Abstract
Purpose: :
The effectiveness of anti-VEGF therapy in neovascular age-related macular degeneration (AMD) is well documented, but the influence of AMD-risk factors on the clinical outcome has not been clarified. At present, the optimal frequency for VEGF inhibitor injections is under investigation. In an attempt to reduce the number of intravitreal injections and associated costs, there is a trend to use individual retreatment criteria based on the clinical outcome. In this study we investigated the influence of age, smoking and the current use of antihypertensive medication on the effectiveness of anti-VEGF treatment over a 24 month time period.
Methods: :
100 well-defined patients with exudative AMD (classified by fluorescein angiography) were included in this study. Subjects who underwent intravitreal anti-VEGF treatment with VA > 1.0 logMAR at baseline or incomplete data were rejected. Clinical data included best-corrected visual acuity (VA) (at baseline, 5-9 weeks after 3 injections / after the last injection) and number of injections received during the 24 month time period. All patients were interviewed with the help of a standard questionnaire including smoking habits and current medication.
Results: :
The study included 11 current smokers and 31 past smokers with a median of 23.5 pack/years. 72% currently used antihypertensive medication. The mean age at baseline was 77.5 ± 7 years. Mean VA at baseline was 0.65±0.26 logMAR. The mean change of VA after three injections was 0.0 logMAR (to 0.65±0.46) and after the last injection 0.15 logMAR (to 0.80±0.49). The more pack years a patient had smoked, the lower VA was after the last injection (tau = 0.18, p = 0.009). Patients using antihypertensive drugs had a significantly lower VA after the last injection (change: -0.01 logMAR vs. 0.21 logMAR p=0.045). Mean number of injections during an observational period of 24 months was 5.5 ±2.9. Older patients received fewer injections (tau = 0.15, p = 0.03). There was a trend between smoked cigarettes per day and numbers of injections received (tau = 0.12, p = 0.08).
Conclusions: :
Smoking is not only a major risk factor for the development of AMD but is also relevant for the effectiveness and cost of anti-VEGF treatment. This is a further argument in promoting smoking cessation to patients with AMD. The impact of hypertension and its treatment on anti-VEGF therapy requires further investigation.
Keywords: age-related macular degeneration • clinical (human) or epidemiologic studies: outcomes/complications • clinical (human) or epidemiologic studies: risk factor assessment