Blood pressure rhythm and its association with clinicopathological indices in patients with IgA nephropathy / 中华肾脏病杂志

ABSTRACT

Objective To investigate the blood pressure circadian rhythm in patients with IgA nephropathy by ambulatory blood pressure monitoring and explore its role in the disease progression. Methods A cross sectional study was carried out.Blood pressure rhythm was studied by ambulatory 24-hour monitoring with a portable oscillometric recorder in selected patients with primary IgA nephropathy.The term dipper was described as blood pressure during night dropped at least 10％ below daytime blood pressure.The term non-dipper referred to those in whom the nocturnal decline in blood pressure was less than 10％.Clinicopathological indices between dipper and non-dipper groups were compared. Results Ninety-three patients completed ambulatory blood pressure monitoring among whom 68 (73％) patients were non-dipper.The frequency of non-dipper was 70％,70％ and 81％ in the patients at chronic kidney disease stage 1,2 and 3 or more.The frequency did not differ among these three group patients (P=-0.587).77％ of patients with hypertension and 69％ of patients with normotension were non-dipper (P=0.373).The disappearance of blood pressure circadian rhythm in IgA nephropathy was not influenced by age,gender,blood pressure,proteinuria,renal function and renal pathology lesions.Among the patients who were followed up regularly for more than 12 months (n=54),patients in the dipper group had a trend of slower eGFR decline rate than those in non-dipper group albeit the difference was not significant (P=0.329).Subgroup analysis revealed that in patients with hypertension and non-dipper (n=29),the eGFR decline rate was much faster than that in dipper group[(-6.79±11.58 )vs (-0.34±1.74) ml ·min-1 ·(1.73 m2)-1·year-1,P=0.019]. Conclusions Most patients with IgA nephropathy present disappearance of blood pressure circadian rhythm,even among those at an early stage or without hypertension.The loss of blood pressure rhythm may be associated with a rapid renal function decline rate in those with hypertension.