Obese children and teens have a significantly greater risk for developing hypertension compared with normal weight peers, study results indicate.
Hypertension rates were more than fourfold higher in moderately obese children (prevalence ratio 4.43; 95% CI: 4.10-4.79) and more than 10fold higher in extremely obese children (PR 10.76; 95% CI 9.99-11.59), after adjusting for sex, age and race/ethnicity, Corinna Koebnick, PhD, of Kaiser Permanente Southern California (KPSC) in Pasadena, and colleagues reported in the Journal of Clinical Hypertension.
The likelihood of developing hypertension was less pronounced, but still elevated in overweight children and teens (PR 2.27, 95% CI 2.08-2.47).
“Our findings strongly support the need for recommendations to screen for hypertension in overweight and obese children at all outpatient medical visits,” the researchers wrote.
Opinion over whether universal, routine pediatric hypertension screening policies should be instituted is currently divided. Several organizations, including the American Academy of Pediatrics; the National High Blood Pressure Education Program; the National Heart, Lung and Blood Institute; and the American Heart Association currently recommend such policies. However, others, including the U.S. Preventive Services Task Force (USPSTF) and the American Academy of Family Physicians, do not.
An alternative to universal pediatric hypertension screening, could be targeting high-risk populations, including obese children, as obesity is a well established risk factor for hypertension. To examine the relationship between different BMIs and BP levels, Koebnick and colleagues examined data from the Children’s Health Study conducted at KPSC.
The analysis involved data from 237,248 patients ages 6 to 17 years who were enrolled in the KPSC integrated prepaid health plan, and excluded those with pre-existing conditions known to affect growth or BP.
Patients were considered to have hypertension if they filled at least one prescription for an antihyptensive and had an outpatient diagnosis of hypertension or had high BP readings (defined as 95th percentile or higher, or at least 140/90 mm Hg even if lower than the 95th percentile) at the last three visits.
Prehypertension was defined as at least one BP reading from the 90th percentile to less than the 95th percentile — or at least 120/80 mm Hg even if lower than the 90th percentile — according to age, sex, and height charts.
Overall, 31.4% had prehypertension and 2.1% had hypertension, the researchers found. Hypertension prevalence increased according to BMI category and was a follows:
- 0.6% of underweight children had a BMI-for-age less than the 5th percentile
- 0.9% of normal-weight children had a BMI-for age from the 5th to less than the 85th percentile
- 2.0% of overweight children had a BMI-for-age from the 85th percentile to less than 95th percentile, or a BMI of 25 to less than 30 kg/m2
- 3.8% of moderately obese children had a BMI-for-age from the 95th percentile to less than 1.2 times the 95th percentile or a BMI of 30 to less than 35 kg/m2
- 9.2% of extremely obese children had a BMI-for-age at least 1.2 times the 95th percentile or a BMI of at least 35 kg/m2
“Our results suggest that the risk of hypertension in extremely obese children is more than twice that of moderately obese children,” the researchers wrote. “This may have serious clinical implications for pediatric populations that have experienced a recent increase in the prevalence of extreme obesity.”
However, they added more long-term studies are necessary to track children with hypertension into adulthood to determine their likelihood for developing other cardiovascular risk factors.