The role of inflammation in the prospective associations between early childhood sleep problems and ADHD at 10 years: findings from a UK birth cohort study

Role of Inflammation in Short Sleep Duration Across Childhood and Psychosis in Young Adulthood

Importance

Short sleep duration over a prolonged period in childhood could have a detrimental impact on long-term mental health, including the development of psychosis. Further, potential underlying mechanisms of these associations remain unknown.

Objective

To examine the association between persistent shorter nighttime sleep duration throughout childhood with psychotic experiences (PEs) and/or psychotic disorder (PD) at age 24 years and whether inflammatory markers (C-reactive protein [CRP] and interleukin 6 [IL-6]) potentially mediate any association.

Design, Setting, and Participants

This cohort study used data from the Avon Longitudinal Study of Parents and Children. Data analysis was conducted from January 30 to August 1, 2023.

Exposures

Nighttime sleep duration was collected at 6, 18, and 30 months and at 3.5, 4 to 5, 5 to 6, and 6 to 7 years.

Main Outcomes and Measures

PEs and PD were assessed at age 24 years from the Psychosislike Symptoms Interview. CRP level at ages 9 and 15 years and IL-6 level at 9 years were used as mediators. Latent class growth analyses (LCGAs) were applied to detect trajectories of nighttime sleep duration, and logistic regressions were applied for the longitudinal associations between trajectories of nighttime sleep duration and psychotic outcomes at 24 years. Path analyses were applied to test CRP and IL-6 as potential mediators.

Results

Data were available on 12 394 children (6254 female [50.5%]) for the LCGA and on 3962 young adults (2429 female [61.3%]) for the logistic regression and path analyses. The LCGA identified a group of individuals with persistent shorter nighttime sleep duration across childhood. These individuals were more likely to develop PD (odds ratio [OR], 2.50; 95% CI, 1.51-4.15; P < .001) and PEs (OR, 3.64; 95% CI, 2.23-5.95; P < .001) at age 24 years. Increased levels of IL-6 at 9 years, but not CRP at 9 or 15 years, partially mediated the associations between persistent shorter sleep duration and PD (bias-corrected estimate = 0.003; 95% CI, 0.002-0.005; P = .007) and PEs (bias-corrected estimate = 0.002; 95% CI, 0-0.003; P = .03) in young adulthood.

Conclusions and Relevance

Findings of this cohort study highlight the necessity of addressing short sleep duration in children, as persistence of this sleep problem was associated with subsequent psychosis. This study also provides preliminary evidence for future targeted interventions in children addressing both sleep and inflammatory responses.

Early childhood sleep quantity, but not caregiver-reported sleep problems, predicts impulse control in children at age 8 years

Short duration of sleep and poor sleep quality have been linked to poor attention and impulse control in children. We aimed to determine the longitudinal predictive value of sleep quantity and quality during early childhood on objective and caregiver-report measures of attention, impulse control, and executive function in children at age 8 years. We used data from the Health Outcomes and Measures of the Environment (HOME) Study, a pregnancy and birth cohort. Caregivers reported on their child's sleep at ages 2, 2.5, 3, 4, and 5 years. Analysis included 410 participants. We used longitudinal growth curve models of early childhood sleep patterns to predict neurobehavioral functioning at age 8 years. Sleep problems did not predict any of our outcome measures at age 8 years. Sleep duration trended shorter as children matured, so predictive models examined both intercept and slope. Children with the least decline in sleep duration across early childhood had fewer impulsive errors at age 8 years on a continuous performance test (unadjusted p = .013; adjusted p = .013). Children with shorter duration of sleep across early childhood had worse caregiver-reported behavioral regulation at age 8 years (unadjusted p = .002; adjusted p = .043). Neither sleep duration slope nor intercept predicted inattention or metacognitive skills at age 8 years (p > .05). Total sleep time across early childhood predicts behavior regulation difficulties in school-aged children. Inadequate sleep during early childhood may be a marker for, or contribute to, poor development of a child's self-regulatory skills.

The Association between Glucose 6-Phosphate Dehydrogenase Deficiency and Attention Deficit/Hyperactivity Disorder

BACKGROUND

Glucose-6-phosphate dehydrogenase (G6PD) deficiency, impacting 4.9% of the population and more prevalent in Mediterranean communities, is a common enzymopathy with potential relevance to Attention Deficit/Hyperactivity Disorder (ADHD). This study investigated this association.

METHODS

The clinical characteristics of 7473 G6PD-deficient patients and 29,892 matched case-controls (selected at a 1:4 ratio) from a cohort of 1,031,354 within the Leumit Health Services database were analyzed using Fisher's exact test for categorical variables and the Mann-Whitney U test for continuous variables.

RESULTS

In total, 68.7% were male. The mean duration of follow-up was 14.3 ± 6.2 years at a mean age of 29.2 ± 22.3 years. G6PD deficiency was associated with an increased risk of being diagnosed with ADHD (Odds Ratio (OR) = 1.16 [95% CI, 1.08-1.25], p < 0.001), seeking care from adult neurologists (OR = 1.30 [95% CI, 1.22-1.38], p < 0.001), and consulting adult psychiatrists (OR = 1.12 [95% CI, 1.01-1.24], p = 0.048). The use of stimulant medications among G6PD-deficient individuals was 17% higher for the methylphenidate class of drugs (OR = 1.17 [95% CI, 1.08, 1.27], p < 0.001), and there was a 16% elevated risk for amphetamine use (OR = 1.16 [95% CI, 1.03, 1.37], p = 0.047).

CONCLUSIONS

G6PD deficiency signals an increased risk of ADHD diagnosis, more severe presentations of ADHD and a greater need for psychiatric medications to treat ADHD.