Journal of Ophthalmology & Clinical Research Category: Clinical Type: Research Article
Risk Factors of Retinopathy Among Diabetic’s Patients in Benin in 2014
- Codjo Rodrigue Abel Assavedo1*, Leopold Codjo2, Adébayo Alassani3, Thierry Adoukonou4, Ajoua Pulchérie Codjo5, Salimatou Monteiro6, Ângelo Cossi Attissounon7, Abdoulaye Imorou3, Sidonie Hounnou Tchabi8, Dismand Houinato9, Claudia Doutetien Gbaguidi8
- 1 Unit Of Teaching And Research In Ophthalmology, Faculty Of Medicine, University Of Parakou, Parakou, Benin
- 2 Unit Of Teaching And Research In Cardiology, Department Of Medicine And Medical Specialties, University Of Parakou, Parakou, Benin
- 3 Diabetology Unit, Department Of Medicine And Medical Specialties, University Of Parakou, Parakou, Benin
- 4 Unit Of Teaching And Research In Neurology, Department Of Medicine And Medical Specialties, University Of Parakou, Parakou, Benin
- 5 National School Of Higher Technicians In Public Health And Epidemiological, University Of Parakou, Parakou, Benin
- 6 Unit Of Teaching And Research In Ophthalmology, Faculty Of Medicine, University Of Parakou, BP : 123 - FM/UP- Parakou, Benin
- 7 Unit Of Teaching And Research In Infectious Diseases, Department Of Medicine And Medical Specialties, University Of Parakou, Parakou, Benin
- 8 University Ophthalmology Clinic, Faculty Of Health Sciences, University Of Abomey-Calavi, CNHU-HKM De Cotonou, Cotonou, Benin
- 9 Department Of Opthalmology, University Clinic Of Neurology, CNHU-HKM De Cotonou, Cotonou, Benin
*Corresponding Author:Codjo Rodrigue Abel Assavedo
Unit Of Teaching And Research In Ophthalmology, Faculty Of Medicine, University Of Parakou, Parakou, Benin
Received Date: Jul 13, 2016 Accepted Date: Oct 25, 2016 Published Date: Nov 08, 2016
The Diabetic Retinopathy (DR) is one of the most frequent and most crippling complications of the mellitus diabetes. Its frequency increases with the age and the duration of the evolution of the diabetes.
It was to analyze the risk factors of retinopathy among diabetic patients followed at the Unit of Diabetes of Departmental Universitary Hospital of Borgou and Alibori for the duration of the study.
It was cross-sectional study including 189 diabetic patients followed in the Unit of Diabetes of DUHCB over a period going from May to August, 2014. These patients had benefited of a complete ophthalmological examination. The retina lesions were appreciated using Slosse and Alaerts Classification. The data analyzed were performed with the Epi-data and Epi-info software version 3.5.3.
The prevalence of diabetic retinopathy among the studied population was 17.5% (33/189). The mean age was 55.2 ± 12.3 years. The sex ratio was 0.75 (M/F). The associated risks factors to the diabetic retinopathy were: age superior to 50 years (p=0.020), the duration of the diabetes (p=0.000), blood sugar over or equal to 1.26g/l (p=0.036) and the presence of nephropathy (p=0.016).
The frequency of diabetic retinopathy is low among the diabetics patients followed at the DUHCB since the starting of work in the Unit of Diabetes. The associated risks factors in our study are largely the same to those of anterior studies realized in various regions of the world. Its screening must be systematic among the diabetics.
Our study aims to analyze the risk factors associated with retinopathy in diabetic patients followed in the management Unit of Diabetes at the Departmental Universitary Hospital of Borgou and Alibori Borgou in 2014.
PATIENTS AND METHODS
In this study, all patients are diabetic and monitored in the Unit of Diabetes care for the Departmental Universitary Hospital of Borgou and Alibori, who gave their informed consent and for whom a complete ophthalmic examination was performed. Sampling was done in a non-probability method and comprehensive techniques.
We conducted a systematic recruitment of all patients who gave informed consent.
The dependent variable was the presence of retinal lesions.
We used the classification of Alaert and Slosse  for retinal damage:
• Stage II: Micro aneurysms + Stage I
• Stage III: Hemorrhages, exudates and micro aneurysms + Stage II
• Stage IV: Dilation of large vessels and bleeding Stage + III
• Stage V: Neovessels + Stage IV (stage retinopathy proliferative diabetic)
• Stage VI: Neovascular glaucoma + Stage V (stage complicated diabetic retinopathy)
The retinal angiography was not performed; our unit does not have it.
Independent variables were age, sex, cardiovascular risk factors (body mass index, hypertension, smoking, physical inactivity), duration of diabetes, balance of diabetes, complications (neuropathy, nephropathy, diabetic foot), therapeutic modalities and ophthalmologic data.
Marital status: Married (e) (lives in couple); single, divorced (e), widow (er) (constituted the group of those who were not living with a partner).
Cardiovascular risk factors: Body Mass Index (BMI), calculated using the formula: weight (kg)/height square (m²). It was expressed in Kg/m².
We had considered
• Skinny, any subject with a BMI<18.5 kg/m²
• Normal weight, a BMI between 18.5 and 24.9 kg/m²
• Weight overload, any subject with a BMI between 25 and 29.9 kg/m²
• Obese, any subject with a BMI≥30 kg/m²
• Tobacco (smoked, chewed or popular) whether we specified the number of package/year
Sedentarity: No if the patient practice at least 30 minutes of moderate physical activity three times a week, or so.
