Purpose:
The purpose of this study was to determine if giving lutein (L) or zeaxanthin (Z) supplements to diabetic (DM) patients with no evidence of maculopathy would increase their macular pigment levels.
Methods:
Patients with DM without maculopathy were enrolled in the clinical trial. Each was randomly assigned to one of four supplementation formulations containing different amounts of L or Z. Patients were examined at baseline, 1 month, 3 months, 6 months, and 1 year. At each visit patients were imaged with two objective techniques for measuring MP. MPOD was measured with a modified scanning laser ophthalmoscope (HRA Heidelberg Retinal Angiograph, Heidelberg, Germany). LOD and ZOD were measured with the Macular Pigment Reflectometer (MPR,Maastricht, Netherlands). Paired t-tests were used to compare mean optical densities. We are reporting the preliminary 6 month data.
Results:
Initially 10 patients were enrolled. However, four patients were lost to follow-up and one had inadequate images for analysis. 9 eyes of 5 patients were included. 60% were male. Mean age was 57.8±8.8 yrs. 60% were Hispanic, 20% Caucasian, and 20% African American. All patients had Type II DM. Mean duration of DM was 21±11.4 yrs and mean HbA1C was 6.55±0.75 mg/dL. Changes in mean MPOD, ZOD, and LOD are shown in Table 1. Each parameter showed significant increases from baseline after 1-3 months of supplementation. Increases in mean LOD and ZOD measured by MPR were higher relative to the increases in mean MPOD measured with HRA.
Conclusions:
A previous study demonstrated that patients with Type II DM had lower levels of macular pigment, inversely proportional to their HbA1C levels. It was unclear whether this reflected absorption difficulties or increased breakdown. These preliminary results suggest that diabetic patients are capable of absorbing supplements, allowing increased macular levels of L and Z. This also suggests that the increased oxidative stress associated with DM results in more rapid breakdown of antioxidant pigments, leaving the macula more vulnerable to the onset of macular disease. Additional patient enrollment is needed to confirm these results and further studies are necessary to correlate MP supplementation and the oxidative stress of DM.
Clinical Trial:
http://www.clinicaltrials.gov NYEE0936
Keywords: diabetes • macular pigment • imaging/image analysis: clinical