of the listed disorders. We defined poor performance as scoring within the lowest quartile on national school tests in mathematics and language arts. We estimated propensity score-weighted risk ratios (aRRs) using Poisson regression. We analysed data from Denmark separately and pooled results using random effects meta-analysis.

Findings

Among 213,302 children (median follow-up: 6.7 years), 11 626 (5.5%) were exposed to antipsychotics prenatally. Adjusted risk estimates did not suggest an increased risk of neurodevelopmental disorders: aHR of 1.06 (95% CI 0.94-1.20) for the composite outcome, or for poor academic performance: aRR of 1.04 (95% CI 0.91-1.18) in mathematics, and of 1.00 (95% CI 0.87-1.15) in language arts. Results were generally consistent across individual medications, trimesters of exposure, sibling- and sensitivity analyses.

Interpretation

The findings of this large multinational cohort study suggest there is little to no increased risk of child neurodevelopmental disorders or learning difficulties after prenatal exposure to antipsychotics. Our findings can assist clinicians and women managing mental illness during pregnancy.

Funding

This study was funded by the NordForsk Nordic Program on Health and Welfare (Nordic Pregnancy Drug Safety Studies, project No. 83539), by the Research Council of Norway (International Pregnancy Drug Safety Studies, project No. 273366) and by the Research Council of Norway through its Centres of Excellence funding scheme (project No. 262700), and UNSW Scientia Programme Awards (PS46019, PS46019-A).

Prescribing patterns for higher dose folic acid in pregnant women with epilepsy treated with antiseizure medication

OBJECTIVE

This study was undertaken to characterize the use of higher doses of folic acid (≥1 mg daily) in relation to pregnancy in Denmark, Norway, and Sweden in women with epilepsy treated with antiseizure medication (ASM).

METHODS

In this observational study, we used data from national medical birth, patient, and prescription registers in Denmark, Norway, and Sweden to retrospectively identify pregnancies in women with epilepsy treated with ASM from 2006 to 2017. The proportion of higher dose folic acid supplementation in pregnancies among women receiving ASM for epilepsy was calculated according to country of origin, time period, and type of ASM. Logistic regression with restricted cubic splines was used to model country-specific time trends.

RESULTS

Among a total of 2 748 882 pregnancies, we identified 8695 (.3%) pregnancies after restricting the population to women with ASM-treated epilepsy. A prescription for higher dose folic acid was filled in 4719 (54.3%) of these pregnancies. The proportion supplemented with higher dose folic acid was highest in Sweden (74.3%) and lower in Norway (41.4%) and Denmark (34.3%). Furthermore, we observed a decreasing trend of higher dose folic acid use in Denmark and Norway from year 2012 to 2017. Among those who used higher dose folic acid, 42% did not start preconception supplementation with higher dose folic acid.

SIGNIFICANCE

Supplementation with higher dose folic acid occurred in approximately half of pregnancies in women with ASM-treated epilepsy, with many not starting supplementation until after becoming pregnant. Considerable variability was observed in the use of higher dose folic acid across the countries, despite similar population characteristics and health care systems. Future guidelines should be simplified with clear recommendations developed in a collaborative manner by relevant specialists including neurologists, obstetricians, pediatricians, and public health specialists to enhance real-world applicability.

Prenatal exposure to antiseizure medications and fetal growth: a population-based cohort study from the Nordic countries

Background

The short- and long-term consequences of restricted fetal growth cause considerable concern, and how prenatal exposure to different antiseizure medications (ASMs) affects fetal growth remains uncertain.

Methods

This was a population-based cohort study of liveborn singleton children born in Denmark, Finland, Iceland, Norway, and Sweden from 1996 to 2017. Prenatal exposure was defined as maternal filling of prescriptions for ASM during pregnancy registered in national prescription registries and primary outcomes were adjusted odds ratios (aORs) of microcephaly or being born small for gestational age.

Findings

We identified 4,494,918 children (males: 51.3%, 2,306,991/4,494,918), including 38,714 (0.9%) children of mothers with epilepsy. In the overall population, prenatal monotherapy exposure with carbamazepine (aOR: 1.25 (95% CI: 1.12-1.40)), pregabalin (aOR: 1.16 (95% CI: 1.02-1.31)), oxcarbazepine (aOR: 1.48 (95% CI: 1.28-1.71)), clonazepam (aOR: 1.27 (95% CI: 1.10-1.48)), and topiramate (aOR: 1.48 (95% CI: 1.18-1.85)) was associated with risk of being born small for gestational age, and carbamazepine was associated with microcephaly (aOR: 1.43 (95% CI: 1.17-1.75)). In children of mothers with epilepsy, prenatal exposure to carbamazepine (aOR: 1.27 (95% CI: 1.11-1.47)), oxcarbazepine (aOR: 1.42 (95% CI: 1.18-1.70)), clonazepam (aOR: 1.40 (95% CI: 1.03-1.89)), and topiramate (aOR: 1.86 (95% CI: 1.36-2.54)) was associated with being born small for gestational age; carbamazepine, with microcephaly (aOR: 1.51 (95% CI: 1.17-1.95)). No associations with small for gestational age and microcephaly were identified after prenatal exposure to lamotrigine, valproate, gabapentin, levetiracetam, phenobarbital, acetazolamide, phenytoin, clobazam, primidone, zonisamide, vigabatrin, ethosuximide and lacosamide, but except for lamotrigine, valproate, gabapentin, and levetiracetam, numbers of exposed children were small.

