Predictive power of home blood pressure and clinic blood pressure in hypertensive patients with impaired glucose metabolism and diabetes.

OBJECTIVES

We evaluated the predictive power of home blood pressure and clinic blood pressure based on the long-term cardiovascular outcome in hypertensive patients with and without impaired glucose metabolism (IGM).

METHOD: The multicentre Hypertension Objective Treatment Based on Measurement by Electrical Devices Blood Pressure trial (HOMED-BP) involved 3080 patients (50.5% women; mean age 59.7 years) with a baseline, untreated home/clinic blood pressure as well as follow-up, on-treatment blood pressure. Of those, 979 had IGM and 475 of these patients had diabetes. We applied Cox regression pooling all participants in a cohort analysis in which IGM and normal glucose metabolism (NGM) were separated.

RESULTS

During median 5.45 years follow-up, cardiovascular events occurred in 48 patients with IGM and 53 patients with NGM. Baseline home SBP significantly predicted cardiovascular outcome among IGM group [hazard ratio 1.68, 95% CI 1.26-2.26, P = 0.0005]. On-treatment home blood pressure was a significant predictor for cardiovascular risk even after the further adjustment of baseline blood pressure level (P ≤ 0.027), whereas on-treatment clinic blood pressure was not in NGM group (P ≥ 0.37). The event rate in IGM was approximately two times higher than that in NGM (9.95 vs. 4.88 per 1000 patient-years), resulted to the low 5-year number needed to treat in IGM patients [83 vs. 121 for 1-SD (13.1 mmHg) home SBP reduction, and 62 vs. 104 for 1-SD (9.5 mmHg) home DBP reduction).

CONCLUSION

The present findings suggest that long-term cardiovascular risk in IGM patients should be assessed based on home blood pressure, not on clinic blood pressure.