Improper arm positioning may inflate NHS blood pressure readings, risking misdiagnosis

A GP has cautioned that simple errors in arm positioning during routine NHS blood pressure checks may produce inflated readings, leading to misdiagnosis and unnecessary medication. NHS guidelines advise patients sit upright with the arm supported at heart level, but busy clinics often neglect this practice. Research from Johns Hopkins Medicine found that a hanging arm can increase systolic pressure by nearly 7 mmHg, while a lap-rested arm adds about 4 mmHg.

Such differences can push readings over diagnostic thresholds, prompting unwarranted treatment and potential side-effects. High blood pressure affects roughly one in three adults in England and often goes unnoticed until serious complications arise. The findings echo earlier UK research indicating many hypertensive patients are unaware of their condition and that treatment control rates are low.