This is an age old question that many of us have struggled with in the ED for many years...
Other questions include: Does elevated BP cause headaches? Do we need to scan hypertensive patients with headache just because they have a headache? At what level of BP does the BP actually cause headache?
A few quick pearls:
Although incredibly high BPs (diastolics above 130 mm Hg) have been correlated with headache, the general concensus is that hypertension doesn't really cause headaches.
At really high blood pressures (again, diastolic BP > 130-140), cerebral autoregulation breaks down and may lead to cerebral edema and headache...hypertensive encephalopathy.
Elevated systolic BP may actually be protective for developing headaches
CT scanning the hypertensive patient with a headache is not warranted a lot of the time, unless the patient has a neuro deficit, or if the headache was acute onset or associated with other findings of hypertensive encephalopathy.
Patients with HTN are as likely to have a headache in the ED as non-hypertensive patients
