Assessment of peak systolic velocity (PSV) of the internal carotid artery (ICA) is utilized to examine stroke-symptomatic individuals for ICA stenosis. While a sedentary lifestyle is a common risk factor for ICA stenosis, a deeper understanding of how body composition affects ICA blood flow could provide insights before symptoms appear. PURPOSE: To examine the relationship between ICA blood flow and body composition variables. METHODS: ICA blood flow was assessed in eight healthy males (21.88 ± 2.25 years) on three different days to control for possible diurnal variability that could affect blood flow. Participants abstained from caffeine and physical activity for a minimum of 12 hours prior to each visit. Dual-energy X-ray absorptiometry was used to assess body fat percentage (BF%) and visceral fat area (VFA). Bioelectrical impedance (BIA) was used to assess body water percentage (BW%), metabolic age (MetA), and visceral fat rating (VFR). Participants rested supine with eyes closed for 5 minutes prior to assessment of ICA. B-mode doppler ultrasound sonography (7.5 MHz linear transducer) was used to measure PSV, end-diastolic velocity (EDV), resistance index (RI), and vessel diameter on the right ICA after 2 minutes of continual scanning with a 60° insonation angle. The relationship between ICA blood flow and body composition variables was examined via Pearson correlation analysis. RESULTS: BF% was positively correlated with ICA EDV (r = 0.669, p \u3c 0.001) and ICA PSV (r = 0.416, p = 0.043) but negatively correlated with ICA diameter (r = -0.424, p = 0.039). VFA was positively correlated with ICA EDV (r = 0.505, p = 0.012). BW% was negatively correlated with ICA PSV (r = -0.417, p = 0.043) and EDV (r = -0.620, p \u3c 0.001). MetA was positively correlated with ICA EDV (r = 0.630, p \u3c 0.001) but negatively correlated with ICA RI (r = -0.509, p = 0.011) and diameter (r = -0.513, p = 0.010). Similarly, VFR was positively correlated with ICA EDV (r = 0.644, p \u3c 0.001) but negatively correlated with ICA RI (r = -0.511, p = 0.011) and diameter (r = -0.496, p = 0.014). CONCLUSION: EDV has a greater correlation with body composition than PSV, suggesting that adiposity-related factors can describe ICA blood flow. Similarly, BIA might offer a solid and easy-to-attain procedure to indirectly assess ICA blood flow that warrants further research
