Background/aims: Although several guidelines propose two or three measurements of home blood pressure (HBP) on each occasion, the actual status of multiple measurements is not clear in the practical management of hypertension. We surveyed the details regarding two measurements of HBP in patients with chronic kidney disease (CKD).
Methods: HBP was measured twice every morning and evening over 7 consecutive days in 175 CKD patients. The distribution of the differences between two BP values (2nd - 1st BP) and their association with BP parameters were evaluated.
Results: The 2nd - 1st morning systolic BP (SBP) and diastolic BP (DBP) differences were -2.3 ± 4.1 and -0.4 ± 2.6 mm Hg, respectively. The proportion of 2nd - 1st morning SBP differences >0 mm Hg was 31.7% in a total of 1,195 measurements. Eighty patients (45.7%) had days with a difference ≤-5 mm Hg and days with a difference ≥5 mm Hg in morning SBP during 7 days. The multivariate regression analysis of the SD values of 2nd - 1st morning SBP as a dependent variable showed that the SD value of the 1st morning SBP (β = 0.65, p < 0.001) was a significant determinant.
Conclusion: Although the 2nd SBP was 2-3 mm Hg lower than the 1st SBP in the population as a whole, various differences were found for each subject during 7 days. 2nd - 1st BP variability might be associated with day-by-day 1st BP variability.
Keywords: Blood pressure variability; Chronic kidney disease; Home blood pressure; Hypertension; Self-measurement of blood pressure.