Automated Office Blood Pressure Measurement Research Articles

Integration of Automated Office Blood Pressure Measurement Into a General Internal Medicine Residency Clinic.

Integration of Automated Office Blood Pressure Measurement Into a General Internal Medicine Residency Clinic.

Automated office blood pressure measurement with the assistance of an instructional video in patients with hypertension.

Automated office blood pressure (AOBP) measurement often requires assistance. Accompanied by an instructional video, AOBP measurement could be performed independently by patients. Seventy-five patients with hypertension were enrolled. AOBP was measured three times at 1-min intervals after 5 min of rest by an automated BP measurement device with the assistance of an animated instructional video. The video was designed originally to instruct patients on the way to measure BP appropriately. Perceived stress was evaluated using a questionnaire after the AOBP measurement. Office BP was measured three times using the same device. Home BP measurement was performed on 5 consecutive days. The mean age of the patients was 74.5 ± 10.6 years, and 96% were taking antihypertensive drugs. Mean AOBP, office BP and home BP measurements were 135.2 ± 17.2/81.3 ± 11.1, 139.3 ± 16.3/78.6 ± 10.9 and 129.2 ± 16.7/72.7 ± 8.9 mmHg, respectively. Regarding SBP, the mean AOBP was significantly lower than office BP ( P = 0.005) and higher than home BP ( P = 0.004). The differences in SBP and DBP between AOBP and home BP measurements were significantly related to patients' perceived stress when performing AOBP measurements ( r = 0.289; P = 0.013 and r = 0.328; P = 0.004). In a multivariate analysis, patients' perceived stress was a significant predictor of the difference between AOBP and home BP ( P = 0.013), even after adjusting for age, sex, BMI and mean of AOBP and home BP. AOBP values measured with the assistance of an instructional video were between conventional office and home BP measurements. Perceived stress during AOBP measurement was related to the difference in AOBP from home BP.

The Benefit of Unattended Automated Office Blood Pressure Measurement on the White-coat Effect: A Cross-sectional Study

Objective: To compare blood pressure (BP) and heart rate measured by attended and unattended automated office blood pressure measurement (AOBPM) versus home blood pressure measurement (HBPM) and the effect of unattended AOBPM on the classification of BP phenotypes. Materials and Methods: The cross-sectional study was conducted at the outpatient department in Siriraj Hospital, Thailand. All participants measured their office BP using attended and unattended techniques in random order and recorded home BP twice a day for consecutive 7 days. The agreement between office BP from both AOBPM methods and that from HBPM was analyzed using the Bland-Altman plot. The change in the proportion of each BP phenotype was also analyzed. Results: We included 114 participants. The mean age was 57.96 + 15.07 years. The average BP from attended AOBPM, unattended AOBPM, and HBPM were 150.52 + 16.12/81.77 + 11.04, 139.68 + 13.80/78.55 + 11.71, and 126.91 + 9.80/76.40 + 8.37 mmHg, respectively. The BP and heart rate measured by these techniques were significantly different (p-value of <0.001). Bland-Altman analysis showed the biases of attended and unattended SBP versus home SBP were 23.61 and 12.77 mmHg, respectively. Unattended AOBPM significantly decreased the numbers of patients classified as white-coat and sustained hypertension regardless of BP thresholds (p-value of <0.001 for both groups). Conclusion: Unattended AOBPM significantly minimizes the white-coat effect in real-life clinical practice and may help physicians avoid overdiagnosis of hypertension. Nevertheless, it does not replace HBPM.

The Prognostic Role of Automated Office Blood Pressure Measurement in Hypertensive Patients with Chronic Kidney Disease.

