Systolic blood pressure, choroidal thickness, and axial length in patients with myopic maculopathy

Abstract

Background: In the population-based Shihpai Eye Study, patients aged >65 years with myopic maculopathy were found to have higher systolic blood pressure. This finding deserved further exploration because this is the only correctable factor for preventing maculopathy in patients with high myopia. Therefore, we investigated the association between myopic maculopathy and systolic blood pressure, as well as other ocular parameters in this study.

Methods: A clinic-based, retrospective cross-sectional study at a medical center was conducted between February 2011 and October 2012. Patients with high myopia were included and medical charts were reviewed. High myopia was defined as axial length ≥26.5 mm in at least one eye. Myopic maculopathy was defined as the presence of lacquer cracks, focal areas of deep choroidal atrophy, diffuse chorioretinal atrophy, and macular choroidal neovascularization or geographic atrophy in the presence of high myopia. Systolic blood pressure measurements were collected, and fundus photography and optical coherence tomography were performed. Subfoveal choroidal thickness (SFCT) shown on optical coherence tomography was measured and recorded.

Results: The medical records of 187 high-myopic patients (87 without and 100 with maculopathy) were reviewed. Patients with maculopathy were older (56.96 years vs. 42.95 years, p < 0.01), had longer axial length (29.96 mm vs. 27.31 mm, p < 0.01), thinner SFCT (49.71 μm vs. 155.77 μm, p < 0.01), higher systolic blood pressure (132.28 mmHg vs. 125.31 mmHg, p < 0.05), greater prevalence of hypertension (31% vs. 16%, p < 0.05), and longer history of hypertension (2.34 years vs. 0.59 years, p < 0.01) compared to patients without maculopathy. After multivariate adjustment, SFCT and axial length were the only significant factors for maculopathy.

Conclusion: Thinner SFCT and longer axial length are significant risk factors for myopic maculopathy. Unlike previous epidemiological surveys, results of this clinic-based study suggested that systolic blood pressure is not a significant factor for maculopathy.

Keywords: axial length; choroidal thickness; high myopia; hypertension; myopic maculopathy.