Can hypertension cause headaches?

Can Hypertension Cause Headaches?

Hypertension typically does not cause headaches except in cases of severely elevated blood pressure such as hypertensive emergencies or hypertensive encephalopathy. 1

Relationship Between Hypertension and Headaches

Mild to Moderate Hypertension

• Mild (140-159/90-99 mmHg) or moderate (160-179/100-109 mmHg) chronic arterial hypertension does not appear to cause headaches 2
• Multiple studies have shown no convincing relationship between blood pressure fluctuations over a 24-hour period and the presence or absence of headache in patients with mild to moderate hypertension 3, 4
• Ambulatory blood pressure monitoring has demonstrated that headache episodes in patients with mild hypertension are generally not associated with simultaneous blood pressure elevations 4

Severe Hypertension and Headaches

• Headaches are associated with disorders that lead to abrupt, severe, and paroxysmal elevations in blood pressure 2
• Headache is recognized as a symptom of hypertensive emergencies and is listed among the "Symptoms/Signs of Hypertension/Coexistent Illnesses" in international guidelines 5
• Hypertensive encephalopathy, a dangerous condition with severely elevated blood pressure, commonly presents with headache along with other neurological symptoms 1

Clinical Scenarios Where Hypertension May Cause Headaches

Hypertensive Emergencies

• In hypertensive emergencies (BP ≥180/120 mmHg with evidence of impending or progressive target organ dysfunction), headache may be present 5
• Hypertensive encephalopathy presents with symptoms including headache, somnolence, lethargy, tonic-clonic seizures, and cortical blindness 5

Secondary Causes of Hypertension

• Certain conditions causing secondary hypertension may present with headache:
  • Pheochromocytoma - characterized by paroxysmal hypertension and headaches 2
  • Pre-eclampsia and eclampsia - hypertension in pregnancy with headache as a warning sign 2

Important Clinical Considerations

Diagnostic Approach

• When a patient presents with both headache and hypertension, do not automatically attribute the headache to the elevated blood pressure unless BP is severely elevated (hypertensive emergency) 4
• Look for other causes of headache in patients with mild to moderate hypertension 3
• Consider MRI with FLAIR imaging if hypertensive encephalopathy is suspected 5

Treatment Implications

• Treating hypertension may reduce headache frequency in some patients, but this is likely due to other mechanisms rather than direct BP-headache correlation 6
• Calcium channel blockers appear most likely to cause headache as a side effect in patients taking antihypertensive medications 1, 6
• For patients with both migraine and hypertension, consider medications that may treat both conditions, such as angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers 7

Bottom Line

Headache should not be attributed to hypertension unless blood pressure is severely elevated (hypertensive emergency) or there is evidence of hypertensive encephalopathy. In routine clinical practice, mild to moderate hypertension is not a cause of headache, and other etiologies should be investigated when patients with hypertension present with headache.