The aim of this study was to evaluate the prognostic value of automated office blood pressure (AOBP) measurement in patients with hypertension and chronic kidney disease (CKD) stage 3-5 not on dialysis. At baseline, 140 patients were recruited, and blood pressure (BP) measurements with 3 different methods, namely, office blood pressure (OBP), AOBP, and ambulatory blood pressure measurement (ABPM), were recorded. All patients were prospectively followed for a median period of 3.4 years. The primary outcome of this study was a composite outcome of cardiovascular (CV) events (both fatal and nonfatal) or a doubling of serum creatine or progression to end-stage kidney disease (ESKD), whichever occurred first. At baseline, the median age of patients was 65.2 years; 36.4% had diabetes; 21.4% had a history of CV disease; the mean of estimated glomerular filtration rate (eGFR) was 33 mL/min/1.73 m2; and the means of OBP, AOBP, and daytime ABPM were 151/84 mm Hg, 134/77 mm Hg, and 132/77 mm Hg, respectively. During the follow-up, 18 patients had a CV event, and 37 patients had a renal event. In the univariate cox regression analysis, systolic AOBP was found to be predictive of the primary outcome (HR per 1 mm Hg increase in BP, 1.019, 95% CI 1.003-1.035), and after adjustment for eGFR, smoking status, diabetes, and a history of CV disease and systolic and diastolic AOBP were also found to be predictive of the primary outcome (HR per 1 mm Hg increase in BP, 1.017, 95% CI 1.002-1.032 and 1.033, 95% CI 1.009-1.058, respectively). In patients with CKD, AOBP appears to be prognostic of CV risk or risk for kidney disease progression and could, therefore, be considered a reliable means for recording BP in the office setting.

PS-BPC06-9: THE EFFECT OF COMMON SURGICAL MASKS ON UNATTENDED BLOOD PRESSURE CHANGES IN DRUG TREATED HYPERTENSIVE PATIENTS

Objective: While there are several studies that have focused on the role of face masks in preventing airborne transmission of SARS-CoV-2, few data are available on their effects on physiological measures, and no study has examined their effects on blood pressure (BP). The purpose of our study was to investigate the effect of surgical masks on BP in drug-treated hypertensive patients who had a routine follow-up visit to a university hospital outpatient hypertension clinic. Design and method: The study included already treated hypertensive patients aged > 18 years, while the exclusion criteria were atrial fibrillation or any other arrhythmia affecting the BP measurement, an arm circumference > 42 cm, mental disorders, Parkinson disease, pregnancy, intolerance to the BP measurement method, or unwillingness to participate. A new surgical mask was provided to all participants to replace the face mask that was already in use. After the routine mask-on office BP measurement, patients were left alone and randomized to automated office BP measurement, with measurements taken after first wearing a mask for 10 min, then without wearing the mask for 10 min, and vice versa. Results: A total number of 265 patients were included in the study. Among the participants, 115 were women (43.4%), the mean age was 62 ± 12 years, and the mean office BP was 134 ± 15 / 81 ± 12 mmHg. There was no significant difference between mask-on unattended systolic BP (133 ± 15 mmHg) and mask-off unattended systolic BP (132 ± 15 mmHg) (P = 0.13) or between mask-on unattended diastolic BP (77 ± 13 mmHg) and mask-off unattended diastolic BP (76 ± 13 mmHg) (P = 0.32). Moreover, there was no difference in the heart rate (mask-on first, 69 ± 11 bpm; mask-off first, 69 ± 11 bpm, P = 0.7). Conclusions: Common surgical masks do not affect systolic/diastolic BP levels during unattended BP measurements in treated hypertensive patients.

Automated Office Blood Pressure Measurement Requires Technology and Implementation

Automated Office Blood Pressure Measurement Requires Technology and Implementation

