Post-concussion syndrome
Post-concussion syndrome, also known as postconcussive syndrome or PCS, is a set of symptoms that may continue for weeks, months, or a year or more after a concussion – a mild form of traumatic brain injury (TBI). The rates of PCS vary, but most studies report that about 15% of individuals with a history of a single concussion develop persistent symptoms associated with the injury. A diagnosis may be made when symptoms resulting from concussion last for more than three months after the injury. Loss of consciousness is not required for a diagnosis of concussion or post-concussion syndrome.
Post-concussion syndrome
PCS, which shares symptoms with a variety of other conditions, is highly likely to be misdiagnosed in people with these conditions. Cognitive and affective symptoms that occur following a traumatic injury may be attributed to mTBI, but in fact be due to another factor such as post-traumatic stress disorder, which is easily misdiagnosed as PCS and vice versa. Affective disorders such as depression have some symptoms that can mimic those of PCS and lead to a wrongful diagnosis of the latter; these include problems with concentration, emotional lability, anxiety, and sleep problems. Depression, which is highly common in persistent PCS, can worsen other PCS symptoms, such as headaches and problems with concentration, memory, and sleep. PCS also shares symptoms with chronic fatigue syndrome, fibromyalgia, and exposure to certain toxins. Traumatic brain injury may cause damage to the hypothalamus or the pituitary gland, and deficiencies of pituitary hormones (hypopituitarism) can cause similar symptoms to post-concussion syndrome; in these cases, symptoms can be treated by replacing any hormones that are deficient.