Diabetic retinopathy: intravitreal vascular endothelial growth factor inhibitors for diabetic macular oedema

Diabetic retinopathy is the most common microvascular complication of diabetes. It is also the most common cause of blindness in working-age adults in industrialised nations. Older people and those with worse diabetes control, hypertension, and hyperlipidaemia are most at risk. Diabetic macular oedema, which can occur at any stage of diabetic retinopathy, is related to increased vascular permeability and breakdown of the blood retinal barrier, in part related to increased vascular endothelial growth factor (VEGF) levels. About 1% to 3% of people with diabetes suffer vision loss because of diabetic macular oedema.

We conducted a systematic overview, aiming to answer the following clinical questions: What are the effects of intravitreal VEGF inhibitors versus each other for diabetic macular oedema? What are the effects of intravitreal VEGF inhibitors plus laser therapy versus intravitreal VEGF inhibitors alone for diabetic macular oedema? We searched: Medline, Embase, The Cochrane Library, and other important databases up to September 2014 (Clinical Evidence overviews are updated periodically; please check our website for the most up-to-date version of this overview).

At this update, searching of electronic databases retrieved 240 studies. After deduplication and removal of conference abstracts, 149 records were screened for inclusion in the overview. Appraisal of titles and abstracts led to the exclusion of 90 studies and the further review of 59 full publications. Of the 59 full articles evaluated, eight systematic reviews and four RCTs were added at this update. We performed a GRADE evaluation for four PICO combinations.

In this systematic overview, we categorised the efficacy for six comparisons based on information about the effectiveness and safety of intravitreal VEGF inhibitors aflibercept, bevacizumab, and ranibizumab, and each of these intravitreal VEGF inhibitors plus laser therapy.