AUTOMATED OFFICE BLOOD PRESSURE MEASUREMENT ASSITED BY INSTRUCTIONAL VIDEO IN HYPERTENSIVE PATIENTS

Objective: Automated office blood pressure (AOBP) is a better estimate of true blood pressure (BP) than clinic BP by physicians; however, measurement is complicated and requires some assistance by medical staffs especially for elderly patients. Video instruction explaining how to measure AOBP would be helpful to guide patients to measure AOBP by themselves. Design and method: We enrolled 75 hypertensive patients. AOBP was measured 3 times with one minute interval after 5 minutes of rest by automated BP device (A&D UM-212BLE) with assistance of instructional video. Instructional video was designed originally to describe the way to attach the cuff, press the button, and stay quiet and measure BP in appropriate position. Clinic BP by physician was measured 3 times using the same device. The sequence of AOBP and clinic BP was andomised. Perceived stress when measuring AOBP and clinic BP were evaluated by visual scale analogue. Home BP was taken 5 consecutive days using A&D UA-651BLE Plus. Results: Mean age was 74.5 ± 10.6 (57% men), and 96% of the patients were taking antihypertensive drugs. Mean AOBP, clinic BP, home BP were 135.2 ± 17.2/81.3 ± 11.1, 139.3 ± 16.3/78.6 ± 10.9, 129.2 ± 16.7/72.7 ± 8.9 mmHg respectively. Mean systolic AOBP was significantly lower than clinic BP (4.1 ± 12.2, p = 0.005), and significantly higher than home BP (6.1 ± 17.5, p = 0.004). Mean diastolic AOBP was significantly higher than clinic BP (-2.7 ± 6.0, p < 0.001), and significantly higher than home BP (8.6 ± 8.8, p < 0.001). Difference between AOBP and home BP was associated with magnitude of mental stress when measuring AOBP (r = 0.289, p = 0.013). In a multivariate analysis, mental stress when measuring AOBP was a predictor of difference between AOBP and home BP after adjusting for age, sex, body mass index, and average of home BP (p < 0.001). AOBP and clinic BP were higher among patients who felt stressed when measuring AOBP (r = 0.386, p < 0.001 for AOBP, r = 0.308, p = 0.008 for clinic BP). Conclusions: AOBP measured with assistance of instructional video were significantly lower than clinic BP and higher than home BP, and the differences were determined by magnitude of mental stress associated with AOBP and clinic BP measurement.

SURGICAL MASKS AND UNATTENDED BLOOD PRESSURE CHANGES IN TREATED HYPERTENSIVE PATIENTS

Objective: Although the effect of face masks on preventing airborne transmission of SARS-CoV-2 is well studied, few data are available on their effects on physiological measures and no study has evaluated their effect on blood pressure (BP). The purpose of our study was to investigate the effect of surgical masks on BP in drug-treated hypertensive patients who had a routine follow-up visit to a university hospital outpatient hypertension clinic. Design and method: The study included already treated hypertensive patients aged > 18 years, while the exclusion criteria were atrial fibrillation or any other arrhythmia affecting the BP measurement, an arm circumference > 42 cm, mental disorders, Parkinson’s disease, pregnancy, intolerance to the BP measurement method, or unwillingness to participate. Following the routine mask-on office BP measurement, patients were left alone and randomized to automated office BP measurement, with measurements taken after first wearing a mask for 10 min, then without wearing the mask for 10 min, and vice versa. Results: A total number of 265 patients were included in the study. Among the participants, 115 were women (43.4%), the mean age was 62 ± 12 years, and the mean office BP was 134 ± 15/81 ± 12 mmHg. There was no significant difference between mask-on unattended systolic BP (133 ± 15 mmHg) and mask-off unattended systolic BP (132 ± 15 mmHg) (P = 0.13) or between mask-on unattended diastolic BP (77 ± 13 mmHg) and mask-off unattended diastolic BP (76 ± 13 mmHg) (P = 0.32). Moreover, there was no difference in the heart rate (mask-on, 69 ± 11 bpm; mask-off, 69 ± 11 bpm, P = 0.7). Conclusions: The results of our study indicate that common surgical masks do not affect systolic/diastolic BP levels during unattended BP measurements.

Common surgical masks and unattended blood pressure changes in treated hypertensive patients.

Although the effect of face masks on preventing airborne transmission of SARS-CoV-2 is well studied, no study has evaluated their effect on blood pressure (BP). Therefore, we investigated the effect of surgical masks on BP in 265 treated hypertensive patients. Following the routine mask-on office BP measurement, patients were left alone and randomized to automated office BP measurement, with measurements taken after first wearing a mask for 10 min, then without wearing the mask for 10 min, and vice versa. Among the participants, 115 were women (43.4%), the mean age was 62 ± 12 years, and the mean office BP was 134 ± 15/81 ± 12 mmHg. There was no significant difference between mask-on unattended systolic BP (133 ± 15 mmHg) and mask-off unattended systolic BP (132 ± 15 mmHg) (P = 0.13) or between mask-on unattended diastolic BP (77 ± 13 mmHg) and mask-off unattended diastolic BP (76 ± 13 mmHg) (P = 0.32). Surgical masks had no effect on BP in treated hypertensive patients.

