Differences in Blood Pressure, Retinal Blood Flow, and Intraocular Pressure in open angle glaucoma patients of African Descent versus European Descent

Abstract

Purpose : To investigate the relationships between systemic blood pressure with retinal capillary blood flow and intraocular pressure in open angle glaucoma (OAG) patients of European (ED) and African descent (AD).

Methods : 41 OAG patients (34 ED, 7 AD) were assessed for blood pressure (BP) by an automated ambulatory blood pressure monitor: systolic blood pressure (SBP-SYS), diastolic blood pressure (BP-DYS) were measured, and the mean arterial pressure (MAP) was calculated. Heidelberg Retinal Flowmetry (HRF) was used to measure peripapillary retinal capillary blood flow. Intraocular pressure (IOP) was measured with Goldmann applanation tonometry. Ocular perfusion pressure (OPP) was calculated from BP and IOP (OPP=(2/3)(MAP - IOP); SOPP=BP-SYS–IOP; DOPP=BP-DYS–IOP). Pearson correlation and multivariate linear regression analysis were performed.

Results : In OAG patients of AD, HRF superior blood flow was negatively and significantly correlated with BP-SYS (r=-0.895, p=0.004) and MAP (r=-0.894 p=0.004), and HRF inferior avascular zone positively correlated with BP-DYS (r=0.810 p=0.024). These correlations were weaker and not significant in ED patients, leading to a significant difference between race groups (p=0.025, 0.037, and 0.027 respectively). IOP was significantly and positively correlated with BP-SYS (r=0.866, p=0.009) and SOPP (r=0.760 p=0.047) in OAG patients of AD, leading to a significant difference between race groups (p=0.014 and p=0.019 respectively).

Conclusions : The relationship between BP, retinal capillary blood flow and IOP is statistically different in OAG patients of AD compared to OAG patients of ED.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.