Incidence and Cardiovascular Risk Factors of White Coat Hypertension in Subjects with High Blood Pressure at Screening Examination

Abstract

In order to assess the incidence and cardiovascular risk status in white coat hypertension (WCH), we conducted a cross sectional study among subjects aged 30 to 65 who received screening examination. In 42 subject with normal casual blood pressure (CBP) (Control group: age 41±9), and 97 subjects with CBP≥140/90 mmHg (HBP group: age 46+11), 24-hour ambulatory blood pressure monitoring (ABPM), metabolic risk factors, fibrinogen, plasminogen activator inhibitor-I (PAT-I) and brain natriuretic peptide (BNP) were measured. Left ventricular mass index (LVMI) by M-mode UCG was measured in HBP group. We defined mean+l standard deviation of average 24-hour recordings from ABPM (24-ABPM) in Control group (128/80 mmHg) as an upper normal value. In 42 subjects of HBP group 24-ABPM was within normal range (WCH group) and remaining subjects were classified Hypertension group (n=55) . Age was not different among Control. CBP of WCH (140±12/89±6.9 mmHg) and Hypertension groups (141±10/92±7.2 mmHg) was higher than Control group (111±14/70±8.4 mmHg) . 24-ABPM in Control group (118±9.1 mmHg) and in WCH group (120, ± 4.6/72±3 .8 mmHg) and they were lower than that of Hypertension group (135±8.9/82 ± 6.0 mmHg) . LVMI of WCH group was tended to be smaller than that of Hypertension group. As compared with Control group, body mass index, total cholesterol, LDL-cholesterol, uric acid, fasting glucose and HbA_1c were higher in Hypertension group. HDL-cholesterol was lower and uric acid as well as HbA_1c was higher in WCH group. Fibrinogen, PAT-I and BNP were not different among groups.
These data suggest that WCH is common among health screening examination and ABP should be considered if WCH is suspected. Since WCH is associated with metabolic cardiovascular risk factors, proper life style modification should also be considered.