Associations between Home, Office, and Central Blood Pressure and Microcirculatory Dysfunction in a Middle-Aged...

Hypertension is linked to endothelial dysfunction, but causality and direction is not entirely known. The aim was to study the cross-sectional associations between home, office, and central BP and microcirculatory peak oxygen saturation (OxyP).

In the observational Swedish CArdioPulmonary bioImage Study (SCAPIS) Linköping subsample, office and home BP were measured using an oscillometric device and OxyP was measured in forearm skin after a 5-min occlusion of the brachial artery. A linear regression was fitted to evaluate the mean change in OxyP per SD increase in BP. A logistic regression was fitted to evaluate the associations between BP above the median and OxyP below the median.

Of participants, 3,291 were included in the analyses. Per SD increase in systolic home BP, the adjusted mean (95% CI) difference in OxyP was -0.4 (-0.6 to -0.1%). In subgroup analyses, the association remained for women but not men, although the interaction by sex was not statistically significant. Also, in women but not in men, OxyP was lower in those with white coat hypertension vs. sustained normotension, i.e., mean (95% CI) 88.8 (88.2-89.4%) vs. 89.6 (89.3-90.0%), and in those with masked hypertension vs. sustained normotension, i.e., 87.5 (85.9-89.1%) vs. 89.6 (89.3-90.0%).

Home BP, which better predicts cardiovascular disease than office BP, was inversely associated with OxyP. This correlation remained in subgroup analyses of women but not men, suggesting possible sex-dependent microcirculatory dysfunction or that masked hypertension could be a more important cardiovascular risk marker in women, despite its higher prevalence in men.