For people who had high blood pressure readings only while sitting (normal readings while lying down), there was no statistically significant difference in the 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 people with high readings while lying down) and an 11 percent higher risk of all-cause mortality.
(In this study, high blood pressure readings for either position were defined as those with systolic readings (the top number) of 130 mm Hg or higher or diastolic readings (the bottom number) of 80 mm Hg or higher.)
The people with the highest risks across the board were those who had high blood pressure readings both while sitting and lying down.
“These findings suggest that measuring in the supine position [lying down] BP may be useful for identifying elevated blood pressure and latent CVD risk,” the researchers concluded.
Strengths and hypotheses
For now, the findings should be considered preliminary. Such analysis and finding needs to be repeated with another group of people to confirm the connection. And as for the larger question of whether using medications to lower supine blood pressure (rather than sitting blood pressure) is more effective at reducing risk, it's likely that clinical trials will be needed.
Still, the analysis had some notable strengths that make the findings worthwhile. The size and design of the study are robust. Researchers used data from the Atherosclerosis Risk in Communities (ARIC) study, a survey conducted in 1987 among middle-aged people living in one of four U.S. communities (Forsyth County, North Carolina; Jackson, Mississippi; the suburbs of Minneapolis, Minnesota and Washington). County, Maryland).
