Can validated wrist devices with position sensors replace arm devices for self-home blood pressure monitoring? A randomized crossover trial using ambulatory monitoring as reference

BACKGROUND: Electronic devices that measure blood pressure (BP) at the arm level are regarded as more accurate than wrist devices and are preferred for home BP (HBP) monitoring. Recently, wrist devices with position sensors have been successfully validated using established protocols. This study assessed whether HBP values measured with validated wrist devices are sufficiently reliable to be used for making patient-related decisions in clinical practice. METHODS: This randomized crossover study compared HBP measurements taken using validated wrist devices (wrist-HBP, Omron R7 with position sensor) with those taken using arm devices (arm-HBP, Omron 705IT), and also with measurements of awake ambulatory BP (ABP, SpaceLabs), in 79 subjects (36 men and 43 women) with hypertension. The mean age of the study population was 56.7 +/- 11.8 years, and 33 of the subjects were not under treatment for hypertension. RESULTS: The average arm-HBP was higher than the average wrist-HBP (mean difference, systolic 5.2 +/- 9.1 mm Hg, P < 0.001, and diastolic 2.2 +/- 6.7, P < 0.01). Twenty-seven subjects (34%) had a > or =10 mm Hg difference between systolic wrist-HBP and arm-HBP and twelve subjects (15%) showed similar levels of disparity in diastolic HBP readings. Strong correlations were found between arm-HBP and wrist-HBP (r 0.74/0.74, systolic/diastolic, P < 0.0001). However, ABP was more strongly correlated with arm-HBP (r 0.73/0.76) than with wrist-HBP (0.55/0.69). The wrist-arm HBP difference was associated with systolic ABP (r 0.34) and pulse pressure (r 0.29), but not with diastolic ABP, sex, age, arm circumference, and wrist circumference. CONCLUSIONS: There might be important differences in HBP measured using validated wrist devices with position sensor vs. arm devices, and these could impact decisions relating to the patient in clinical practice.Measurements taken using arm devices are more closely related to ABP values than those recorded by wrist devices. More research is needed before recommending the widespread use of wrist monitors in clinical practice.American Journal of Hypertension doi:10.1038/ajh.2008.176American Journal of Hypertension (2008); 21, 7, 753-758. doi:10.1038/ajh.2008.176.     

Measuring orthostatic hypotension with the Finometer device: is a blood pressure drop of one heartbeat clinically relevant?

OBJECTIVE: The role of orthostatic hypotension in falls in older people is generally accepted. Because of the high degree of intra- and interobserver variability in conventional measurements of orthostatic hypotension, application of continuous measurement systems has been proposed. The clinical relevance of a blood pressure drop lasting one heartbeat, however, is unknown. We therefore investigated which time average of continuous-finger-blood-pressure measurement (Finometer) showed the best association between orthostatic hypotension and falls. This was also compared with conventional sphygmomanometer measurements. METHODS: In 217 geriatric outpatients supine and standing (finger) blood pressure to diagnose orthostatic hypotension was monitored with Finometry (beat-to-beat and 1, 5, 10, 15, 20 and 30 s averages) and sphygmomanometry. History of fall incidents (previous year) was registered. RESULTS: The best association (C=0.22, P=0.003) with falls history was found for the 5-s average of Finometry, whereas falls and orthostatic hypotension assessed by sphygmomanometry did not correlate. The odds ratio of a fall according to orthostatic hypotension using the 5-s average was 2.54 (95% CI: 1.37 to 4.71). CONCLUSIONS: Orthostatic hypotension and falls are correlated when using Finometry, with the best association found when using 5-s averages. As the etiology of falls is often multifactorial, orthostatic hypotension and falls are poorly correlated, irrespective of the method or time average that is applied.     

Can a radioimmunoassay kit be developed for accurate detection of the S protein of severe acute respiratory syndrome coronavirus 2?

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at the end of 2019 spread worldwide within only a few months. The screening and timely isolation of infected individuals have been regarded as an effective means of epidemic prevention and control. Therefore, effective screening of infected individuals plays a vital role in epidemic prevention and control. At present, reverse transcription-polymerase chain reaction (RT–PCR) is the main method for the in vitro detection of SARS-CoV-2. However, RT–PCR requires certified laboratories, expensive equipment, and trained technicians. Therefore, it is necessary to develop simpler and more convenient methods. Some studies have shown that the PepKAA peptide has a high affinity for the S protein of SARS-CoV-2. The tyrosine in PepKAA is labeled with ¹²⁵I and used to design a radioimmunoassay kit for the detection of the S protein of SARS-CoV-2, which is of great significance for the early diagnosis of COVID-19.     

