Abstract
Abstract: :
Purpose: In some long–term diabetics with arthritis there appears to be an innate resistance to the development of diabetic retinopathy, displaying a "protective factor" effect. Use of oral COX2 inhibitors in this group appears to interfere with this protection and result in rapid onset of diabetic retinopathy in some patients. We compared the incidence of "breakthrough" diabetic–like retinal vascular abnormalities observed among insulin–dependent and non–insulin dependent members of this group and compared improvement or resolution of retinopathy with cessation of use of the COX2 inhibitors. Methods: We studied the retinal appearance for retinopathy in 81 patients with co–existing arthritis and long–term diabetes. We prospectively followed and examined all patients for retinal changes, especially in the subset of these patients taking COX2 inhibitors. We compared the incidence of retinopathy seen in the insulin dependent versus non–insulin dependent patients and the effect of cessation of the use of COX2 inhibitors had on the retinal appearance. Results: 81 patients (31M, 50 F) age 31–96 years (aver 65.3) with long–term diabetes (13–61 yrs, aver 27.5) were studied. Among the 81 patients, 16 took COX2 inhibitors for their arthritis pain. Of those taking the medication, sudden onset retinal–bleeding characteristic of severe background or early proliferative retinopathy occurred in 9/10 (90%) of IDDM, but only in 1/6 (16.7%) of NIDDM. All ten of the patients with "breakthrough" retinopathy spontaneously improved ophthalmoscopically after discontinuing the COX2 inhibitors. Conclusions: Loss of the potential retinal "protective factor" effect seen in patients with co–existing diabetes and arthritis is more sensitive (vulnerable) in insulin dependent patients than in non–insulin dependent patients when exposed to COX2 inhibitors. However, this rapid onset of "breakthrough" retinopathy seems spontaneously reversible in both groups with cessation of the use of COX2 inhibitors.
Keywords: diabetic retinopathy • diabetes • immune tolerance/privilege