Interpretation

Prenatal exposure to carbamazepine, oxcarbazepine, clonazepam, and topiramate was associated with increased risk of being born small for gestational age in both the overall population and in children of women with epilepsy suggesting that prenatal exposure to these drugs is associated with fetal growth restriction.

Funding

The NordForsk Nordic Program on Health and Welfare (83539), the Independent Research Fund Denmark (1133-00026B), the Danish Epilepsy Association, the Central Denmark Region, the Novo Nordisk Foundation (NNF16OC0019126 and NNF22OC0075033), and the Lundbeck Foundation (R400-2022-1205).

Transient Neonatal Myasthenia Gravis as a Common Complication of a Rare Disease: A Systematic Review

Myasthenia gravis (MG) is a rare autoimmune disease. Transient neonatal myasthenia gravis (TNMG) is caused by pathogenic maternal autoantibodies that cross the placenta and disrupt signaling at the neuromuscular junction. This is a systematic review of this transient immunoglobulin G (IgG)-mediated disease. TNMG affects 10-20% of children born to mothers with MG. The severity of symptoms ranges from minor feeding difficulties to life-threatening respiratory weakness. Minor symptoms might go unnoticed but can still interfere with breastfeeding. Acetylcholine-esterase inhibitors and antibody-clearing therapies such as immunoglobulins can be used to treat TNMG, but most children do well with observation only. TNMG is self-limiting within weeks as circulating antibodies are naturally cleared from the blood. In rare cases, TNMG is associated with permanent skeletal malformations or permanent myopathy. The mother's antibodies can also lead to spontaneous abortions. All healthcare professionals meeting pregnant or birthing women with MG or their neonates should be aware of TNMG. TNMG is hard to predict. Reoccurrence is common among siblings. Pre-pregnancy thymectomy and intravenous immunoglobulins during pregnancy reduce the risk. Neonatal fragment crystallizable receptor (FcRn) blocking drugs for MG might reduce TNMG risk.

Prenatal Exposure to Antiseizure Medications and Risk of Epilepsy in Children of Mothers With Epilepsy

Importance

Use of valproate and certain other antiseizure medications (ASMs) in pregnancy is associated with abnormal fetal brain development with potential long-term implications for the child.

Objective

To examine whether use of valproate and other ASMs in pregnancy among mothers with epilepsy is associated with epilepsy risk in their children.

Design, Setting, and Participants

This prospective, population-based register cohort study included singletons born to mothers with epilepsy in Denmark, Finland, Iceland, Norway, and Sweden from January 1, 1996, to December 31, 2017. Data analysis was performed from October 2022 to December 2023.

Exposure

Redeemed prescription for an ASM from 30 days before pregnancy until birth.

Main Outcomes and Measures

The main outcome was epilepsy in children, assessed using International Statistical Classification of Diseases and Related Health Problems, Tenth Revision diagnoses from hospital care. Adjusted hazard ratios (AHRs) and 95% CIs were estimated using Cox proportional hazards regression. Secondary analyses included dose-response analyses, analyses using children of mothers who discontinued ASM prior to pregnancy as the reference, and sibling analyses.

Results

This cohort study included 38 663 children of mothers with epilepsy (19 854 [51.4%] boys). Children were followed up from birth; the mean length of follow-up was 7.2 years (range 0-22 years). Compared with 22 207 children of mothers not using an ASM in pregnancy, increased risks of epilepsy in children of mothers who used valproate in pregnancy (monotherapy: AHR, 2.18; 95% CI, 1.70-2.79; polytherapy: AHR, 2.10; 95% CI, 1.49-2.96) were observed. However, there was no dose-dependent association, and there was a similar risk of epilepsy in siblings who were exposed and unexposed to valproate (AHR, 0.95; 95% CI, 0.50-1.82). Prenatal exposure to topiramate monotherapy was associated with increased risk of epilepsy (AHR, 2.32; 95% CI, 1.30-4.16), and the risk was greater for higher doses, but the risk attenuated in comparisons with children of mothers who discontinued topiramate before pregnancy (AHR, 1.19; 95% CI, 0.26-5.44). Prenatal exposure to clonazepam monotherapy was also associated with increased epilepsy risk (AHR, 1.90; 95% CI, 1.16-3.12), but limited follow-up and low numbers precluded further analyses. No associations were observed for prenatal exposure to lamotrigine (AHR, 1.18; 95% CI, 0.95-1.47), levetiracetam (AHR, 1.28; 95% CI, 0.77-2.14), carbamazepine (AHR, 1.13; 95% CI, 0.85-1.50), or oxcarbazepine (AHR, 0.68; 95% CI, 0.44-1.05).

