September 9, 2013
More Research Needed To Better Understand Caffeine Addiction
[ Watch the Video: Caffeine Addiction In The Spotlight ]
Lee Rannals for redOrbit.com - Your Universe Online
Caffeine is one of the two most widely used psychoactive drugs on the planet, second only to alcohol. Studies have shown that it only takes an average of two-and-a-half cups of coffee per day to become addicted.
Researchers from several institutions reviewed published research on caffeine dependence and determined that future studies need to be conducted in order to better understand the clinical signs and the prevalence of caffeine dependence, as well as the risk factors and best approaches for treating the addiction.
“Caffeine-related problems are increasingly being seen as clinically important by addiction professionals,” says Jack E. James, PhD, Editor-in-Chief of the journal. “The article by Dr. Steven Meredith and colleagues is timely in helping to clarify the dimensions of caffeine dependence problems, while also providing direction for future research in this neglected area.”
The authors wrote that caffeine withdrawal has been shown to occur in a range of nonhuman animal species, and clearly defined caffeine withdrawal syndrome has been well documented in humans as well. Symptoms of caffeine withdrawal can include headache, fatigue, difficulty concentrating, and dysphoric mood.
The World Health Organization (WHO) recognizes a diagnosis of Caffeine Dependence Syndrome, which is defined as a cluster of behavioral, cognitive, and physiological phenomena that develop after repeated substance use.
Scientists conducted searches on several research databases that included 122 studies. Participants in the studies had to meet the authors' "inclusion criteria" before being used.
"The literature reviewed in this article shows that caffeine produces behavioral and physiological effects similar to those produced by other drugs of dependence," the authors wrote. "Indeed, an abundance of evidence from controlled laboratory studies with human and nonhuman animal subjects demonstrates the biological plausibility of caffeine dependence. Further, a number of recent clinical studies show that a nontrivial proportion of caffeine users develops clinically meaningful features of caffeine dependence, including a persistent desire or unsuccessful efforts to cut down or control caffeine use, continued use despite harm, and a characteristic withdrawal syndrome."
They said that although WHO already recognizes a diagnosis of Caffeine Dependence Syndrome, there is a "critical need" for more clinical, epidemiological, and genetic research on caffeine dependence. The scientists said no national population-based study has been conducted so far that looks into the prevalence and severity of caffeine dependence in the general population. They also wrote that most studies that have characterized caffeine dependence relied on relatively small samples sizes.
"Nevertheless, several recent reports have shown that caffeine dependence can result in clinically significant distress and functional impairment, and many individuals are sufficiently distressed by their caffeine dependence to seek treatment," the authors said.
The team said more research is needed to help scientists determine which methods work best to treat individuals who are currently distressed by caffeine addiction.
Contributing authors to this review include Dr. Steven E. Meredith and Roland R. Griffiths of Johns Hopkins University School of Medicine, Laura M. Juliano of American University and John R. Hughes of University of Vermont.