Lapses in Care Observed in Patients Assigned To Ranibizumab for PDR Treatment

Due to the importance of frequent monitoring in patients treated with anti-vascular endothelial growth factor agents for proliferative diabetic retinopathy (PDR), the ability to identify characteristics of patients likely to comply with the intensive follow-up schedule is important for clinicians.

Thus, led by Adam R. Glassman, MS, Jaeb Center for Health Research, a team of investigators looked to describe both the frequency and pattern of lapses in follow-up of participants assigned to ranibizumab for PDR treatment.

Results from the multi-center, randomized clinical trial showed the team that throughout the 5 year follow-up period, approximately half of participants assigned to ranibizumab for PDR had long lapses in care, despite efforts to facilitate completion of examinations.

What were the methods?

The study consisted of 305 adults with PDR from 55 clinical sites in the US enrolled in Protocol S between February - December 2012. From this number, both eyes were enrolled for 89 participants and each eye was then randomly assigned to 1 group.

Eyes were randomized to ranibizumab injections of 0.5 mg (n = 191) or PRP (n = 203). The final 2-year visit was completed in January 2015, while data were analyzed from April 2019 - July 2021.

For participants assigned to ranibizumab, eyes received injections every 4 weeks through week 24, while injections were deferred at weeks 6 if neovascularization (NV) had been resolved. Then, at 24 weeks, the injections were continued every 4 weeks if NV had improved or worsened, but could be deferred if NV was stable after 2 consecutive injections.

Under the post hoc analysis, a lapse in care was defined as more than 2 weeks past the target date for a visit scheduled either 4 or 8 weeks after a completed visit, or more than 4 weeks past the target data for a visit scheduled 16 or more weeks after a completed visit.

Furthermore, a short lapse occurred when a participant returned within 8 weeks from the target date for the next visit, while a long lapse in care occurred if the participant did not return by 8 weeks past the target date.

What were the findings?

The study included 170 participants with a median age of 51 years and 44.7% (n = 76) were female. Self-reported race and ethnicity showed 51.8% of patients were non-Hispanic white, followed by 24.7% were Hispanic and 20.6% were Black.

Over the 5-year follow-up period, 94 of 170 participants (55.3%) had 1 or more long lapses in care, while 50 participants (29.4%) had short lapses only. Then, 69 of 94 participants (73.4%) returned for examination after the long lapse and 25 (36.2%) dropped out later.

At 52 weeks, data show 79 participants (46.5%) had any lapses in care, 30 (17.6%) had a long lapse, and 15 (8.8%) had dropped out. Additionally, the median time to first lapse in case was 62 weeks and to the first long lapse in care was 210 weeks.

By 5 years, 50 participants (29.4%) dropped out of follow-up and 120 participants completed the examination. The median change from baseline VA was observed to be +4 letters (-1 to +9) in the group having no lapse in case, +5 letters (+1 to +10) for the group with short lapses, and -2 letters (-6 to +11) in group with ≥1 long lapses, P = .05.

What were the takeaways?   

To summarize, investigators noted that 90% of participants in the study returned for at least 1 visit after their first lapse in care, which led them to believe factors including worse VA at baseline did not predict who would have a long lapse in care.

“This finding suggests that clinicians may have opportunities to counsel returning patients about the importance of timely follow-up to optimize their outcomes,” investigators wrote.

The study, “Lapses in Care Among Patients Assigned to Ranibizumab for Proliferative Diabetic Retinopathy: A Post Hoc Analysis of a Randomized Clinical Trial,” was published in JAMA Ophthalmology.