Blood pressure drug could stop diabetes patients developing retinopathy
October 20th, 2008
Candesartan is a type of drug used to treat hypertension; it is an angiotensin II receptor antagonist.
Three recent studies have shown that candesartan may stop some people with type 1 diabetes from developing retinopathy, a condition that can lead to blindness. The Diabetic Retinopathy Candesartan Trials (DIRECT) presented data from the randomisation of 5231 patients with Type 1 or Type 2 diabetes treated, over 4 years, with either 32 mg candesartan or placebo. Candesartan only was significantly beneficial in preventing the new development of retinopathy in Type 1 patients after a further post hoc analysis which compared extent of retinopathy. There was no significant effect on the progression of retinopathy in Type 1 patients.
In Type 2 diabetes, the more common variety, done in 1905 people, did not succeed in reducing the progression of retinopathy significantly, but regression of early retinopathy was improved by candesartan. The investigators concluded “Treatment with candesartan in people with type 2 diabetes with mild to moderate retinopathy might induce improvement of retinopathy”.
DIRECT-Protect 2 is the first study showing improvement in retinopathy by a drug in relatively early eye disease, before irreversible damage has occurred. An ACE inhibitor, lisinopril, was shown to reduce the progression of retinopathy in type 1 patients who were already hypertensive whereas the current results were in patients who had a normal blood pressure. Candesartan is commonly used as a treatment for a high blood pressure.