How many times should blood pressure be measured at home for better prediction of stroke risk? Ten-year follow-up results from the Ohasama study

OBJECTIVE: To determine the optimum number of blood pressure self-measurements taken at home (home blood pressure) in relation to their predictive value for stroke risk. METHODS: We obtained more than 14 measurements of home blood pressure from 1491 people aged >or=40 years without a history of stroke in the general population in Japan, and followed them up after a mean period of 10.6 years. The prognostic significance of blood pressure for stroke risk was examined using the Cox proportional hazards regression model, which was adjusted for possible confounding factors. RESULTS: The predictive value of home blood pressure increased progressively with the number of measurements, showing the highest predictive value with the average of whole measurements (mean = 25 measurements, 35% increase in the risk of stroke per 10 mmHg elevation in blood pressure). The initial home blood pressure values (one measurement) showed a significantly greater relation with stroke risk than conventional blood pressure values (mean of two measurements) (19/8% increase in the risk of stroke per 10 mmHg elevation in initial home/conventional systolic blood pressure values, respectively). CONCLUSIONS: There was no threshold for the number of home blood pressure measurements within the range of 1-14 measurements for increasing the predictive power of stroke risk, suggesting that as many measurements as possible, preferably more than 14 measurements, is recommended for better prediction of stroke risk. It should be emphasized that home blood pressure has a stronger predictive power than does conventional blood pressure, even for a lower number of measurements.     

A comparison of a continuous noninvasive arterial pressure (CNAP™) monitor with an invasive arterial blood pressure monitor in the cardiac surgical ICU

Accurate measurement and display of arterial blood pressure is essential for rational management of adult cardiac surgical patients. Because of the lower risk of complications, noninvasive monitoring methods gain importance. A newly developed continuous noninvasive arterial blood pressure (CNAP?) monitor is available and has been validated perioperatively. In a prospective study we compared the CNAP? monitoring device with invasive arterial blood pressure (IAP) measurement in 30 patients in a cardiac surgical Intensive Care Unit (ICU). Patients were either mechanically ventilated or spontaneously breathing, with or without inotropes. CNAP? was applied on two fingers of the hand contralateral to the IAP monitoring catheter. Systolic, diastolic and mean pressure data were recorded every minute for 2 h simultaneously for both IAP and CNAP?. Statistical analysis included construction of mountain plot and Bland Altman plots for assessing limits of agreement and bias (accuracy) calculation. Three thousand and six hundred pairs of data were analyzed. The CNAP? systolic arterial pressure bias was 10.415 mmHg and the CNAP? diastolic arterial pressure bias was -5.3386 mmHg; the mean arterial pressure (MAP) of CNAP? was close to the MAP of IAP, with a bias of 0.03944 mmHg. The Bland Altman plot showed a uniform distribution and a good agreement of all arterial blood pressure values between CNAP? and IAP. Percentage within limits of agreement was 94.5%, 95.1% and 99.4% for systolic, diastolic and MAP. Calculated limits of agreement were -4.60 to 25.43, -13.38 to 2.70 and -5.95 to 6.03 mmHg for systolic, diastolic and mean BP, respectively. The mountain plot showed similar results as the Bland Altman plots. We conclude CNAP? is a reliable, noninvasive, continuous blood pressure monitor that provides real-time estimates of arterial pressure comparable to those generated by an invasive arterial catheter system. CNAP? can be used as an alternative to IAP.     

