Childhood Inflammation Linked to Later Mental Health Risks

Summary: Children with persistent inflammation are at a higher risk of developing mental health disorders like psychosis and depression in early adulthood. A study found that elevated inflammation markers, particularly around age 9, significantly increase the risk of these disorders, as well as cardiometabolic diseases such as insulin resistance. The research suggests that early-life inflammation could be a critical factor in later mental and physical health issues, prompting the need for further investigation into its role.

Key Facts

  • Persistent childhood inflammation increases the risk of psychosis and depression.
  • Inflammation at age 9 is linked to higher risks of mental health disorders at 24.
  • Study suggests potential for early intervention and new treatment targets.

Source: University of Birmingham

Children who have persistently raised inflammation are at a higher risk of experiencing serious mental health disorders including psychosis and depression in early adulthood, according to a study published today in JAMA Psychiatry.

The research lead by the University of Birmingham also found that those who had experienced inflammation at a young age were at a higher risk of developing cardiometabolic diseases such as insulin resistance – an early form of diabetes. 

The results of the study have provided strong evidence needed to prompt further research that would seek to ascertain whether or not inflammation plays a causal role in such disorders or is merely an indicator. Credit: Neuroscience News

The study used data collected by the Avon Longitudinal Study of Parents and Children (ALSPAC) – also known as Children of the 90s – and included a total of 6,556 participants of whom 50.4% were female. Inflammation was identified by increased levels of the general inflammatory marker C-reactive protein (CRP) recorded in participants at ages 9, 15 and 17 years.

Of the two groups identified with persistently raised inflammation throughout their developing years, the researchers discovered that it was the group whose CRP levels peaked earlier in childhood, around age 9, that were most associated with subsequent higher risks of depression and psychosis at age 24.

Lead author on the study, Edward Palmer of the University of Birmingham said: “There’s growing evidence of an association between inflammation and psychotic, depressive and cardiometabolic disorders, however little has been done to explore the different trajectories of inflammation during childhood and the association between those and both mental and physical health outcomes in early adulthood.”  

“When we look longitudinally, there is really strong evidence that inflammation earlier on in childhood is a significant risk factor for developing schizophrenia, depression and insulin resistance in later life. Some of the rates of developing these disorders within the group with inflammation who peaked around age 9 were four to five times the chances for those without inflammation.”

The results of the study have provided strong evidence needed to prompt further research that would seek to ascertain whether or not inflammation plays a causal role in such disorders or is merely an indicator.

Edward Palmer added: “We’re still a way off demonstrating whether raised inflammation plays a causal role in these disorders but it is clear that the inflammation pre-dates instances of mental illness and potentially related metabolic dysfunction, and as such further research needs to be done into the mechanisms driving it. This could ultimately lead to early life risk profiling, different kinds of early intervention and possible new treatment targets.” 

About this neurodevelopment and mental health research news

Author: Tony Moran
Source: University of Birmingham
Contact: Tony Moran – University of Birmingham
Image: The image is credited to Neuroscience News

Original Research: Open access.
Trajectories of Inflammation in Youth and Risk of Mental and Cardiometabolic Disorders in Adulthood” by Edward Palmer et al. JAMA Psychiatry


Abstract

Trajectories of Inflammation in Youth and Risk of Mental and Cardiometabolic Disorders in Adulthood

Importance  

Research suggests that low-grade, nonresolving inflammation may predate adult mental and physical illness. However, evidence to date is largely cross-sectional or focuses on single disorder outcomes.

Objectives  

To examine trajectories of inflammation as measured by C-reactive protein (CRP) levels in a large sample of children and adolescents, and to explore associations between different identified trajectories and mental and related cardiometabolic health outcomes in early adulthood.

Design, Setting, and Participants  

In a longitudinal cohort study using data from the large UK-based Avon Longitudinal Study of Parents and Children (ALSPAC), latent class growth analysis (LCGA) was used to explore different trajectories of inflammation, with logistic regression exploring association with mental and physical health outcomes. Participants with measurable CRP data and associated mental and cardiometabolic health outcomes recorded were included in the analysis. Data analysis was performed from May 1, 2023, to March 30, 2024.

Exposures  

Inflammation was assessed via CRP levels at ages 9, 15, and 17 years. LCGA was used to identify different trajectories of inflammation.

Main Outcomes and Measures  

Outcomes assessed at age 24 years included psychotic disorders, depressive disorders, anxiety disorders, hypomania, and, as a measure of insulin resistance, Homeostasis Model Assessment (HOMA2) score.

Results  

A total of 6556 participants (3303 [50.4%] female) were included. Three classes of inflammation were identified: persistently low CRP levels (reference class, n = 6109); persistently raised CRP levels, peaking at age 9 years (early peak, n = 197); and persistently raised CRP levels, peaking at age 17 years (late peak, n = 250). Participants in the early peak group were associated with a higher risk of psychotic disorder (odds ratio [OR], 4.60; 95% CI, 1.81-11.70; P = .008), a higher risk of severe depression (OR, 4.37; 95% CI, 1.64-11.63; P = .02), and higher HOMA2 scores (β = 0.05; 95% CI, 0.01-0.62, P = .04) compared with participants with persistently low CRP. The late peak group was not associated with any outcomes at age 24 years.

Conclusions and Relevance  

Low-grade systemic inflammation peaking in midchildhood was associated with specific mental and cardiometabolic disorders in young adulthood. These findings suggest that low-grade persistent inflammation in early life may be an important shared common factor for mental-physical comorbidity and so could be relevant to future efforts of patient stratification and risk profiling.