The role of general anesthesia on traits of neurodevelopmental disorders in a Swedish cohort of twins

Pediatric Anesthesia Exposure: Decoding Its Neurodevelopmental Implications and Navigating the Nuances

General anesthesia is fundamental in pediatric medical interventions, but its potential neurodevelopmental impact on children has raised concerns, necessitating a thorough investigation. This systematic review aimed to assess the association between pediatric anesthesia exposure and neurodevelopmental outcomes, focusing on dosage effects and identifying high-risk groups. The study involved an extensive literature search across PubMed, Medline, and Google Scholar, selecting 40 relevant studies from an initial pool of 2,000, based on inclusion criteria that focused on children under 18 years exposed to anesthesia, excluding those with major comorbidities or perioperative physiological insults. It was observed that while a single exposure to anesthesia had minimal impact on general neurodevelopment, repeated or prolonged exposures posed greater concerns. Despite these findings, the study identified gaps in certain areas like adaptive behavior and sensory cognition due to limited data. The conclusion drawn is that although the evidence on anesthesia-induced neurotoxicity in children remains inconclusive, the implications of pediatric anesthesia exposure are significant enough to warrant careful consideration by healthcare professionals, who should balance the procedural benefits against the risks. This study also calls for future research to standardize methodologies and employ consistent, validated neurodevelopmental measurement tools.

Effect of cesarean section on the risk of autism spectrum disorders/attention deficit hyperactivity disorder in offspring: a meta-analysis

PURPOSE

This study was conducted to investigate the relationship between cesarean section (CS) offspring and autism spectrum disorders (ASD)/attention deficit hyperactivity disorder (ADHD).

METHODS

Searching of the databases (PubMed, Web of Science, Embase, and Cochrane Library) for studies on the relationship between mode of delivery and ASD/ADHD until August 2022. The primary outcome was the incidence of ASD/ADHD in the offspring.

RESULTS

This meta-analysis included 35 studies (12 cohort studies and 23 case-control studies). Statistical results showed a higher risk of ASD (odds ratio (OR) = 1.25, P < 0.001) and ADHD (OR = 1.11, P < 0.001) in CS offspring compared to the VD group. Partial subgroup analysis showed no difference in ASD risk between CS and VD offspring in sibling-matched groups (OR = 0.98, P = 0.625). The risk of ASD was higher in females (OR = 1.66, P = 0.003) than in males (OR = 1.17, P = 0.004) in the CS offspring compared with the VD group. There was no difference in the risk of ASD between CS under regional anesthesia group and VD group (OR = 1.07, P = 0.173). However, the risk of ASD was higher in the CS offspring under general anesthesia than in the VD offspring (OR = 1.62, P < 0.001). CS offspring developed autism (OR = 1.38, P = 0.011) and pervasive developmental disorder-not otherwise specified (OR = 1.46, P = 0.004) had a higher risk than VD offspring, but there was no difference in Asperger syndrome (OR = 1.19, P = 0.115). Offspring born via CS had a higher incidence of ADHD in different subgroup analyses (sibling-matched, type of CS, and study design).

CONCLUSIONS

In this meta-analysis, CS was a risk factor for ASD/ADHD in offspring compared with VD.

Risk of attention deficit hyperactivity disorder diagnosis following multiple exposures to general anesthesia in the paediatric population: A systematic review and meta-analysis

Objectives

The risk of attention deficit hyperactivity disorder (ADHD) following multiple exposures to anesthesia has been debated. Our objective was to systematically review the literature to examine the association between multiple exposures to general anesthesia before age 5 and subsequent diagnosis of ADHD.

Methods

A systematic search of EMBASE, PubMed, and SCOPUS was performed using key search terms in February 2022. We included studies that: were published after 1980, included only otherwise healthy children who experienced two or more exposures to general anesthetic before age 5, diagnosed ADHD by a medical professional before age 19 years after exposure to general anesthetic, were cross-sectional, case-control, or cohort study, and were published in English. The results (expressed as hazard ratios [HR] and associated 95% confidence intervals [CI]) were pooled using meta-analytic techniques. Studies which did not present their results as HR and 95% CI were analyzed separately. GRADE was used to determine the certainty of the findings. PRISMA guidelines were followed at each stage of the review.

