Blood Pressure Measurements In Studies Research Articles

Attended vs unattended systolic blood pressure measurement: A randomized comparison in patients with cardiovascular disease.

Recent clinical guidelines recommend lower blood pressure (BP) goals for most patients, and recent trends have favored use of automated unattended BP measurements in the office setting to minimize observer error and white-coat effects. Patients attending a routinely scheduled CVD clinic visit were prospectively randomized to BP measured using an attended, followed by an unattended method, or vice versa, after a controlled rest period. All study BP measurements were obtained in triplicate using the automated Omron HEM-907XL BP monitor, and averaged. The outcome was difference in SBP. Routinely measured clinic BP from the same visit was extracted from the medical record, and compared with attended and unattended BP. A total of 102 patients were randomized, and mean age was 63years, 52% female and 75% Caucasian. Attended and unattended SBP was 125.4±20.4 and 122.6±21.0mm Hg, mean±SD, respectively. Routine clinic SBP was 130.6±23.6mm Hg. Attended SBP was 2.7mm Hg higher than the unattended measurement (95% CI 1.3-4.1; P=.0002). Routine clinic SBP was 5.2mm Hg higher than attended SBP (95% CI 2.4-8.0; P=.0003) and 8.0mm Hg higher than unattended SBP (95% CI 5.4-10.5; P<.0001). Attended measurement of BP is significantly higher than unattended measurement and the difference is physiologically meaningful, even in a CVD cohort with generally well-controlled hypertension. Furthermore, routine clinic SBP substantially overestimates both attended and unattended automated SBP, with important implications for treatment decisions like dose and/or drug escalation.

Low Quality of Reports on Blood Pressure in Patients Adrenalectomized for Unilateral Primary Aldosteronism.

Adrenalectomy is the preferred treatment for unilateral primary aldosteronism but the results of long-term control of blood pressure (BP) are far from optimal. One possible explanation relates to the quality of the assessment of treatment effects on BP. To examine the quality of reporting BP measurements in studies assessing the outcome of adrenalectomy on BP. We conducted a systematic review searching 3 databases (PubMed, EMBASE, Web of Science) for articles published from January 1, 1990, onwards. Sixty-six studies, each reporting on more than 50 adrenalectomized patients, were eligible for full analysis. In 37 of the analyzed 66 studies (56.1%) BP values both before and after adrenalectomy were reported. In 19.7% (13/66) of the studies the method of BP measurement was described. The number of visits and number of BP recordings per visit on which BP results were based were reported in <15% of papers. The criteria for the diagnosis of hypertension were described in 72.7% (48/66) of the studies. The used definitions of improvement of BP control after adrenalectomy were variable, with 84.8% of the studies not providing any quantitative criteria to define reduction in BP. We conclude that the quality of reporting on BP control after adrenalectomy for primary aldosteronism shows substantial deficiencies and inconsistencies, thus impacting negatively on accurate assessment of effects of adrenalectomy on BP control. Future studies should adhere to accepted recommendations of correct BP measurement and should provide detailed description of the methods used for BP measurement.

Abstract 026: Attended Versus Unattended Blood Pressure Measurement in Patients With Cardiovascular Disease: Does It Matter?

Introduction: Nearly one half of the subjects in SPRINT had their blood pressure (BP) measured absent an observer (unattended), whereas most prior trials have used attended measurement. This has created controversy in interpreting the relationship between achieved systolic BP (SBP) and outcomes in SPRINT. Accordingly, we prospectively examined the difference between attended and unattended office SBP measured using the same automated device used in SPRINT among patients with documented CV disease. Methods: We randomized patients attending a routinely scheduled cardiology clinic visit to have their BP measured using an attended, followed by an unattended method, or vice versa, after a controlled rest period. All study BP measurements were obtained in triplicate using the automated Omron HEM-907XL BP monitor, and averaged. The outcome of interest was the difference in SBP between the two measurement techniques. At the same visit, we obtained a routinely measured office BP from the medical record, and compared with attended and unattended measurements. Results: A total of 102 patients were enrolled, mean age was 63 years, 48% (49 of 102) men and 75% (76 of 102) were Caucasian. The mean attended and unattended SBP was 125.4 ± 20.4 and 122.6 ± 21.0 mm Hg, respectively. The mean SBP recorded by the clinic nursing staff was 130.6 ± 23.6 mm Hg. On average, the attended SBP was 2.7 mmHg higher than the unattended measurement (P=0.0002, 95% CI 1.3 to 4.1). The clinic staff SBP measurement was 5.2 mmHg higher than the attended SBP (P=0.0003, 95% CI 2.4 to 8.0) and 8.0 mmHg higher than the unattended SBP (P&lt;0.0001, 95% CI 5.4 to 10.5). Conclusion: Among CVD patients being evaluated in a cardiology clinic, there is only a small (~3 mmHg) but statistically significant difference between attended and unattended automated SBP. More importantly, the routine office measured SBP was significantly higher than either the attended or unattended SBP. Our findings suggest that observing the BP measurement in patients with established CVD affects the BP, but much less than previously suggested. Factors such as measurement timing and non-standardized measurement technique are likely to have a larger impact on BP measurement than observer attendance.