Background
: 'Masked Hypertension' is a phenomenon of blood pressure that is normotensive by clinic measurement but proves to be hypertensive by 24 hour-AMBP and is associated with many cardiovascular complications and its clinical importance has become the center of public interest. However, in Korea no study concerning masked hypertension has ever been published so far. We investigated the frequency and the related factors of masked hypertension among Koreans.

Methods : Overall, 53 volunteers from Incheon and Seoul, Korea, who were 40 years old and abov were enrolled from August 2003 to August 2004. We checked their blood pressure and pulse rate every hour using an ambulatory blood pressure monitoring device [SpaceLabs 90207] for 24 hours. Masked hypertension was defined as office mean BP less than 140/90 mmHg and daytime mean BP over 135/85 mmHg.

Results : Among the total, 15 subjects met the criteria of masked hypertension (28.3%) Current smoking (P=0.021), higher clinic mean SBP (P=0.011) and DBP (P=0.027), and prehypertension (P=0.04) were identified as related factors. And when adjusted for sex by logistic regression, only current smoking was statistically significant (P=0.039) and prehypertension showed borderline significance (P=0.092) (CI=95%). Additionally, mean pulse pressures and mean standard deviation of individual mean SBP were higher in the masked hypertension group.

Conclusion : The frequency of masked hypertension was 28.3% the and related factors were current smoking and higher office BP, especially prehypertension that was introduced in JNC-7. The fact that the pulse pressure and the variability of individual SBP were higher in the masked hypertension group remains thought-provoking.

Background
: This study aimed at finding out how much the rate of the JNC-7 guideline was carried out, and assessed the degree of evidence based clinical practice patterns and the validity of the new guideline by comparatively analyzing primary care practice patterns in hypertensive patients.

Methods : A questionnaire regarding the management of hypertension was conducted by mail between May 15 and July 15, 2005, to 1,008 of the Korean Association of Family Medicine listed in the address book. There were 195 respondents with a response rate of 19.4%.

Results : Among the total respondents, 91.1% were aware of the new guideline and had received information mainly through training lectures and seminars. They said that the biggest difference between the new guideline from the previous one was the inclusion of prehypertension (62.3%), and 61.1% were using the new term prehypertension in their practice. The most frequency advice given to patients related to lifestyle modification were in the order of smoking cessation (44.8%), exercise (41.7%) and weight reduction (38.0%). Calcium channel blocker was the most commonly used (60.9%) as the first-line agent. When physicians failed to control blood pressure with the first medication in cases of stage 1 hypertension, 67.7% added other agents. In treating stage 2 hypertension, 59.9% started with a single agent and gradually added other agents.

Conclusion : Family physicians in primary care clinics had a good understanding of the JNC-7 guideline. However, the rate at which they applied it in treatment was low. To effectively apply the guideline in actual treatments, aggressive education of practitioners and improvement on medical system and treatment guidelines are needed.