Stress hormones and posttraumatic stress symptoms following paediatric critical illness: an exploratory study

Post-traumatic stress disorder in children after discharge from the pediatric intensive care unit: a scoping review

As the prevalence of post-traumatic stress disorder (PTSD) among children discharged from pediatric intensive care unit (PICU) continues to rise, corresponding research efforts have also increased. This scoping review aimed to review the PTSD prevalence, influencing factors, and tools used for PTSD measurements in children discharged from the PICU. This review employed the five-stage framework proposed by Arksey and O'Malley. The data sources included PubMed, Web of Science, Ovid, ScienceDirect, Springer, Scopus, CNKI, and WANFANG. Studies in English or Chinese published up to September 2023 were eligible for inclusion. The search yielded a total of 3536 results, with 31 articles meeting the inclusion criteria. The included studies reported that the prevalence of PTSD ranged from a minimum of 13% to a maximum of 84.6%. Risk factors for PTSD included medical interventions, child-related factors, and family environment. A total of 17 assessment tools for PTSD in PICU patients were reported. Given the significance of PTSD in this pediatric population, further attention, research, and intervention are warranted to help alleviate the burden of PTSD.

Prehospitalization Trauma and Physiologic Factors Associated with the Presence of Post-traumatic Stress 3 Months After PICU Discharge

BACKGROUND

Children admitted to the pediatric intensive care unit (PICU) have post-traumatic stress (PTS) rates up to 64%, and up to 28% of them meet criteria for PTS disorder (PTSD). We aim to examine whether a prior trauma history and increased physiologic parameters due to a heightened sympathetic response are associated with later PTS. Our hypothesis was children with history of prehospitalization trauma, higher heart rates, blood pressures, cortisol, and extrinsic catecholamine administration during PICU admission are more likely to have PTS after discharge.

METHODS

This is a prospective, observational study of children admitted to the PICU at an urban, quaternary, academic children's hospital. Children aged 8 to 17 years old without developmental delay, severe psychiatric disorder, or traumatic brain injury were included. Children's prehospitalization trauma history was assessed with a semistructured interview. All in-hospital variables were from the electronic medical record. PTS was present if children had 4 of the Diagnostic and Statistical Manual of Mental Disorders IV criteria for PTSD. Student's t- and chi-squared tests were used to compare the presence or absence of prior trauma and all of the PICU-associated variables.

RESULTS

Of the 110 children at baseline, 67 had 3-month follow-up. In the latter group, 46% met the criteria for PTS, mean age of 13 years (SD 3), 57% male, a mean PRISM III score of 4.9 (SD 4.3), and intensive care unit length of stay 6.5 days (SD 7.8). There were no statistically significant differences in the demographics of the children with and without PTS. The only variable to show significance was trauma history; children with prehospitalization trauma were more likely to have PTS at 3-month follow-up (P = .02).

CONCLUSIONS

Prehospitalization trauma history was associated with the presence of PTS after admission to the PICU. This study suggests future studies should shift to the potential predictive benefit of screening children for trauma history upon PICU admission.

Risk factors of post-traumatic stress disorder after hospitalization in a pediatric intensive care unit: a systematic literature review

The number of studies on post-traumatic stress disorder after hospitalization in a pediatric intensive care unit raised since 2004. The objective of this systematic review was to summarize and critically examine the literature about risk factors for these children to develop post-traumatic stress disorder following admission to an intensive care unit. The data sources were PubMed, Cochrane, Web of Science, PsycInfo, SUDOC, Scopus, and ScienceDirect. Studies were selected if they were in English or French and published between 01/01/2004 and 31/01/2022. Studies were excluded if patients were less than 1 month old and if no post-traumatic stress disorder was found. The internal validity and risk of bias were assessed using the National Institutes of Health Study Quality Assessment Tools for observational studies and the Ottawa Scale was used for the interventional study. The search yielded 523 results and 22 articles met inclusion criteria. Three common risk factors were identified from the data: parental post-traumatic stress disorder (especially in mothers), severity of illness and delusional memories. Internalizing behavior in children, acute parent and child stress, emergency admission and sepsis are also potential risk factors that require further investigation. The prevalence of this pathology is substantial (between 14 and 36%) and increasing awareness among pediatricians and psychologists seems necessary. Prevention programs are being studied to reduce the incidence of post-traumatic stress disorder in this population. Child and adolescent psychiatry liaison should collaborate with pediatric teams to support this objective.

