Abstract
Purpose::
: It has been reported that use of thiazolidinediones ("glitazones") as oral hypoglycemic agents is associated with an increase in diabetic macular edema. We wished to determine, in our own series of patients, whether glitazone therapy has an effect on mean central macular point thickness (CMT) as measured by optical coherence tomography (OCT) in patients with clinically significant diabetic macular edema (CSDME) before and after focal argon laser treatment.
Methods::
The medical charts and computerized OCT records of 142 consecutive patients with CSDME were studied retrospectively. Patients were divided into subgroups based on medication regimen and treatment of CSDME. Mean CMT as measured by OCT mapping software was calculated in all subgroups.
Results::
Fifty-nine patients with OCT records before laser treatment were studied at baseline; 12 patients were on glitazone therapy and 47 were not. One hundred twenty-four patients were studied after laser treatment; 30 patients were on glitazone therapy and 94 were not. Sixty-five of these patients were controlled on an oral medication regimen; 45 were not on glitazones and 20 were on glitazones + other oral medications. Mean CMT did not differ significantly between patients on glitazone therapy and those not on glitazone therapy at baseline (325 + 158 µm vs. 301 + 137 µm) or after treatment (257 + 118 vs. 294 + 139 µm). In patients controlled with an oral medication regimen, mean CMT did not differ significantly in patients on oral medications not including glitazones (299 + 146 µm) compared to patients on glitazones + other oral medications (254 + 130 µm) after treatment.
Conclusions::
In contrast to the recent study by Ryan EH, et al (Retina 2006;26:562-70), which indicated that glitazone therapy may be a cause of macular edema in patients with peripheral fluid retention, we found no significant difference in mean CMT in patients on glitazone therapy when compared to patients on insulin and/or other oral medication regimens before or after argon laser treatment of CSDME.
Keywords: diabetic retinopathy • macula/fovea • edema