Visual Acuity Loss Not Significantly Impacted by Care Delay Due to COVID-19 Pandemic

Timothy M. Janetos, MD

Credit: LinkedIn

Clinical outcomes among patients with neovascular age-related macular degeneration (nAMD) did not vary significantly after a delay in care due to the COVID-19 pandemic, according to new findings.¹

Compared to historical rates, rates of visual acuity loss were not significantly different in the pre- versus post-COVID-19 lockdown periods; however, both treatment and anatomic outcome variables in nAMD eyes showed worsening in the post-lockdown period.

“It suggests that in contrast to shorter-term studies, visual acuity was not significantly impacted by the mandated lockdown period although both anti-vascular endothelial growth factor (VEGF) treatments increased, and some anatomic factors worsened after care delay,” wrote the investigative team, led by Timothy M. Janetos, MD, department of ophthalmology, Northwestern University Feinberg School of Medicine.

Beginning in March 2020, when COVID-19 was officially declared a pandemic by the World Health Organization, outpatient services across all fields of medicine, including ophthalmology, were intentionally closed. The impact of this delay in routine care and patient hesitancy to resume care utilization is still beginning to be understood. For those with nAMD, the American Academy of Ophthalmology (AAO) considered intravitreal anti-VEGF injections an emergent procedure, but many patients still delayed care due to a variety of factors.²

Literature has suggested patients who discontinue nAMD treatment for prolonged intervals are in danger of vision loss, but there is less knowledge on the effect of shorter-term care delays. Some studies have reported visual acuity loss linked to these delays, but challenges, including short follow-up time and inadequate comparison groups, limit the ability to draw conclusions.

Janetos and colleagues aimed to model visual acuity with long-term outcomes using a longitudinal data set, to better capture visual acuity outcomes and determine the effect of a delay in care.¹ In addition, they set out to uncover any predictive baseline factors influencing visual acuity outcomes in the study cohort.

Participants with nAMD were selected if they had ≥1 canceled, no-show, or rescheduled retina-related appointment during the mandated lockdown period (May 2020 through May 2020). Data were collected on the cohort from March 2019 through July 2021 to allow for 1 year of historic data to be compared with ≥1-year follow-up data.

Visual acuity was modeled using a linear longitudinal mixed-effects model comparing the pre-lockdown period (March 2019 - March 2020) to the post-lockdown period (March 2020 - July 2021). The interaction between each period and visual slopes were used to determine if they differed significantly and thus, represented a significant change in visual acuity after care delay.

Covariates for the mixed-effects model included baseline anatomic variables, demographic variables, and time intervals. Moreover, secondary outcomes, consisting of time-varying anti-VEGF injections, subretinal and intraretinal fluid status, and macular hemorrhage status, were modeled using a multilevel binary logistic regression model.

A total of 163 eyes among 116 patients were included for analysis. The population experienced an average delay interval of 79.5 days, compared with an average treatment interval of 60.5 days prior to lockdown.

Upon analysis, the initial longitudinal mixed-effects model showed the overall visual acuity decreased at a yearly rate during the study period (0.07154 logMAR/year; 95% CI, 0.02336 - 0.11972; P = .004). However, the interaction between the pre- and post-lockdown period was not significant (P = .703), suggesting visual acuity did not decrease at a different rate following a delay in care.

The single-covariate model indicated male sex (P = .038) and a shorter delay interval (P = .036) significantly affected the visual acuity slope. According to the multivariate longitudinal model, however, male sex did not remain a significant factor, while the delay interval’s effect on the visual acuity slope was significant (P = .044).

Investigators noted neither the treatment status nor treatment interval significantly impacted overall visual acuity or the rate of vision loss in the patients, while no anatomic factor predicted the visual acuity slope. In the multilevel binary logistic regression models, the team found the odds of receiving an anti-VEGF treatment, the presence of subretinal fluid, and macular hemorrhage were greater in the post-lockdown period.

“Intraretinal fluid, one of the most important markers of disease activity, did not change significantly after care delay which may have contributed to preservation of vision,” investigators wrote.

References

1. Janetos TM, Zandi R, Younessi D, Johnson G, Randolph A, Gill M. Clinical outcomes in neovascular age-related macular degeneration: a cohort study of patients with care delay due to the COVID-19 pandemic. Sci Rep. 2023;13(1):14814. Published 2023 Sep 8. doi:10.1038/s41598-023-41497-4
2. Recommendations for Urgent and Nonurgent Patient Care. https://www.aao.org/headline/new-recommendations-urgent-nonur gent-patient-care (American Academy of Ophthalmology, 2020).