[Frequency and causes of blindness and poor vision in Congolese diabetic patients]

To determine the frequency and the causes of blindness and visual impairment among patients with diabetes mellitus from DR Congo.

In this observational study of series, records of all consecutive patients with diabetes mellitus seen between April 1, 2004 and April 30, 2006 in the Division of Ophthalmology, University of Kinshasa, were retrospectively assessed and included. Eye examination including measurement of visual acuity, slit lamp examination, funduscopy and tonometry was performed in all patients. Fluorescein angiography was performed when needed. The World Health Organization criteria and the recommendations for the revision were used for blindness and visual impairment definitions.

During the study period, 299 patients with diabetes mellitus were examined, giving a frequency of 2% (299 out of 13401 patients). There were 194 males (65%) and 105 females (35%). Ages ranged from 21 to 88 years (mean age+/-SD, 58 years+/-10). The mean duration of diabetes mellitus was 7+/-8 years and its median duration was 4 years. Frequency of blindness and that of visual impairment were 12% and 24%, respectively. Causes of blindness were diabetic retinopathy (47%), cataract (33%), glaucoma (17%) and optic nerve atrophy (2.8%).

This study shows an unexpected higher frequency of blindness in diabetic patients when compared with previous African studies and those of other parts of the world. Blindness seemed to appear early in Congolese diabetic patients than in Caucasian diabetic patients. Diabetic Retinopathy remains the common cause of blindness among Congolese diabetic patients. Programmes must be drafted for prevention, early detection and treatment of blindness among diabetics.