A comprehensive risk score incorporating 24-hour ambulatory blood pressure.

Abstract

Although ambulatory blood pressure (BP) monitoring is required for the proper diagnosis and management of hypertension, conventional office BP has not yet been replaced by ambulatory BP in the currently available risk charts. For the current analysis, we selected 9,024 participants from the International Database on Ambulatory blood pressure in relation to Cardiovascular Outcomes (IDACO) aged ≥40 to <80 years with a baseline ambulatory BP recording including ≥6 daytime and ≥3 nighttime reading. Given the age range of the analyzed participants, we focused on systolic BP as a risk factor. Time-to-event analysis was conducted using the Cox model, and the 5-year risk was computed using the established formula used in the Heart “OMics” in AGEing (HOMAGE) study (J Am Heart Assoc 2017:e005231). Age at enrolment averaged 59.0 years, 48.2% women, and average 24 h systolic BP was 125.8 mmHg. The median number of ambulatory readings recorded over 24 h and the median follow-up of the cohort was 55 (ranging across cohorts from 37 to 80) and 13.9 years (from 4.0 to 23.3 years), respectively. All endpoints—composite cardiovascular endpoints, cardiovascular mortality, and total mortality—were positively associated with 24-h systolic BP, being on antihypertensive drug treatment at baseline, age, male sex, smoking, a history of cardiovascular disease, having diabetes, and non-drinking alcohol (P≤0.0032). Total mortality was inversely associated with body mass index and total cholesterol, whereas the composite cardiovascular endpoint and cardiovascular mortality were not. None of the endpoints was associated with Non-Asian versus Asian ethnicity (P≥0.31). Based on these findings, we constructed a risk score for each endpoint. The reference category was assigned to young (40–44 years old), women, no smoker, body mass index between 25–29 kg/m2, total serum cholesterol between 5.17–6.20 mmol/L, no diabetes, no history of cardiovascular disease, drinker, and 24-h ambulatory BP of <110 mmHg. The relative risk of cardiovascular events among the quintile of the scores in the participants was clearly separated, and estimated versus observed outcomes across the quintile groups demonstrated similar trends with showing good agreement. Although replication has not yet been fully achieved, the current risk calculator can be a valuable tool for healthcare providers as well as people for introducing ambulatory BP monitoring to the early detection and intervention for the general population and treatment naïve patients with high BP.