METHYLPHENIDATE PATTERNS AMONG MEDICAID YOUTHS

Treatment of attentional disorders in America has increased dramatical ly in recent years. This trend is accounted for partly by lengthening the duration of treatment into adulthood for some individuals as well as by increased treatment among girls. Beyond these factors, the role of economic status, race, and geographic region to explain the variati on in methylphenidate use is not well understood. Computerized adminis trative data were used to explore the influence of several sociodemogr aphic factors on the prevalence of methylphenidate use. The data sourc e consisted of Maryland Medicaid prescription drug reimbursement claim s data for FY1991 for children ages 5 to 14 years. In effect, the stud y was restricted to a sample of patients with limited income. The stud y aims included (1) measuring gender-, age-, race-, and region-specifi c methylphenidate prevalence for this restricted income population; (2 ) comparing the Caucasian:African-American (C:A-A) ratio for methylphe nidate with the C:A-A ratio for several drug therapies having non-psyc hotropic uses, specifically the anti-asthma drug, theophylline, and an tibiotics for infections; and (3) estimating the average daily dose of methylphenidate from prescription claims data. Total drug-specific pr evalence among the 5-14 year olds was 2.2 percent for methylphenidate while age-specific prevalence varied from 0.4 percent (5 year olds) to 3.4 percent (9 year olds). The gender ratio was 3.7:1 (M:F), confirmi ng the increasing trend for girls to receive this medication. Substant ial variation across eight defined regions of the state was observed. Racial differences were pronounced: African-Americans were 2.5 times l ess likely to receive methylphenidate than Caucasian youths. As hypoth esized, nonpsychotropic drug use was distinctly different from psychot ropic drug use in terms of race: theophylline was 1.5 times more likel y to be found for African-Americans than Caucasians, whereas antibioti c prescriptions were 1.5 times more likely to be prescribed to Caucasi an youths. Average daily dose of methylphenidate was estimated to be 1 8.7+/-10.4 mg for 5-9 year olds and 26.8+/-14.0 mg for 10-14 year olds . This brief report confirms the typically lower rate among African-Am erican Medicaid youths for most prescription drugs. The dramatic racia l disparity for the psychotropic agent methylphenidate is a new and co mpelling finding which should be verified among other economic groups. Diagnostic, referral, and cultural bias should be ruled out as possib le explanations for the observed differences.