II. Epidemiology: Prevalence
- Episodic Headaches: 50% of U.S. adults suffer from Headaches at any period of time
- Progress to chronic Headaches in 3-4% of episodic Headache patients (Central Sensitization)
- Chronic Headaches: 2-4% of U.S. Adults
- Chronic daily symptoms in up to 30% of those with chronic Headaches
-
Headaches are a common trigger for medical care visits
- Acute Headache is the fourth most common reason for Emergency Department evaluation
- Half of Migraine Headache visits are to primary care
III. Pathophysiology: Headache Central Sensitization
- Frequent episodic Headaches may progress to chronic Headaches without management
- Results in Central Sensitization and Neuronal dysfunction
-
Central Sensitization Inappropriate response to low level stimuli
- Lower thresholds trigger pain response
- Exaggerated stimulus response
- Pain persists after trigger is removed
- Risk Factors for progression from episodic Headache to chronic Headache are specific to Headache type
IV. Causes: Primary Headaches
- See Acute Recurrent Headache
- See Chronic Nonprogressive Headache
- Common Primary Headaches
- Tension Headache (50% of acute Headaches)
- Common Migraine Headache (10% of acute Headaches)
- Other Primary Headaches
- Migraine with Aura (Classic Migraine)
- Cluster Headache and other trigeminal autonomic Cephalgias (<1%)
- Sexual Headache
V. Causes: Secondary Headaches
- See Headache Red Flag
-
Acute Localized Headache
- Sinus Headache (e.g. Acute Sinusitis)
- Myofacial pain
- Ophthalmologic Headache
- Acute Angle-Closure Glaucoma (severe Eye Pain)
- Generalized Headache
- Urgent or Life-treatening secondary causes with possible positive Head CT
- Urgent or Life-treatening secondary causes with negative Head CT
- Acute angle closure Glaucoma
- Bacterial Meningitis or Encephalitis
- Carbon Monoxide Poisoning
- Temporal Arteritis (Giant Cell Arteritis)
- Cerebral or dural venous sinus thrombosis
- Cavernous Sinus Thrombosis
- Cervical Artery Dissection (carotid dissection, Vertebrobasilar Dissection)
- Preeclampsia or Eclampsia (Pregnancy Induced Hypertension)
- Pituitary Apoplexy
- Hypertensive Emergency
- Reversible Cerebral Vasoconstriction Syndrome (RCVS)
- Miscellaneous secondary causes
VI. History
- See Headache History
VII. Exam
VIII. Differential Diagnosis
- See Headache Causes
- See Headache Red Flag
- See Organic Headache
IX. Diagnostics
X. Management
- See Nonpharmacologic Headache Treatment
- See Chronic Daily Headache
- Musculoskeletal Headaches
- Migraine Headache Management
- Iatrogenic Headaches and medication overuse
- Trigeminal Nerve Syndromes
- Organic Headaches
- Headache Management in women
-
Headaches in other specific cohorts
- See Headache in HIV
XI. References
- Ramdhan (2023) Crit Dec Emerg Med 37(5): 23-9
- Mayans (2018) Am Fam Physician 97(4): 243-51 [PubMed]
- Walling (2020) Am Fam Physician 101(7):419-28 [PubMed]
- Viera (2022) Am Fam Physician 106(3): 260-8 [PubMed]