(245) Psychotropic Drug Utilization Patterns among Children and Adolescents in British Columbia, Canada: Sex Differences in Drug Initiation

Background: There is a lack of data on gender-specific psychotropic drug use in children and adolescents worldwide. A substantial risk of sex-bias exists in the diagnosis of psychiatric disease and the prescription of psychotropic drugs.

Objectives: To characterize the sex specific use of psychotropic drugs in children and adolescents and indication of use.

Methods: Study population: Children and adolescents (age: 0-19 years) in British Columbia (BC), Canada, with any psychotropic drug between 1997-2018. Data sources: BC health administrative databases: PharmaNet (prescription drug dispensing data); Medical Services Plan (physician visit data); and Discharge Abstracts (hospitalization data). Design and Analysis: Patient population was divided in four, five-year age groups (0-4, 5-9, 10-14, 15-19 years). Psychotropic drugs were assigned to seven drug classes. Drug initiation was defined as the first dispensing of a specific psychotropic drug for each child. Diagnostic codes most proximal prior to drug initiation were assessed and stratified by drug class, age and sex. ANOVA was used for continuous variables and Cochran-Armitage test for trend across age groups.

Results: 144,825 patients received at least one psychotropic drug. The number of patients who started their first ever psychotropic drug within each age group was fairly evenly distributed across the four age groups [median: 38,201; range 30,006 – 38,417]. However, the male/female ratio was subject to extreme change from 1.9 [age 5-9] to 0.6 [age 15–19] across age groups. We identified stimulant drugs as main drivers for the male predominance in elementary school children, while antidepressants were the most common drug class for female adolescents [age 15-19].
Assessment of the diagnostic codes proximal to drug dispensing, there was an even distribution of males and females across all age groups between psychiatric disease codes and prescribed drug classes. However, a major sex difference was found at the transitional age group from childhood to adolescence [age 10-14]. While in adolescents [15-19 years] the dispensing of antidepressants was equally associated with the diagnosis of depression [21.12% in males versus 21.43% in females], in the 10-14 year old age group only 9.97% of males [versus 19.01% of females] received the diagnosis of depression. Instead, 14.16% of males had the diagnosis of ADHD at drug initiation with antidepressants [versus 4.33% in females].

Conclusions: These results indicate, that a proportion of boys diagnosed with ADHD between 10-14 years of age may have a depressive disorder but not recognized as such until late adolescence. We suggest that clinicians should carefully diagnose ADHD and monitor stimulant drug use in male children at the transition between childhood and adolescence.