Objectives: Most previous studies evaluating the use of methylphenidate following traumatic brain injury (TBI) have been conducted many years post-injury. This study evaluated the efficacy of methylphenidate in facilitating cognitive function in the inpatient rehabilitation phase.
Methods: 40 participants with moderate–severe TBI (mean 68 days post-injury) were recruited into a randomised, crossover, double blind, placebo controlled trial. Methylphenidate was administered at a dose of 0.3 mg/kg twice daily and lactose in identical capsules served as placebo. Methylphenidate and placebo administration was randomised in a crossover design across six sessions over a 2 week period. Primary efficacy outcomes were neuropsychological tests of attention.
Results: No participants were withdrawn because of side effects or adverse events. Methylphenidate significantly increased speed of information processing on the Symbol Digit Modalities Test (95% CI 0.30 to 2.95, Cohen’s d = 0.39, p = 0.02), Ruff 2 and 7 Test—Automatic Condition (95% CI 1.38 to 6.12, Cohen’s d = 0.51, p = 0.003), Simple Selective Attention Task (95% CI −58.35 to −17.43, Cohen’s d = 0.59, p = 0.001) and Dissimilar Compatible (95% CI −70.13 to −15.38, Cohen’s d = 0.51, p = 0.003) and Similar Compatible (95% CI −74.82 to −19.06, Cohen’s d = 0.55, p = 0.002) conditions of the Four Choice Reaction Time Task. Those with more severe injuries and slower baseline information processing speed demonstrated a greater drug response.
Conclusions: Methylphenidate enhances information processing speed in the inpatient rehabilitation phase following TBI.
This trial is registered with the Australian New Zealand Clinical Trials Registry (12607000503426).
Statistics from Altmetric.com
Funding: This study was supported by the Victorian Neurotrauma Initiative and the Wenkart Foundation, neither of which had any involvement in study design, analysis and interpretation of data, writing of the report or the decision to submit the article for publication. Drugs were purchased for the trial on a commercial basis, and the company that manufactures Ritalin made no contribution to the study.
Competing interests: None.
Ethics approval: Approval was obtained from Monash University and Epworth HealthCare ethics committees.