GLYCEMIC control, as indicated by glycated hemoglobin (HbA1c), is inversely associated with heart-rate variability (HRV) and functional connectivity (FC) in healthy adults, with notable age- and sex-related differences, recent research has shown.
This study aimed to explore the relationships between glycemic control, autonomic nervous system (ANS) function, and brain connectivity in healthy individuals. Data were derived from the Leipzig Study for Mind-Body-Emotion Interactions (LEMON), comprising 146 adults (114 young, 32 older). Glycemic control was assessed via HbA1c, ANS activity through heart-rate variability metrics (RMSSD and high-frequency HRV), and autonomic brain function using resting-state FC in the salience-central autonomic network (S-CAN) and salience network (SN). The study investigated how these associations varied by age and sex.
Analyses revealed that higher HbA1c was linked to lower FC in the S-CAN but not the SN, and also to reduced HRV. Additionally, both RMSSD and log(HF-HRV) were positively correlated with FC in both networks. Importantly, age-related differences were observed in the HbA1c-FC relationship, with stronger correlations in older adults, while sex-related differences emerged in the HRV-FC associations, being more pronounced in females. Younger adults exhibited lower HbA1c and higher HRV compared to older adults, and no sex-based differences were found in HbA1c.
These findings highlight the interplay between glycemic control and autonomic brain function, extending diabetes-related research to healthy populations. The observed age- and sex-related differences suggest that these factors should be carefully considered in future investigations. Clinically, the results highlight the importance of glycemic regulation even in non-diabetic populations, particularly for maintaining autonomic and cognitive health across the lifespan. Further research is needed to explore whether targeted interventions to improve glycemic control can enhance autonomic and brain function, especially in older adults and females.
Katrina Thornber, EMJ
Reference
Yu JX et al. The associations among glycemic control, heart variability, and autonomic brain function in healthy individuals: Age- and sex-related differences. Neurobiol Aging. 2024;142:41-51.