Conclusions and Relevance

In this cohort study of children born to mothers with epilepsy, the associations found between prenatal exposure to certain ASMs and the child's risk of epilepsy did not persist in sensitivity analyses, suggesting that maternal ASM use in pregnancy may not increase epilepsy risk in children beyond that associated with the maternal epilepsy itself. These findings are reassuring for women in need of treatment with ASM in pregnancy.

Adverse Childhood Experiences and the Risk of Multiple Sclerosis Development: A Review of Potential Mechanisms

Adverse childhood experiences (ACEs), such as abuse, neglect, and household dysfunction, contribute to long-term systemic toxic stress and inflammation that may last well into adulthood. Such early-life stressors have been associated with increased susceptibility to multiple sclerosis (MS) in observational studies and with the development of experimental autoimmune encephalomyelitis in animal models. In this review, we summarize the evidence for an ACE-mediated increase in MS risk, as well as the potential mechanisms for this association. ACEs dysregulate neurodevelopment, stress responses, and immune reactivity; they also alter the interplay between the immune system and neural networks. All of this may be relevant for MS risk. We further discuss how ACEs induce epigenetic changes and how the toxic stress caused by ACEs may reactivate the Epstein-Barr Virus (EBV), a key risk factor for MS. We conclude by suggesting new initiatives to obtain further insights into this topic.

Comparative Risk of Major Congenital Malformations With Antiseizure Medication Combinations vs Valproate Monotherapy in Pregnancy

BACKGROUND AND OBJECTIVES

Valproate should be avoided in pregnancy, but it is the most effective drug for generalized epilepsies. Alternative treatment may require combinations of other drugs. Our objectives were to describe first trimester use of antiseizure medication (ASM) combinations that are relevant alternatives to valproate and determine whether specific combinations were associated with a lower risk of major congenital malformations (MCM) compared with valproate monotherapy.

METHODS

We conducted a population-based cohort study using linked national registers from Denmark, Finland, Iceland, Norway, and Sweden and administrative health care data from the United States and New South Wales, Australia. We described first trimester use of ASM combinations among pregnant people with epilepsy from 2000 to 2020. We compared the risk of MCM after first trimester exposure to ASM combinations vs valproate monotherapy and low-dose valproate plus lamotrigine or levetiracetam vs high-dose valproate (≥1,000 mg/d). We used log-binomial regression with propensity score weights to calculate adjusted risk ratios (aRRs) and 95% CIs for each dataset. Results were pooled using fixed-effects meta-analysis.

RESULTS

Among 50,905 pregnancies in people with epilepsy identified from 7.8 million total pregnancies, 788 used lamotrigine and levetiracetam, 291 used lamotrigine and topiramate, 208 used levetiracetam and topiramate, 80 used lamotrigine and zonisamide, and 91 used levetiracetam and zonisamide. After excluding pregnancies with use of other ASMs, known teratogens, or a child diagnosed with MCM of infectious or genetic cause, we compared 587 exposed to lamotrigine-levetiracetam duotherapy and 186 exposed to lamotrigine-topiramate duotherapy with 1959 exposed to valproate monotherapy. Pooled aRRs were 0.41 (95% CI 0.24-0.69) and 1.26 (0.71-2.23), respectively. Duotherapy combinations containing low-dose valproate were infrequent, and comparisons with high-dose valproate monotherapy were inconclusive but suggested a lower risk for combination therapy. Other combinations were too rare for comparative safety analyses.

DISCUSSION

Lamotrigine-levetiracetam duotherapy in first trimester was associated with a 60% lower risk of MCM than valproate monotherapy, while lamotrigine-topiramate was not associated with a reduced risk. Duotherapy with lamotrigine and levetiracetam may be favored to treat epilepsy in people with childbearing potential compared with valproate regarding MCM, but whether this combination is as effective as valproate remains to be determined.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that in people with epilepsy treated in the first trimester of pregnancy, the risk of major congenital malformations is lower with lamotrigine-levetiracetam duotherapy than with valproate alone, but similar with lamotrigine-topiramate.

High-dose folic acid and cancer risk; unjustified concerns by von Wrede and colleagues regarding our paper

Women using antiseizure medication in pregnancy are often advised to use high doses of folic acid supplements (1mg to 5 mg) to reduce the risk of teratogenicity. Recently, we published a report showing an association between maternal prescription fill of high dose folic acid in relation to pregnancy and childhood cancer in the offspring. The report has sparked a debate about which dose of folic acid that should be recommended in pregnancy in women in need of antiseizure medication. In this Commentary, we explain our findings and the method used in our report, and answer recent questions that have emerged.

