21st European Meeting on Hypertension and Cardiovascular Prevention

Preliminary findings from an international hypertension registry have shown that uncontrolled hypertension is more commonly detected by clinic measurements than by 24-hour ambulatory blood pressure monitoring (ABPM). Gianfranco Parati, University of Milan-Bicocca, Milan, Italy, presented the results of the first interim analysis of the observational study.

The International Ambulatory Blood Pressure Registry: Telemonitoring of Hypertension and Cardiovascular Risk Project (ARTEMIS) is an ongoing study designed to assess the prevalence of different hypertension phenotypes, as defined by patterns of clinic blood pressure readings and ABPM values, in patients managed in blood pressure clinics worldwide. The ‘isolated clinic hypertension’ phenotype describes patients with elevated clinic blood pressure readings (≥140/90 mmHg) but normal ABPM measurements. Conversely, the ‘masked hypertension’ phenotype describes patients with normal clinic readings but elevated average 24-hour ABPM readings (≥130/80 mmHg). Sustained uncontrolled hypertension describes patients with elevated blood pressure detected both in the clinic and via 24-hour monitoring.

This preliminary report from ARTEMIS reflected data from 9189 patients across 21 countries in Europe (n = 7,522), South America (n = 266), Asia (n = 1,190), and Oceania (n=211). The mean age of patients was 56 years (range, 17 to 92 years). The mean body mass index was 28 kg/m2 (range, 16 to 60 kg/m2), and the mean waist circumference was 99 cm (range, 34 to 193 cm). Patients had several risk factors, including established cardiovascular disease (13%), diabetes (16%), dyslipidemia (32%), and smoking (19%). Less than half of patients (48%) were undergoing treatment for hypertension.

Clinic blood pressure readings correlated with average 24-hour ABPM values. The association was significant both for systolic blood pressure (SBP; r = 0.511; p <0.0001) and diastolic blood pressure (DBP; r = 0.566; p <0.0001).The mean SBP was 146 mmHg according to clinic measurements, and 130 mmHg according to average 24-hour ABPM readings. Mean DBP was 88 mmHg in the clinic and 78 mmHg averaged over 24 hours of ambulatory monitoring.

Uncontrolled hypertension was more likely to be detected by clinic blood pressure measurements than ABPM values (69% vs 58%; p <0.0001). In the overall study population, 23% of patients had isolated clinic hypertension, 11% had masked hypertension, and 47% had sustained uncontrolled hypertension.

Hypertension phenotypes varied in prevalence by geographic region. Sustained uncontrolled hypertension was more common in Europe and South America compared with the Asia-Oceania region (51% vs 22%; p <0.0001). Conversely, masked hypertension was less common among patients in Europe and South America than among those in Asia and Oceania (9% vs 24%; p <0.0001).

Hypertension phenotype also varied according to whether patients were receiving antihypertensive treatment. Isolated clinic hypertension was more common among treated patients than among untreated participants (26% vs 20%; p <0.0001). By comparison, untreated patients were more likely than treated patients to have masked hypertension (12% vs 10%; p <0.001) or sustained hypertension (52% vs 44%; p <0.0001).

ARTEMIS continues to enroll patients from hypertension clinics across the world. Future reports from ARTEMIS registry will provide further insight on the role of ABPM in hypertension monitoring and treatment.