Long-term HbA1c Variability and Treatment Outcomes of Intravitreal Injection in Diabetic Macular Edema

ABSTRACT

Purpose@#To evaluate the association between long-term glycated hemoglobin A (HbA1c) variability and treatment outcomes ofanti-vascular endothelial growth factor (VEGF) injection in diabetic macular edema patients. @*Methods@#The medical records of 49 eyes (38 patients) that received anti-VEGF injection for diabetic macular edema were reviewedretrospectively. Best-corrected visual acuity (BCVA) and central macular thickness (CMT) before injection and at onemonth and six months after injection were analyzed. HbA1c variability (HbA1c coefficient of variation [CV]) was calculated usingthe HbA1c results from the year prior to (before) and the year after injection and compared with clinical results. @*Results@#In the group with a low mean HbA1c level before injection, the group with lower HbA1c CV showed greater reduction inmacular edema one month after injection (low HbA1c CV, 122.4 ± 123.2 μm versus high HbA1c CV, 5.2 ± 37.0 μm, p= 0.027).In the group with high mean HbA1c, there was no significant difference between HbA1c variability and clinical features. In a multivariateanalysis, the factor related to the reduction of macular edema was initial CMT (one month adjusted hazard ratio (aHR)0.5, p< 0.001; six months aHR 0.3, p= 0.023). The factor associated with visual gain was initial visual acuity (LogMAR) (onemonth aHR 0.4, p< 0.001; six months aHR 0.4, p< 0.001). The association between mean HbA1c or HbA1c variability and clinicaloutcome was not significant. @*Conclusions@#Unlike initial CMT or BCVA, mean HbA1c and HbA1c variability were not significantly associated with clinical outcomesof anti-VEGF injection in diabetic macular edema patients.