Results

Eight studies (196,749 children) were included. Five reported HR and 95% CI and were subsequently pooled for meta-analysis. Multiple exposures to anesthesia were associated with diagnosis of ADHD before the 19th year of life (HR: 1.71; 95% CI: 1.59, 1.84). Two of the three studies not used in the meta-analysis also found an increased risk of ADHD diagnosis following multiple anesthetic exposures.

Conclusions

There was an association between multiple early exposures to general anesthesia and later diagnosis of ADHD.

General anesthesia in early childhood and possible association with autism: a population-based matched cohort study

BACKGROUND

In experimental animal studies, exposure to general anesthesia in early childhood may results in changes in infant brain morphology and behavior, potentially leading to the development of autistic behaviors in the long-term. However, in clinical studies the role of exposure to general anesthesia in early childhood and the risk of autism is unknown.

METHODS

This is a population-based cohort study including all children aged 0-5 years of age exposed to general anesthesia between 2001 and 2014 and a corresponding matched population without such an exposure. Propensity score calculation was based on 49 variables (including age of parents, malformations, APGAR Score, and family income, among others). Quasi-Poisson regression was used to estimate risk ratios (RRs) with 95% confidence intervals (CIs) for the association between exposure to general anesthesia and autism or autism spectrum disorder.

RESULTS

In total, 401,750 children exposed to general anesthesia were compared with 1,187,796 unexposed individuals. Autism or autism spectrum disorder were more common in the children exposed to general anesthesia as compared to unexposed children (1.65% and 0.98%, respectively, P<0.01). There was a statistically significant higher risk of autism or autism spectrum disorder in children exposed to general anesthesia as compared to unexposed children also after propensity score adjustment (RR 1.62, 95% CI: 1.57-1.67).

CONCLUSIONS

Exposure to general anesthesia in early childhood was associated with an increased risk of autism or autism spectrum disorder. Future studies are needed to asses if general anesthesia may cause autism or if the association is due to other factors.

Anesthetic Exposure During Childhood and Neurodevelopmental Outcomes: A Systematic Review and Meta-analysis

IMPORTANCE

Clinical studies of neurodevelopmental outcomes after anesthetic exposure have evaluated a range of outcomes with mixed results.

OBJECTIVE

To examine via meta-analyses the associations between exposure to general anesthesia and domain-specific neurodevelopmental outcomes in children.

DATA SOURCES

PubMed/MEDLINE, Embase, CINAHL, Web of Science and the Cochrane Library were searched from inception to August 31, 2021.

STUDY SELECTION

Inclusion criteria were exposures to procedures requiring general anesthesia at younger than 18 years and evaluation of long-term neurodevelopmental function after exposure. Studies lacking unexposed controls or focused on children with major underlying comorbidities were excluded.

DATA EXTRACTION AND SYNTHESIS

Extracted variables included effect size; hazard, risk, or odds ratio; number of exposures; procedure type; major comorbidities; age of exposure and assessment; presence of unexposed controls; and study design. Studies were independently reviewed by 2 coders, and review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Data were pooled using a random-effects model.

MAIN OUTCOMES AND MEASURES

The main outcomes were standardized mean differences (SMD) for scores in the neurodevelopmental domains of academics, behavioral problems, cognition, executive function, general development, language, motor function, nonverbal reasoning, social cognition, and hazard and risk of neurodevelopmental disorder diagnoses.

RESULTS

A total of 31 studies contributed data for meta-analysis. For each of the assessed neurodevelopmental domains, the numbers of children evaluated ranged from 571 to 63 315 exposed and 802 to 311 610 unexposed. Children with any exposure (single or multiple) had significantly worse behavioral problems scores, indicating more behavioral problems (SMD, -0.10; 95% CI, -0.18 to -0.02; P = .02), and worse scores in academics (SMD, -0.07; 95% CI -0.12 to -0.01; P = .02), cognition (SMD, -0.03; 95% CI, -0.05 to 0.00; P = .03), executive function (SMD, -0.20; 95% CI, -0.32 to -0.09; P < .001), general development (SMD, -0.08; 95% CI, -0.13 to -0.02; P = .01), language (SMD, -0.08; 95% CI, -0.14 to -0.02; P = .01), motor function (SMD, -0.11; 95% CI, -0.21 to -0.02; P = .02), and nonverbal reasoning (SMD, -0.15; 95% CI, -0.27 to -0.02; P = .02). Higher incidences of neurodevelopmental disorder diagnoses were also reported (hazard ratio, 1.19; 95% CI, 1.09 to 1.30; P < .001; risk ratio, 1.81; 95% CI, 1.25 to 2.61; P = .002).

