What does my blood pressure say about my long-term health?
A structurally high or strongly fluctuating blood pressure substantially increases your risk of stroke, heart attack and premature death. Small adjustments such as eating less salt and measuring regularly make a demonstrable difference.
Of all the values your doctor checks, your blood pressure probably says the most about your long-term health. High blood pressure is the single most important modifiable risk factor for stroke. That lowering blood pressure genuinely helps has been robustly demonstrated in large studies1.
A single reading at the doctor's office tells only part of the story. How long your blood pressure has been elevated matters more than any one snapshot. A cohort study in people aged 45 and older showed that each additional unit of accumulated blood pressure burden increased the risk of cardiovascular disease by 12% and the risk of stroke by 35%2. Fluctuations also count: blood pressure that is low one time and high the next raises your risk of death and cardiovascular problems. That effect is comparable to that of excessively high cholesterol3.
Some people maintain high blood pressure despite taking three or more blood-pressure-lowering medications at maximum doses. This is called resistant hypertension. It affects roughly one in six people with high blood pressure and is associated with considerably higher chances of a heart attack, stroke, heart failure and kidney disease. Early recognition and adjustment of treatment are especially important here4.
Salt restriction is one of the best-supported things you can do yourself. Eating less salt, on average 4.4 grams less per day, already produced a measurable drop in blood pressure after just four weeks. In people who already had high blood pressure the effect was even greater. This is a proven causal relationship5.
High blood pressure is not purely an adult problem. Due to rising obesity, doctors are seeing it more and more often in children and teenagers, while it frequently goes unrecognised in that age group6. Home measurement combined with telephone coaching led to an additional blood pressure reduction of 8.1 mmHg in a study of stroke patients. After 24 months, however, this did not result in a demonstrably lower number of new strokes7. Home measurement therefore helps with regulation itself, but whether it actually leads to fewer cardiovascular events has not yet been proven.
The claims are based on meta-analyses (salt reduction, blood pressure fluctuation), cohort studies (cumulative blood pressure) and a randomised trial (home monitoring). The strength of evidence ranges from strong (stroke, salt) to moderate (fluctuation, resistant hypertension) to limited (children). Causal relationships are most strongly established for salt reduction and stroke risk.