Analyses of morning blood pressure surge and clinical parameters in patients with idiopathic membranous nephropathy

Objective To observe the effect of morning blood pressure surge on clinical parameters in patients with idiopathic membranous nephropathy（IMN）. Methods For this cross-sectional study，168 patients with IMN were recruited and assigned into two groups according to the status of 24 h arterial blood pressure. The t-test or rank sum test was utilized for comparing the inter-group differences in clinical parameters. Logistic regression was employed for examining the influencing factors of morning blood pressure surge in IMN patients. Results Significant inter-group differences existed in age ［（51.04±9.67） years vs（46.99±13.14） years］，blood urea nitrogen（BUN） ［（5.90±1.59） mmol/L vs（4.64±1.19） mmol/L］，serum creatinine［（81.81±34.66） μmol/L vs（69.58±24.97） μmol/L］，estimated glomerular filtration rate（eGFR） ［（92.66±19.50）mL·min^-1·（1.73m²）^-1 vs（103.39±23.82） mL·min^-1·（1.73m²）^-1］，uric acid［（393.63±97.67）μmol/L vs（347.37±94.03）μmol/L］，albumin ［（25.26±7.44）g/L vs（28.41±5.50）g/L］，24 h urinary protein quantification［（6.37±4.43）g vs （4.46±2.26）g］and degree of renal interstitial injury（P<0.05）. No significant inter-group differences existed in body mass index［（27.32±3.54） kg/m² vs（26.49±4.11） kg/m²］，triglyceride［（3.18±2.74） mmol/L vs（2.96±1.78）mmol/L］，cholesterol［（6.75±1.80）mmol/L vs（6.54±1.69）mmol/L］， high-density lipoprotein［（1.24±0.41）mmol/L vs（1.30±0.41）mmol/L］or low-density lipoprotein ［（4.54±1.48）mmol/L vs（4.46±1.46）mmol/L］ （P>0.05）. Univariate Logistic regression analysis indicated that gender，BUN，serum creatinine，eGFR，uric acid（UA），albumin and renal interstitial injury were the relevant influencing factors of morning surge of blood pressure（P<0.05）. Multivariate Logistic regression analysis revealed that UA，albumin and renal interstitial injury were risk factors for morning surge of blood pressure（P<0.05）. Conclusion In patients with morning surge of blood pressure， degree of renal interstitial injury is significantly higher than that in those without. Thus interventional therapy of blood pressure is vital for IMN patients.