Association between methylphenidate use and long-term cardiovascular risk in paediatric patients with attention deficit and hyperactivity disorder.

BACKGROUND: There have been concerns about the potential cardiovascular (CV) adverse effects associated with methylphenidate (MTH) use. However, only limited evidence exists on the long-term safety of MTH. OBJECTIVE: To evaluate whether MTH use is associated with long-term CV risk. METHODS: This was a retrospective cohort study using 2003-2017 data from the Health and Welfare Database in Taiwan. Patients newly diagnosed with attention deficit and hyperactivity disorder (ADHD) and between 3 and 18 years of age were included. Two treatment statuses were assessed: initial treatment ≥7 days and ≥180 days. Patients treated with MTH were compared with those receiving non-medication therapy. One-to-one propensity score matching was used to balance between-group differences. Study outcomes included major CV events, chronic CV disease, cardiogenic shock and all-cause mortality. Cox proportional hazard models were used to estimate HRs between the two groups. RESULTS: We began with 307 459 patients with ADHD. After exclusion, 224 732 patients were included in the final cohort. The results showed that compared with non-ADHD medication users, patients who were treated with MTH for more than 7 days had a similar risk of major CV events (HR 0.85, 95% CI 0.72 to 0.99; p=0.040). Identical trends were found in groups who were treated for more than 180 days (HR 0.83, 95% CI 0.69 to 1.00; p=0.050). The results of the sensitivity analyses were consistent with the main analyses across all groups and individual outcomes. CONCLUSION: Short-term MTH use did not increase CV risk among patients with ADHD. More evidence on long-term MTH use and risk of cardiogenic shock and death is warranted.

Prescribing patterns for attention deficit hyperactivity disorder among children and adolescents in Taiwan from 2004 to 2017.

This study documented the prescribing patterns of methylphenidate and atomoxetine among patients aged 3 to 18 in Taiwan diagnosed with attention deficit hyperactivity disorder (ADHD) between 2004 and 2017. Initial treatment for ADHD, the time between the first diagnosis and the first prescription, and medication-switching patterns were investigated. The final cohort consisted of 256,882 patients, and 147,210 (57.3%) of them received medication treatment. Most of the patients (98.2%) received methylphenidate. Atomoxetine use increased from 0.1% in 2007 to 5.5% in 2017. The median time between the ADHD diagnosis and the first prescription was 21 days (IQR: 0-212 days). In patients who initiated methylphenidate, 12,406 (8.4%) patients switched to atomoxetine; 850 (31.3%) of the children began with atomoxetine and switched to methylphenidate. In conclusion, methylphenidate was the predominant treatment for ADHD in 2004-2017. However, the prevalence of pharmacotherapy for ADHD was relatively low. Further investigation on the reasons behind this pattern is recommended.