Link Between Caffeine Dependence and Family History of Alcoholism

A study led by Johns Hopkins investigators has shown that women with a serious caffeine habit and a family history of alcohol abuse are more likely to ignore advice to stop using caffeine during pregnancy.

Withdrawal symptoms, functional impairment and craving were cited by the women as reasons they could not cut out or cut back on caffeine use.

None of the women had a current alcohol-use diagnosis, and none had been treated for alcohol problems.

"Results of this study suggest that genetic vulnerability reflected in a family history of alcoholism may also be at the root of the inability to stop caffeine use," said co-lead author Roland R. Griffiths, Ph.D., a professor in the departments of Psychiatry and Neuroscience at The Johns Hopkins University School of Medicine.

The study appears in the December issue of the American Journal of Psychiatry.

Griffiths, whose past studies of caffeine use helped establish the drug's addictive nature, collected data on caffeine and alcohol use from 44 pregnant women seeking prenatal care from a private obstetrics and gynecology practice in a suburban community. Results showed that half of the women who had both a lifetime history of caffeine dependence and a family history of alcoholism ignored their doctor's recommendation to abstain from caffeine use and consumed caffeine in amounts greater than those considered safe during pregnancy.

Women in the study without these dual risk factors were able to abstain from caffeine during pregnancy, Griffiths said.

"This study helps to validate the diagnosis of caffeine dependence as a clinically significant phenomenon," Griffiths said. "It's one thing to speculate how powerful the dependence is, but here we have an example of people who are not following physician recommendations and are unable to quit caffeine in spite of wanting to do so."

Caffeine use during pregnancy has been associated with a variety of adverse consequences, including spontaneous abortion and reduced fetal growth. Government health agencies in the United States, Canada and the United Kingdom have issued health warnings about limiting the use of caffeine during pregnancy. The U.S. Food and Drug Administration has advised pregnant women to "avoid caffeine-containing foods and drugs, if possible, or consume them only sparingly," and Health Canada and the Food Standards Agency of the United Kingdom have advised that pregnant women consume less than 300 milligrams per day of caffeine, according to the study.

Co-lead author of the study, Dace S. Svikis, a part-time associate professor in the Department of Psychiatry and Behavioral Sciences at Hopkins, emphasized the clinical implications of the study for pregnancy and other medical conditions for which caffeine use is not recommended. "While the majority of women in the study reduced their caffeine intake throughout pregnancy, the subgroup of women with both risk factors appears to require intervention in addition to instructions from their physician in order to assure caffeine abstinence," Svikis said. Svikis is also a professor of psychology at Virginia Commonwealth University in Richmond, Va.