The influence of vascular risk factors and aging on choroid plexus enlargement

Using a large elderly population cohort, we investigated the relationship between choroid plexus (CP) volume, a potential indicator of glymphatic system activity, and lifestyle-related vascular risk and protective factors, as well as age-related changes in CP volume.

This cross-sectional study included 2137 participants (median age, 70 years) who underwent 3-T MRI and vascular risk factor assessment. Factors included body mass index (BMI), systolic blood pressure (SBP), total cholesterol, hemoglobin A1c (HbA1c), smoking (Brinkman Index), and physical activity (International Physical Activity Questionnaire). Multiple regression analyses were conducted, adjusting for total intracranial volume (TIV), age, gender, and medication use.

CP volume significantly increased with age (r = 0.351, p < 0.001). Among the vascular risk factors, only a higher Brinkman Index (smoking) was significantly associated with a larger CP volume in the overall analysis (β = 0.075, FDR-corrected p < 0.001). In sex-specific analyses, higher systolic blood pressure and an increased Brinkman Index were associated with larger CP volumes in males. In females, no vascular risk factors remained significant after correction for multiple comparisons. These factors explained only a small proportion of the variance in CP volume (R² = 0.013).

In this large cohort of older adults, choroid plexus volume increases with age. Sex-specific analyses revealed that systolic blood pressure and smoking were significant risk factors in males, while no significant associations were found in females. However, these vascular factors explained only a small proportion of the variance in CP volume.

Question How do lifestyle-related vascular risk factors like hypertension, smoking, and obesity affect choroid plexus volume, a potential indicator of glymphatic function? Findings In this elderly cohort, choroid plexus volume increased with age and was associated with smoking; males showed an additional significant association with higher blood pressure. Clinical relevance Understanding the sex-specific links between vascular risk factors and choroid plexus volume is crucial for developing targeted strategies to preserve glymphatic function and brain health in aging populations.