Background: Blood pressure (BP) is the most important modifiable risk factor for cardiovascular (CV) disease and progression of kidney dysfunction in patients with chronic kidney disease. Despite extensive antihypertensive treatment possibilities, adequate control is notoriously hard to achieve. Several determinants have been identified which affect BP control. In the current analysis we evaluated differences in achieved BP and achievement of the BP goal between hospitals and explored possible explanations.
Methods: At baseline, BP was measured in a supine position with an oscillometric device in 788 patients participating in the MASTER PLAN study. We also retrieved the last measured office BP from the patient records. Additional baseline characteristics were derived from the study database. Univariate and multivariate analyses were performed with general linear modelling using hospital as a random factor.
Results: In univariate analysis, hospital was a determinant of the level of systolic and diastolic BP at baseline. Adjustment for patient, kidney disease, treatment or hospital characteristics affected the relation. Yet, in a fully adjusted model, differences between centres persisted with a range of 15 mmHg for systolic BP and 11 mmHg for diastolic BP.
Conclusion: Despite extensive adjustments, a clinically relevant, statistically significant difference between hospitals was found in standardised BP measurements at baseline of a randomised controlled study. We hypothesise that differences in the approach towards BP control exist at the physician level and that these explain the differences between hospitals.