3.5 CUFF BLOOD PRESSURE IS PROGRESSIVELY MORE BIASED WITH INCREASING AGE: INDIVIDUAL PARTICIPANT LEVEL ANALYSIS FROM THE INSPECT CONSORTIUM

Objectives: Accurate blood pressure (BP) measurement is critical for appropriate hypertension diagnosis and management. Aortic BP represents pressure loading on vital organs and this can be approximated using upper arm cuff BP. With advancing age, cuff systolic BP (SBP) increases and diastolic BP (DBP) decreases (widening pulse pressure [PP]), but whether age may influence cuff BP compared with invasive BP is unknown and was the aim of this study. Methods: Cuff BP was measured simultaneously, or near-simultaneously, with invasive aortic BP during catheterization in 1696 individuals within the INSPECT consortium (an international collaboration comprising data from 31 studies and 19 different cuff BP devices [17 oscillometric, 2 mercury sphygmomanometry]). Differences in cuff and invasive BP were assessed using mixed models. Results: Subjects were aged 63.3 ± 10.6 years and 32% female. Cuff SBP overestimated invasive aortic SBP in those aged 40–49, but with increasing age there was a progressive increase in the underestimation of aortic SBP (Table). Conversely, cuff DBP systematically overestimated aortic DBP, increasingly with age. Thus, there was a progressively higher error (underestimation) in cuff PP with older age. Adjusting models for sex, mean arterial pressure, heart rate and catheter type did not alter the findings, and no interactions between these parameters and age were found. Conclusion: Cuff BP is progressively more biased with increasing age, exposing older people to greater chance for misdiagnosis of risk related to BP. The findings highlight the need to improve cuff BP methods to ensure all people receive appropriate diagnosis and management of hypertension.