It’s easy enough to imagine that high blood pressure might cause headaches. You might think to yourself, “The heart beats strongly. The blood pushes against arterial walls. Maybe the skull begins to pound too, right?”
Not quite. As logical as that conclusion might seem, researchers have only seen evidence for this in very small, exceptional circumstances.
Read on to decode the real truths about the link between headaches and blood pressure.
People thought that headaches were a sign of high blood pressure a century ago. In 1913, eminent professor of medicine, Theodore C. Janeway reported in the Archives of Internal Medicine that early morning headaches appeared to be a symptom of high blood pressure.
Janeway, the first professor of medicine at Johns Hopkins University, wrote that a headache might appear in the patient at the same time as the onset of vascular disease. The headache might disappear after breakfast or as the day wore on, he stated.
But researchers today consider Janeway’s case studies misleading. Janeway’s patients had malignant hypertension, with a systolic pressure above 230. And one patient may have been taking excessive headache medication and experiencing analgesic rebound.
Later studies found no association between headache prevalence and high blood pressure, according to Norwegian headache researcher Knut Hagen in the Journal of Neurology, Neurosurgery and Psychiatry.
Still, patients and many doctors today continue to believe their blood pressure is high because they have a headache.
Neurologist Deborah Friedman notes several reasons for this viewpoint:
- Hypertension may be a phenomenon related to acute pain.
- Headache may be a side effect of some anti-hypertension medications.
- Conversely, pills to treat high blood pressure may prevent headaches, thus reducing the risk of headaches in treated patients.
Hagen’s research in Norway found that folks with hypertension might have fewer headaches. His team looked at more than 22,000 adults not likely to have headaches, measured at points in time 11 years apart.
Those with a systolic blood-pressure reading above 150 actually had a 30 percent lower risk of having a non-migraine headache. The systolic figure is the high or maximum number of the blood pressure reading. The researchers came up with hypalgesia—a term that refers to a diminished sensitivity to pain—as a possible explanation.
A headache may indeed be one of your symptoms if you have severe or “malignant” hypertension. This type of high blood pressure can come on very suddenly and affects about one percent of people with hypertension.
Malignant hypertension can affect younger adults, particularly African-American males. It can also affect patients with kidney problems and toxemia of pregnancy.
Signals of malignant hypertension headache include blurred vision and a change in mental status. You may also have nausea, weakness, shortness of breath, chest pain, or a seizure.
Malignant hypertension is a medical emergency. You need to be taken to a hospital, where you will receive medications intravenously to get your vitals under control.
The latest research indicates that regular tension headaches have little if any connection to hypertension. In fact, you are slightly less likely to have high blood pressure.
As for migraine headaches and high blood pressure, both are common disorders, which affect 10 to 22 percent of the adult population. Roughly three percent of the population can be expected to have both conditions.
Headache is not a reliable indicator except in cases of malignant hypertension. Your best bet is regular blood pressure testing.