Abstract: FR-PO546

Comparison of Blood Pressure (BP) Methods and Setting in Children with CKD

Session Information

Category: Hypertension

  • 1106 Hypertension: Clinical and Translational - Secondary Causes

Authors

  • Brady, Tammy M., Johns Hopkins University, Baltimore, Maryland, United States
  • Chung, Shang-En, Johns Hopkins University, Baltimore, Maryland, United States
  • Eakin, Michelle N., Johns Hopkins University, Baltimore, Maryland, United States
  • Goodman, Andrea C, Johns Hopkins University, Baltimore, Maryland, United States
  • Pruette, Cozumel S., Johns Hopkins University, Baltimore, Maryland, United States
  • Fivush, Barbara A., Johns Hopkins University, Baltimore, Maryland, United States
  • Tuchman, Shamir, Children's National Medical Center, Washington, District of Columbia, United States
  • Mendley, Susan R., University of Maryland, Baltimore, Maryland, United States
  • Riekert, Kristin, Johns Hopkins School of Medicine, Baltimore, Maryland, United States
Background

Children with CKD are at greater risk for hypertension and high BP is a risk factor for CKD progression. Multiple methods exist to measure BP in clinical practice.We aimed to determine how differing methods of BP measurement:1) correlate with each other and 2) correctly identify hypertensive status.

Methods

Cross-sectional analysis of 116 children in the CKD: Hypertension Adherence in Teens (CHAT) study at baseline. Enrolled children were 11-19 years of age, had CKD, and were prescribed ≥1 BP medication. Children had a clinic BP, 3 consecutive standardized home oscillometric BPs, and gold-standard 24-hour ambulatory BP (ABPM). BP index (BPi; measured BP/95th %ile BP; BP≥1 indicates hypertension) was calculated to standardize comparisons between BP measurements. Spearman correlation and Cohen’s Kappa coefficient (k) were used to compare measurement methods.

Results

Mean age 15.6 +/-2.6 yrs, 53% African American, and 55% male. CKD Stage: I 23%; II 38%; III 26%; IV 6.3%; V 7.3%. 32% of children were classified as hypertensive via day ABPM measurements compared with 20% via home BP (mean or 1st value) and 26% via clinic BP. The prevalence of normotension was 37% using ABPM measurements. Compared to this gold standard, average home BP classified 70% as normotensive (k 0.23), 1st home BP classified 62% as normotensive (k 0.18), and clinic BP classified 53% as normotensive (k 0.2). Clinic BP did not correlate well with other methods of BP measurement [Table].

Conclusion

BP measured in clinic correlates poorly with other standardized measurements of BP and resulted in underdiagnosis of hypertension when compared to BPs obtained by gold-standard ABPM. Home BP measurements, used frequently in place of ABPM, also underdiagnosed hypertension. This underscores the importance of ABPM as part of routine care of children with CKD.

Spearman Correlation of Different BP Measurements
SBPHome 1st SBP index
Home mean SBP index
Mean awake SBP index
Clinic SBP index0.160.120.24
Home 1st SBP index 0.95*0.52*
Home mean SBP index  0.53*
DBPHome 1st DBP indexHome mean DBP indexMean awake DBP index
Clinic DBP index0.33*0.32*0.26*
Home 1st DBP index 0.94*0.56*
Home mean DBP index  0.62*

*p<0.05

Funding

  • NIDDK Support