Abnormal circadian blood pressure pattern 1-year after kidney transplantation is associated with subsequent lower glomerular filtration rate in recipients without rejection

Abstract

Abnormal circadian blood pressure (BP) pattern is common after kidney transplantation but its relationship to long term allograft function is unclear. Of 119 kidney recipients who had ambulatory BP monitoring 1 year from transplantation, 36 patients without history of rejection were selected. Twenty-nine recipients were followed for 4 years and seven for 3 years. Iothalamate glomerular filtration rate (GFR) was obtained at 3 weeks then annually. Dippers (n = 10) had day-night systolic BP (SBP) drop (ΔSBP) of ≥10%, nondippers (n = 15) had ΔSBP 0%-9%, whereas reverse dippers (n = 11) had nocturnal rise in SBP. Compared with dippers, reverse and nondippers had a higher Banff cv score at 1 year (P = .03), lower GFR at last follow-up (73.7 ± 18.1, 55.7 ± 16.3, and 56.6 ± 21 mL/min/1.73 m(2) for dippers, non-, and reverse dippers, respectively, P = .05) and higher kidney function loss (8.0 ± 20, -9 ± 17, and 1 ± 14 mL/min/1.73 m(2) for dippers, non-, and reverse dippers, respectively, P = .02). GFR at 4 years and at last follow-up independently correlated with ΔSBP at 1 year (r = 0.46, P = .01; r = 0.34, P = .03). The current study indicates that abnormal circadian BP pattern at 1 year identifies a group of kidney recipients at risk for increased kidney function loss and lower GFR 3-4 years from transplantation.