Use of Imaging Modalities in Real Life: Impact on Visual Acuity Outcomes of Ranibizumab Treatment for Neovascular Age-Related Macular Degeneration in Germany

A model to quantify the influence of treatment patterns and optimize outcomes in nAMD

Neovascular age-related macular degeneration (nAMD) is a progressive retinal disease that often leads to severe and permanent vision loss. Early initiation of anti-vascular endothelial growth factor (anti-VEGF) therapy has been shown to preserve vision in nAMD patients. Concurrently, treatment outcomes in real-world are inferior to those reported in clinical trials. The most likely reasons observed are fewer treatment-intensity in routine clinical practice than in clinical trials. The other possibility could be the delay in starting treatment and the re-treatment interval. Although a negative impact of aforementioned parameters seems obvious, quantitative impact measures remain elusive in a real-world setting due to a lack of an ‘optimal treatment’ control group. To overcome this shortcoming, we developed, validated, and applied a model to assess and quantify the impact of anti-VEGF administration variables on visual acuity development in a prospective nAMD patient cohort. The model was further applied to probe the impact of the COVID-19 pandemic on visual progressions in nAMD patients. The presented model paves the way to systematically explore and evaluate realistic interventions in the current treatment paradigm, that can be adopted in routine clinical care.

Importance of Treatment Duration: Unmasking Barriers and Discovering the Reasons for Undertreatment of Anti-VEGF Agents in Neovascular Age-Related Macular Degeneration

Purpose

Since non-adherence (NA) to intravitreal therapy with VEGF drugs is one of the most important modifiable factors compromising treatment outcome of nAMD, the purpose of this study was to investigate the contributing factors and barriers during long-term nAMD treatment.

Methods

Barriers and potential reasons for NA were prospectively measured using the Adherence Barriers Questionnaire Intravitreal Therapy (ABQ-IVT). A random sample of patients receiving intravitreal therapy was drawn based on data for different treatment periods. Three age-sex matched groups included the treatment periods of ≤30 months (group 1), between >30 months and ≤60 months (group 2), and >60 months (group 3). The occurrence of gaps between treatments and/or OCT visits was evaluated.

Results

NA with gaps of >56 days after the scheduled appointment was detected in 39%, 89%, and 100% of patients in group 1, 2, and 3, respectively (groups 1 and 2 vs group 3, p < 0.001). Two or more of such gaps were observed in 6%, 72%, and 94% of patients in group 1, 2, and 3, respectively. The overall ABQ-IVT score showed corresponding differences between the groups: 25.89 ± 7.68 (group 1, 95% CI 22.07–29.71), 34.72 ± 10.32 (group 2, 95% CI: 29.59–38.86), and 33.28 ± 9.04 (group 3, 95% CI 28.78–37.77). Accordingly, the score was inversely correlated with the number of regular follow-up visits in groups 2 and 3 (Pearson correlation coefficient r = −0.65 (p = 0.003) and r = −0.5 (p = 0.034), respectively). Within the groups of longer treatment duration, univariate logistic regression analysis showed higher odds of time commitment and challenge accompanying person to be relevant barriers.

Conclusion

NA is an arising problem with increasing duration of intravitreal therapy. Treatment barriers, detected by the ABQ-IVT, might change or increase during the course of the treatment.

Questionnaire for the assessment of adherence barriers of intravitreal therapy: the ABQ-IVT

Objective

To develop and validate a questionnaire for the investigation of non-adherence (NA) barriers in patients receiving intravitreal injection (IVT).

Design

Questionnaire development and cross-sectional patient survey combined with a retrospective medical chart review.

Participants

German patients with neovascular age-related macular degeneration (nAMD) or diabetic macular edema (DME) receiving anti-vascular endothelial growth factor (anti-VEGF) treatment via IVT.

Methods

The previously validated (indications: atrial fibrillation, human immunodeficiency virus, chronic inflammatory lung disease) Adherence Barriers Questionnaire (ABQ) was revised according to specifications of IVT, within the framework of an expert panel. The ABQ-IVT, which initially consisted of 24 items formulated as statements (4-point-Likert-scale ranging from “strongly agree” to “strongly disagree”), was applied in a cross-sectional survey. Evaluation of the questionnaire included an assessment of internal consistency and factor analysis. The occurrence of potential barriers in the patient sample was evaluated using descriptive statistics. To identify patient subpopulations, hierarchical cluster analysis was performed using ABQ-IVT answers as predictors. Due to difficulties in capturing NA as an external criterion, the evaluation of the questionnaire was limited to its internal validity and reliability.

Main outcome measures

Patients’ answers to the ABQ-IVT questionnaire and interviews.

Results

Of 253 patients, 234 (92%) were able to complete the ABQ-IVT questionnaire. Within the reliability analysis, the ABQ-IVT was reduced to 17 items. The condensed questionnaire demonstrated good internal consistency (Cronbach’s alpha = 0.78), and factor analysis showed no evidence for subscales of the questionnaire. Nearly half of the patients (49%) reported being affected by at least three different barriers. On average, a patient was affected by 3.1 barriers. The most frequently reported barriers were “Challenge due to time commitment of physician visits” (45% of the patients), “Depression” (29%) and “Travel and opportunity costs” (27%). Cluster analysis identified six patient subpopulations, each affected by different sets of barriers and differed regarding their patient characteristics.

Conclusions

The ABQ-IVT is a practical and reliable instrument for identifying patient-specific barriers to IVT treatment adherence. In practice, the questionnaire may be useful in assessing whether individual patients are at higher risk of NA due to specific adherence barriers. Aside from better awareness, this allows earlier interventions, though these still need to be validated. Patient subpopulations face different barriers and may, therefore, need distinct preventative care.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40942-021-00311-x.