Prenatal Exposure to Antiseizure Medication and Incidence of Childhood- and Adolescence-Onset Psychiatric Disorders

Importance

Prenatal antiseizure medication (ASM) exposure has been associated with adverse early neurodevelopment, but associations with a wider range of psychiatric end points have not been studied.

Objective

To examine the association between prenatal exposure to ASM with a spectrum of psychiatric disorders in childhood and adolescence in children of mothers with epilepsy.

Design, Setting, and Participants

This prospective, population-based register study assessed 4 546 605 singleton children born alive in Denmark, Finland, Iceland, Norway, and Sweden from January 1, 1996, to December 31, 2017. Of the 4 546 605 children, 54 953 with chromosomal disorders or uncertain birth characteristics were excluded, and 38 661 children of mothers with epilepsy were identified. Data analysis was performed from August 2021 to January 2023.

Exposures

Prenatal exposure to ASM was defined as maternal prescription fills from 30 days before the first day of the last menstrual period until birth.

Main Outcomes and Measures

The main outcome measure was diagnosis of psychiatric disorders (a combined end point and 13 individual disorders). Estimated adjusted hazard ratios (aHRs) using Cox proportional hazards regression and cumulative incidences with 95% CIs are reported.

Results

Among the 38 661 children of mothers with epilepsy (16 458 [42.6%] exposed to ASM; 19 582 [51.3%] male; mean [SD] age at the end of study, 7.5 [4.6] years), prenatal valproate exposure was associated with an increased risk of the combined psychiatric end point (aHR, 1.80 [95% CI, 1.60-2.03]; cumulative risk at 18 years in ASM-exposed children, 42.1% [95% CI, 38.2%-45.8%]; cumulative risk at 18 years in unexposed children, 31.3% [95% CI, 28.9%-33.6%]), which was driven mainly by disorders within the neurodevelopmental spectrum. Prenatal exposure to lamotrigine, carbamazepine, and oxcarbazepine was not associated with an increased risk of psychiatric disorders, whereas associations were found for prenatal exposure to topiramate with attention-deficit/hyperactivity disorder (aHR, 2.38; 95% CI, 1.40-4.06) and exposure to levetiracetam with anxiety (aHR, 2.17; 95% CI, 1.26-3.72) and attention-deficit/hyperactivity disorder (aHR, 1.78; 95% CI, 1.03-3.07).

Conclusions and Relevance

Findings from this explorative study strengthen the evidence for the warning against the use of valproate in pregnancy and raise concern of risks of specific psychiatric disorders associated with topiramate and levetiracetam. This study provides reassuring evidence that lamotrigine, carbamazepine, and oxcarbazepine are not associated with long-term behavioral or developmental disorders but cannot rule out risks with higher doses.

Effects of insufficient sleep on sensorimotor processing in migraine: A randomised, blinded crossover study of event related beta oscillations

BACKGROUND

Migraine has a largely unexplained connection with sleep and is possibly related to a dysfunction of thalamocortical systems and cortical inhibition. In this study we investigate the effect of insufficient sleep on cortical sensorimotor processing in migraine.

METHODS

We recorded electroencephalography during a sensorimotor task from 46 interictal migraineurs and 28 controls after two nights of eight-hour habitual sleep and after two nights of four-hour restricted sleep. We compared changes in beta oscillations of the sensorimotor cortex after the two sleep conditions between migraineurs, controls and subgroups differentiating migraine subjects usually having attacks starting during sleep and not during sleep. We included preictal and postictal recordings in a secondary analysis of temporal changes in relation to attacks.

RESULTS

Interictally, we discovered lower beta synchronisation after sleep restriction in sleep related migraine compared to non-sleep related migraine (p=0.006) and controls (p=0.01). No differences were seen between controls and the total migraine group in the interictal phase. After migraine attacks, we observed lower beta synchronisation (p<0.001) and higher beta desynchronisation (p=0.002) after sleep restriction closer to the end of the attack compared to later after the attack.

CONCLUSION

The subgroup with sleep related migraine had lower sensorimotor beta synchronisation after sleep restriction, possibly related to dysfunctional GABAergic inhibitory systems. Sufficient sleep during or immediately after migraine attacks may be of importance for maintaining normal cortical excitability.

Comparative Safety of Antiseizure Medication Monotherapy for Major Malformations

OBJECTIVE

This study was undertaken to examine the comparative safety of antiseizure medication (ASM) monotherapy in pregnancy with respect to risk of major congenital malformations (MCMs), overall and by MCM subtype.

METHODS

We conducted a population-based cohort study using national health register data from Denmark, Finland, Iceland, Norway, and Sweden (1996-2020). We compared pregnancies with first trimester exposure to lamotrigine monotherapy to ASM-unexposed, carbamazepine, valproate, oxcarbazepine, levetiracetam, and topiramate to lamotrigine monotherapy, and stratified monotherapy groups by dose. The outcome was nongenetic MCM and specific subtypes. We estimated adjusted risk ratios (aRRs) and 95% confidence intervals (CIs) with log-binomial regression and propensity score weights.