CONCLUSIONS AND RELEVANCE

These findings support the hypothesis that associations between anesthetic exposure during childhood and subsequent neurodevelopmental deficits differ based on neurodevelopmental domain.

A Critical Review of Statistical Methods for Twin Studies Relating Exposure to Early Life Health Conditions

When investigating disease etiology, twin data provide a unique opportunity to control for confounding and disentangling the role of the human genome and exposome. However, using appropriate statistical methods is fundamental for exploiting such potential. We aimed to critically review the statistical approaches used in twin studies relating exposure to early life health conditions. We searched PubMed, Scopus, Web of Science, and Embase (2011–2021). We identified 32 studies and nine classes of methods. Five were conditional approaches (within-pair analyses): additive-common-erratic (ACE) models (11 studies), generalized linear mixed models (GLMMs, five studies), generalized linear models (GLMs) with fixed pair effects (four studies), within-pair difference analyses (three studies), and paired-sample tests (two studies). Four were marginal approaches (unpaired analyses): generalized estimating equations (GEE) models (five studies), GLMs with cluster-robust standard errors (six studies), GLMs (one study), and independent-sample tests (one study). ACE models are suitable for assessing heritability but require adaptations for binary outcomes and repeated measurements. Conditional models can adjust by design for shared confounders, and GLMMs are suitable for repeated measurements. Marginal models may lead to invalid inference. By highlighting the strengths and limitations of commonly applied statistical methods, this review may be helpful for researchers using twin designs.

A National Population Cohort Study Showed That Exposure to General Anesthesia in Early Childhood Is Associated with an Increase in the Risk of Developmental Delay

This study investigated the relationship between exposure to general anesthesia (GA) and the risk of cognitive and mental disorders. This study has thus investigated the relationships between exposure to GA before the age of 3 and subsequent cognitive and mental disorders in a national-wide research sample. We obtained our subjects from the National Health Insurance Research Database (NHIRD) of Taiwan, which was based on the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM). Children in the hospital aged less than 3 years old were included if there was GA exposure or not during the period of year 1997 to 2008. Cox proportional hazard regression models adjusted for potential confounding factors were used to estimate the relative magnitude of the risk associated with GA exposure. The cohort contained 2261 subjects with GA and 4522 children without GA as a comparison group. GA exposure group had a higher rate of developmental delay than in the without GA group (hazard ratio 1.46, p < 0.0001). There was no significant difference in the overall incidence of ADHD, autism and intellectual disability between the GA-exposed group and the comparison cohort. In conclusion, this study reported that children exposed to GA early before the age of three had a small association with increased risk of development delay thereafter.

Anesthesia, sex and miscarriage history may influence the association between cesarean delivery and autism spectrum disorder

BACKGROUND

To explore the association between cesarean section (CS) and risk of autism spectrum disorder (ASD), and evaluate the possible factors influencing this association.

METHODS

In total, 950 patients diagnosed with ASD and 764 healthy controls were recruited in this study. Socio-demographic characteristics and prenatal, perinatal, and neonatal characteristics were compared between the two groups. Univariate and multivariable conditional logistic regression analyses were applied to adjust for confounders. Further stratified analyses based on sex and miscarriage history were similarly performed to explore the factors influencing the association between CS and ASD.

RESULTS

CS was evidently associated with an elevated risk of ASD (adjusted odds ratio [aOR] = 1.606, 95% confidence interval (CI) = 1.311-1.969). Unlike regional anesthesia (RA), only CS performed under general anesthesia (GA) consistently elevated the risk of ASD (aOR = 1.887, 95% CI = 1.273-2.798) in females and males in further stratified analysis. The risk of children suffering from ASD following emergency CS was apparently increased in males (aOR = 2.390, 95% CI = 1.392-5.207), whereas a higher risk of ASD was observed among voluntary CS and indicated CS subgroups (aOR = 2.167, 95% CI = 1.094-4.291; aOR = 2.919, 95% CI = 1.789-4.765, respectively) in females. Moreover, the interaction term of CS and past miscarriage history (β = - 0.68, Wald χ2 = 7.5, df = 1, p = 0.006)) was similarly defined as influencing ASD.

CONCLUSIONS

The exposure of children to GA during CS may explain the possible/emerging association between CS and ASD. In addition, sex and miscarriage history could equally be factors influencing the association between CS and ASD.

