Angiotensin-receptor blockers may help diabetic retinopathy

The Diabetic Retinopathy Candesartan Trial (DIRECT) aimed to examine the effects of candesartan on the incidence and progression of diabetic retinopathy in patients with type-1 and type-2 diabetes.

The trial consisted of three studies: primary and secondary prevention studies in normotensive patients with type-1 diabetes, and secondary prevention in either normotensive or treated hypertensive patients with type-2 diabetes.

A total of 4,500 patients were randomised to receive either 32mg candesartan or placebo for a period of three years at over 300 centres worldwide.

The trial failed to reach its primary endpoints but showed an 18 per cent reduction in incidence of diabetic retinopathy in type-1 diabetic patients (p=0.0508), and a 13 per cent reduction in risk of progression of retinopathy in patients with type-2 diabetes (p=0.2). Regression of retinopathy was also increased by 34 per cent compared with placebo in patients with type-2 diabetes taking candesartan (p=0.009).

The authors concluded that treatment with candesartan may confer benefit for retinopathy in patients with diabetes.

Dr Nish Chaturvedi, one of the principal investigators of the trial, said that the results suggest that: ‘GPs should be thinking about prescribing candesartan above other agents in patients with type-2 diabetes and retinopathy who develop hypertension.'

Commenting on the results, Dr George Kassianos, a Berkshire GP, said ‘The results of this trial are not negative, they are positive because they are the first in this field and because they reinforce the beneficial effects of these drugs. We need to ensure that patients with type-1 and type-2 diabetes are on drugs like candesartan in order to prevent macro-and microvascular complications.'

sharon.pickett@haymarket.com

Comment below and tell us what you think