The "Hypertensive Headache"
Approximately 25 percent of adults in the United States suffer from high blood pressure, also called hypertension. A century ago, this was commonly associated by the medical profession with headaches, a view that widely persists among the public today. More recently, a number of studies have begun to chip away at this time-honored idea, and more recently even to stand it on its head. High blood pressure can cause many unpleasant symptoms, including but not limited to pain in many bodily areas, vision problems, constipation, cough, vomiting, diarrhea, dizziness, pain and swelling in the legs and feet, heart palpitations, nausea, numbness in the extremities, shortness of breath and difficulty with urination. Headache is also listed on the Mayo Clinic website as a possible symptom of hypertension, yet headache is a very common condition and can exist in hypertensive patients as a result of unrelated medical problems or stress.
Changing Perceptions
A 1953 report by one physician observing his patients found that almost three-quarters of people with high blood pressure who knew of their condition suffered from headaches, while only 16 percent of hypertensives unaware of their disease reported headaches. This data led the physician to attribute many of the headaches to worry or stress. Almost a decade later, a U.S. study called the Health Examination Survey of Adults (NHANES) found no statistical correlation between high blood pressure and headaches. Some later studies claimed to find a faint correlation between high blood pressure and headaches, but no consensus to this effect developed in the health care community. In recent years, the morning headaches suffered by many hypertensive patients have been attributed to sleep apnea and other breathing disorders that can be associated with high blood pressure.
The Modern View
A study conducted at Trondheim University Hospital in Norway and reported in 2008 in the journal "Neurology" found no connection between high blood pressure and headaches, and in fact suggested that people suffering from hypertension may have fewer headaches than others as a result of the condition. The study, which was undertaken during two different time periods, examined the health data of over 50,000 Norwegians. (Only ordinary headaches, and not migraines, were considered.) According to the Trondheim study, one significant factor affecting headaches was found to be systolic pressure, the upper number of the blood pressure reading. Headaches in patients with high systolic pressure tended to occur more rarely. Even more telling was a correlation with the "pulse pressure," which describes the difference between systolic and diastolic pressure as the heart beats. The incidence of headaches in patients with high pulse pressure proved to be reduced by as much as half. When hypertensive patients in the study took medicine to treat the condition, headaches tended to become more frequent. One possible explanation that has been advanced is that hypertension sufferers typically develop stiffer arterial walls, reducing headache pain.