Does Exposure to General Anesthesia Increase Risk of ADHD for Children Before Age of Three?

Objective: The objective of the study was to evaluate the relationship between frequency of exposure to general anesthesia before the age of 3 and subsequent risk of diagnosis for attention-deficit hyperactivity disorder (ADHD). Method: We searched PubMed, Embase, Web of Science, and Cochrane Library database for eligible inclusion in the meta-analysis. The indicated outcomes were extracted from the included studies, and the combined effects were calculated using the RevMan software 5.3. Results: Compared with no exposure to general anesthesia, single exposure to general anesthesia did not increase the risk of ADHD for children before the age of 3 [hazard ratio (HR): 1.14, 95%; confidence intervals (CI): 0.97-1.35; p = 0.11; I ² = 0%], while multiple exposures to general anesthesia did increase the risk of ADHD (HR: 1.83; 95% CIs: 1.00-3.32; p = 0.05; I ² = 81%). Conclusion: Multiple, but not single, exposures to general anesthesia in children before age of 3 increased the risk of ADHD.

Neonatal sevoflurane exposure induces impulsive behavioral deficit through disrupting excitatory neurons in the medial prefrontal cortex in mice

Sevoflurane, in particular multiple exposures, has been reported to cause the abnormal neurological development including attention-deficit/hyperactivity disorder (ADHD). This study is to investigate ADHD-like impulsivity in adult mice after repeated sevoflurane exposures at the neonatal stage. Six-day-old pups were exposed to 60% oxygen in the presence or absence of 3% sevoflurane for 2 h and the treatment was administrated once daily for three consecutive days. To assess the impulsivity, the cliff avoidance reaction (CAR) was carried out at the 8th week. Our results showed that repeated sevoflurane treatment increased the number of jumps and shortened the jumping latency in the CAR test. The cortices were harvested for immunostaining to detect c-Fos and calmodulin-dependent protein kinase IIα (CaMKIIα) expression in the medial prefrontal cortex (mPFC). We found that mPFC neurons, especially excitatory neurons, were highly activated and related to impulsive behavior. The activation viruses (AAV-CaMKIIα-hM3Dq) were injected to evaluate the effects of specific activation of mPFC excitatory neurons on impulsive behavior in the presence of clozapine-N-oxide (CNO). Likewise, the inhibitory viruses (AAV-CaMKIIα-hM4Di) were injected in the sevoflurane group to explore whether the mPFC excitatory neuronal inhibition reduced the impulsivity. Our results revealed that chemogenetic activation of mPFC excitatory neurons induced impulsive behavior whereas inhibition of mPFC excitatory neurons partially rescued the deficit. These results indicate that repeated sevoflurane exposures at the critical time induce impulsive behavior accompanied with overactivation of mPFC excitatory neurons in adult stages. This work may further extend to understand the ADHD-like impulsive behavior of the anesthetic neurotoxicity.

Risk of Attention Deficit Hyper Activity Disorder After Early Exposure to General Anesthesia; A Case Control Study

Background: Over the past decade, following the discovery that developing brain of immature animals was affected by anesthetic agents, the safety of general anesthesia (GA) in early life has been questioned. Objectives: We investigated the association between anesthesia exposure in children and ADHD development. Methods: This case-control study was conducted at pediatric psychology clinic of our institution and a pediatric neurology private clinic during 2019. Firstly the responsible resident of anesthesiology separated new ADHD cases. Then a questionnaire was filled out through an almost 10 minute’s telephone interview. Finally, frequency distribution of GA was compared between ADHD cases and controls. Results: Finally, the data from 210 children were analyzed. Among 105 ADHD cases, 19% had a history of a procedure requiring GA while it was 3.8% in control group. Comparing the two groups a significant difference was observed regarding the age of receiving GA (P = 0.004), gender (P < 0.001), the history of receiving GA (P = 0.001) and the number of anesthesia exposures (P = 0.001). According to logistic regression analysis, male gender (P = 0.001) OR 3.11 (95CI = 1.63 - 5.93) and age (P = 0.003) OR 0.92 (95CI = 0.87 - 0.97) were significant predictors of early exposure to GA and ADHD development. Conclusions: It was revealed that early exposure to GA might be a risk factor for later developing ADHD. Boys might be more sensitive to the long term adverse effects of anesthetic agents than girls. Further prospective well-planned studies are needed to confirm these findings.

