Methylphenidate treatment of adult male prison inmates with attention-deficit hyperactivity disorder: randomised double-blind placebo-controlled trial with open-label extension

BACKGROUND: Attention-deficit hyperactivity disorder (ADHD) is highly prevalent in prison inmates, but pharmacological treatment has not yet been evaluated in this group. AIMS: To evaluate osmotic-release oral system (OROS) methylphenidate in adult male long-term prison inmates with ADHD. METHOD: Randomised, double-blind, placebo-controlled 5-week trial, followed by 47-week open-label extension in 30 prison inmates with ADHD and comorbid disorders. Primary outcome was level of ADHD symptoms after 5 weeks, evaluated by a masked assessor. Secondary outcomes were self-reported ADHD symptoms, global severity and global functioning throughout the 52-week trial, and post hoc treatment response and numbers needed to treat (NNT) (trial registration: NCT00482313.) RESULTS: Treatment significantly improved ADHD during the trial (P<0.001; Cohen's d = 2.17), with reduced symptom severity and improved global functioning. The placebo response, cardiovascular measures and adverse events were non-significant; the NNT was 1.1. Attention-deficit hyperactivity disorder symptoms, global severity and global functioning continued to improve during the open-label extension. CONCLUSIONS: Osmotic-release oral system methylphenidate is an effective treatment for adult male prison inmates with ADHD.