Visceral Fat Associated With Increased Arterial Stiffness in Youth With Obesity

Joseph M. Kindler, PhD

New research dove into associations between visceral fat and arterial stiffness in youth with healthy weight, obesity, and type 2 diabetes (T2D), in order to discover whether the relationships were independent of body fatness estimates as a predictor of cardiovascular events.

A team of investigators, led by Joseph M. Kindler, PhD, Department of Nutritional Sciences, University of Georgia, observed increased visceral fat had an association with increased arterial stiffness independent of body mass index in youth with obesity, but not in youth with healthy weight.

What were the methods?

As a point of note, the CVD in Adolescents with Type 2 Diabetes Study was a cross-sectional case-control study aimed at identifying effects of obesity and youth-onset T2D on the risk factors for cardiovascular disease. However, visceral fat was not studied regarding CV outcomes.

Thus, investigators performed a secondary analysis of cross-sectional data in youth aged 10 - 23 years old, with healthy weight (n = 236), obesity (n = 224), and T2D (n = 145). It was noted that the subjects were 67% female and 56.4% self-reported Black ethnicity.

In the study, visceral fat was assessed via dual-energy X-ray absorptiometry, while carotid-femoral pulse wave velocity (PWV) was assessed via applanation tonometry. Additionally, BMI was calculated, followed by height, weight, and BMI Z-scores. Hemoglobin A1c, insulin and glucose were assessed using standard clinical techniques.

In the analysis, investigators performed linear regression, with analysis into visceral fat interaction and PWV where subjects with T2D were combined into the obesity group.

Further, the regression models accounted for ancestry (Black or non-Black), sex (male or female), age, and mean arterial pressure (MAP).

What were the findings?

Kindler and colleagues observed the obese and T2D group had greater weight Z-score, BMI Z-score, HbA1c, insulin, glucose, visceral fat, subcutaneous fat, PWV, and MAP, in comparison to the healthy weight group (P <.01).

They saw the T2D group had greater height-Z score than the healthy weight group (P = .013) and greater HbA1c, insulin, glucose, visceral fat, and MAP, compared to the obese group (P <.05).

Additionally, visceral fat had positive associations with PWV in the 3 groups (P <.05) and the 95% confidence intervals for healthy weight, obesity, and T2D group showed similar associations between visceral fat and PWV.

Investigators observed a significant interaction between group and visceral fat in comparison to PWV, after accounting for ancestry, sex, age, and MAP (P <.001). In comparison to the healthy weight group, the obesity group and T2D group had stronger associations between visceral fat and PWV (P <.001).

Then, in the obesity group, but not the healthy weight group, visceral fat was positively associated with PWV. The team noted that it was predictive of PWV beyond BMI and waist circumference (P <.001).

When included in the same regression model, investigators observed visceral fat (P <.005), but not subcutaneous, had positive associations with PWV. Additionally, BMI remained positively associated with PWV (P <.001).

What were the takeaways?

The team concluded that visceral fat plausibly contributed to subclinical cardiovascular complications in youth.

“That visceral fat was associated with increased arterial stiffness in youth with obesity, irrespective of standard clinical estimates of body fatness, suggests that assessment of visceral fat might complement standard clinical measures of body fatness in identifying youth at risk for obesity-related chronic disease,” investigators wrote.

The study, “Visceral fat and arterial stiffness in youth with healthy weight, obesity, and type 2 diabetes,” was published in Pediatric Obesity.