Authors: (including presenting author): :
Zhu Y(1), Chiang LK(1), Ko SH(1), Chen XRC(1)
Affiliation: :
(1) Department of Family Medicine & Primary Healthcare, Kowloon Central Cluster
Keyword 1: :
white-coat hypertension
Keyword 2: :
ambulatory blood pressure monitoring
Keyword 3: :
blood pressure variability
Keyword 4: :
primary care
Introduction: :
White-coat hypertension (WCHT) is a common condition encountered in primary care. WCHT has a higher long-term risk of progression to sustained hypertension (SHT) compared to normotensive individuals. Local data on the incidence of development of SHT among WCHT patients in primary care in Hong Kong is still lacking.
Objectives: :
To examine the incidence rate and risk factors of progression to SHT among WCHT patients in primary care in Hong Kong over 5 years.
Methodology: :
This was a retrospective cohort study. Adult Chinese patients diagnosed as WCHT by 24-hour ambulatory blood pressure monitoring (ABPM) from 1 January 2017 to 31 December 2018 from primary care clinics of Kowloon Central Cluster in the Hospital Authority of Hong Kong were recruited. The yearly cumulative incidence rates of progression to SHT among WCHT patients over a 5-year period were calculated. The associated risk factors were explored by multiple logistic regression analysis.
Result & Outcome: :
172 WCHT patients were included in this study. The yearly cumulative incidence rates of new SHT over 5-year follow-up were 4.7%, 11.6%, 20.3%, 29.7% and 37.8% respectively. Older age and higher baseline awake mean systolic ABP were found to be independent significant risk factors associated with the progression from WCHT to SHT, with odds ratios being 1.07 (95% CI 1.03-1.11) and 1.06 (95% CI 1.01-1.11) respectively. Higher average real variability (ARV), a measure of ABP variability, of 24-hour diastolic ABP at baseline is another independent risk factor with odds ratio of 1.19 (95% CI 1.03-1.37). A substantial proportion of WCHT patients progressed to SHT over a 5-year period. Family physicians should provide regular monitoring for WCHT patients, especially for older patients and subjects with higher baseline awake mean ABP. ARV is a potential novel variable of prediction of WCHT progression in the future.
