Clinical Profile, Risk Factors, and Visual Outcomes Following Intravitreal Ranibizumab Therapy in Patients with Diabetic Retinopathy

Abstract

Background: Diabetic retinopathy causes substantial avoidable visual impairment, while cost and irregular follow-up may limit intravitreal therapy in low-resource settings.

 Objective: To describe the clinical profile, risk factors, and six-month visual outcomes following intravitreal ranibizumab among patients with diabetic retinopathy in Pakistan.

Methods: This prospective multicenter cohort included adults with centre-involving diabetic macular edema treated at three tertiary hospitals from January to December 2025. Participants received ranibizumab 0.5 mg as three monthly loading doses followed by pro re nata treatment. Best-corrected visual acuity, central subfield thickness, systemic risks, adherence, and adverse events were recorded. The primary outcome was a gain of at least 10 Early Treatment Diabetic Retinopathy Study letters at six months.

Results: Among 216 enrolled participants, 198 completed follow-up. Mean age was 57.6±8.9 years, 55.6% were men, and mean glycated hemoglobin was 8.6±1.4%. Visual acuity improved from 0.68±0.26 to 0.42±0.25 logMAR, while central subfield thickness decreased from 442±91 to 315±72 µm (both p<0.001). Eighty-six participants (43.4%) gained at least 10 letters. Adherence independently increased improvement, whereas glycated hemoglobin ≥9%, symptoms exceeding six months, and outer-retinal disruption reduced it. No endophthalmitis occurred.

Conclusion: Ranibizumab produced meaningful anatomical and visual improvement under routine tertiary-care conditions. Timely presentation, metabolic control, and scheduled injections were important response determinants.