"Myxedema madness" associated with newly diagnosed hypothyroidism and obstructive sleep apnea

This is the case report of a 32-year-old obese male with a history of agitation, hallucinations, and delirium, recently diagnosed with primary hypothyroidism; he gave a several month history of fatigue with nocturnal snoring and frequent awakening. Polysomnogram revealed severe OSA; initiation of CPAP and levothyroxine resulted in immediate improvement. The lack of a previous psychiatric history and acuteness of presentation was consistent with hypothyroid psychosis complicated by sleep deprivation cause by untreated OSA. Primary hypothyroidism is a common disorder often associated with depression. It is rarely associated with psychosis and was first described as "myxoedematous madness" in 1949. It has not been previously reported to cause psychosis when associated with obstructive sleep apnea. This case illustrates the need for examination of potential multiple organic causes in a patient who presents with psychosis in the critical care setting.