Long-Term Stroke Risk Due to Partial White-Coat or Masked Hypertension Based on Home and Ambulatory Blood Pressure Measurements: The Ohasama Study

Hypertension. 2016 Jan;67(1):48-55. doi: 10.1161/HYPERTENSIONAHA.115.06461. Epub 2015 Nov 2.


The prognostic significance of white-coat hypertension (WCHT) is controversial, and different findings on self-measured home measurements and 24-h ambulatory monitoring make identifying WCHT difficult. We examined whether individuals with partially or completely defined WCHT, as well as masked hypertension, as determined by different out-of-office blood pressure measurements, have a distinct long-term stroke risk. We followed 1464 participants (31.8% men; mean age, 60.6±10.8 years) in the general population of Ohasama, Japan, for a median of 17.1 years. A first stroke occurred in 212 subjects. Using sustained normal blood pressure (events/n=61/776) as a reference, adjusted hazard ratios for stroke (95% confidence intervals; events/n) were 1.38 (0.82-2.32; 19/137) for complete WCHT (isolated office hypertension), 2.16 (1.36-3.43; 29/117) for partial WCHT (either home or ambulatory normotension with office hypertension), 2.05 (1.24-3.41; 23/100) for complete masked hypertension (both home and ambulatory hypertension with office normotension), 2.08 (1.37-3.16; 38/180) for partial masked hypertension (either home or ambulatory hypertension with office normotension), and 2.46 (1.61-3.77; 42/154) for sustained hypertension. When partial WCHT and partial masked hypertension groups were further divided into participants only with home hypertension and those only with ambulatory hypertension, all subgroups had a significantly higher stroke risk (adjusted hazard ratio ≥1.84, P≤0.04). In conclusion, impacts of partial WCHT as well as partial masked hypertension for long-term stroke risk were comparable to those of complete masked hypertension or sustained hypertension. We need both home and 24-h ambulatory blood pressure measurements to evaluate stroke risk accurately.

Keywords: blood pressure; epidemiology; hypertension; population; stroke.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Blood Pressure / physiology*
  • Blood Pressure Monitoring, Ambulatory / methods*
  • Female
  • Follow-Up Studies
  • Forecasting*
  • Humans
  • Incidence
  • Japan / epidemiology
  • Male
  • Middle Aged
  • Retrospective Studies
  • Risk Assessment / methods*
  • Risk Factors
  • Stroke / epidemiology*
  • Stroke / etiology
  • Time Factors
  • White Coat Hypertension / complications*
  • White Coat Hypertension / physiopathology