PS-P10-2: NON-LINEAR RELATIONSHIP BETWEEN CKD PROGRESSION AND SYSTOLIC AND DIASTOLIC BLOOD PRESSURE; IKI EPIDEMIOLOGICAL STUDY OF ATHEROSCLEROSIS AND CKD (ISSA-CKD)

Abstract

Objectives: The aim of the study is to assess the non-linear relationship between systolic and diastolic blood pressure and chronic kidney disease (CKD) progression. Design and Method: This is a cohort study using annual health check-up data from 2008 to 2018 in Iki City, Nagasaki, Japan. After excluding those who had health check-ups only once or those with the missing value for serum creatinine or urinalysis, a total of 5919 participants were included in the present analysis. The outcome of the present analysis was CKD progression, which was defined as worsening either the glomerular filtration rate stage or albumin creatinine ratio stage according to KDIGO classification at a visit and at the end of follow-up. Non-linear effects of SBP and DBP on the progression of CKD were evaluated by Cox proportional analysis with a restricted cubic spline controlling for confounding factors. Results: During a mean follow-up of 4.9 years, 1167(19.7%) CKD progression was observed. As each SBP and DBP were classified into quartiles, there was a linear relationship between SBP and CKD progression (p < 0.001 for trend), on the other hand, there was no linear relationship between DBP and CKD progression (p = 0.534 for trend). For restricted cubic spline, we found a sigmoid curve-like relationship between SBP and CKD progression, in which CKD progression increased in accord with BP increase. For DBP, we found a U-like shape relationship between DBP and CKD progression, in which there was the lowest risk at nearly 70–80 mmHg, and then the risk for CKD progression increased to both lower and higher DBP. Conclusions: The findings of the present analysis showed a near-linear trend that higher SBP had a significant relationship with an increase in CKD progression. On the other hand, the relationship between DBP and CKD progression was not linear, and both lower and higher DBP could be related to CKD progression.