RESULTS

There was a higher crude risk of any MCM in pregnancies exposed to lamotrigine monotherapy (n = 8,339) compared to ASM-unexposed pregnancies (n = 4,866,362), but not after confounder adjustment (aRR = 0.97, 95% CI = 0.87-1.08). Compared to lamotrigine, there was an increased risk of malformations associated with valproate (n = 2,031, aRR = 2.05, 95% CI = 1.70-2.46) and topiramate (n = 509, aRR = 1.81, 95% CI = 1.26-2.60), which increased in a dose-dependent manner. We found no differences in malformation risk for carbamazepine (n = 2,674, aRR = 0.91, 95% CI = 0.72-1.15), oxcarbazepine (n = 1,313, aRR = 1.09, 95% CI = 0.83-1.44), or levetiracetam (n = 1,040, aRR = 0.78, 95% CI = 0.53-1.13). Valproate was associated with several malformation subtypes, including nervous system, cardiac, oral clefts, clubfoot, and hypospadias, whereas lamotrigine and carbamazepine were not.

INTERPRETATION

Topiramate is associated with an increased risk of MCM similar to that associated with valproate, but lower doses may mitigate the risks for both drugs. Conversely, we found no increased risks for lamotrigine, carbamazepine, oxcarbazepine, or levetiracetam, which is reassuring. ANN NEUROL 2023;93:551-562.

The association between antihypertensive medications and mental health outcomes among Syrian war refugees with stress and hypertension

BACKGROUND

Little is known about the association between antihypertensive drugs with mental health outcomes. We examined the association between the antihypertensive classes and other clinical patient features with symptoms of depression, anxiety, insomnia, and Post-Traumatic Stress Disorder (PTSD) in a cohort of Syrian war refugees with stress and hypertension residing in Jordan.

METHODS

This cross-sectional study recruited hypertensive Syrian refugees with stress. Depression severity was assessed using the Patient Health Questionnaire-9, anxiety was measured by The General Anxiety Disorder-7, the Insomnia Severity Index was used to evaluate sleep quality and PTSD was measured using Davidson Trauma Scale. To investigate the association between the different classes of antihypertensive medication and mental health outcomes we used multivariable regression models.

RESULTS

Of the 492 participants, 251 were men (51%), 234 (47.6%) were on β-blockers, 141 (28.7%) on diuretics, and 209 (42.5%) on Angiotensin Converting Enzyme Inhibitors (ACEIs)/Angiotensin Receptor Blockers (ARBs). Although the multivariate regression revealed the different classes of antihypertensives are not associated with mental health symptoms, however, physical activity is associated with lower adjusted odds for symptoms of depression (0.68 (0.46-0.99), p = 0.04), anxiety (0.60 (0.42-0.85),p = 0.005), insomnia (0.63 (0.44-0.91),p = 0.01) and dyslipidemia (3.48(0.29-6.69),p = 0.03) is associated with higher PTSD symptoms.

LIMITATIONS

The study subjects were not assessed for psychiatric diagnoses clinically. Further, we used a cross-sectional design that does not allow to measure longitudinal changes.

CONCLUSIONS

The association between antihypertensive drugs and mental health symptoms was not evident in the present study. Follow-up future studies are required.

Cancer Risk in Children of Mothers With Epilepsy and High-Dose Folic Acid Use During Pregnancy

Importance

Women with epilepsy are recommended high doses of folic acid before and during pregnancy owing to risk of congenital anomalies associated with antiseizure medications. Whether prenatal exposure to high-dose folic acid is associated with increases in the risk of childhood cancer is unknown.

Objective

To assess whether high-dose folic acid supplementation in mothers with epilepsy is associated with childhood cancer.

Design, Setting, and Participants

Observational cohort study conducted with nationwide registers in Denmark, Norway, and Sweden from 1997 to 2017. Analyses were performed during January 10, 2022, to January 31, 2022. Mother-child pairs were identified in medical birth registers and linked with information from patient, prescription, and cancer registers, as well as with sociodemographic information from statistical agencies, and were categorized by maternal diagnosis of epilepsy. The study population consisted of 3 379 171 children after exclusion of 126 711 children because of stillbirth or missing or erroneous values on important covariates.

Exposures

Maternal prescription fills for high-dose folic acid tablets (≥1 mg daily) between 90 days before pregnancy start and birth.

Main Outcomes and Measures

First onset of childhood cancer at younger than 20 years. Cox proportional hazards models were used to calculate adjusted hazard ratios with corresponding 95% CIs, adjusted for potential confounders. Cumulative incidence at aged 20 years was used as a measure of absolute risk.