The Impact of Service Dogs on Military Veterans and (Ex) First Aid Responders With Post-traumatic Stress Disorder

Due to its novelty and lack of empirical study it remains unclear if a service dog truly mitigates the burden of post-traumatic stress disorder (PTSD) symptoms. To cross sectionally investigate the effect of service dogs on veterans and first aid responders with PTSD, we studied subjective and physiological parameters in 65 individuals divided over four groups. These groups were: veterans and first aid responders with PTSD and a service dog (n = 20), with PTSD and a companion dog (n = 10), with PTSD without a dog (n = 12) and a group without PTSD (n = 23). We found that veterans and first aid responders with PTSD who had a service dog showed significantly less PTSD related symptoms, better sleep quality, and better wellbeing experience, than those with a companion dog. Those with a service dog additionally experienced fewer PTSD related symptoms than those without a service dog and tended to walk more than individuals without PTSD. No differences were found in cortisol levels between groups though and changes in both salivary cortisol and activity were not linked to improved welfare experience. Though the use of physiological measurement methods thus warrants more research, our study indicates that the subjective experience of wellbeing, sleep quality and PTSD related symptoms is improved by the presence of a service dog.

Persisting neuroendocrine abnormalities and their association with physical impairment 5 years after critical illness

Background

Critical illness is hallmarked by neuroendocrine alterations throughout ICU stay. We investigated whether the neuroendocrine axes recover after ICU discharge and whether any residual abnormalities associate with physical functional impairments assessed 5 years after critical illness.

Methods

In this preplanned secondary analysis of the EPaNIC randomized controlled trial, we compared serum concentrations of hormones and binding proteins of the thyroid axis, the somatotropic axis and the adrenal axis in 436 adult patients who participated in the prospective 5-year clinical follow-up and who provided a blood sample with those in 50 demographically matched controls. We investigated independent associations between any long-term hormonal abnormalities and physical functional impairments (handgrip strength, 6-min walk distance, and physical health-related quality-of-life) with use of multivariable linear regression analyses.

Results

At 5-year follow-up, patients and controls had comparable serum concentrations of thyroid-stimulating hormone, thyroxine (T₄), triiodothyronine (T₃) and thyroxine-binding globulin, whereas patients had higher reverse T₃ (rT₃, p = 0.0002) and lower T₃/rT₃ (p = 0.0012) than controls. Patients had comparable concentrations of growth hormone, insulin-like growth factor-I (IGF-I) and IGF-binding protein 1 (IGFBP1), but higher IGFBP3 (p = 0.030) than controls. Total and free cortisol, cortisol-binding globulin and albumin concentrations were comparable for patients and controls. A lower T₃/rT₃ was independently associated with lower handgrip strength and shorter 6-min walk distance (p ≤ 0.036), and a higher IGFBP3 was independently associated with higher handgrip strength (p = 0.031).

Conclusions

Five years after ICU admission, most hormones and binding proteins of the thyroid, somatotropic and adrenal axes had recovered. The residual long-term abnormality within the thyroid axis was identified as risk factor for long-term physical impairment, whereas that within the somatotropic axis may be a compensatory protective response. Whether targeting of the residual abnormality in the thyroid axis may improve long-term physical outcome of the patients remains to be investigated.

Trial registration ClinicalTrials.gov: NCT00512122, registered on July 31, 2007 (https://www.clinicaltrials.gov/ct2/show/NCT00512122).

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-021-03858-1.

Glucocorticoids and the Brain after Critical Illness

Treatment for critical illness typically focuses on a patient's short-term physical recovery; however, recent work has broadened our understanding of the long-term implications of illness and treatment strategies. In particular, survivors of critical illness have significantly elevated risk of developing lasting cognitive impairment and psychiatric disorders. In this review, we examine the role of endogenous and exogenous glucocorticoids in neuropsychiatric outcomes following critical illness. Illness is marked by acute elevation of free cortisol and adrenocorticotropic hormone suppression, which typically normalize after recovery; however, prolonged dysregulation can sometimes occur. High glucocorticoid levels can cause lasting alterations to the plasticity and structural integrity of the hippocampus and prefrontal cortex, and this mechanism may plausibly contribute to impaired memory and cognition in critical illness survivors, though specific evidence is lacking. Glucocorticoids may also exacerbate inflammation-associated neural damage. Conversely, current evidence indicates that glucocorticoids during illness may protect against the development of post-traumatic stress disorder. We propose future directions for research in this field, including determining the role of persistent glucocorticoid elevations after illness in neuropsychiatric outcomes, the role of systemic vs neuroinflammation, and probing unexplored lines of investigation on the role of mineralocorticoid receptors and the gut-brain axis. Progress toward personalized medicine in this area has the potential to produce tangible improvements to the lives patients after a critical illness, including Coronavirus Disease 2019.

Outcomes following admission to paediatric intensive care: A systematic review

AIM

To describe the long-term health outcomes of children admitted to a paediatric intensive care unit.

METHODS

A systematic review of the literature was performed. Studies of children under 18 years of age admitted to a paediatric intensive care unit were included. Studies focussed on neonatal admissions and investigating specific paediatric intensive care unit interventions or admission diagnoses were excluded. A table was created summarising the study characteristics and main findings. Risk of bias was assessed using the Newcastle Ottawa Quality Assessment Scale for observational studies. Primary outcome was short-, medium- and long-term mortality. Secondary outcomes included measures of neurodevelopment, cognition, physical, behavioural and psychosocial function as well as quality of life.

