title: Urine Toxicology in Adults Evaluated for a Central Hypersomnia and How the Results Modify the Physician's Diagnosis.
abstract: Drugs and psychoactive substances can cause sleepiness and when undetected, may lead to over diagnosis of central hypersomnias. We performed urine drug testing using gas chromatography-mass spectrometry in adults undergoing multiple sleep latency testing (MSLT) for a suspected central hypersomnia. We examined how the drug test results modified the treating physician's diagnosis.
  
  
  
  One hundred eighty-six consecutive patients with a suspected central hypersomnia who underwent clinical assessment, MSLT and urine drug testing by gas chromatography-mass spectrometry were retrospectively studied. Physicians made a diagnosis after clinical assessment and MSLT and were initially blinded to the urine drug test results.
  
  
  
  A third of patients assessed for subjective hypersomnia had a positive urine drug test for a substance affecting sleep. Opioids, cannabis, and amphetamines were the commonest drugs detected. Using MSLT, 35 (18.8%) of 186 patients had objective hypersomnia that may have been due to a drug or substance. Drugs or substances may have confounded the MSLT in 11 (20.1%) of 53 patients who fulfilled diagnostic criteria for idiopathic hypersomnia, and 12 (52%) of 23 of those who fulfilled diagnostic criteria for narcolepsy without cataplexy. Of the 75 positive urine drug samples, 61 (81%) were substances or medications not revealed in the physician interview. The treating physician had not suspected drugs or substances as a possible cause of objective hypersomnia in 34 (97%) of the 35 patients.
  
  
  
  Drugs and psychoactive substances can confound the results of the MSLT and when undetected could lead to over diagnosis of central hypersomnias.
authors: West Australian Sleep Disorders Research Institute, Sir Charles Gairdner Hospital, Perth, Western Australia.|Sleep Disorders Centre Guys' Hospital, London, UK.
authors: Christopher A
authors: CA
authors: Kosky
authors: Sleep Disorders Centre Guys' Hospital, London, UK.|National and Kapodistrian University of Athens, 2nd Neurological Unit, Attiko Hospital, Greece.
authors: Anastasios
authors: A
authors: Bonakis
authors: West Australian Sleep Disorders Research Institute, Sir Charles Gairdner Hospital, Perth, Western Australia.|Sleep Disorders Centre Guys' Hospital, London, UK.
authors: Arthee
authors: A
authors: Yogendran
authors: Sleep Disorders Centre Guys' Hospital, London, UK.|Medway Maritime Hospital, Gillingham, UK.
authors: Gihan
authors: G
authors: Hettiarachchi
authors: Clinical Toxicology, Guy's and St Thomas' Foundation Trust, London, UK.|Faculty of Life Sciences and Medicine, King's College London, United Kingdom.
authors: Paul I
authors: PI
authors: Dargan
authors: Sleep Disorders Centre Guys' Hospital, London, UK.
authors: Adrian J
authors: AJ
authors: Williams
mesh_terms: D000328:Adult; D003937:Diagnosis, Differential; D006970:Disorders of Excessive Somnolence / Q000209:etiology*; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D008297:Male; D012189:Retrospective Studies; D019966:Substance-Related Disorders / Q000150:complications* / Q000652:urine*
keywords: adults; amphetamines; cannabis; disorders of excessive somnolence; gas chromatography-mass spectrometry; hypersomnolence; idiopathic; narcolepsy; opioid; polysomnography