A case – control study of retinal Venous occlusion in respect to Prevalence of common risk factors At kles dr prabhakar kore hospital & Medical research centre, belagavi.

Abstract

Retinal venous occlusion is one of the important retinal vascular diseases that are sight – threatening, it is also one of the most common causes of loss of vision. The possible causes are an athero – sclerotic artery compressing the vein and intra – luminal thrombosis. It is usually seen in elderly patients. Retinal venous occlusions are classified as CRVO, HRVO, and BRVO. Retinal venous occlusion approximately affects about 13.4 million adult world population, 3.5 million affected by CRVO, and 12.9 million involved by BRVO. Multiple studies have shown the incidence of RVO to be about 1.6 % – 3.0 % in the elderly population, BRVO incidence is about 1.8 % and CRVO incidence is 0.2 %. The BRVO prevalence is about 0.5 % to 2 % and CRVO prevalence is 0.1 % to 0.2 %. The occurrence of occlusion is usually unilateral in both the cases of BRVO and CRVO. The assessment of risk factors associated with RVO is important, as it gives the health providers the area on which they can work and improve the management of RVO. Therefore, this assessment was done to know the risk factors associated with the cases when compared with the controls, who were age and sex – matched. The present study aimed to study the prevalence of systemic risk factors, present in cases presenting with CRVO or BRVO or HRVO, and compare them with age and sex – matched controls. The study design of the present study was a One Year Case – Control; prospective, comparative, non – interventional observation study, where 31 cases and 31 controls were compared. In the present study majority of the patients belonged to the age group of 61 – 70, i.e., 19, 61.4 %, further 9 patients i.e., 29 % of the study subjects belonged to the age group of 51 – 60 years and 9.6 % of the patients belonged to the age group of 40 – 50 years. 58 % i.e., 18 patients in each group were males, and 42 %, i.e., 13 patients in xiv each group were females. 42 % i.e., 13 patients’ left eyes were affected and 58 %, i.e., 18 patients’ right eyes were affected in cases. In controls, 48 % i.e., 15 patients’ left eyes were affected, right eyes were affected in 16 patients i.e., 52 % of the patients. In our study, no significance was noted in the laterality of the affected eye. There was no significant age and sex – wise distribution noted. overall, the cases had more co – morbidities, 23 (74 %) of the study participants in cases were hypertensive, followed by 22 (71 %) patients who were obese, followed by 21 (61.2 %) of patients who were diabetics. 6 (19.3 %) of the study subjects of cases were having glaucoma, 16 (51.6 %) of the study subjects in cases were having hyper – lipidaemia, 4 (13 %) of the study subjects were having a history of heart disease. The controls had a lower number of co – morbidities where 11 (35.4 %) of the participants were hypertensive, 12 (38.7 %) had diabetes, 10 (32.2 %) had obesity, only 2 (7%) of the patients in the control group had a history of heart disease. No patient in the control group had glaucoma, 6 (19.3 %) of the patients had hyper – lipidaemia. In the present study, 19 (61.3 %) of the study subjects in cases were smokers and 12 (38.7 %) were non – smokers, whereas in the control group only 8 (25.8 %) study subjects were smokers and 23 (74.2 %) were non – smokers. The association was statistically significant with chi – square value of 7.939 and p – value of 0.002. Ischemic CRVO was seen in 5 (16.5 %) of the cases, non – ischemic CRVO was seen in 4 (13.5 %) of the cases, superior HRVO was seen in only 1 (3 %) of the cases, inferior HRVO was seen in 4 (13.5 %) of the patients. ST BRVO was seen in maximum number with 8 (26.2 %) patients, IT BRVO was seen in 5 (16.5 %) patients and MT BRVO was seen in 4 (10.8 %) of the cases. The mean systolic blood pressure in the cases was 138.48 ± 14.51, whereas the mean systolic blood pressure in the controls was 122.47 ± 10.66, this mean difference was statistically significant with a t xv – value of 4.95 and p – value of < 0.001. The mean diastolic blood pressure in the cases was 89.44 ± 10.54, whereas the mean diastolic blood pressure in the controls was 78.94 ± 11.45, this mean difference was statistically significant with a t – value of 3.77 and p – value of 0.003. The mean HbA1c in the cases was 7.95 ± 1.22, whereas the mean HbA1c value in the controls was 6.14 ± 0.69, this mean difference was statistically significant with a t – value of 7.74 and p – value of 0.001. The mean serum creatinine levels in the cases were 1.02 ± 0.24, whereas the mean creatinine levels in the controls were 6.14 ± 0.69, this difference in the mean was statistically not significant with a t – value of 1.38 and p – value of 0.170. The mean blood urea in the cases was 18.45 ± 3.45, whereas the mean blood urea in the controls was 16.74 ± 4.58, this mean difference was statistically not significant with a t – value of 1.66 and p – value of 0. 102. The mean BMI in the cases was 28.45 ± 4.66, whereas the mean BMI in the controls was 22.48 ± 3.14, this mean difference was statistically significant with a t – value of 5.91 and p – value of 0.0001.