Association of salivary dehydroepiandrosterone levels and symptoms in patients with attention deficit hyperactivity disorder during six months of treatment with methylphenidate.

This prospective study aimed to determine whether salivary levels of dehydroepiandrosterone (DHEA) in patients with attention deficit hyperactivity disorder (ADHD) change significantly during 6 months of treatment with methylphenidate (MPH), and to investigate long-term relationship between these levels and ADHD symptoms. Fifty ADHD patients aged between 6 and 12 years, and 50 age- and gender-matched healthy subjects were recruited. ADHD patients were prescribed oral MPH with a dose range of 5-15 mg/day at the discretion of the psychiatrist. DHEA levels were determined from saliva samples collected from both ADHD patients and healthy subjects at pretreatment and 1, 3, and 6 months from pretreatment visit. ADHD symptoms were evaluated with the Swanson, Nolan, and Pelham, Version IV Scale for ADHD and the ADHD Rating Scale, and computerized Continuous Performance Test (CPT). The results showed that salivary DHEA levels significantly increased in ADHD patients during the 6-month course of methylphenidate treatment, but the DHEA levels did not significantly change in the untreated healthy group during the 6-month period of natural observation. For the longitudinal observation, among ADHD patients, the salivary DHEA levels were independently correlated with distraction and impulsivity performance in the CPT, but not correlated with inattention and hyperactivity in the clinical ADHD symptoms. Whether DHEA exerts effects on neurocognitive functions as mediators or independently of MPH warrants further investigation.