African and European Descent, Ocular Blood Flow and Glaucoma Progression

描述（由申请人提供）：本研究的目的是研究血管危险因素在解释为什么非洲人后裔（AD）与欧洲人后裔（ED）相比不成比例地受到青光眼的影响。研究表明，眼血流在某些个体青光眼损害的演变中起着重要作用。众所周知，阿尔茨海默病患者患系统性和脑血管疾病的几率增加。鉴于这些发现，本研究旨在探讨AD合并青光眼患者的眼灌注压和血流量异常是否导致AD人群中青光眼患病率和进展的差异。本研究涉及对印第安纳波利斯青光眼进展研究（IGPS）现有数据的精心设计的二次分析。这项研究的独特之处在于它是唯一一项长期前瞻性观察性研究

DESCRIPTION (provided by applicant): The objective of this study is to investigate the role of the vascular risk factors in explaining why individuals of African descent (AD) are disproportionately affected by glaucoma compared to individuals of European descent (ED). Studies have suggested that ocular blood flow plays a significant role in the evolution of glaucomatous damage in some individuals. It is also well known that persons of AD have an increased prevalence of systemic and cerebral vascular diseases. Given these findings, this study is designed to investigate if abnormal ocular perfusion pressure and blood flow in persons of AD with glaucoma contribute to the differences observed in the prevalence and progression of glaucoma in the AD population. This investigation involves a carefully designed secondary analysis of the existing data from the Indianapolis Glaucoma Progression Study (IGPS). This study is unique in that it is the only long- term prospective observational study that investigates the relationship between ocular perfusion and blood flow and structural and functional glaucoma progression. The 113 open-angle glaucoma patients enrolled in the IGPS receive a comprehensive ocular blood flow and perfusion parameters assessment alongside comprehensive clinical markers of glaucoma progression. Extensive clinical and hemodynamic measures were identically assessed at two identical baseline visits one week apart followed by biannual visits over a 3 year period. At each visit, patients underwent comprehensive testing including: multiple measures of intraocular pressure (Goldmann and Psacal), visual acuity, contrast sensitivity, ultrasonic corneal pachymetry of central corneal thickness, height, weight, body mass index, blood pressure, heart rate, medical history, visual field testing (using standard automated perimetry), Fourier domain Doppler optical coherence tomography (FD-OCT) with total retinal blood flow assessment, Stratus optical coherence tomography (OCT) structural imaging, Heidelberg retina tomography III, color Doppler imaging of the retrobulbar blood vessels, confocal scanning laser Doppler flowmetry of retinal capillaries, ocular perfusion pressure calculations, refraction, Pascal applanation (ocular pulse amplitude) and medical questionnaires. The proposed secondary data analysis will analyze the relationship between structural and functional disease progression and ocular perfusion pressure and blood flow, and investigate the differences between AD and ED glaucoma populations. Identifying distinct differences in vascular parameters between individuals of AD and ED will provide valuable insight into determining the mechanisms of disparity in glaucoma prevalence and progression in persons of AD. PUBLIC HEALTH RELEVANCE: The objective of this study is to explore the role of vascular risk factors in explaining the mechanisms behind the disparity of glaucoma in persons of African descent compared to those of European descent. The known increased prevalence of systemic vascular disease in the African descent population suggests that deficiencies in ocular perfusion pressure and blood flow may have a significant role in explaining these inequalities. Our unique secondary analysis of the Indianapolis Glaucoma Progression Study data which includes comprehensive ocular perfusion pressure, blood flow, retinal and optic nerve structure, visual function and their relationship to disease progression has the potential to elucidate, for the firs time, the reason for the disparity in glaucomatous disease between those of African descent and European descent.