PULLMAN, Wash. — A new study by Washington State University researchers reveals physician office visits for the treatment of attention-deficit/hyperactivity disorder (ADHD) more than doubled between 1990 and 1995. The study also shows that stimulant prescriptions for drugs that treat the disorder, such as Ritalin, nearly tripled among children 5-18 years old.
The findings are published in an article in the April 1999 issue of Clinical Pediatrics. The article, “National Trends in the Prevalence of Attention-Deficit/Hyperactivity Disorder and the Prescribing of Methylphenidate Among School-Age Children: 1990-1995,” reports the results of a study conducted by Linda M. Robison and colleagues in the Pharmacoeconomics and Pharmacoepidemiology Research Unit at Washington State University’s College of Pharmacy.
The authors suggest reasons for these increasing trends include greater physician and public awareness of this condition, the persistence of ADHD into adolescence and adulthood, and the increasing rate of girls diagnosed with ADHD and treated with stimulant medication.
Robison and her colleagues drew data for their analysis from the National Ambulatory Medical Care Survey for the years 1990 through 1995. They report that the number of physician office visits nationwide resulting in a diagnosis of ADHD increased from 947,208 in 1990 to 2,357,833 in 1995.
The percentage of physician office visits resulting in a diagnosis of ADHD increased from 1.1 percent of all visits by this age group in 1990 to 2.8 percent by 1995. Over the same period, the rate of office visits resulting in a diagnosis of ADHD increased from 1.9 to 4.5 per 100 children in the age group.
Patients prescribed any type of stimulant medication for the treatment of ADHD increased from 1.2 to 3.4 per 100 U.S. children. Those prescribed Ritalin increased from 1.1 to 2.8 per 100 U.S. children.
Other researchers participating in the study were David A. Sclar, Tracy L. Skaer and Dr. Richard S. Galin, all with the Pharmacoeconomics and Pharmacoepidemiology Research Unit at WSU. Sclar is also a member of the research faculty at the Washington Institute for Mental Illness Research and Training. Galin is also affiliated with the University of California at Los Angeles Neuro-Psychiatric Institute.