Young adults with modifiable cardiovascular risk factors within the recommended range are more likely to have higher cerebral vessel density and caliber, greater cerebral blood flow, and fewer white matter hyperintensities, according to a cross-sectional, observational study published in JAMA.
A total of 125 individuals aged 18 to 40 years without evidence of cerebrovascular disease were included in the analysis. The investigators evaluated the number of modifiable cardiovascular risk factors and their association with cerebrovascular structure and function, as well as white matter hyperintensities. Risk factors at recommended levels were assigned a value of 1 to 8, with higher-value numbers associated with healthier risk categories.
The recommended risk factors and their associated recommended levels included having a body mass index of <25 kg/m2, rating in the highest tertile of cardiovascular fitness and/or physical activity, consuming <8 alcoholic drinks/week, being a nonsmoker for >6 months, having a blood pressure on awake ambulatory monitoring <130/80 mm Hg, having a nonhypertensive diastolic response to exercise (peak diastolic blood pressure <90 mm Hg), presenting with a total cholesterol level of <200 mg/dL, and having a fasting glucose level of <100 mg/dL.
In multivariable models, associations were observed between cardiovascular risk factors and cerebrovascular morphology, as well as white matter hyperintensity count. Vessel density and vessel caliber values were significantly greater by 0.3 vessels/cm3 (95% CI, 0.1-0.5; P =.003) and 8 μm (95% CI, 3-13; P =.01), respectively, for each additional modifiable risk factor assigned as healthy.
In addition, fewer white matter hyperintense lesions were observed for each cardiovascular risk factor categorized as healthy by 1.6 lesions (95% CI, −3.0 to −0.5; P =.006). In a subgroup of 52 patients assessed with magnetic resonance imaging, cerebral blood flow was 2.5 mL/100 g/minute higher for each healthier risk factor category (95% CI, 0.16-4.89; P =.03).
Limitations of the analysis include its small sample size, the recruitment of patients from a single center, and the cross-sectional design.
“[I]n this study group higher blood pressure was associated with reduced vessel density and antihypertensive use was associated with lower cerebral blood flow,” the researchers added. “Therefore, further work to identify optimal interventions in young adults to maintain autoregulation of cerebral blood flow, while reducing risk, may be required.”
Williamson W, Lewandowski AJ, Forkert ND, et al. Association of cardiovascular risk factors with mri indices of cerebrovascular structure and function and white matter hyperintensities in young adults. JAMA. 2018;320(7):665-673.