A study published in the American Journal of Pediatric Psychology finds that children with autism have elevated blood pressure, even after adjusting for other health issues.
The researchers, led by the University of Minnesota, examined data from 2,000 children ages 3 to 13.
They found that nearly 30 percent had abnormal blood pressures, and more than half had hypertension, or high blood pressure.
The findings were the first to show that abnormal blood-pressure readings are associated with a variety of health problems.
“I’m not saying that blood pressure is an issue, but it does raise a lot of questions,” says lead author Andrew A. Dyer, a researcher at the University at Buffalo and the Institute for Social Research.
Dyer says he was surprised by the results.
“We had no idea there was this relationship,” he says.
Dyers and his colleagues used data from the Minnesota Children’s Hospital’s annual surveys of children and their parents to analyze data from 2006 to 2014.
Researchers took into account many other factors besides blood pressure — such as diet, medication use and health insurance coverage — that may have contributed to abnormal readings.
They looked at children whose blood pressure was elevated in both years, compared with those with no elevated readings.
And they looked at whether blood pressure spiked during the study.
“The question is, how do you determine that blood pressures are rising?”
Blood pressure spiked in children with the most elevated readings in both 2007 and 2014, when the researchers used the Minnesota Health and Nutrition Examination Survey (NHANES).
Those with elevated readings were more likely to be in poor health, and to have higher blood-sugar levels than those with normal readings.
Researchers say this suggests that blood- pressure can change dramatically in the days and weeks after birth.
But blood pressure doesn’t spike during the first few weeks of life.
“In the first weeks of pregnancy, we don’t know what that does to the blood-brain barrier,” says Dyer.
“When you go to a baby’s birth, you don’t really know how your body is going to react.”
Dyer and his team tested the blood of the children for several things, including hemoglobin, a protein that is a marker for the body’s oxygen level.
The researchers found that the children who had elevated blood-oxygen levels had higher hemoglobin levels than the children with normal blood pressure readings.
“That’s a pretty significant finding,” Dyer explains.
“The problem with blood pressure data is that it doesn’t tell us the absolute blood pressure,” says Rachael Pritchard, director of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), a division of the NIH.
“You might have blood pressure of 110, and it might not have been as high as 110.”NIDDC researchers looked at data from NHANES from 2005 to 2015 and found that blood vessels and blood vessels in the brain were not the same in people with abnormal blood or normal blood.
That may have been because of factors such as low birth weight and low birthweight infants, or birth defects, or a lack of oxygen in the womb.
“Our data shows that when you look at the normal blood and the abnormal blood, there’s a lot more variability,” Pritcher says.
“So we have to look at more than just the blood, we have a lot to look in.”
For more information on the study, go to the American Academy of Pediatrics website at: www.aap.org/pubs/2016/07/blood-pressure-unusual-blood-oxygene-predicts-autism-high-bloodsugar.htm