Abstract
Purpose :
To investigate the association between corneal nerve metrics, ocular surface integrity, and renal function in diabetes, and to compare the ocular surface integrity and corneal nerve status in diabetic patients with and without chronic kidney diseases (CKD).
Methods :
This observational clinical study included 588 patients with type 2 diabetes. All subjects received laboratory assessments for renal function, in vivo confocal microscopy examinations for corneal nerves, epithelial and dendritic cells, and ocular surface assessments. eGFR was calculated and the cohort was categorized into two groups: CKD group (eGFR <60 mL/min/ 1.73 m2; n=87) and non-CKD group (eGFR ≥60 mL/min/1.73 m2; n=452). The patients’ demographics and blood tests were collected. Univariate and multivariate regression analysis were used to determine the relationship between corneal nerve variables and renal functional parameters.
Results :
After adjusting for all cofounders, multivariate regression analysis demonstrated that higher urine albumin was associated with lower corneal nerve fiber density (CNFD; β =-0.004, P=0.019), higher urine albumin and higher urine albumin/creatinine ratio were associated with higher corneal nerve fiber width (CNFW; β =0.000001, P<0.001; β =0.00001, P=0.001, respectively). Compared to non-CKD patients, CKD cohort presented significantly lower CNFD (P=0.001), nerve fiber length (P<0.001), nerve fiber area (P=0.027), and nerve fiber fractal dimension (P=0.001), as well as increased CNFW (P=0.001), decreased epithelial cell count (P=0.026), cell density (P=0.003), and larger epithelial cell size (P=0.001), decreased tear break up time (P<0.001). CKD patients also presented with significantly lower Schirmer’s value (P=0.021), higher increased corneal staining NEI score (P=0.010) and Ocular Surface Disease Index Questionnaire score (P=0.015).
Conclusions :
In diabetes, the impairment of corneal nerve is associated the damage of kidney function. CKD patients demonstrated significant worse corneal nerve metrics and ocular surface health. Diabetic corneal neuropathy can be used as a surrogate marker for diabetic nephropathy.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.