Attention difficulties and physical dysfunction common in children with complex congenital malformations: a study of preschool children with VACTERL association

Aim

Knowledge on the neurodevelopmental and physical function in children with vertebral defects, anorectal malformations, cardiac defects, tracheo‐oesophageal fistula, renal and limb malformations (VACTERL) is scarce. We evaluated Swedish preschool children with VACTERL and identified whether they would need extra support in school.

Methods

From 2015 to 2017, we recruited children aged 5–7 with VACTERL association from the paediatric surgical centre at the University Children's Hospital at Uppsala. Neurodevelopmental function was assessed by age‐appropriate intelligence and visual and auditory attention tests, and the children's behaviour and attention were observed by an experienced psychologist. Physical function was evaluated through parental interviews and examinations. Data on patient characteristics, including any surgery and anaesthesia, were extracted from medical records.

Results

Of the 13 eligible families, 10 agreed to participate. Intelligence was within the normal range for all children, but attention difficulties were found in eight of the children, requiring adjustments at school, and two of these were later diagnosed with attention deficit hyperactivity disorder. All children had physical dysfunctions that affected their daily nutrition, bowel or bladder functions.

Conclusion

Attention difficulties and physical dysfunction were common in Swedish preschool children aged 5–7 with VACTERL and they would need support and adjustments when they started school.

General Anesthesia-Related Neurotoxicity in the Developing Brain and Current Knowledge and Practice of Physicians at Guilan Academic Hospitals

Background

Recent articles about the topic of the anesthetic agents-related neurotoxicity have currently attracted the attention to the issue in the anesthesiology community. However, specialists in other fields should also be aware of this potential risk.

Objectives

This study aimed to evaluate the knowledge and practice of physicians at Guilan academic hospitals regarding general anesthesia-related neurotoxicity.

Methods

Firstly, the responsible anesthesia resident explained the purpose of this work to Guilan faculty and residents and if they agreed to participate a questionnaire containing 12 items was filled via a face to face interview.

Results

A response rate of 100% was achieved (271 responders from 271 eligible study responders). Also, 89 (33.1%) responders were attending, 180 (66.9%) were residents, 112 (41.6%) were female, and 157 (58.4%) were male. The mean years of experience was 8.8 ± 4.82 (2 - 28 years). According to the achieved data, the majority of the precipitants did not believe in GA toxicity.

Conclusions

This paper revealed that the current curriculum does not sufficiently address the anesthesia-related neurotoxicity problem. Indeed, the need for training and communication with non-anesthesia medical colleagues was highlighted.

Montelukast and Nasal Corticosteroids to Treat Pediatric Obstructive Sleep Apnea: A Systematic Review and Meta-analysis

Objective

To systematically review the literature on anti-inflammatory medications for treating pediatric obstructive sleep apnea and perform meta-analysis of the available data.

Data Sources

PubMed/MEDLINE and 4 additional databases.

Review Methods

Three authors independently and systematically searched through June 28, 2018, for studies that assessed anti-inflammatory therapy for treatment of pediatric obstructive sleep apnea (OSA). Data were compiled and analyzed using Review Manager 5.3 (Nordic Cochrane Centre).

Results

After screening 135 studies, 32 were selected for review with 6 meeting inclusion criteria. In total, 668 patients aged 2 to 5 years met inclusion criteria for meta-analysis. Of these, 5 studies (166 children) that evaluated montelukast alone as treatment for pediatric OSA found a 55% improvement in the apnea-hypopnea index (AHI) (mean [SD] 6.2 [3.1] events/h pretreatment and 2.8 [2.7] events/h posttreatment; mean difference [MD] of −2.7 events/h; 95% confidence interval [CI], –5.6 to 0.3) with improvement in lowest oxygen saturation (LSAT) from 89.5 (6.9) to 92.1 (3.6) (MD, 2.2; 95% CI, 0.5-4.0). Two studies (502 children) observing the effects of montelukast with intranasal corticosteroids on pediatric OSA found a 70% improvement in AHI (4.7 [2.1] events/h pretreatment and 1.4 [1.0] events/h posttreatment; MD of −4.2 events/h; 95% CI, –6.3 to −2.0), with an improvement in LSAT from 87.8 (3.1) to 92.6 (2.2) (MD, 4.8; 95% CI, 4.5-5.1).

Conclusions

Treatment with montelukast and intranasal steroids or montelukast alone is potentially beneficial for short-term management of mild pediatric OSA.