Optimal indicators of home BP variability in perimenopausal women and associations with albuminuria and reproducibility: The J-HOT home BP study

Background This study investigated the associations between various indicators of home blood pressure (BP) variability and albuminuria as well as the reproducibility of these indicators in perimenopausal women, who are likely to exhibit increased BP variability. Methods As a measure of organ damage, urinary albumin/creatinine ratio (UACR) was examined at baseline in 151 women aged 40-59 years. Home BP was measured in duplicate in both morning and evening for 12 weeks using a home BP monitor. The following home BP variability indicators were calculated biweekly: mean, maximum, minimum, difference between maximum and minimum, average real variability (ARV), SD, and coefficient of variation. Results In simple correlation, the ARV of systolic BP (SBP) (morning + evening and morning), maximum SBP (evening), and maximum diastolic BP (all time points) were most strongly correlated with UACR. In multivariate linear regression, the maximum, minimum, and ARV of SBP (morning) and both mean and maximum SBP (evening) were significantly associated with Box-Cox transformed UACR after adjustment for age, body mass index, and lifestyle. In particular, maximum SBP had the lowest P value among those BP indicators. Furthermore, maximum morning SBP tended to distinguish high-normal albuminuria (UACR ≥ 10 mg/g Cr) more clearly than mean morning SBP. The mean, maximum, and minimum values of home BP demonstrated the greatest reproducibility among all indicators. Conclusion Maximum home BP is associated with UACR and exhibits high reproducibility in perimenopausal women. These findings raise the hypothesis that maximum home SBP may be suitable to detect kidney damage.