Results

The median age at the end of follow-up in the study population of 3 379 171 children was 7.3 years (IQR, 3.5-10.9 years). Among the 27 784 children (51.4% male) born to mothers with epilepsy, 5934 (21.4%) were exposed to high-dose folic acid (mean dose, 4.3 mg), with 18 exposed cancer cases compared with 29 unexposed, producing an adjusted hazard ratio of 2.7 (95% CI, 1.2-6.3), absolute risk if exposed of 1.4% (95% CI, 0.5%-3.6%), and absolute risk if unexposed of 0.6% (95% CI, 0.3%-1.1%). In children of mothers without epilepsy, 46 646 (1.4%) were exposed to high-dose folic acid (mean dose, 2.9 mg), with 69 exposed and 4927 unexposed cancer cases and an adjusted hazard ratio of 1.1 (95% CI, 0.9-1.4; absolute risk, 0.4% [95% CI, 0.3%-0.5%]). There was no association between children born to mothers with epilepsy who were prenatally exposed to antiseizure medications, but not high-dose folic acid, and an increased risk of cancer (absolute risk, 0.6%; 95% CI, 0.2%-1.3%).

Conclusions and Relevance

Prenatal exposure to high-dose folic acid was associated with increased risk of cancer in children of mothers with epilepsy.

Abuse and revictimization in adulthood in multiple sclerosis: a cross-sectional study during pregnancy

Background

Knowledge concerning exposure to abuse in adulthood and in pregnancy in people with multiple sclerosis (MS) is sparse.

Objective

To determine the occurrence of adult abuse and abuse in relation to pregnancy in women with MS and their risk of revictimization (repeated abuse as adults after childhood abuse).

Methods

This cross-sectional study comprised pregnant women from the Norwegian Mother, Father and Child Cohort study. Information on abuse was acquired through self-completed questionnaires. We used logistic regression to estimate adjusted odds ratios (aORs) with 95% confidence intervals (CIs).

Results

We identified 106 women with MS at enrollment through linkage with national health registries. The reference group consisted of 77,278 women without MS. Twenty-seven women (26%) with MS reported any adult abuse compared to 15,491 women (20%) without MS, aOR 1.33 (0.85–2.09). Twenty-two (21%) women with MS reported systematic emotional abuse compared to 13% without MS, aOR 1.75 (1.08–2.83). Ten women (10%) with MS reported sexual abuse, compared to 6% without MS, aOR 1.72 (0.89–3.33). More women with MS reported rape as an adult, aOR 2.37 (1.02–5.49). Women with MS had higher risk of revictimization as adults, after childhood abuse, aOR 2.23 (1.22–4.10). The risk of abuse during pregnancy or 6 months preceding pregnancy was similar between the groups.

Conclusions

Women with MS had increased occurrence of systematic emotional abuse, rape, and revictimization as adults, compared to women without MS.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00415-022-11249-x.

Association of Prenatal Exposure to Antiseizure Medication With Risk of Autism and Intellectual Disability

Importance

Women with epilepsy frequently need antiseizure medication (ASM) to prevent seizures in pregnancy. Risk of neurodevelopmental disorders after prenatal exposure to AMSs is uncertain.

Objective

To determine whether children exposed prenatally to ASMs in monotherapy and duotherapy have increased risk of neurodevelopmental disorders.

Design, Setting, and Participants

The Nordic register-based study of antiepileptic drugs in pregnancy (SCAN-AED) is a population-based cohort study using health register and social register data from Denmark, Finland, Iceland, Norway, and Sweden (1996-2017; analysis performed February 2022). From 4 702 774 alive-born children with available mother-child identities and maternal prescription data, this study included 4 494 926 participants. Children from a multiple pregnancy or with chromosomal disorders or uncertain pregnancy length were excluded (n = 207 848).

Exposures

Prenatal exposure to ASM determined from maternal prescription fills between last menstrual period and birth.

Main Outcomes and Measures

We estimated cumulative incidence at age 8 years in exposed and unexposed children. Cox regression adjusted for potential confounders yielded adjusted hazard ratios (aHRs) with 95% CIs for autism spectrum disorder (ASD), intellectual disability (ID), or any neurodevelopmental disorder (ASD and/or ID).

Results

A total of 4 494 926 children were included; 2 306 993 (51.3%) were male, and the median (IQR) age at end of follow-up was 8 (4.0-12.1) years. Among 21 634 unexposed children of mothers with epilepsy, 1.5% had a diagnosis of ASD and 0.8% (numerators were not available because of personal data regulations in Denmark) of ID by age 8 years. In same-aged children of mothers with epilepsy exposed to topiramate and valproate monotherapy, 4.3% and 2.7%, respectively, had ASD, and 3.1% and 2.4% had ID. The aHRs for ASD and ID after topiramate exposure were 2.8 (95% CI, 1.4-5.7) and 3.5 (95% CI, 1.4-8.6), respectively, and after valproate exposure were 2.4 (95% CI, 1.7-3.3) and 2.5 (95% CI, 1.7-3.7). The aHRs were elevated with higher ASM doses compared with children from the general population. The duotherapies levetiracetam with carbamazepine and lamotrigine with topiramate were associated with increased risks of neurodevelopmental disorders in children of women with epilepsy: levetiracetam with carbamazepine: 8-year cumulative incidence, 5.7%; aHR, 3.5; 95% CI, 1.5-8.2; lamotrigine with topiramate: 8-year cumulative incidence, 7.5%; aHR, 2.4; 95% CI, 1.1-4.9. No increased risk was associated with levetiracetam with lamotrigine (8-year cumulative incidence, 1.6%; aHR, 0.9; 95% CI, 0.3-2.5). No consistently increased risks were observed for neurodevelopmental disorders after prenatal exposure to monotherapy with lamotrigine, levetiracetam, carbamazepin, oxcarbazepine, gapapentin, pregabalin, clonazepam, or phenobarbital.

