Tear secretion and tear film function in insulin dependent diabetics.

BACKGROUND Diabetic patients often complain of dry eye symptoms, such as burning and/or foreign body sensation. The aim of the present study was to investigate whether diabetes mellitus is correlated with tear film dysfunction and/or tear hyposecretion. METHODS In 86 consecutive insulin dependent diabetics with retinopathy and 84 non-diabetic controls (age and sex matched) we performed fluorophotometry of tear secretion, the Schirmer test, and impression cytology of the conjunctival epithelium and determined the tear film break up time. RESULTS When compared with the healthy control group diabetics showed decreased Schirmer test readings (-37%, p <0.001) and significantly more frequent and pronounced signs of conjunctival metaplasia. None of the other values differed between groups. CONCLUSION In insulin dependent diabetics, reflex tearing was demonstrated to be significantly decreased. In contrast, unstimulated basal tear flow and tear film break up time were found to be normal. However, a majority of insulin dependent diabetics shows distinct signs of conjunctival surface disease.