Effect of BMI on Central Arterial Reflected Wave Augmentation Index, Toe-Brachial Index, Brachial-Ankle Pulse Wave Velocity and Ankle-Brachial Index in Chinese Elderly Hypertensive Patients with Hemorrhagic Stroke

Abstract

Background: Hypertensive cerebral hemorrhage seriously endangers the health of the elderly. However, the relationship between obesity and arterial elasticity in hypertensive cerebral hemorrhage remains to be clarified. The purpose of our study is to explore the associations between body mass index (BMI) and central arterial reflected wave augmentation index (cAIx), toe-brachial index (TBI), brachial-ankle pulse wave velocity (baPWV), and ankle-brachial index (ABI) in the elderly hypertensive patients with hemorrhagic stroke.

Materials and methods: A total of 502 elderly hypertensive patients with hemorrhagic stroke and 100 healthy controls were collected. According to the BMI, patients were divided into normal BMI, overweight, obesity, and obese groups. The multivariate logistic regression model was used to establish a risk model for elderly hypertensive hemorrhagic stroke.

Results: Compared with the normal BMI group, systolic blood pressure (SBP), diastolic blood pressure (DBP), cAIx, and baPWV in the abnormal BMI group were significantly increased (P < 0.05), while TBI and ABI were significantly decreased (P < 0.05). Logistic regression showed that BMI (OR = 1.031, 95%CI: 1.009-1.262), cAIx (OR = 1.214, 95%CI: 1.105-1.964), TBI (OR = 0.913, 95%CI: 0.885-0.967), baPWV (OR = 1.344, 95%CI: 1.142-2.147), and ABI (OR = 0.896, 95%CI: 0.811-0.989) are important factors for the occurrence of hemorrhagic stroke in the elderly hypertensive patients. ROC curve analysis showed that the AUC of cAIx, TBI, baPWV, ABI, and BMI were 0.914, 0.797, 0.934, 0.833, and 0.608, respectively. The final prediction model of hemorrhagic stroke elderly hypertensive patients was Y_(P)= 65.424 + 0.307(cAIx) - 13.831(TBI) + 0.012(baPWV) - 0.110(ABI) + 0.339(BMI).

Conclusions: Obesity is associated with decreased arterial elasticity. Therefore, reasonable weight management of the elderly may be of great significance for reducing the risk of hemorrhagic stroke in patients with hypertension.

Keywords: Ankle-brachial index; Body mass index; Brachial-ankle pulse wave velocity; Central arterial reflected wave augmentation index; Hemorrhagic stroke; Hypertension; Toe-brachial index.