Correlations between metabolic indices and visual parameters in diabetic patients

Abstract

Aim: To explore associations between metabolic, haematological, renal and visual parameters in diabetics.Methods: 131 patients were recruited from the diabetic clinics at Airedale General Hospital. Those with proliferative DR or cataract were excluded from the study. Blood pressure was measured at rest and the measurements of plasma glucose, glycosylated haemoglobin and microalbuminuria were taken. Fundus photography was used to classify the extent of DR and ophthalmoscopic examination of the macula was performed. Visual function assessments included the measurement of refractive error, logMAR visual acuity, contrast sensitivity using gratings at three spatial frequencies and the Pelli‐Robson letter chart and hue discrimination using the Arden Colour Contrast Sensitivity apparatus. An assessment of the relationship between the metabolic indices and visual function was performed using the Kendall Tau Correlation Test.Results and conclusions: The only meaningful correlation between a clinical optometric test and a metabolic parameter was between refractive error and glycosylated haemoglobin levels (P < 0.05). As HBA1C levels increased refractive error tended towards myopia. The normal hypermetropic shift with age was observed. Rx changes may be indicative of poor long‐term metabolic control. There were little/no associations between any other renal, metabolic, haematological or visual parameters contrary to other studies. This may be due to the strict exclusion criteria.