Abstract
Background: Diabetic Retinopathy (DR) accounts for 5% of the 39 million causes of blindness occurring worldwide
and is estimated to contribute 3% of blindness in Kenya. Dyslipidemia, poor control of sugar, hypertension and
obesity increase the risk of DR in patients with diabetes. This study addresses the gap in information on the
magnitude of DR and its associated factors in patients with type 2 diabetes at Moi Teaching and Referral Hospital
(MTRH).
Objectives: To determine the prevalence and severity of DR and its associated factors in patients with type 2
diabetes mellitus.
Methods: This cross sectional study was conducted amongst patients with type 2 diabetes mellitus in MTRH.
Randomly selected participants underwent anthropometric, laboratory and visual acuity testing. Direct
ophthalmoscopy was used to assess DR and macula edema. Grading of DR was done using international clinical
diabetic retinopathy severity scale. A univariate and multivariate logistic regression model was used to assess
associations of the variables with DR.
Results: Of the 329 participants enrolled, 187 (57%) were female with a mean age of 56.8 (10.99) years. One
hundred and three (31%) had diabetic retinopathy and 39 (12%) had diabetic macula edema. Mild to moderate
non proliferative diabetic retinopathy was the most prevalent grade at 79 (25%). One hundred and eighty
four (56%) of participants had hypertension (133/80; IQR 120/70-150/89) mmHg and 158 (48%) had glycated
haemoglobin between 7-10%. The median for the other assessed factors were as follows: duration of diabetes
5 (9) years, total cholesterol 4.6 (1.3) mmol/l and low density lipoprotein 3.0 (1.5) mmol/l. Increase in duration of
diabetes by 5 years {OR 2.02(95% CI 1.11-3.69); p 0.02}, glycated haemoglobin > 6.5% {OR 2.13(95% CI 1.02-4.42);
p 0.04}, systolic hypertension >160 mmHg {OR 1.02(95% CI 1.01-1.03); p 0.01} were associated with increased
risk of diabetic retinopathy while male gender and body mass index did not. Only 15% of the participants in this
study reported having had previous eye check-up.
Conclusion: A third of patients with type 2 diabetes on follow up at MTRH have DR. Systolic hypertension,
increased duration of diabetes and high glycated haemoglobin were positively associated with increased risk of
developing DR
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