Children exposed to two or more anaesthetics before age 3 had more than double the incidence of ADHD than children who had no exposure, says Doctor David Warner, a Mayo Clinic paediatric anaesthesiologist and investigator on the observational study.
When basic science studies in the medical literature began to suggest anaesthesia used in surgery causes changes in the brains of young animals, Warner and a group of researchers at Mayo Clinic took note.
"Those studies piqued our interest," Warner says. "We were sceptical that the findings in animals would correlate with kids, but it appears that it does."
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.
Among 341 cases of ADHD in those younger than 19, researchers traced medical records in the Rochester Epidemiology Project, a decades-long database of all patient care in Olmsted County, Minn., looking for exposure to anaesthesia and surgery before age 3.
Children who had no exposure to anaesthesia and surgery had ADHD at a rate of 7.3 percent. The rate after a single exposure to anaesthesia and surgery was approximately the same. For children who had two or more exposures to anaesthesia and surgery, the rate of ADHD was 17.9 percent, even after researchers adjusted for other factors, including gestational age, sex, birth weight and comorbid health conditions.
The results of the study, however, do not definitively mean that anaesthesia causes ADHD, Warner says: "This is an observational study. 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."
MEDICA.de; Source: Mayo Clinic