Congenital Adrenal Hyperplasia and Brain Health: A Systematic Review of Structural, Functional, and Diffusion Magnetic Resonance Imaging (MRI) Investigations

Endocrine, cardiac and neuropsychological aspects of adult congenital adrenal hyperplasia

OBJECTIVE

To investigate the metabolic, cardiovascular, and neuropsychological phenotype, quality of life (QoL), and hormonal regulation in individuals with congenital adrenal hyperplasia (CAH), a group of autosomal recessive disorders characterized by impaired synthesis of cortisol in the adrenal cortex and, if untreated compensatory hyperandrogenism. CAH is associated with an increased cardiovascular and metabolic morbidity, possibly due to overtreatment with glucocorticoids, leading to weight gain, insulin resistance, and metabolic syndrome.

DESIGN, PARTICIPANTS, MEASUREMENTS

Thirty-seven individuals with CAH and 33 age- and sex-matched controls were evaluated at a single centre at Aarhus University Hospital with echocardiography, electrocardiogram, 24-h blood pressure, biochemistry, anthropometrics, and autism spectrum, anxiety, depression, personality, cognitive failures, and QoL were assessed using questionnaires.

RESULTS

CAH individuals had lower height than controls (170.5 vs. 182.9 cm in males and 160.2 vs. 170.1 cm in females, p < 0.01). Compared with female controls, females with CAH had higher haemoglobin (8.8 vs. 8.2 mmol/L, p = 0.003) and BMI (29.7 vs. 25.5 kg/m2, p = 0.006), reduced insulin sensitivity (HOMA-IR): 2.7 vs. 1.9, p = 0.018), prolonged E-wave deceleration time (193 vs. 174 cm, p = 0.015), and E/é ratios (5.4 vs. 4.5, p = 0.017), and lower self-reported QoL. Males with CAH had more cognitive complaints (p = 0.034) and higher autistic scores (19.9 vs. 14.9; p = 0.068) compared with male controls. More individuals with CAH than controls reported writing problems.

CONCLUSION

A sex-specific comorbidity profile is evident in CAH, with females presenting with decreased metabolic and overall self-reported health, whereas males with CAH presented with increased cognitive complaints and autistic traits.

Remembering the null hypothesis when searching for brain sex differences

Human brain sex differences have fascinated scholars for centuries and become a key focus of neuroscientists since the dawn of MRI. We recently published a major review in Neuroscience and Biobehavioral Reviews showing that most male-female brain differences in humans are small and few have been reliably replicated. Although widely cited, this work was the target of a critical Commentary by DeCasien et al. (Biol Sex Differ 13:43, 2022). In this response, I update our findings and confirm the small effect sizes and pronounced scatter across recent large neuroimaging studies of human sex/gender difference. Based on the sum of data, neuroscientists would be well-advised to take the null hypothesis seriously: that men and women's brains are fundamentally similar, or "monomorphic". This perspective has important implications for how we study the genesis of behavioral and neuropsychiatric gender disparities.

Altered Emotion Perception Linked to Structural Brain Differences in Youth With Congenital Adrenal Hyperplasia

CONTEXT

Congenital adrenal hyperplasia (CAH) is a genetic disorder that results in hormonal imbalances and decreased brain volumes in regions important for emotional processing.

OBJECTIVE

To examine whether emotion perception differs between youth with CAH and control youth, and if these differences relate to brain volumes.

METHODS

In this cross-sectional study of 27 youths with CAH (mean age = 12.63 years, 16 female) and 35 age- and sex-matched controls (mean age = 13.03 years, 20 female), each participant rated picture stimuli and completed a 3T structural brain scan. Valence and arousal ratings and reaction times of 61 affective images were assessed. Gray matter volumes were measured by MRI.

RESULTS

Youth with CAH had lower valence ratings for negative (P = .007) and neutral (P = .019) images. Controls showed differences in reaction times and arousal ratings across stimuli conditions, but youth with CAH did not. Brain volumes of the right amygdala (P = .025) and left hippocampus (P = .002) were associated with valence ratings. Left rostral middle frontal (P < .001) and right medial orbitofrontal cortex (P = .002) volumes were negatively related to valence scores only in youth with CAH, whereas left medial orbitofrontal cortex (P < .001) volumes were associated with valence scores positively in youth with CAH and negatively in controls.

CONCLUSION

Findings suggest that youth with CAH perceive emotive stimuli as more unpleasant. Decreased brain volumes in the amygdala, hippocampus, and prefrontal cortex are associated with these measures of altered emotion perception in youth with CAH.