Intensified Adiposity Effect on BP in Overweight Children
Four-fold increase in effect noted when child's BMI reaches 85th percentile
MONDAY, Oct. 3 (HealthDay News) -- The effect of adiposity on blood pressure (BP) in children is minimal until the body mass index (BMI) reaches the 85th percentile, at which point it intensifies, according to a study published online Oct. 3 in Hypertension.
Wanzhu Tu, Ph.D., from Indiana University School of Medicine in Indianapolis, and colleagues investigated whether the full range of adiposity in childhood correlated with BP and risk of hypertension. A total of 1,111 children with a mean age of 10.2 years underwent 9,102 semiannual BP and height/weight assessments during an average follow-up of 4.5 years. To account for the effect of age and gender, adiposity was measured as BMI percentiles. At least one blood serum sample was obtained from a majority of the participants and leptin concentrations were measured.
The investigators identified minimal effect of relative adiposity on BP until the BMI percentile reached 85. At this point, there was a four-fold increase in the effect of adiposity on BP. The children aged 10 years or younger, 11 to 14 years old, and 15 years or older expressed a similarly intensified effect of adiposity on BP. The relationship of serum levels of leptin and heart rate with BP was almost identical to the pattern of the relationship between BMI percentile and BP.
"There is a marked intensification of the influence of adiposity on BP when children reach the categories of overweight and obese. Among the possible pathways, leptin may be a potentially important mediator acting through the sympathetic nervous system (reflected in heart rate)," the authors write.