Leyvraz M, et al. - High BP variability makes diagnosing children with sustained elevated blood pressure (BP) difficult, so researchers evaluated the tracking of BP and the persistence of elevated BP across childhood and adolescence. During childhood and adolescence, having an elevated BP on one occasion was shown to be a weak predictor of elevated BP 3–4 years later. Relative to younger and nonobese children, tracking was larger in older and obese children.

Methods

• Researchers examined three cohorts of children from schools in the Seychelles on two occasions at 3–4-year intervals.
• Obesity was defined as BMI at least 95th sex-specific and age-specific percentile.
• The average of two readings was used as the basis for BP on each visit, and elevated BP was defined as BP in at least the 95th sex-specific, age-specific, and height-specific percentile.

Results

• They gathered data in 4,519 children with mean ages of 5.5 and 9.2 years, 6,065 of ages of 9.2 and 12.5 years, and 5,967 of ages of 12.5 and 15.6 years, respectively.
• The reported incidence of elevated BP was 10% at age 5.5 years, 10% at 9.2 years, 7% at 12.5 years, and 9% at 15.6 years.
• Researchers found that among children with elevated BP at the initial visit, the persentages who had elevated BP at the subsequent visit 3–4 years later was 13% between ages of 5.5 and 9.2 years, 19% between 9.2 and 12.5 years, and 27% between 12.5 and 15.6 years.
• Among obese children with elevated BP, these proportions were higher, that is, 33, 35, and 39%, in each cohort, respectively.
• For SBP (range of tracking coefficients: 0.23–0.40) vs for DBP (range: 0.19–0.35), tracking coefficients were reported to be slightly larger, and increased with age.
• By comparison, tracking coefficients for BMI were found to be much higher (range: 0.74–0.84).