Dr. David Warner, a Mayo Clinic pediatric anesthesiologist, and colleagues found children exposed to two or more anesthetics before age 3 had more than double the incidence of ADHD than children who had no exposure.
The study utilized results of an existing epidemiological study that looked at educational records of children born between 1976 and 1982 in Rochester, Minn., and determined those who developed some form of learning disability or ADHD.
Children who had no exposure to anesthesia and surgery had ADHD at a rate of 7.3 percent and the rate after a single exposure to anesthesia and surgery was approximately the same. However, for children who had two or more exposures to anesthesia and surgery, the rate of ADHD was 17.9 percent, even after researchers adjusted for other factors, including gestational age, sex, birth weight and co-morbid health conditions, Warner said.
The findings, published in the Mayo Clinic Proceedings, do not mean that anesthesia causes ADHD.
"This is an observational study," Warner said in a statement. "A wide range of other factors might be responsible for the higher frequency of ADHD in children with multiple exposures. The findings certainly do suggest that further investigation into this area is warranted, and investigators at Mayo Clinic and elsewhere are actively pursuing these studies."