Conclusions and Relevance

In this cohort study, prenatal exposure to topiramate, valproate, and several duotherapies were associated with increased risks of neurodevelopmental disorders.

Association of adverse childhood experiences with the development of multiple sclerosis

OBJECTIVE

To study whether exposure to childhood emotional, sexual or physical abuse is associated with subsequent multiple sclerosis (MS) development.

METHODS

A nationwide, prospective cohort study based on participants in the Norwegian Mother, Father and Child cohort study. Enrolment took place 1999-2008, with follow-up until 31 December 2018. Childhood abuse before age 18 years was obtained from self-completed questionnaires. We identified MS diagnoses through data-linkage with national health registries and hospital records. The Cox model was used to estimate HRs for MS with 95% CIs, adjusting for confounders and mediators.

RESULTS

In this prospective cohort study, 14 477 women were exposed to childhood abuse and 63 520 were unexposed. 300 women developed MS during the follow-up period. 71 of these (24%) reported a history of childhood abuse, compared with 14 406 of 77 697 (19%) women that did not develop MS. Sexual abuse (HR 1.65, 95% CI 1.13 to 2.39) and emotional abuse (HR 1.40, 95% CI 1.03 to 1.90) in childhood were both associated with an increased risk of developing MS. The HR of MS after exposure to physical abuse was 1.31 (95% CI 0.83 to 2.06). The risk of MS was further increased if exposed to two (HR 1.66, 95% CI 1.04 to 2.67) or all three abuse categories (HR 1.93, 95% CI 1.02 to 3.67).

INTERPRETATION

Childhood sexual and emotional abuse were associated with an increased risk of developing MS. The risk was higher when exposed to several abuse categories, indicating a dose-response relationship. Further studies are needed to identify underlying mechanisms.

Antipsychotic use in pregnancy and risk of attention/deficit-hyperactivity disorder and autism spectrum disorder: a Nordic cohort study

Background

Antipsychotics are increasingly used among women of childbearing age and during pregnancy.

Objective

To determine whether children exposed to antipsychotics in utero are at increased risk of attention-deficit/hyperactivity disorder (ADHD) or autism spectrum disorder (ASD), accounting for maternal diagnoses of bipolar, psychotic and other psychiatric disorders.

Design

Population-based cohort study, including a sibling analysis.

Setting

Nationwide data on all pregnant women and their live-born singletons in Denmark (1997-2017), Finland (1996-2016), Iceland (2004-2017), Norway (2004-2017), and Sweden (2006-2016).

Participants

4 324 086 children were eligible for inclusion to the study cohort.

Intervention

Antipsychotic exposure in utero, assessed by pregnancy trimester, type of antipsychotic, and varying patterns of use.

Main outcome measures

Non-mutually exclusive diagnoses of ADHD and ASD. We used Cox proportional hazard models to calculate hazard ratios (HRs) controlling for maternal psychiatric disorders and other potential confounding factors.

Findings

Among 4 324 086 singleton births, 15 466 (0.4%) were exposed to antipsychotics in utero. During a median follow-up of 10 years, we identified 72 257 children with ADHD and 38 674 children with ASD. Unadjusted HRs were raised for both outcomes but shifted substantially towards the null after adjustment; 1.10 (95%CI 1.00 to 1.27) for ADHD and 1.12 (0.97 to 1.29) for ASD. Adjusted HRs remained consistent by trimester of exposure and type of antipsychotic. Comparing in utero exposure with pre-pregnancy use yielded HRs of 0.74 (0.62 to 0.87) for ADHD and 0.88 (0.70 to 1.10) for ASD. Sibling analyses yielded HRs of 1.14 (0.79 to 1.64) for ADHD and 1.34 (0.75 to 2.39) for ASD.

Discussion

Our findings suggest little or no increased risk of child ADHD or ASD after in utero exposure to antipsychotics.

Clinical implications

Results regarding child neurodevelopment are reassuring for women who need antipsychotics during pregnancy.

Prenatal exposure to valproate and risk of congenital malformations-Could we have known earlier?-A population-based cohort study

OBJECTIVE

Prenatal exposure to the antiseizure medication (ASM) valproate is associated with an increased risk of congenital malformations, but warnings against the use of valproate in pregnancy were not issued until 2009. The objective was to study how early administrative health registers could have identified the teratogenic risk associated with valproate.

