For real, we may be taking blood pressure readings all wrong

For people who had high blood pressure readings only when sitting (normal readings while lying down), there was no statistically significant difference in risk of coronary heart disease, heart failure, or stroke compared to people with normal blood pressure. The only statistically significant differences were a 41 percent higher risk of fatal coronary heart disease (compared to the 78 percent seen in those with high readings lying down) and an 11 percent higher risk of all-cause mortality.

(In this study, high blood pressure readings were defined for both positions as those with systolic readings (the top number) of 130 mm Hg or greater or diastolic readings (the bottom number) of 80 mm Hg or greater.)

The people with the highest risks across the board were those who had high blood pressure readings while both sitting and lying down.

“These findings suggest that measuring supine [lying down] BP may be useful for identifying elevated BP and latent CVD risk,” the researchers conclude.

Strengths and hypotheses

For now, the findings should be considered preliminary. Such an analysis and finding should be repeated with a different group of people to confirm the link. And as to the bigger question of whether using medication to lower supine blood pressure (rather than seated blood pressure) is more effective at reducing risk, it’s likely that clinical trials will be necessary.

Still, the analysis had some notable strengths that make the findings attention-worthy. The study’s size and design are robust. Researchers tapped into data from the Atherosclerosis Risk in Communities (ARIC) study, a study established in 1987 with middle-aged people living in one of four US communities (Forsyth County, North Carolina; Jackson, Mississippi; suburban Minneapolis, Minnesota; and Washington County, Maryland).