Objectives: The purposes of this study were to determine whether salivary levels of dehydroepiandrosterone (DHEA) and cortisol are associated with attention deficit hyperactivity disorder (ADHD) or correlated with performance on the Continuous Performance Test (CPT).
Methods: Fifty ADHD patients and 50 age- and gender-matched controls aged between 6 and 12 years were included in this cross-sectional study. DHEA and cortisol levels were determined from saliva samples collected by the passive drool method at 08:00 h. ADHD patients subsequently performed a computerized Continuous Performance Test (CPT). ADHD symptoms were evaluated with the Swanson, Nolan, and Pelham, Version IV Scale for ADHD (SNAP-IV), completed by the patients' parents, and with the ADHD Rating Scale (ADHD-RS), administered by a child psychiatrist.
Results: Saliva DHEA levels and DHEA/cortisol ratios differed significantly between ADHD patients and controls. Among ADHD patients, saliva DHEA levels and DHEA/cortisol ratios were independently correlated with composite scores of CPT distractibility and CPT impulsivity. Basal levels of cortisol were not significantly associated with ADHD.
Conclusions: DHEA, but not the cortisol basal level, may be a biological laboratory marker for ADHD, particularly for performance on the CPT. Both the causal relationship between DHEA and ADHD and the role of DHEA in treating ADHD require further investigation.