Year: 2005
Abstract Number: 871-P
Authors: ABID IQBAL, PANOS KALLINIKOS, NATHAN EFRON, ANDREW J. M. BOULTON, RAYAZ A. MALIK
Institutions: Manchester, United Kingdom
Results: Corneal confocal microscopy (CCFM) is a rapid, non-invasive technique which quantifies corneal nerve damage and has been shown to act as a reliable surrogate measure of somatic neuropathy in diabetic patients. To further validate this technique corneal nerve morphology (nerve fibre density (NFD) (no.mm2), branch density (NFBD) (no.mm2), length (NFL) (μm) and tortuosity (NFT)), was compared in 25 diabetic patients with mild to moderate neuropathy evaluated using the Neuropathy Impairment Score (NIS) and Vibration perception threshold (VPT) and eighteen control subjects at baseline and repeated in the diabetic patients 24 + 1.6 months later. NFD: 18.64±2.09 v 44.48±3.34, p=0.001, NBD: 7.23±1.52 v 78.90±7.16, p<0.0001, NFL: 8.28±0.54 v 13.47±0.80, p<0.0001 were significantly reduced in diabetic patients with no difference in NFT: 20.38±1.6643 v 20.35±1.65, p=0.991. In the diabetic patients between the baseline and follow up scan, corneal nerve morphology improved significantly (NFD (23.53±2.03,P=0.03), NBD (11.13±1.31, P=0.06), NFT (23.22±1.53,P=0.02) with no change in NFL (8.41±0.54, P=0.67). During this period HbA1c (8.1±0.31 to 7.5±0.23, p=0.08), total cholesterol (4.86±0.18 to 4.21±0.19 p=0.01), systolic BP (145.8±4.9 to 135.9±3.7, p =0.09) and diastolic BP (77.8±2.7 to 70.8±2.5, p = 0.03) improved with no significant change in triglycerides (1.75±0.21 to 1.49±0.22 p=0.17) or HDL (1.36±0.07 to 1.34±0.09, p=0.64). The improvement in NFD correlated significantly with the improvement in HbA1c (r=-0.52, p=0.008) but not with total cholesterol (r=-0.32, p=0.12), systolic (r=-0.20, p=0.34) or diastolic (r=-0.02, p=0.91) BP. CCFM appears to be a reliable surrogate marker for the diagnosis of human diabetic neuropathy. Furthermore it provides a future means of assessing therapeutic efficacy in clinical interventon trials, as an improvement in corneal nerve morphology was related to improved glycaemic control.
Category: Complications - Neuropathy