Abstract
Purpose :
Despite progress in therapeutic options, diabetic macular edema (DME) remains a significant cause of vision loss, especially among diabetic patients who seek care from safety net hospitals. A retrospective observational cross-sectional case series at a county hospital system in Los Angeles, California was performed to identify clinical factors associated with significant change in central macular thickness (CMT) after dexamethasone intravitreal implant treatment.
Methods :
Twenty five diabetic patients (mean [SD] age, 61.4 [6.92] years; 63% female) who received dexamethasone intravitreal implants for DME recalcitrant to bevacizumab between November 2016 - November 2017 were included in this study. CMT measurements were taken from macular spectral domain OCTs, and patients were categorized as responders to dexamethasone implant treatment if they exhibited a decrease in central macular thickness of greater than 50μm. Baseline and average values for HgA1c, LDL, creatinine, GFR, systolic and diastolic blood pressure were collected from the electronic medical record. Visual acuity, fluorescein angiographic features, and prior treatments for DME were also noted.
Results :
Baseline demographics of subjects with DME were comparable between responders and non-responders, and mean CMT measurements prior to dexamethasone implant treatment were 515μm and 381μm respectively (p=0.046). Responders had a mean decrease of 167μm compared to a mean decrease of 7.7μm in non-responders (p=0.003). Responders were found to have lower HgA1c values, systolic blood pressure, LDL and creatinine levels compared to nonresponders. Nonresponders were found to have a higher average systolic blood pressure 151mmHg vs. 137mmHg (p=0.010) and a higher baseline creatinine level 2.23mg/dL vs. 1.07mg/dL (p=0.047).
Conclusions :
High average systolic blood pressure and elevated baseline creatinine levels are associated with reduced responsiveness to dexamethasone intravitreal implant. Patients with DME recalcitrant to bevacizumab but responsive to dexamethasone implant are more likely to have severe edema. Further study is needed to determine the most effective therapeutic strategy in this subset of DME patients.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.