OPTIMAL HOME BLOOD PRESSURE MONITORING SCHEDULE IN PATIENTS WITH ATRIAL FIBRILLATION

Objective: To investigate the optimal number of home BP (HBP) measurements in terms of agreement with reference ambulatory BP (ABP) monitoring in individuals with permanent atrial fibrillation (AF). Design and method: Adults with AF underwent 24 h ABP (measurements at 20 minutes intervals, Microlife WatchBP03) and HBP (duplicate morning/evening measurements for 7 days, Microlife WatchBP Home-N) measurements in random order. Different schedules of HBP were evaluated by analyzing the average BP value across an increasing number of measurement days, as well as their diagnostic agreement with awake ABP (hypertension was defined as BP >=135/85 mmHg for untreated patients, whereas uncontrolled BP as >=130/80 mmHg for treated patients). Results: Data from 26 participants were analyzed (mean age [SD] 75±7.3 years, 73% men, body mass index 30.2±5.3 kg/m2, 19% cardiovascular disease, 73% treated hypertension). Average systolic/diastolic HBP (7-days schedule; average number of measurements: 24.7±3.9) was 127.7±16.8/80.1±12.1 mmHg, and awake ABP 118.6±12.1/74.4±9.4 mmHg (p<0.01 for between methods comparisons). The average HBP was similar across increasing number of measurement days, whereas the first day was not higher versus the others (Figure 1A). By averaging an increasing number of HBP readings, there was a consistent trend towards stronger association with awake ABP (correlation coefficients r increased from 0.59 to 0.71 for systolic and from 0.62 to 0.71 for diastolic, all p<0.01) with plateau reached at first 3 days (Figure 1B). The diagnostic agreement between HBP and awake ABP was at 62% (kappa 0.23) for all different schedules. Conclusions: These preliminary findings support the recommendation for 7 days of HBP monitoring with a minimum of 3 days in patients with AF.