Abstract
OBJECTIVE: This study examined the association between race-ethnicity and patterns of medication gaps and discontinuities among Medicaid-insured children initiating pharmacotherapy for attention-deficit hyperactivity disorder (ADHD). METHODS: Medicaid claims data from nine states were used to identify racial-ethnic differences in patterns of ADHD medication treatment among 102,669 children initiating ADHD medication. Multinomial logistic regression with state indicators was used to estimate these differences, with adjustment for individual and contextual confounders. RESULTS: Approximately three-fifths of the sample did not receive continuous medication treatment as defined by HEDIS guidelines; among them, one-fifth discontinued treatment with no subsequent reinitiation (early termination), less than one-tenth reinitiated pharmacotherapy following a single medication gap, more than three-tenths experienced discontinuous pharmacotherapy with two gaps, and more than four-tenths experienced discontinuous pharmacotherapy with three or more gaps. Compared with white children, black children had a 25% relative increase in the likelihood of early termination and Hispanic children had a 21% relative increase (p<.001); their relative increases in the likelihood of two medication gaps were 41% and 29%, respectively (p<.001), and for three or more gaps they were 56% and 40%, respectively (p<.001). CONCLUSIONS: Black and Hispanic children were much more likely than white children to be classified as discontinuing ADHD medication treatment, according to HEDIS. The differences predominantly occurred because youths from minority groups were more likely to experience multiple medication gaps, rather than complete discontinuation. Future studies should examine reasons for these multiple gaps to inform interventions to improve ADHD treatment continuity.