Comparison of automated office blood pressure measurement with 24-hour ambulatory blood pressure measurement

Purpose Although 24-hour ambulatory blood pressure measurement (24-h ABPM) is the most important method to establish true hypertension, in clinical practice often repeated automated office blood pressure (AOBP) measurements are used because of convenience and lower costs. We aimed to assess the agreement rate between a 30 and 60 min AOBP and 24-h ABPM. Materials and methods Patients with known hypertension (cohort 1) and patients visiting the neurology outpatient clinic after minor stroke or transient ischaemic attack (cohort 2) were selected. We performed AOBP for 30–60 min at 5-min intervals followed by 24-h ABPM and calculated average values of both measurements. Agreement between the two methods was studied with McNemar and Bland–Altman plots with a clinically relevant limit of agreement of ≤10 mm Hg difference in systolic BP. Results Our final cohort consisted of 135 patients from cohort 1 and 72 patients from cohort 2. We found relatively low agreement based on the clinical relevant cut-off value; 64.7% of the measurements were within the limits of agreement for 24-h systolic and 50.2% for 24-h diastolic. This was 61.4% for daytime systolic and 56.6% for daytime diastolic. In 73.5% of the patients, both methods led to the same diagnosis of either being hypertensive or non-hypertensive. This resulted in a significant difference between the methods to determine the diagnosis of hypertension (p < 0.0001). Conclusion We conclude that 30–60 min AOBP measurements cannot replace a 24-h ABPM and propose to perform 24-h ABPM at least on a yearly basis to confirm AOBP measurements.

Improving Efficiency of Automated Office Blood Pressure Measurements

Automated office blood pressure (AOBP) measurement reduces human error and improves precision. Guidelines recommend that patients rest for 5 minutes

Impact of 30- Versus 60-Second Time Intervals Between Automated Office Blood Pressure Measurements on Measured Blood Pressure.

[Figure: see text].

Abstract P124: Repeat Manual Office Blood Pressure By A Physician Is Lower Than Automated Office Blood Pressure

Introduction: An accurate measurement of blood pressure (BP) is critical to diagnosing and treating hypertension (HTN). Manual office BP (MOBP) often results in higher readings than automated office BP (AOBP). In previous studies, a repeat MOBP by a physician resulted in a lower BP than the initial MOBP by nursing staff. We evaluated our hypothesis that a repeat MOBP by a physician is statistically equivalent to AOBP. Methods: In an ambulatory outpatient setting, patients were roomed and at least a 5-minute interval lapsed before an AOBP was performed using a Welch Allyn Connex Vital Signs Monitor. The physician was blinded to the AOBP. The physician then entered the room and obtained a MOBP with a manual aneroid sphygmomanometer. The difference between the AOBP and the MOBP was calculated. A Wilcoxon signed rank sum test was used to determine if a significant difference between AOBP and MOBP exists. Results: A total of 186 patients (112 females, 74 male) had BP measured with a mean age of 66 years. AOBP resulted in a median systolic BP (SBP) 136 mmHg (IQR 121-150 mmHg) and median diastolic BP (DBP) of 78 mmHg (IQR 72-85 mmHg). MOBP SBP had a median of 132 mmHg (IQR 120-142 mmHg) and DBP had a median of 76 mmHg (IQR 70-81 mmHg). SBP and DBP were significantly lower in the MOBP group with a mean difference between AOBP and MOBP of 4.0 and 2.7 mmHg respectively (p-value of &lt;0.0001). Conclusions: Repeat MOBP performed by the physician resulted in a significantly lower BP compared to AOBP. The lower BP may be due to an overall longer interval between the AOBP measurement and MOBP measurement. MOBP may be a viable option for accurate diagnosis and treatment of HTN clinics without access to a AOBP machine.

Comparison of nurse attended and unattended automated office blood pressure with conventional measurement techniques in clinical practice.

Accuracy in blood pressure measurement is critical for proper hypertension diagnosis and treatment in clinical practice. Automated office blood pressure (AOBP) can simplify the measurement process, reducing human error and minimizing the white-coat effect in the unattended mode. The aim of this study was to compare AOBP, both unattended and nurse attended, with conventional office and out-of-office blood pressure measurement techniques. Four different methods of blood pressure measurement were performed in a cohort of hypertensive patients: conventional office blood pressure (OBP), unattended automated office blood pressure (uAOBP), nurse attended automated office blood pressure (nAOBP), and home blood pressure monitoring (HBPM). uAOBP and nAOBP were conducted with the same rigorous standardized procedure. We enrolled 118 consecutive patients. nAOBP values were slightly higher than uAOBP ones (respectively 132.8/73.3 ± 19.4/12.9 and 129.2/71.1 ± 19.0/12.3 mmHg), even if the difference was influenced by order of execution of AOBP measurement. nAOBP was significantly lower than HBPM and OBP (mean values 135.2/80.9 ± 16.6/8.1 and 140.9/84.6 ± 18.7/10.8 mmHg, respectively). AOBP, either attended or unattended, provides lower values than conventional OBP. uAOBP and nAOBP values showed small differences, even if they are not completely interchangeable. This evidence reflects a lower white-coat effect, even in nurse attended technique, but is also due to a lower measurement error through the application of a rigorous standardized protocol.