Can ambulatory arterial blood pressure monitoring taken in the 4th month of pregnancy in normotensive primaparas predict the appearance of a fetomaternal event? Results of a French multicenter study. Report of 170 cases]

OBJECTIVE: To evaluate in a primigravid normotensive population the predictive value of outcome of the ambulatory blood pressure monitoring (ABPM) at the 4th month of pregnancy. DESIGN AND METHODS: A longitudinal observational study was carried out in 174 primigravid normotensives free from proteinuria and glycosuria during the first trimester. These women underwent an ABPM (Spacelabs 90207) at 17 +/- 3 weeks gestation and were then followed up throughout pregnancy for the identification of outcome: gestational hypertension (blood pressure > or = 140/80), proteinuria, hyperuricemia, preterm delivery, birth weight < 10th percentile, need for admission to the special care neonatal unit (SCNU). STATISTICS: Non parametric tests, ROC curves. RESULTS: Of the 174 women, 170 had sufficient readings to be considered for analysis. Pre-eclampsia occurred in 5 cases (3%), gestational hypertension in 27 (16%), proteinuria in 20 (12%), hyperuricemia in 2 (1%), preterm delivery in 11 (6%), low birth weight in 9 (5%) and admission to SCNU in 16 (9%). Women with gestational hypertension already exhibited at the 4th month, both ambulatory and clinical blood pressure (BP) higher than did normotensive women (respectively: 117 +/- 7/70 +/- 5 vs 110 +/- 7/65 +/- 6 mmHg, p < 0.0001 for 24-hour ABPM, and 124 +/- 8/76 +/- 7 vs 117 +/- 10/70 +/- 9 mmHg, p < 0.005 for clinical BP). There was a non significative trend for both ambulatory and clinical values to be slightly higher in the setting of preterm delivery, proteinuria and admission to SCNU and in contrast to be slightly lower in case of low birth weight. The occurrence of one outcome or more (49 outcomes, low birth weight excepted), was associated with significantly higher ambulatory and clinical BP levels (114 +/- 7/68 +/- 6 vs 111 +/- 7/65 +/- 5 mmHg, p < 0.009 for ABPM, and 121 +/- 9/74 +/- 8 vs 117 +/- 9/70 +/- 8 mmHg, p < 0.007 for clinical BP). Positive and negative predictive values for the outcome of gestational hypertension were respectively for systolic ambulatory BP of 28% and 95% using a cut off value of 115 mmHg and for systolic clinical BP of 26% and 97% using a cut-off value of 120 mmHg. CONCLUSION: ABPM in a normotensive primigravid population at 17 weeks of gestation is not a better predictor of outcome, even of gestational hypertension, than clinical measurement.     

Can combining different risk interventions into a single formulation contribute to improved cardiovascular disease risk reduction? Rationale and design for an international, open-label program to assess the effectiveness of a single pill (amlodipine/atorvastatin) to attain recommended target levels for blood pressure and lipids (The JEWEL Program)

BACKGROUND: In order to prevent cardiovascular events, it is essential to effectively manage overall risk of cardiovascular disease. However, despite guideline recommendations to this effect, current management of the major, modifiable cardiovascular risk factors such as hypertension and dyslipidemia is disconnected and patient adherence to therapy is poor. This is particularly important for patients with multiple cardiovascular risk factors, who are often prescribed multiple medications. The JEWEL study program will investigate the use of single-pill amlodipine/atorvastatin as a strategy to improve management of these patients. METHODS: The JEWEL program consists of two 16-week, international, open-label, multicenter, titration-to-goal studies in patients with hypertension and dyslipidemia. The 2 studies differ based on country of enrollment and certain tertiary endpoints, but the overall designs are very similar. Patients have been enrolled from 255 centers across Canada and 13 European countries. The study is designed to assess the efficacy, safety, and utility of amlodipine/atorvastatin single-pill therapy in a real-world setting. Patients will be initiated at a dose of amlodipine 5 mg/atorvastatin 10 mg, unless previously treated, and will be uptitrated as necessary. The primary efficacy parameter is the percentage of patients, at different levels of cardiovascular risk, achieving country-specific guideline-recommended target levels for blood pressure and lipids. A secondary analysis of efficacy measured attainment of the same single goal for blood pressure across all study participants (JEWEL I and II) and the same single goal for LDL-C across all study participants (JEWEL I and II). The program will utilize a newly developed questionnaire to gain better understanding of participants' beliefs and behaviors towards medical treatment of their multiple risk factors. Approximately 2850 patients will be enrolled in the program, which is due to be completed in August 2005. CONCLUSION: The JEWEL program will assess the effectiveness of a single pill (amlodipine/atorvastatin) in targeting the two principal risk factors for cardiovascular disease simultaneously to achieve nationally applicable treatment targets in a routine clinical practice setting.