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Abstract

In the Beaver Dam Eye Study, blood pressure emerged as a risk factor for incident age-related macular degeneration (AMD) only after 10 years of observation of the cohort, suggesting that direct deleterious effects either are slow to manifest or be detected. 1 Klein R. Klein B.E.K. Tomany S.C. Cruickshanks K.J. The association of cardiovascular disease with the long-term incidence of age-related maculopathy: the Beaver Dam Eye Study. Ophthalmology. 2003; 110: 1273-1280 Abstract Full Text Full Text PDF PubMed Scopus (133) Google Scholar Thus it is not surprising that blood pressure was not found to be positively associated with early AMD in the cross-sectional Women’s Health Initiative Sight Examination Study. 2 Klein R. Yingzi D. Klein B.E.K. et al. Cardiovascular disease, its risk factors and treatment, and age-related macular degeneration: Women’s Health Initiative Eye Exam Ancillary Study. Am J Ophthalmol. 2007; 143: 473-483 Abstract Full Text Full Text PDF PubMed Scopus (103) Google Scholar However, in the Beaver Dam Eye Study, a strong, statistically significant association of pulse pressure to incident AMD was found earlier than systolic or diastolic blood pressure, suggesting that it may be more important than either. 3 Klein R. Klein B.E.K. Jensen S.C. The relation of cardiovascular disease and its risk factors to the 5-year incidence of age-related maculopathy: the Beaver Dam Eye Study. Ophthalmology. 1997; 104: 1804-1812 Abstract Full Text PDF PubMed Scopus (155) Google Scholar Pulse pressure is a marker of the rigidity of the blood vessels from loss of elasticity. It is usually calculated as the difference between systolic and diastolic blood pressure. As people age, many develop higher systolic blood pressure and lower diastolic blood pressure, resulting in greater pulse pressure. Some people, especially those on antihypertensive treatment, may not demonstrate increased systolic blood pressure but have only decreased diastolic blood pressure. The relationship of this junctional change to stiffened blood vessels and the effect, if any, on AMD requires further systematic study. Sato and associates find that the severity of AMD is associated with monotonic increases in blood flow pulsatility in major arteries is consistent with our earlier findings of a relationship of pulse pressure with incident AMD in Beaver Dam. 4 Sato E. Feke G.T. Menke M.N. McMeel J.W. Retinal hemodynamics in patients with age-related macular degeneration. Eye. 2006; 20: 697-702 Crossref PubMed Scopus (47) Google Scholar We appreciate the comments of Dr Feke and hope this stimulates further research into understanding the role of age-related hemodynamic changes in the pathogenesis of AMD. Cardiovascular Disease, its Risk Factors and Treatment, and Age-related Macular Degeneration: Women’s Health Initiative Sight Exam Ancillary StudyAmerican Journal of OphthalmologyVol. 144Issue 3PreviewIn the recent article by Klein and associates1 addressing the association of cardiovascular disease (CVD) and its risk factors and treatment with age-related macular degeneration (AMD), among the findings reported were that elevated systolic blood pressure (SBP) was positively associated with the presence of soft drusen and inversely associated with the presence of retinal pigment epithelium depigmentation, lesions that are hallmarks of early AMD. They also found an inverse association between elevated SBP and the presence of exudative AMD. Full-Text PDF