Impact of Systemic Beta-Blocker Use and Need for Repeated Intravitreal Injections in Wet AMD Treated by Bevacizumab
To evaluate the effect of concomitant systemic therapy in patients with choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD) treated by intravitreal bevacizumab and to propose a mechanism for different interindividual response, the following retrospective, nonrandomized, single-center, consecutive interventional case series study was performed.
A total of 46 eyes from 46 patients with CNV secondary to AMD were treated by monthly intravitreal 1.25 mg bevacizumab injections on a pro re nata regime. Patients' files were revised and changes in Early Treatment Diabetic Retinopathy Study (ETDRS) best-corrected visual acuity (BCVA), central foveal thickness as determined by spectral domain optical coherence tomography (SD-OCT), number of injections performed, occurrence of severe adverse effects, and systemic concomitant medication were recorded. The effect of systemic medication on final BCVA, central foveal thickness and number of injections performed was evaluated.
It was reported that the most frequent systemic medications recorded were angiotensin-converting-enzyme inhibitors in 19 patients, beta-adrenergic blocking agents (n=18), nonsteroidal anti-inflammatory drugs (n=17), diuretics (n=16), calcium channel blockers (n=14), benzodiazepines (n=11), proton-pump inhibitors (n=9) and statins (n=8). A total of 32 patients had arterial hypertension and average follow-up was 25.1 months (standard deviation [SD]=8.9). Average gain in BCVA was 0.9 (SD=13.6) and –2.1 letters (SD=15.9) at 12 months and 24 months, respectively. It was noted that the average reduction in central foveal thickness was 111 µm (SD=54) and 105 µm (SD=71) at 12 months and 24 months, respectively. The average number of intravitreal injections required was 6.7 (SD=3.2). Furthermore, patients on treatment with systemic beta-adrenergic blocking agents required fewer intravitreal injections (5.2, SD=2.4 vs. 7.9, SD=3.4) and this difference was statistically significant (p=0.0068, multiple linear regression).
It was determined that concomitant systemic beta-adrenergic blocking agents treatment may reduce the need for repeated intravitreal injections of bevacizumab in patients with CNV associated with AMD.