High blood pressure can put a person at greater risk for a range of cardiovascular issues -- from heart attack to stroke. But if you think it's only an adult problem, think again.
The number of kids who have high blood pressure and what's called prehypertension, or borderline high blood pressure, has increased substantially in recent years. About 1 in 10 children and adolescents ages 8 to 17 has hypertension or is considered at risk for developing it, according to the latest survey and research data, which finds an estimated 1 to 3 percent of children and adolescents already have high blood pressure. The problem does seem to be leveling off somewhat, says Wei Perng, research assistant professor of nutritional sciences and epidemiology at the University of Michigan School of Public Health. "But it's concerning that this is happening at all in children, because really hypertension is supposed to be a disease of later life," she says. "The thought is [that] this is driven by the obesity epidemic that began in the '80s and really kind of spun out of control in the '90s [and] early 2000s."
Perng led research published online this month that evaluated the link between rapid weight gain very early in life and a child's risk of developing high blood pressure later. The study found that increases in body mass index, or BMI -- a measure of body fat based on weight and height -- in 0- to 6-month-olds and 2- to 3-year-olds was associated with higher systolic blood pressure. That's the top number in a blood pressure reading, which measures pressure in the arteries when the heart beats. "Our findings suggest that more rapid gain in body mass index during the first 6 postnatal months and in the preschool years may lead to higher systolic blood pressure in mid-childhood, regardless of size at birth," the researchers wrote in an American Heart Association journal Hypertension.
That's significant because children who have high blood pressure are much more likely to face the issue later in life. "It's entirely consistent with the trend in recent years identifying the rapid gain in weight in younger children -- infants and toddlers -- as a risk factor for the development of hypertension later on in adolescents and adulthood," says Dr. Alan Lewis, a pediatric cardiologist at Children's Hospital Los Angeles. He adds that the research provides additional insight into the early age ranges where fat gain seems to be associated with a hike in blood pressure later on.
The study includes more than 900 participants from Project Viva, an ongoing, long-term research study of women and children.
Experts say it's important to closely monitor a child's weight gain with your pediatrician to ensure it's within a healthy range. "Avoid the chubby baby syndrome," Lewis urges parents. "Historically a chubby baby was viewed as a healthy baby and a thriving baby and something to be encouraged." But more recent research -- reinforced by the study published in Hypertension -- has shown that added fat can adversely affect cardiovascular health, including by leading to high blood pressure.
Doctors also point out, however, that a finding of high blood pressure in a child could owe to many factors beyond weight gain, from a family history of hypertension to an underlying medical problem, like a heart malformation. While the study in Hypertension showed an association between more rapid weight gain during infancy and in toddlers with elevated blood pressure levels in mid-childhood, it didn't establish cause and effect, notes Dr. Cynthia Pan, a pediatric nephrologist, or kidney specialist, at the Children's Hospital of Wisconsin and professor of pediatrics at the Medical College of Wisconsin. "Based on this, we would not recommend [that parents place] infants on strict diets, and again, parents should always seek advice from a pediatrician about their infant's growth." However, for older kids, she reiterated recommendations that children who are obese are advised to combat the problem with healthy eating and exercise.
She also suggested that children ages 3 and up be routinely screened for hypertension. That's in line with recommendations from the American Academy of Pediatrics. However, the U.S. Preventive Services Task Force, an independent group of experts that makes recommendations on preventive care, says that current evidence is insufficient to weigh the benefits of screening asymptomatic children and adolescents against any potential harms, like side effects from children being put on blood pressure medication.
Dr. Joseph Block, a pediatric cardiologist at the Children's Hospital of Wisconsin and assistant professor of pediatrics at the Medical College of Wisconsin, says particularly in children, where so-called secondary hypertension is more common, it's important to first identify if there's an underlying medical cause for high blood pressure and treat that issue. That can also help clinicians gauge the short- and long-term implications for the child.
Kids with primary hypertension -- which isn't caused by an underlying medical problem but may be related to genetics and lifestyle factors, like weight gain -- can also face serious health consequences that affect both the heart and brain. Severe blood pressure elevation in children can cause hypertensive encephalopathy, or neurological dysfunction, Block says, in addition to hypertension raising the risk of heart problems and stroke down the road. "We're finding more and more that these kids [who] have elevated blood pressure [face] long-term complications."