Registered Nurse, MScN PHCNP student University Of Ottawa Greely, Ontario, Canada
Background: Hypertension prevalence is significantly higher in individuals with obesity; however, routine blood pressure (BP) monitoring practices in this population are inconsistent, partly due to anatomical measurement challenges. Despite known inaccuracies from undersized cuffs, the impact of appropriately sized cuffs and their shapes requires further clarity. This study systematically examined observational data to identify trends and factors influencing BP measurement accuracy related to cuff shape and measurement methods in individuals with obesity.
METHODS AND RESULTS: A systematic literature review was conducted following PRISMA guidelines, focusing on studies published within the last 10 years. Electronic databases including Scopus, PubMed, and CINAHL yielded 1,635 studies; 18 observational studies met inclusion criteria after screening. Selected studies compared BP readings from manual and automated devices in individuals with obesity, evaluating cuff shapes (cylindrical vs. conical) and measurement locations (upper arm, forearm, wrist).
The reviewed studies collectively demonstrated considerable variability in BP measurements attributable to multiple interrelated factors. Anatomical characteristics, notably arm conicity, circumference, and skinfold thickness, were key factors influencing measurement accuracy. Cylindrical cuffs, despite being appropriately sized, demonstrated systolic BP overestimation during manual auscultation, particularly at arm circumferences greater than 42 cm when compared to troncoconical cuffs due to inadequate conformity to conical-shaped arms. When comparing automated oscillometric device measurements, most studies demonstrated a trend toward systolic BP underestimation at the upper arm relative to intra-arterial measurements, whereas forearm measurements showed less bias, often trending towards mild underestimation. The underestimation observed with automated upper-arm devices may be explained by the damping effect, whereby increased soft tissue thickness may absorb pressure waves, generating falsely low readings. This contrasts with manual measurements, which showed systolic BP overestimation, illustrating distinct interactions between measurement techniques and anatomical features in obesity. Forearm measurement accuracy further improved with the use of conical-shaped cuffs, indicating the importance of cuff-arm conformity. Wrist measurements, while convenient in cases of difficult arm cuff placement, demonstrated variability due to device-dependent accuracy and sensitivity to positioning, limiting their reliability in some populations.
Conclusion: The findings emphasize that accurate BP measurement in individuals with obesity depends not only on cuff size but also on cuff shape, cuff placement, measurement device, and anatomical characteristics of the arm. Inconsistent practices, such as assessing BP at different measurement sites for the same individual, may further compromise the accurate assessment of BP trends and hypertension management. Further research remains essential to refine device validation and measurement techniques tailored specifically for individuals with obesity.