METHODS

This was a population-based cohort study of individual-linked data from Danish health care and socioeconomic registers including children born in Denmark between January 1, 1997 and December 31, 2014. Information on ASM use, including valproate, in pregnancy was obtained from the Danish National Prescription Registry. Children identified with major congenital malformations from the Danish National Patient Register and the Danish Register of Causes of Death were included. Using logistic regression models, we estimated odds ratios (ORs) and 95% confidence intervals (CIs) for major congenital malformations during the first year of life in children with and without prenatal exposure to ASMs adjusted for potential confounders.

RESULTS

Among the 895 507 children (males, 51.3%), 31 790 (3.6%) were diagnosed with a major congenital malformation in the first year of life. In the analyses including children born in 1997, the risk of major congenital malformations among children prenatally exposed to valproate compared with children not exposed to ASMs was increased by a fully adjusted OR (aOR) of 3.95 (95% CI = 1.65-9.47). With the addition of data from the following years, the teratogenic effect of valproate was further substantiated, as the precision of the estimate improved (1997-2014: aOR = 2.44, 95% CI = 1.80-3.30).

SIGNIFICANCE

Using Danish health care data, we were able to identify a teratogenic risk associated with prenatal valproate exposure in children born in 1997, which is much earlier than prospective clinical cohorts. Health registry data represent an important tool for early identification of risk associated with drugs in pregnancy.

Management of cluster headache and other trigeminal autonomic cephalalgias in pregnancy and breastfeeding

Many clinicians lack experience in managing trigeminal autonomic cephalalgias (TACs) in pregnancy and lactation. In addition to cluster headache, TACs include hemicrania continua, paroxysmal hemicrania, and short-lasting unilateral neuralgiform headache with conjunctival injection and tearing/autonomic symptoms (SUNCT/SUNA). Treating these rare, severe headache conditions often requires off-label drugs that have uncertain teratogenic potential. In the last few years, several new treatment options and safety documentation have emerged, but clinical guidelines are lacking. This narrative review aimed to provide an updated clinical guide and good clinical practice recommendations for the management of these debilitating headache disorders in pregnancy and lactation.

Perinatal Depression and Anxiety in Women With Multiple Sclerosis: A Population-Based Cohort Study

Objective

To assess the occurrence of perinatal depression and anxiety in women before and after diagnosis of multiple sclerosis (MS).

Methods

A total of 114,629 pregnant women were included in the Norwegian Mother, Father and Child Cohort study (1999–2008). We assessed depression and anxiety by questionnaires during and after pregnancy. Women with MS were identified from national health registries and hospital records and grouped into (1) MS diagnosed before pregnancy (n = 140) or MS diagnosed after pregnancy with (2) symptom onset before pregnancy (n = 98) or (3) symptom onset after pregnancy (n = 308). Thirty-five women were diagnosed with MS in the postpartum period. The reference group (n = 111,627) consisted of women without MS.

Results

Women with MS diagnosed before pregnancy had an adjusted odds ratio of 2.0 (95% confidence interval, 1.2–3.1) for depression in the third trimester. Risk factors were adverse socioeconomic factors and history of psychiatric disease and physical/sexual abuse. The risk of anxiety was not increased. Women diagnosed with MS in the postpartum period had especially high risk of postpartum depression. Women with MS symptom onset within 5 years after pregnancy had increased risk of both depression and anxiety during pregnancy, whereas women with more than 5 years until symptom onset did not.

Conclusion

Women diagnosed with MS have increased risk of perinatal depression. Women with MS symptom onset within 5 years after pregnancy have increased risk of both depression and anxiety during pregnancy.

Quantitative EEG Power and Asymmetry Increase 36 h Before a Migraine Attack

The aim was to estimate ictal, pre- and postictal brain function changes in migraine in a blinded paired quantitative EEG (QEEG) study. EEG recordings ( n = 119) from 40 migraineurs were retrospectively classified as ictal, interictal, preictal or postictal. δ, θ, α and β power, and hemispheric asymmetry in frontocentral, temporal and occipitoparietal regions were calculated from artefact-free EEG. Power and power asymmetry were calculated for two time-windows, 36 and 72 h before/after the attack, and compared with the interictal values. Frontocentral δ power increased ( P = 0.03), whereas frontocentral θ and α power tended to increase ( P < 0.09) within 36 h before the next attack compared with the interictal period. Occipitoparietal (α and θ) and temporal (α) power were more asymmetric before the attack compared with the interictal baseline ( P < 0.04). Ictal posterior a power increased slightly ( P = 0.01). Postictal power and power asymmetry were not significantly different from interictal baseline. EEG activity seems to change shortly before the attack. This suggests that migraineurs are most susceptible to attack when anterior QEEG δ power and posterior α and θ asymmetry values are high. Changed activity patterns in cholinergic brainstem or basal forebrain nuclei and thalamo-cortical connections before the migraine attack are hypothesized.