Progression to Pars Plana Vitrectomy in Patients With Proliferative Diabetic Retinopathy

The Diabetic Retinopathy Clinical Research Network Protocol S suggested that vitrectomy for vitreous hemorrhage (VH) or tractional retinal detachment (TRD) was more common among eyes assigned initially to panretinal photocoagulation (PRP) vs anti-vascular endothelial growth factor (anti-VEGF) for proliferative diabetic retinopathy (PDR). These clinical implications warrant further evaluation in the clinical practice setting.

To explore outcomes of PDR treated with PRP monotherapy compared with matched patients treated with anti-VEGF monotherapy.

Retrospective cohort study using an aggregated electronic health records research network. Patients with PDR who received PRP or anti-VEGF monotherapy between January and September 2023 were included before propensity score matching. Patients were excluded with 6 or fewer months' follow-up after monotherapy or with a combination of PRP and anti-VEGF. Data were analyzed in September 2023.

Patients with new PDR diagnoses stratified by monotherapy with PRP or anti-VEGF agents using Current Procedural Terminology code.

Incidence of pars plana vitrectomy (PPV), VH, or TRD.

Among 6020 patients (PRP cohort: mean [SD] age, 64.8 [13.4]; 6424 [50.88%] female; 3562 [28.21%] Black, 6180 [48.95%] White, and 2716 [21.51%] unknown race; anti-VEGF cohort: mean [SD] age, 66.1 [13.2]; 5399 [50.52%] male; 2859 [26.75%] Black, 5377 [50.31%] White, and 2382 [22.29%] unknown race) who received treatment, PRP monotherapy was associated with higher rates of PPV when compared with patients treated with anti-VEGF monotherapy at 5 years (RR, 1.18; 95% CI, 1.05-1.36; RD, 1.37%; 95% CI, 0.39%-2.37%; P < .001), with similar associations at 1 and 3 years. PRP monotherapy was associated with higher rates of VH at 5 years (relative risk [RR], 1.72; 95% CI, 1.52-1.95; risk difference [RD], 7.05; 95% CI, 5.41%-8.69%; P < .001) and higher rates of TRD at 5 years (RR, 2.76; 95% CI, 2.26-3.37; RD, 4.25%; 95% CI, 3.45%-5.05%; P < .001), with similar magnitudes of associations at 6 months, 1 year, and 3 years, when compared with patients treated with anti-VEGF monotherapy.

These findings support the hypothesis that patients with PDR treated with PRP monotherapy are more likely to develop VH, TRD, and undergo PPV when compared with matched patients treated with anti-VEGF monotherapy. However, given the wide range in relative risk, confounding factors may account for some of the association between PRP vs anti-VEGF monotherapy and outcomes evaluated.