Refractive changes, cataracts, nerve palsies, diabetic retinopathy, and glaucoma are some of the common ocular morbidities arising from diabetes, said Dr Neeraj Sanduja, MBBS, MS – Ophthalmology.
“Diabetes mellitus (DM) has been identified as one of the leading systemic risk factors for Dry Eye Syndrome (DES). An increasing prevalence of diabetes-associated DES has been reported in recent years with 15–33 per cent prevalence in those over 65 years of age, which further increases as one grows older, ” the expert added.
A burning sensation, foreign body sensation, stickiness, watering, red eye, photophobia, and blurring of vision are some common symptoms. “It has been seen that gritty sensation is the most prominent symptom followed by the abnormalities of the tear film in patients with diabetes-related DES. Severe cases may give rise to ocular complications such as keratoepitheliopathy and keratitis,” said Dr Sanduja.
Peripheral neuropathy, secondary to high blood glucose levels, insulin insufficiency, inflammation, and autonomic dysfunction, accounts for the development of the dry eye. “Also, tear film dysfunction has been found to be closely associated with DES. Human tear film comprises three layers: lipid (secreted by the meibomian gland), aqueous (secreted by the lacrimal gland), and mucin (secreted by conjunctiva, cornea, lacrimal gland, and other structures). DM-associated DES may be aqueous tear-deficient or evaporative dry eye (meibomian gland dysfunction, eyelid problems, low blink rate),” said Dr Sanduja.
“Also, DM is a risk factor for corneal epithelial abnormalities. Patients with more than 10 years of diabetes have shown to have a strong association with dry eyes. State of control of diabetes is the second factor which is significantly associated with DES. Patients with poor glycemic control (HbA1c =8%) have higher degree of dry eyes. Also, DES in patients with type 2 DM is significantly associated with increasing age,” Dr Sanduja added.
The early diagnosis and treatment of dry eye are essential to avoid complications. The application of artificial tears helps improve symptoms, and temporarily improves blurred vision. The most widely used anti-inflammatory drugs are corticosteroids, nonsteroidal anti-inflammatory drugs, cyclosporin A, tacrolimus, and autologous blood serum eye drops. Topical corticosteroids reduce the signs, symptoms, and the level of inflammation in dry eyes and prevent corneal epithelial damage, Dr Sanduja said.
Drugs like 0.05 per cent cyclosporine and tacrolimus increase tear production, suppress immune response, and reduce damage to cells induced by inflammation, said Dr Sanduja.
Preservative-free artificial tears and short-term anti-inflammatory drugs are recommended to improve the tears and to reduce the local inflammatory reaction, especially in long duration of diabetes and in patients with poor glycemic control.