Agreement between the Takeda UA-731 automatic blood pressure measuring device and the manual mercury sphygmomanometer: an assessment under field conditions in Newcastle upon Tyne, UK

Sources of inaccuracy in the measurement of adult patients' resting blood pressure in clinical settings: a systematic review

BACKGROUND

To interpret blood pressure (BP) data appropriately, healthcare providers need to be knowledgeable of the factors that can potentially impact the accuracy of BP measurement and contribute to variability between measurements.

METHODS

A systematic review of studies quantifying BP measurement inaccuracy. Medline and CINAHL databases were searched for empirical articles and systematic reviews published up to June 2015. Empirical articles were included if they reported a study that was relevant to the measurement of adult patients' resting BP at the upper arm in a clinical setting (e.g. ward or office); identified a specific source of inaccuracy; and quantified its effect. Reference lists and reviews were searched for additional articles.

RESULTS

A total of 328 empirical studies were included. They investigated 29 potential sources of inaccuracy, categorized as relating to the patient, device, procedure or observer. Significant directional effects were found for 27; however, for some, the effects were inconsistent in direction. Compared with true resting BP, significant effects of individual sources ranged from -23.6 to +33 mmHg SBP and -14 to +23 mmHg DBP.

CONCLUSION

A single BP value outside the expected range should be interpreted with caution and not taken as a definitive indicator of clinical deterioration. Where a measurement is abnormally high or low, further measurements should be taken and averaged. Wherever possible, BP values should be recorded graphically within ranges. This may reduce the impact of sources of inaccuracy and reduce the scope for misinterpretations based on small, likely erroneous or misleading, changes.

Community-based blood pressure measurement by non-health workers using electronic devices: a validation study

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.

Low levels of cardiovascular risk factors and coronary heart disease in a UK Chinese population

OBJECTIVE

To compare the prevalence of cardiovascular risk factors and coronary heart disease in Chinese and Europid adults.

DESIGN

Population based, cross sectional survey.

SETTING

Newcastle upon Tyne, UK, 1991-93.

SUBJECTS

Altogether 380 Chinese and 625 Europid adults, aged 25-64 years.

MAIN OUTCOME MEASURES

Fasting lipid levels, blood pressure, body mass index (BMI), the proportions who smoked, and the prevalence of coronary heart disease based on the Rose angina questionnaire and major electrocardiographic abnormalities on resting 12 lead electrocardiogram (Minnesota codes 1.1-1.2). All figures were age adjusted to the 1991 England and Wales population.

RESULTS

Altogether 183 and 197 Chinese, and 310 and 315 Europid men and women respectively were seen. Compared with Europid men, Chinese men had a lower mean total cholesterol concentration (5.1 versus 5.6 mmol/l, p < 0.001) and LDL cholesterol (3.2 versus 3.6 mmol/l, p < 0.001); lower BMI values (23.8 versus 26.1 kg/m-2, p < 0.001); and smoked less (23% versus 35%, p < 0.01)). Compared with Europid women, Chinese women also had lower mean lipid levels (total cholesterol: 4.9 versus 5.4 mmol/l p < 0.001, LDL cholesterol: 2.8 versus 3.1 mmol/l p < 0.001); BMI values (23.5 versus 26.1 kg/m-2, p < 0.001); and far fewer were smokers (1.4% versus 33%, p < 0.001). Chinese women, however, had higher mean systolic (121 versus 117 mmHg, p > 0.05) and diastolic (75 versus 68 mmHg, p < 0.001) blood pressures. The prevalence of coronary heart disease was significantly lower in Chinese than Europid men (4.9% versus 16.6%, p < 0.001) but not significantly different in women (7.3% versus 11.1%, p = 0.16).

CONCLUSION

Strategies for UK Chinese are needed to maintain this favourable risk factor profile and prevent any potential increase in the risk of coronary heart disease associated with increasing acculturation.