Background:
We recently demonstrated how orthostatic hypotension might be used to identify out-of-office blood pressure phenotypes, including white coat effects and nocturnal non-dipping patterns. However, these findings have not been replicated in a population with chronic kidney disease (CKD).
Objective:
To examine the association between orthostatic hypotension (OH) or hypertension (OHTN) with ambulatory BP in adults with CKD.
Methods:
CRIC is a prospective multicenter observation cohort study of participants with CKD. Standing BP at 1 minute and ABPM were obtained on 1467 participants. OH was defined as a 20mmHg drop in systolic BP (SBP) or 10 mmHg drop in diastolic BP (DBP) when changing from seated to standing positions. OHTN was defined as a 20 mmHg or 10mmHg rise in SBP or DBP respectively when changing from seated to standing position. White coat effects, based on ABPM, was defined as the difference between seated clinic and ambulatory BP. Systolic and diastolic night to day ratio was also calculated.
Results:
Of the 1467 participants (age: 58 ± 10 yrs, 44% female, 39% black) 73 had OH and 165 had OHTN). OH was positively associated with systolic and diastolic white coat effect (β=5.9 [0.9, 10.9] and 4.2 [1.3, 7.1]). OHTN was negatively associated with diastolic white coat effect (-4.9 [-6.9, -3]). OH was positively associated with systolic and diastolic night-to-day ratio (0.03 [0.01, 0.05] and 0.03 [0.01, 0.06] respectively).
Conclusions:
Clinic-based assessments of OH and OHTN may be useful for identifying BP phenotypes often missed with seated office BP measurements in CKD patients.
Prevalence and clinical correlates of white coat effect in patients with chronic kidney disease and the role of automated blood pressure device in its assessment