RESULTS

One hundred and eleven studies were included, most were conducted in high-income countries and focussed on short-term outcomes. Mortality during admission ranged from 1.3 to 50%. Mortality in high-income countries reduced over time but this trend was not evident for lower income countries. Higher income countries had lower standardised mortality rates than lower income countries. Children had an ongoing increased risk of death for up to 10 years following intensive care admission as well as increased physical and psychosocial morbidity compared to healthy controls, with associated poorer quality of life.

CONCLUSIONS

There is limited high-level evidence for the long-term health outcomes of children after intensive care admission, with the burden of related morbidity remaining greater in poorly resourced regions. Further research is recommended to identify risk factors and modifiable factors for poor outcomes, which could be targeted in practice improvement initiatives.

Inflammation and psychopathology in children following PICU admission: an exploratory study

Background

Survivors of critical illness in childhood commonly display subsequent psychiatric symptoms including emotional and behavioural difficulties, and manifestations of post-traumatic stress disorder (PTSD). Anomalies in inflammatory profiles are an established finding in these childhood psychiatric conditions.

Objective

This exploratory study aimed to investigate whether abnormal peripheral blood inflammatory markers measured during paediatric intensive care unit (PICU) admission were associated with psychiatric symptoms after discharge.

Methods

We performed a prospective observational cohort study on 71 children with septic illness, meningoencephalitis and other critical disorders admitted to two PICUs between 2007 and 2010. 3–6 months following discharge, subjects were assessed for global psychiatric risk (ie, presence of emotional and behavioural difficulties on the parental Strengths and Difficulties Questionnaire (SDQ)), and for PTSD risk using the child-rated Impact of Events Scale (IES-8). Inflammatory and related biological markers were transcribed from PICU admission notes (white cell count, lymphocytes, neutrophils, C reactive protein (CRP), platelets, fibrinogen and lactate).

Findings

Global psychiatric risk at follow-up was associated with abnormal lymphocyte count during admission (χ²=6.757, p=0.014, n=48). In children with sepsis, partial correlation analyses controlling for age and gender highlighted associations between (i) SDQ scores and low lymphocyte count (r=−0.712; p=0.009, n=14), and (ii) IES-8 score and high CRP levels (r=0.823; p=0.006, n=11). These associations remained after correction for multiple comparisons.

Conclusion

These results support the hypothesis that acute inflammation may play a role in determining the development of psychopathology following PICU admission.

Clinical implications

If the findings are replicated, they may help to better highlight which children are at risk of post-PICU psychopathology and appropriately target follow-up.

Post-traumatic stress after PICU and corticosteroid use

AIM

To examine the association between corticosteroid use in paediatric intensive care units (PICU) and subsequent symptoms of post-traumatic stress disorder (PTSD).

METHODS

The subjects were children aged 8-16 years admitted to PICU with sepsis, meningoencephalitis (ME) and other disorders. Illness information was extracted from case notes; 3-6 months post discharge children completed a PTSD symptom questionnaire (eight-item Impact of Events Scale (IES-8)) assessing intrusion and avoidance symptoms. Saliva samples were also collected for cortisol profile analysis.

RESULTS

53 children completed the IES-8 questionnaires. 33 provided saliva samples. 19 (36%) received corticosteroids. In children with sepsis (n=15), corticosteroid use was associated with significantly lower PTSD intrusion symptom scores. There was a trend towards an association between corticosteroid use and lower evening cortisol levels. There was a comparable but weaker trend in children with ME.

DISCUSSION

Corticosteroid use may be associated with fewer PTSD symptoms and lower evening cortisol levels following PICU admission in children with sepsis.

Hair cortisol in relation to acute and post-traumatic stress symptoms in children and adolescents

BACKGROUND

We report on the preliminary results of two independent studies that (1) compare the hair cortisol concentrations (HCC) of healthy controls with patients displaying post-traumatic stress symptoms (PTSS, study 1+2), (2) investigate whether pre-trauma HCC are predictive for the development of acute stress symptoms (ASS) and PTSS (study 1) and (3) determine whether HCC correlate with PTSS in a clinical sample of children (study 2).

METHODS

In study 1, the clinical symptoms of 35 minors were examined one (T1) and seven weeks (T2) after surgery following an accident. Hair samples were taken after the accident that reflect cortisol secretion over the past three months before the accident (healthy controls). In study 2, HCC and PTSS symptoms were cross-sectionally assessed in 22 minors who had experienced a psychological trauma.

RESULTS

The HCC of patients with PTSS were lower than the HCC of healthy controls (study 1+2). Secondary analyses showed that HCC were significantly lower in male PTSS patients than in male healthy controls, whereas the HCC in females were comparably low in both groups. Pre-trauma HCC did not predict the total ASS and PTSS scores (study 1) and HCC were not directly related to the total PTSS scores (study 2).