Post-traumatic headache (PTH) is a common and debilitating consequence of mild traumatic brain injury (mTBI) that can occur over one year after the head impact event. Thus, better understanding of the underlying pathophysiology and risk factors could facilitate early identification and management of PTH. There are several factors that could influence the reporting of PTH prevalence, including the definition of concussion and PTH. The main risk factors for PTHs include a history of migraines or headaches, female gender, younger age, greater severity of the head injury, and co-occurring psychological symptoms, such as anxiety and depression.
Pathophysiology Features | Description |
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Impaired descending pain modulation [5] | Abnormalities in the central nervous system’s pain control system leading to an increase in pain sensitivity. |
Neurometabolic changes [5] | Changes in the brain’s metabolic activity, including an increase in lactate and a decrease in glucose metabolism, leading to a cascade of neuroinflammatory events. |
Neuroinflammation [5] | A response to the injury that leads to an increase in pro-inflammatory cytokines and chemokines and activation of microglia and astrocytes. |
Cortical spreading depression [5] | A wave of depolarization that spreads across the cortex leading to the release of inflammatory molecules and a decrease in cerebral blood flow. |
Release of calcitonin gene-related peptide (CGRP) [5] | A neuropeptide that may mediate trigeminovascular pain transmission and trigger a migraine attack. |
Trigeminal system activation [5] | Activation of the trigeminal nerve, which is implicated in migraine and other primary headache disorders. |
Secondary cascade of metabolic and cellular excitotoxic and inflammatory changes [6] | TBI can lead to a secondary cascade of events that can promote the development of PTH. |
Hypersensitivity to CGRP [9,11][9][11] | Patients with PTH who have no prior history of migraine exhibit hypersensitivity to CGRP. |
Erenumab treatment [10] | A CGRP receptor antagonist that has been shown to reduce the number of days with moderate or severe headache in patients with PTH. |