Relationship of blood pressure measured in the calf with arm blood pressure and arterial stiffness: a general population study

Abstract

Aim: Leg blood pressure (BP) measurement is needed when arm BP evaluation is not feasible, and calf BP, especially when measured in standing position, may have greater association with cardiovascular remodeling than arm BP. This study evaluated the relationship between calf and arm BP, and investigated whether calf BP would be superior to arm BP in predicting increased arterial stiffness [pulse wave velocity (PWV) > 10 m/s]. Methods: We evaluated clinical and laboratory characteristics, BP measurements, and PWV in 1397 individuals resident in Baependi, Brazil, between 2017 and 2019. Arm BP was measured in the seated and supine positions while calf BP was measured in supine and standing positions using digital oscillometric devices. Carotid–femoral PWV was measured using a noninvasive mechanotransducer. Results: The sample had 62.7% females, age = 48.1 ± 15.4 years and 8.4% with PWV >10 m/s. Results of linear regression analysis showed that BP values of 140/90 mmHg measured in the arm in supine and seated position were equivalent to calf supine BP values of 164/81 mmHg and 166/78 mmHg and calf standing BP values of 217/137 mmHg and 221/137 mmHg, respectively. Calf-arm BP differences were associated with age, glomerular filtration rate, body mass index, smoking, low-density lipoprotein-cholesterol, diabetes and height. Furthermore, stepwise logistic regression analysis revealed that arm supine systolic BP, but not calf BP measurements, was independently associated with increased arterial stiffness. Conclusion: Thresholds of ≈165/80 mmHg and ≈220/135 mmHg could be used for diagnosing hypertension when only calf measurements in supine and standing positions, respectively, are available. Conversely, calf BP was not superior to arm BP in predicting increased arterial stiffness.