Study Assesses Brain Volume Differences in Girls with Central Precocious Puberty

An imaging study of girls with idiopathic CPP and matched controls suggests idiopathic CPP was associated with increased gray matter and white matter volumes in the cerebral area.

New research from an imaging study assessing differences in brain volume among girls with idiopathic central precocious puberty (ICPP) against cohorts of healthy age-matched and normal puberty cohorts could provide insight into the neuroanatomical mechanisms on morphological variations associated with ICPP.

Results of the study, which included data from 15 girls with ICPP and matched controls, offer clinicians with an overview of the potential for volumetric differences in brain volume and correlations with differences in luteinizing hormone (LH) levels in patients with ICPP compared with those age-matched and normal puberty controls.

“These findings will be useful for understanding the neuroanatomical mechanisms on the specific morphological variations associated with ICPP,” wrote investigators.

Citing a lack of studies assessing differences in brain structure among patients with early puberty to other individuals, a team from Chonnam National University and Chosen University Hospital in Korea designed the current study to fill with apparent knowledge gap. Specifically, the study was designed to compare cerebral volume differences between ICPP girls, age-matched girls, and normal puberty girls using voxel-based morphometry as well as examining potential influence of LH on brain structure.

To do so, investigators created their 3 cohorts using patients recruited from the Department of Pediatrics at Chosun University Hospital. All individuals included in the study underwent anatomical imaging with 1.5 Tesla Avanto MR scanner and T1-weighted images were acquired with a T1 spin-echo sequence. Investigators compared volumes of total and regional brain using paired T-tests. Of note, luteinizing hormone levels were assessed through a correlation test.

The mean age of the ICPP group, age-matched group, and puberty group were 8.0±0.9 years, 7.8±0.9 years, and 11.9±0.9 years, respectively. Investigators noted the 15 girls with ICPP had advanced bone age and breast development. Investigators also noted peak LH levels stimulated by the gonadotropin-releasing hormone agonists (GnRHa) of ICPP girls were 15.9±14.9 mIU/mL. There were no significant differences in total intracranial volume observed among the cohorts, with TICV of 1194.6±122.4 ml for ICPP girls, 1139.0±75.5 ml for age-matched controls, and 1173.93±68.93 mL for normal puberty controls.

Investigators’ analyses indicated cerebral volumes in patients with ICPP were different from those of the age-matched cohorts. Specifically, ICPP was associated with a significant increase in gray matter (GM) volumes in the medial prefrontal cortex, superior parietal gyrus, supramarginal gyrus, angular gyrus, postcentral gyrus, superior occipital gyrus, cuneus, hippocampus, parahippocampal gyrus, posterior cingulate gyrus (PCgG), and cerebellar cortex (Cb) and in white matter (WM) volumes in the insular, caudate, and splenium of corpus callosum (P <.001)).

Investigators pointed out GM volumes of the PCgG (r=.57, P=.03)) and Cb (r=.53. P=.04) were positively correlated with LH concentrations stimulated by GnRHa. However, investigators also pointed out there were no significant differences in GM volume observed when comparing the ICPP cohort to the normal puberty controls.

“Increased GM and WM volumes were observed in the whole cerebral area of ICPP girls compared to the age-matched control group. These observed brain regions were related to emotional and cognitive function, and correlated with the sex hormone additionally,” wrote investigators. “This suggests that the cerebral development pattern of ICPP is similar to that of normal puberty, and these local differences in cerebral volume may affect social and congenital changes.”

This study, “The Assessment of Brain Volume Differences in Idiopathic Central Precocious Puberty Girls; Comparison of Age-Matched Girls and Normal Puberty Girls,” was published in Children.