Altered posterior cingulate brain metabolites and cognitive dysfunction in preterm adolescents

Area of Science:

• Neuroscience
• Developmental Biology
• Medical Imaging

Background:

• Extremely preterm (EP) individuals (<28 weeks gestation) face higher risks of cognitive deficits.
• The posterior cingulate's role in cognition is established, but its alteration by preterm birth remains unclear.
• Investigating brain metabolite differences in EP individuals is crucial for understanding cognitive outcomes.

Purpose of the Study:

• To compare brain metabolite ratios (neuronal and cell membrane markers) in 18-year-old extremely preterm individuals versus controls.
• To explore the association between these metabolite ratios and cognitive functions (IQ, memory, attention).

Main Methods:

• Proton magnetic resonance spectroscopy (MRS) measured cerebral metabolites in the posterior cingulate of 150 EP individuals and 134 controls.
• Key ratios analyzed were total N-acetylaspartate (tNAA)/total creatine (tCr) and total choline (tCho)/tCr.
• Linear and logistic regressions assessed group differences and correlations with cognitive test scores.

Main Results:

• EP individuals exhibited significantly lower tNAA/tCr and tCho/tCr ratios compared to controls (P=0.02).
• Higher tCho/tCr correlated with better IQ specifically in the EP group.
• Elevated tNAA/tCr ratios were associated with improved working memory and attention in both EP and control groups.

Conclusions:

• Extremely preterm birth is associated with lasting alterations in posterior cingulate brain metabolite ratios.
• These neurochemical changes may contribute to the observed long-term cognitive impairments in extremely preterm survivors.