My blood pressure reads differently in each arm — should I be concerned?

An inter-arm blood pressure difference of more than 10 mmHg systolic (consistently observed on repeat testing) warrants cardiovascular evaluation, because a persistent difference above 10 mmHg is associated with higher cardiovascular mortality, the mechanism involves subclavian artery stenosis or other structural vascular asymmetry that can indicate peripheral arterial disease, and should prompt an ABI (ankle-brachial index) and consideration of vascular imaging (Clark et al., Lancet, 201261227-4)).

Most men who find different readings in each arm have a minor technical discrepancy (different arm position, cuff placement) rather than structural vascular disease. The persistent pattern on proper measurement is the clinical signal. Inter-arm difference is often not checked in routine clinical practice, most blood pressure is measured in one arm only. For the 2–4% of men with significant inter-arm difference, it is one of the most missed cardiovascular findings in primary care.

Honesty Scale: Solid (1) for persistent inter-arm blood pressure difference as a cardiovascular signal.

What to do: Measure your blood pressure in both arms three times each, properly. If you consistently find a difference above 10 mmHg systolic, report it to your cardiologist. This is a legitimate finding that warrants vascular evaluation, not dismissal.

For the full picture, read The Blood Pressure Deep Dive