Vitals by Age

Vital signs are read against fixed category thresholds, not against a laboratory reference interval. That distinction runs through everything in this section.

A lab reference range comes from the distribution of results in a reference population and differs between laboratories. A blood pressure category comes from a guideline committee that drew lines where outcome data supported drawing them. The first describes what is common; the second describes what is advisable.

Blood pressure has no separate target by age

The 2017 ACC/AHA guideline gives one set of categories for all adults: normal under 120/80, elevated 120–129 with diastolic under 80, stage 1 at 130–139 or 80–89, stage 2 at 140 or higher or 90 or higher.

A great deal of material online still prints a higher "normal" for older adults. Those are descriptive averages — blood pressure does rise with age as arteries stiffen — and publishing an average as a target turns a description of what happens into a permission slip. The 2017 guideline moved the threshold down for all adults precisely because the outcome data did not support the older, more permissive figure.

Note the operator: "or", not "and", from stage 1 downward. A reading of 135/75 is stage 1 on the systolic number alone.

Heart rate does vary with age

Unlike blood pressure. A resting rate of 60 to 100 covers healthy adults of any age, but children run considerably faster — a newborn at 100 to 160 is normal and would be a concern in an adult.

Trained endurance athletes commonly sit in the 40s, which is a sign of conditioning rather than a problem.

One reading is not a diagnosis

Blood pressure varies through the day by 10 to 20 mmHg and rises with a full bladder, recent caffeine, a conversation, and the walk in from the car park. A diagnosis rests on an average of two or more readings on two or more separate occasions.

Home readings taken calmly are often more representative than clinic ones. White coat hypertension is common enough to be a named phenomenon, and so is its opposite.

The measurement technique changes the number more than most people expect

Cuff size is the largest single source of error — a cuff too small reads high, sometimes by 10 to 40 mmHg. An unsupported arm reads high. Talking during the measurement reads high. Sitting quietly for five minutes first is not a formality.

Sources: 2017 ACC/AHA Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults; American Heart Association Understanding Blood Pressure Readings.

This section reproduces published clinical reference ranges for general information. It is not medical advice, it cannot account for your history or medication, and it does not replace a clinician.