Differences between office and 24-hour blood pressure control in hypertensive patients with CKD: A 5,693-patient cross-sectional analysis from Spain

Am J Kidney Dis. 2013 Aug;62(2):285-94. doi: 10.1053/j.ajkd.2013.03.025. Epub 2013 May 18.

Abstract

Background: Previous studies have examined control rates of office blood pressure (BP) in chronic kidney disease (CKD). However, recent evidence suggests major discrepancies between office and 24-hour BP values in hypertensive populations. This study examined concordance/discordance between office- and ambulatory-based BP control in a large cohort of patients with CKD.

Study design: Cross-sectional.

Setting & participants: 5,693 hypertensive individuals with CKD stages 1-5 from the Spanish ABPM (ambulatory BP monitoring) Registry.

Predictors: Thresholds of 140/90 and 130/80 mm Hg for office BP and 24-hour ambulatory BP, respectively. Age, sex, body mass index, waist circumference, hypertension duration, kidney measures, diabetes, dyslipidemia, target-organ damage, and cardiovascular comorbid conditions.

Outcomes: Misclassification of BP control as "white-coat" hypertension (office BP ≥140/90 mm Hg, 24-hour BP <130/80 mm Hg) or masked hypertension (office BP <140/90 mm Hg, 24-hour BP ≥130/80 mm Hg).

Measurements: Standardized office-based BP and 24-hour ABPM.

Results: Mean age was 61.0 ± 13.9 (SD) years and 52.6% were men. The proportion with white-coat hypertension was 28.8% (36.8% of patients with office BP ≥140/90 mm Hg) and that of masked hypertension was 7.0% (but 32.1% of patients with office BP <140/90 mm Hg). Female sex, aging, obesity, and target-organ damage were associated with white-coat hypertension; aging and obesity were associated with masked hypertension. Only 21.7% and 8.1% of the CKD population had office BP <140/90 and <130/80 mm Hg, respectively. In contrast, 43.5% of individuals had average 24-hour BP <130/80 mm Hg.

Limitations: Cross-sectional design, longitudinal associations cannot be established.

Conclusions: Misclassification of BP control at the office was observed in 1 of 3 hypertensive patients with CKD. Ambulatory-based control rates were far better than office-based rates. Nevertheless, the burden of uncontrolled ambulatory BP and misclassification of BP control at the office constitutes a call for wider use of ABPM to evaluate the success of hypertension treatment in patients with CKD.

Keywords: Chronic kidney disease; ambulatory; control; hypertension; treatment.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Blood Pressure
  • Blood Pressure Monitoring, Ambulatory*
  • Cross-Sectional Studies
  • Female
  • Humans
  • Hypertension / complications*
  • Hypertension / diagnosis*
  • Hypertension / physiopathology
  • Hypertension / prevention & control
  • Male
  • Middle Aged
  • Office Visits
  • Renal Insufficiency, Chronic / complications*
  • Spain