Comparison of office, home and ambulatory blood pressure measurements in hypertensive and suspected hypertensive SWICOS participants.

PURPOSE

Hypertension should be confirmed with the use of home BP measurement (HBPM) or 24h ambulatory BP measurement (ABPM). The aim of our study was to compare measurements obtained by OBPM, HBPM and ABPM in individuals with elevated OBPM participating in the population-based Swiss Longitudinal Cohort Study (SWICOS).

MATERIAL AND METHODS

Participants with OBPM ≥140/90 mmHg assessed their BP using HBPM and ABPM. The cut-off for hypertension was ≥135/85 mmHg for HBPM, ≥130/80 mmHg for ABPM. White-coat hypertension (WCH) was defined as normal HPBM and ABPM in participants not taking antihypertensive drugs. Uncontrolled hypertension was defined as hypertension in HBPM or ABPM despite antihypertensive treatment.

RESULTS

Of 72 hypertensive subjects with office BP ≥140/90 mmHg and valid measurements of HBPM and ABPM, 39 were males (aged 62.8 ± 11.8y), 33 were females (aged 57.4 ± 14.2y). Hypertension was confirmed with HBPM and ABPM in 17 participants (24%), with ABPM only in 24 further participants (33%), and with HBPM only in 2 further participants (3%). Participants who had hypertension according to ABPM but not HBPM were younger (59 ± 11 y versus 67 ± 16 y;  < 0.001) and more frequently still working (83% versus 23%;  < 0.001). The prevalence of WCH was 28%. Among the 32 subjects taking antihypertensive drugs, uncontrolled hypertension was found in 49%.

CONCLUSION

This population-based study found a high prevalence of WCH and potential uncontrolled hypertension among individuals with elevated OBPM. This study, therefore, supports the ESH recommendations of complementing OBPM by ABPM or HBPM. The use of HBPM instead of ABPM for the confirmation of hypertension in individuals with elevated OBPM might lead to underdiagnosis and uncontrolled hypertension, in particular in the younger working population. In these individuals, this study suggests using ABPM instead of HBPM.