A 10- to 12-year-old white boy who lives in a predominantly white, higher-income area in Louisiana with only one or two siblings and is covered by commercial insurance is much more likely than most children in the United States to receive a prescription for a stimulant medication for attention-deficit/hyperactivity disorder (ADHD). If a child with ADHD doesn’t quite fit that stereotypical mold, the chances of receiving appropriate medication therapy are not quite as good.
"This is an extremely helpful study," said David Fassler, M.D., APA trustee-at-large and a member of the governing council of the American Academy of Child and Adolescent Psychiatry (AACAP). "It confirms our clinical impression that practice patterns vary considerably across the country."
Indeed, AACAP has been concerned about variations in stimulant use for some time and in late 2001 approved a new practice parameter on the use of stimulants to treat ADHD in children and adolescents (Psychiatric News, April 19, 2002). The parameter was published in the February 2002 supplement of the Journal of the American Academy of Child and Adolescent Psychiatry.
Cox reported that about 65 percent of all stimulant claims reviewed were for methylphenidate (Novartis’s Focalin, Ritalin, and Ritalin LA; ALZA’s Concerta; and Celltech’s Metadate CD/ER; as well as numerous generics), about one-third of claims were for amphetamines (GlaxoSmithKline’s Dexedrine, Shire’s Adderall and Adderall XR, and certain generics), and less than 2 percent were for pemoline (Abbott’s Cylert and generics).
Over the entire sample, 4.3 percent of the 178,800 children had at least one claim for a stimulant between January 1 and December 31, 1999. Prevalence of use increased as a function of age in both boys and girls, with peak use occurring around 11 years of age. However, the researchers noted that there was "only a slight decrease in use at age 14. These findings are consistent with the growing awareness of the chronic nature of ADHD and its persistence into adolescence."
Research in the 1980s had suggested that boys were as much as eight times more likely than girls to receive prescriptions for stimulants; however, more recent reports in the 1990s showed a narrowing gender gap, closer to 5 to 1. Cox and her colleagues support that notion, reporting a gender gap of 2.6 to 3.8 prescriptions for boys to each prescription for a girl.
Lois Flaherty, M.D., chair of APA’s Council on Children, Adolescents, and Their Families and a child and adolescent psychiatrist in Boston, believes these results may reflect growing awareness of the realities of the disorder.
"These findings seem to reflect much of what has been learned over the past couple of decades," Flaherty told Psychiatric News. "ADHD tends to be persistent, and girls tend to have the inattentive subtype. Stimulants unquestionably are effective in reducing symptoms."
Even after controlling for gender and age, however, Cox found that geographic variation in the use of stimulants still was significant. Prevalence rates ranged from a low of 1.6 in the District of Columbia to a high of 6.5 in Louisiana (expressed as the number of children receiving at least one stimulant prescription during the study period per 100 insured children). More generally, children living in Southern states were 1.7 times more likely than those in Western states to have a prescription claim for a stimulant. Children in the Midwest were 1.55 times more likely than those in the West. However, no significant difference was seen between the West and the Northeast.
"This is surprising, in that the areas with the highest rates of stimulant prescriptions are not those with the highest physician concentrations," Flaherty commented. "These regional differences could be due to different thresholds for making the diagnosis, as well as different attitudes toward treatment on the part of physicians as well as families."
One of the study’s most intriguing findings is that children in larger families (with four or more children) were 26 percent less likely to have a claim for at least one stimulant medication.
Also, children in more-affluent families were more likely to receive a stimulant than those in lower-income areas. Flaherty said that finding is certainly consistent with her own clinical experience and believes that an increased awareness on the part of affluent families could be a factor, as well as less stigma being attached to ADHD in those communities.
"But there is also the possible factor of more pressures on these children to succeed in school and concerns that a child with attention problems may be at a disadvantage academically," she noted.
Both Fassler and Flaherty believe the study is significant and raises many appropriate questions, although Cox and her colleagues were careful to note the study’s limitations and emphasize that the study "did not attempt to determine if the higher rates of use represent overuse, or the lower rates of use represent underuse, although we believe, as has been reported in other studies, that both may be occurring. Future research should explore the reasons for this variation."
"We do know," Flaherty commented, "that psychiatrists do not write the majority of prescriptions for stimulants. Primary care physicians are struggling with how to evaluate children properly given the constraints in time and funding they have to deal with. Often psychiatrists in managed care settings are expected to make the diagnosis in one evaluation setting—which certainly does not allow for the kind of comprehensive evaluation that is proposed by the AACAP and more recently by the American Academy of Pediatrics as the standard of care."
Fassler noted that the variations are partly a result of the presence or absence of parity legislation in different states, differing levels of access to comprehensive services, as well as issues of stigma, media coverage, and awareness by and education of primary care physicians.
"The real tragedy," Fassler said, "is that so many children across the country are still not receiving the comprehensive evaluation and treatment that they both need and deserve."
An abstract of "Geographic Variation in the Prevalence of Stimulant Medication Use Among Children 5 to 14 Years Old: Results From a Commercially Insured U.S. Sample" is posted on the Web at www.pediatrics.org/cgi/content/abstract/111/2/237. The AACAP practice parameter is available to AACAP members free at http://office.aacap.org/eseries/ScriptContent/Index.cfm. Ordering information is available at www.aacap.org/publications/pubcat/guideline.htm or by phone at (800) 333-7636, ext.131. ▪