INTRODUCTION: Population monitoring and screening of blood pressure is an important part of any population health strategy. Qualified health workers are expensive and often unavailable for screening. Non-health workers with electronic blood pressure monitors are increasingly used in community-based research. This approach is unvalidated. In a poor, urban community we compared blood pressure measurements taken by non-health workers using electronic devices against qualified health workers using mercury sphygmomanometers.
METHOD: Fifty-six adult volunteers participated in the research. Data were collected by five qualified health workers, and six non-health workers. Participants were randomly allocated to have their blood pressure measured on four consecutive occasions by alternating a qualified health worker with a non-health worker. Descriptive statistics and graphs, and mixed effects linear models to account for the repeated measurement were used in the analysis.
RESULTS: Blood pressure readings by non-health workers were more reliable than those taken by qualified health workers. There was no significant difference between the readings taken by qualified health workers and those taken by non-health workers for systolic blood pressure. Non-health workers were, on average, 5-7 mmHg lower in their measures of blood pressure than the qualified health workers (95%HPD: -2.9 to -10.0) for diastolic blood pressure.
CONCLUSION: The results provide empirical evidence that supports the practice of non-health workers using electronic devices for BP measurement in community-based research and screening. Non-health workers recorded blood pressures that differed from qualified health workers by no more than 10 mmHg. The approach is promising, but more research is needed to establish the generalisability of the results.
KEYWORDS: Malaysia; blood pressure; community workers; hypertension; measurement; screening
Study site: urban, low-income community, of the Klang Valley near Kuala Lumpur, Malaysia
Device: Mercury sphygmomanometers (Spirit brand, model number CK-101C), electronic, automatic blood pressure monitors (Omron brand model HEM-7203)
A study was undertaken to assess the accuracy of the Omron HEM-907 blood pressure measuring device for use in community studies. A modified version of the British Hypertension Society (BHS) and American Association for the Advancement Medical Instrumentation (AAMI) protocol for measuring the accuracy of a blood pressure measuring device was used. A total of 104 subjects were recruited from two clinics. Observer-observer agreement for readings within the 5 mmHg was good; 80.8% and 84.6% of systolic blood pressure (SBP) and diastolic blood pressure (DBP) agreement respectively. Of the two, the better observer-device agreement readings within the 5 mmHg were 66.4% and 50.0% for SBP and DBP respectively, giving an overall grade B. The mean differences and standard deviation of the differences were within < or =5 mmHg with a standard deviation (SD) of < or =8 mmHg. The Omron HEM-907 satisfied both the AAMI and BHS protocols for accuracy for a non-invasive blood pressure monitoring device using single observer readings.
Study site: Klinik Kesihatan Shah Alam, Selangor; Hypertension clinic, Hospital Kuala Lumpur, Malaysia
Device: Standard device: mercury sphygmomanometer (brand?); test device: oscillometric automated electronic BP monitor (Omron HEM-907).
The Bland-Altman method is the most popular method used to assess the agreement of medical instruments. The main concern about this method is the presence of proportional bias. The slope of the regression line fitted to the Bland-Altman plot should be tested to exclude proportional bias. The aim of this study was to determine whether the overestimation of bias in the Bland-Altman analysis is still present even when the proportional bias has been excluded.
A self-measured home blood pressure (BP)-guided strategy is an effective practical approach to hypertension management. The Asia BP@Home study is the first designed to investigate current home BP control status in different Asian countries/regions using standardized home BP measurements taken with the same validated home BP monitoring device with data memory. We enrolled 1443 medicated hypertensive patients from 15 Asian specialist centers in 11 countries/regions between April 2017 and March 2018. BP was relatively well controlled in 68.2% of patients using a morning home systolic BP (SBP) cutoff of <135 mm Hg, and in 55.1% of patients using a clinic SBP cutoff of <140 mm Hg. When cutoff values were changed to the 2017 AHA/ACC threshold (SBP <130 mm Hg), 53.6% of patients were well controlled for morning home SBP. Using clinic 140 mm Hg and morning home 135 mm Hg SBP thresholds, the proportion of patients with well-controlled hypertension (46%) was higher than for uncontrolled sustained (22%), white-coat (23%), and masked uncontrolled (9%) hypertension, with significant country/regional differences. Home BP variability in Asian countries was high, and varied by country/region. In conclusion, the Asia BP@Home study demonstrated that home BP is relatively well controlled at hypertension specialist centers in Asia. However, almost half of patients remain uncontrolled for morning BP according to new guidelines, with significant country/regional differences. Strict home BP control should be beneficial in Asian populations. The findings of this study are important to facilitate development of health policies focused on reducing cardiovascular complications in Asia.