Paula Moyer, MA

Medscape Medical News 2005

May 24, 2005 (Atlanta) — When parents or teachers complain about a child being inattentive, restless, and having difficulty sleeping, physicians may want to consider the caffeinated soft drinks in the school vending machine or the home refrigerator before they screen for attention deficit/hyperactivity disorder (ADHD), according to findings presented here at the 2005 American Psychiatric Association Annual Meeting. In a small double-blinded study of first-grade children, they had more behavior problems on the days that they were exposed to caffeinated colas than on the days that they had caffeine-free drinks. These findings may provide a simple answer to some instances of children's hyperactivity, according to principal investigator Alan R. Hirsch, MD. "We found that exposure to caffeinated cola drinks impaired children's learning ability by causing restlessness, hyperactivity, and inattention," Dr. Hirsch said. "On the days that the children were drinking caffeinated drinks, their Connors scores increased an average of 5.5 points compared with the days when they were only drinking caffeine-free drinks." Dr. Hirsch is the director of the Smell and Taste Treatment and Research Foundation in Chicago, Illinois, as well as an assistant professor of both neurology and psychiatry at Rush Medical College in Chicago. The study involved 20 first-grade children, 10 boys and 10 girls. In three-hour time segments that occurred sequentially for a two-week study period, the students were given up to 12 oz of either a caffeinated cola drink or a caffeine-free cola drink. The children were given 10 dimes with which they could "buy" repeat servings of their designated drink for the study session after an initial serving of 2 oz. At the end of each session, the children's teacher, who did not know the purpose of the study or the type of soda each child consumed, assessed each child's behavior with a modified Connors test. On the study days, the children consumed an average of 7.55 oz of caffeine-free cola and 9.45 oz of caffeinated cola (P = .03). On the days without caffeine, the children had an average modified Connors score of 1.55. On the days they drank caffeinated cola, the children had an average score of 7.00 (P = .002). Among the individual students, 60% had elevated Connors scores on the caffeine days, while 15% had higher scores on the caffeine-free days (P = .008). The remaining 25% had consumed the maximum servings of both types of drinks and were not included in the analysis.

After adjusting for noncaffeine-related factors, such as the number of ounces consumed and the amount of sugar in the drinks, the scores were still higher on the caffeine days (P = .015). The findings should support physicians' recommendations regarding restricting children's dietary caffeine, and it could also have implications regarding school systems' friendly relationship with vendors. "Children ages 6 to 11 years old conservatively drink an average of seven to eight oz of carbonated soda per day," said Dr. Hirsch. As the findings show, "this can have a substantial impact on children's behavior in school." "This is an interesting study, with findings consistent with prior findings," said David W. Fassler, MD, in a comment seeking an expert's perspective. "Although the sample size is small, the authors demonstrated that behavior difficulties can be caused by caffeinated beverages." Dr. Fassler is a clinical professor at the University of Vermont in Burlington and a member of the American Psychiatric Association's board of trustees. "The findings support physicians' conventional advice concerning the negative effects of caffeinated drinks on young children," Dr. Fassler added. "It also underscores why it is so important to completely evaluate young children who are having behavioral and emotional problems and to review the child's dietary habits, including caffeinated beverages, as part of the evaluation." Although questions about caffeine consumption are typically part of the screen for anxiety disorders, pediatric insomnia, and ADHD, the findings are a reminder not to neglect this part of the evaluation, Dr. Fassler said.

2005 APA Annual Meeting: Abstract NR45. Presented May 23, 2005.

Reviewed by Gary D. Vogin, MD

http://www.medscape.com/viewarticle/505467