Randomized Controlled Trial Comparing Automated Office Blood Pressure Readings After Zero or Five Minutes of Rest.

[Figure: see text].

Correction to: Diagnostic Accuracy of Unattended Automated Office Blood Pressure Measurement in Screening for Hypertension in Kenya.

Correction to: Diagnostic Accuracy of Unattended Automated Office Blood Pressure Measurement in Screening for Hypertension in Kenya.

Sustained high blood pressure and 24-h ambulatory blood pressure monitoring in Tanzanian adolescents

Estimates for prevalence of high blood pressure (BP) among adolescents in Africa vary widely and few studies, if any, have documented the results of the recommended stepwise BP screening. In this cross-sectional study in Tanzania, we aimed to estimate prevalence of sustained high BP in 3 public secondary schools using the American Academy of Pediatrics BP screening strategy. On Day 1, one screening automated office BP (AOBP) measurement (Step 1) was followed by two more AOBP measurements (Step 2). Repeat AOBP measurements were obtained after about one month on adolescents with high AOBP measurements on Day 1 (Step 3). Participants with sustained high BP underwent 24-h ambulatory BP monitoring (step 4). Of all 500 enrolled participants, the prevalence of high blood pressure at each step in the process was 36.6% (183), 25.6% (128), 10.2% (51), and 2.6%(13) respectively for Steps 1–4. All except 6 students completed all 4 steps of the BP screening algorithm as indicated. We conclude that diagnosis of hypertension in African adolescents should use multiple AOBP measurements over multiple days followed by 24-h ABPM. Screening for high BP in school settings appears to be feasible and could provide a platform for cardiovascular disease education and health promotion.

ACCURACY OF SHORTER PROTOCOLS FOR AUTOMATED OFFICE BLOOD PRESSURE MEASUREMENTS

Abstract Objective: Blood pressure measurement (BPM) is one of the most often performed procedures in clinical practice but especially office BPM is prone to errors. Automated office BPM (AOBPM) is highly standardised and compares well to ambulatory BPM but is time and space consuming since the patient is placed alone during the procedure. With this analysis we compared the accuracy of different calculation methods to evaluate if an abbreviation of the AOBP protocol is possible. Design and method: In our retrospective single centre study, we used all AOBPM (AOBPM protocol of the SPRINT study), collected over 14 months. Three sequential BPM (after 5 minutes of rest, spaced 2 minutes) were automatically recorded with the patient alone in a quiet room resulting in three systolic (S1S2S3) and diastolic (D1D2D3) values. We compared the result of the first BPM (S1/D1) and the mean of the first two BPM (S1S2/D1D2) with the mean of all three BPM (S1S2S3/D1D2D3) which was regarded as goldstandard for AOBPM. Results: We analysed 413 AOBP sets from 210 patients with a median age of 52 years (IQR 38–66). Median mmHg (IQR) for S1, S1S2 and S1S2S3 were 128.0 (117.0–142.0), 127.5 (117.0–140.0), 127.7 (116.8–139.2) and for D1, D1D2 and D1D2D3 80.0 (75.0–86.5), 80.0 (75.5–86.5), 80.3 (75.7–86.5), respectively. A Wilcoxon signed rank test determined that there was a statistically significant median increase of systolic blood pressure (BP) applying S1 compared to S1S2S3 (0.3mmHg, z = 2.315, p = 0.021) but not for S1S2 vs S1S2S3. For diastolic BP there was a no statistically significant difference for D1 vs. D1D2D3 but for D1D2 vs. D1D2D3 (0.2mmHg, z = 2.05, p = 0.040). Regarding agreement absolute difference was within 2 mmHg in 85.5% of the AOBPM comparing S1S2 vs. S1S1S3 and 93.2% for D1D2 vs D1D2D3, respectively (for all comparisons see table). Bland-Altman plots for all comparisons are shown in the figure. Conclusions: Based on our results differences between S1S2 vs S1S2S3 and D1D2 vs D1D2D3 are minimal and within acceptable limits of agreement. Therefore the automated procedure may be shorted to 2 measurements.

