Correlation between 24-h ambulatory systolic blood pressure and glomeruar filtration rate among the elder

Objective To investigate the correlation between the 24h ambulatory systolic blood pressure (SBP) and estimated glomeruar filtration rate (eGFR) in the elder.Methods A total of 2464 participants who were more than or equal to 60 years old were selected with random sampling in accordance with the inclusion criteria from the retired workers in Tangshan Kailuan Company. Finally, 1405 participants were enrolled, and the correlation between SBP and eGFR was analyzed. Multiple linear regression analysis was used to analyze the correlation between the 24h, daytime, nightime SBP and eGFR, respectively.Results The observation population was divided into three groups according to the tertiles of 24h, daytime, nightime SBP, respectively. With the increases of SBP, eGFR had increasing trend, but there was no significant difference.Partial correlation analysis showed negative association between 24h SBP and eGFR (r=-0.056, P=0.035), and no significant difference was found between daytime, nightime SBP and eGFR.Multiple linear regression analysis showed that after adjusting for confounding factors, the 24h, daytime, nightime SBP was not associated with eGFR significantly (B=-0.28, -0.14 and -0.34; P=0.619, 0.798 and 0.521). However, the clinic SBP was associated with eGFR negatively and linearly (P<0.05).Conclusions The 24h, daytime, nightime SBP was not significantly associated with eGFR, but there was negative association between clinic SBP and GFR. Closely monitoring blood pressure and keeping it at a low and steady level is essential to prevent and delay renal function decline.