What Clinicians Might Miss in ADHD: Sleep Disorders, Comorbidities, and a Link to Depression

Ann Childress, MD, discussed the importance of sleep assessment in the evaluation of attention-deficit hyperactivity disorder (ADHD), the underrecognition of executive dysfunction and emotional dysregulation as core ADHD features, and the clinical consequences of undiagnosed ADHD masquerading as treatment-resistant depression (TRD). Childress presented on ADHD therapies and insomnia management at the 2026 Southern California Psychiatry conference.

Childress emphasized that sleep assessment should be a routine component of every ADHD evaluation. She noted that sleep deprivation alone can produce inattention, hyperactivity, and emotional dysregulation that mimic ADHD—and that in some patients, the underlying diagnosis is a sleep disorder rather than ADHD. She highlighted obstructive sleep apnea in children as a particularly important example, noting that enlarged tonsils are a common cause. She cited data indicating that tonsillectomy and adenoidectomy in children with obstructive sleep apnea results in resolution of ADHD-like behaviors in approximately 2 out of 3 to 80% of cases, underscoring the clinical importance of distinguishing primary ADHD from sleep-disorder-driven behavioral symptoms before initiating stimulant therapy.

Childress also addressed the broader challenge of evaluating ADHD in its full clinical complexity. She argued that clinicians are skilled at identifying core symptoms (inattention, hyperactivity, and impulsivity) but frequently underweigh executive dysfunction, emotional dysregulation, and psychiatric comorbidities in their assessments. She emphasized that undiagnosed ADHD can present as and be mistakenly treated as other psychiatric disorders, including TRD. Childress cited the work of Martin Katzman, MD, whose study of patients referred to his clinic for TRD found that approximately 34% had previously undiagnosed ADHD, and stressed that depression and ADHD require different treatment approaches.¹ She added that ADHD can drive apparent treatment resistance, even when multiple antidepressant trials have been attempted—a diagnostic consideration she noted is frequently overlooked.²

Dr Childress is a child, adolescent, and adult psychiatrist, president of the Center for Psychiatry and Behavioral Medicine in Las Vegas, Nevada, and past president of the American Professional Society of ADHD and Related Disorders.

References

1. Sternat T, Fotinos K, Fine A, et al. Low hedonic tone and attention-deficit hyperactivity disorder: risk factors for treatment resistance in depressed adults. Neuropsychiatr Dis Treat. 2018;14:2379–2387.

2. Katzman MA, Bilkey TS, Chokka PR, et al. Adult ADHD and comorbid disorders: clinical implications of a dimensional approach. BMC Psychiatry. 2017;17(1):302.