INFLUENCE OF RESTING HEART RATE ON BLOOD PRESSURE LOWERING EFFECT

Objective: Elevated resting heart rate (RHR) identifies hypertensive subjects at higher cardiovascular risk. The study was aimed to compare benefit of intensive blood pressure (BP) lowering in subjects with higher and lower RHR. Design and method: The analysis was performed using Systolic Blood Pressure Intervention Trial (SPRINT) data shared by National Heart, Lung and Blood Institute. SPRINT trial assessed intensive lowering of systolic BP to a target &lt; 120 mm Hg in comparison to standard goal (&lt; 140 mm Hg). Baseline RHR was estimated as a pulse rate obtained during automated office BP measurements at first study visit. RHR higher than 80 b.p.m. was defined as increased according to current European Society of Cardiology guidelines. Composite outcome event (CE) included myocardial infarction and other acute coronary syndrome, stroke, heart failure decompensation and cardiovascular death. Cox proportional model was used to assess impact of BP lowering in subjects with RHR higher and lower than 80 bpm. P-value for interaction between study BP intervention and baseline RHR. Results: Data of 9361 SPRINT participants, aged 67.9 ± 9.4 years, were analyzed. 3332 (35.6%) were female an 1877 (20.1%) were diagnosed with prior cardiovascular disease. Mean baseline RHR was 66.3 ± 11.6 b.p.m. Baseline HR in both treatment arms was similar (standard arm 66.3 ± 11.7 b.p.m. vs intensive arm 66.2 ± 11.5 b.p.m., p = 0.762) 1198 (12.8%) participants had baseline RHR higher than 80 b.p.m. and experienced 78 (6.8%) CE events. There were 484 (5.9%) events among subjects with RHR lower than 80 b.p.m. Intensive lowering of systolic BP was beneficial both in subjects with elevated RHR (hazard ratio 0.79 with 95% confidence interval 0.51–1.24, p = 0.311) and non-elevated RHR (hazard ratio 0.75 with 95% CI 0.62–0.89, p = 0.002). The intervention between study BP intervention and baseline RHR was not significant (p for interaction 0.819). Conclusions: Elevated RHR does not influence effect of BP reduction on cardiovascular events risk.

Automated office blood pressure measurement by elderly patients in the waiting room.

Unattended automated office blood pressure (AOBP) may be a better estimate of true blood pressure (BP) than conventional office BP by physicians or nurses. However, measurement of AOBP is cumbersome in general clinical practice. We compared unattended AOBP by the patients themselves using the rigid cuff in the waiting room with attended AOBP and home BP (HBP) (N = 72). Unattended AOBP by patients was measured in the waiting room using a rigid cuff with the fully automated device (Omron, HEM-907, triple BP readings taken at 1-min intervals after 5 min of rest). Attended AOBP was measured using a soft cuff by a physician in an examination room without specific resting time. HBP was measured for 5 consecutive days. The mean age was 76.5 ± 8.6 years. The mean systolic unattended AOBP by patients, attended AOBP and HBP were 139.3 ± 16.6, 144.8 ± 17.1 and 139.1 ± 14.4 mmHg, respectively. Unattended AOBP by patients was significantly related to attended AOBP (r = 0.798; P < 0.01) and to HBP (r = 0.404; P < 0.001). It was significantly lower than attended AOBP (difference 5.5 ± 10.7 mmHg; P < 0.001) and comparable with HBP (difference 0.26 ± 17.0 mmHg; P = 0.90) in Bland-Altman plots. However, 22% of patients had a difference of over 20 mmHg between unattended AOBP by patients and HBP. Multivariate regression demonstrated older age (B = -0.73; P = 0.002) to be related to the difference between unattended AOBP by patients and HBP. The mean unattended AOBP by patients was lower than attended AOBP and comparable with HBP, but older age affected the difference between unattended AOBP by patients and HBP.