Features and other degenerative complications of diabetes
• The neuropathy, if the patient had any of the following symptoms (burning, coldness, tingling, numbness)
• The nephropathy was revealed by a disturbed renal function tests (serum creatinine>14mg/l)/or the presence of albumin in the urine test strip or proteinuria after 24h
• Diabetic foot, if the presence of trophic disorder or amputation of the pelvic members and not otherwise.
• Hyper blood pressure, if the patient had a history of hypertension or antihypertensive treatment and not otherwise
The intraocular pressure: It was valued by Goldman applanation tonometer after contact anesthesia by oxybupacaine. It was classified as follows: Hypotonia (IOP<10mmHg), Normal (10≤IOP<21mmHg) and Hypertension (IOP≥21mmHg).
• All these data were collected using an ad hoc form, through a questionnaire, physical examination and ophthalmoscopy performed for each patient
• The selected patients were reviewed by the ophthalmologist for a complete eye examination. Ophthalmoscopy was performed using a 90 diopters Volk lens after maximum pupil dilation with tropicamide drops 0.5%
• The collected data were supplemented with the counting of patient records
• The dependent variable was retinopathy among diabetics patients examined
• The independent variables were represented by socio-demographic factors (age, sex, occupation, education level, marital status), cardiovascular risk factors (BMI, hypertension, smoking, sedentary lifestyle), features and other degenerative complications of diabetes (duration of diabetes, fasting glucose, other degenerative complications are neuropathy, nephropathy, diabetic foot), therapeutic modalities (insulin, oral antidiabetics, the combination of the two), ophthalmologic data (eye complaints, measurement of visual acuity, slit lamp examination, measurement of IOP and examination of the ocular fundus)
• Data analysis was done by software Epi Info version 3.5.3
• For quantitative variables, the averages were presented with a standard deviation; regarding the qualitative variables, the proportions were expressed
• The frequency comparisons were performed using the chi-2 Pearson test (or Fisher’s exact test as appropriate) and those averages using the student test. We performed a univariate analysis.
• For the different tests used, a p-value<0.05 was considered statistically significant
• The administrative authorities at various levels and the ethics committee gave their local agreement for carrying out the investigation
• The integrity of the patients was observed, the ophthalmologic examination was done in an appropriate setting
• All data collected during our investigation were used only in the context of this study and remained confidential
General characteristics of patients
• These diabetic patients had a mean age of 55.2 ± 12.3 years
• A female was predominated with sex ratio of 0.75
• Smoking was observed in 19 patients (10%), 67 patients (35.4%) were sedentary, 106 patients (56.1%) had hypertension and 111 patients (58.7%) overweight (Table 1)
|Level of instruction||0.199|
|Income Generating Activities (IGA)||0.298|
|Way of life||0.274|
|Live in couple||150||79.4|
Frequency of diabetic retinopathy
|Total||Effective||Frequency||Odds Ratio (IC 95%)||p|
|≤50||66||6||9.1||0.35 (0.45; 0.91)|
|Male||81||14||17.3||0.97 (0.45; 2.09)|
Risk factors associated with diabetic retinopathy
There was no link between gender and diabetic retinopathy. Smoking, physical inactivity, high blood pressure and body mass index were not associated with diabetic retinopathy (Tables 1 and 3).
|Total||Effective||Frequency||Odds Ratio (IC 95%)||p|
|Yes||19||3||15.8||0.87 (0.23; 3.1)|
|Yes||67||9||13.4||0.63 (0.27; 1.4)|
|No||83||13||15.7||0.7 (0.49; 2.32)|
|BMI? ? (Kg/m²)||0.097|
|<18.5||6||1||16.7||0.60 (0.06; 5.4)|
|≥25||111||14||12.6||1.30 (0.15; 12.74)|
In opposite, the duration of diabetes, the poor glycemic control of patients and kidney disease were associated with diabetic retinopathy (Table 4).
|Total||Effective||Frequency||Odds Ratio (IC 95%)||p|
|Seniority of diabetes (Years)||0.000|
|≤10||151||16||10.6||0.09 (0.03; 0.22)|
|[10-20]||32||14||43.7||0.11 (0.02; 0.63)|
|<1.26||64||6||9.4||0.36 (0.14; 0.93)|
|Yes||133||25||18.8||1.38 (0.58; 3.30)|
|Yes||137||30||21.9||4.57 (1.33; 15.73)|
|Yes||26||6||23.1||1.5 (0.55; 4.11)|
Risks factors associated with therapy
|Total||Diabetic Retinopathy (DR)||p|
|Type of treatment||0.114|
|ADO + Scheme||99||12||12.1|
|OAD + Insulin||87||20||23|
|Insulin alone + Scheme||3||1||33.3|
As concerned diabetic retinopathy, researches showed that pro-inflammatory cytokines and growth factors such as Vascular Endothelial Growth Factor (VEGF) contribute to the loss of blood retinal barrier and subsequently, to macular edema in various retinal pathologies, such as diabetic retinopathy .
Also, clinically, hyperglycemia induces proliferative changes in diabetic retinopathy synergistically with other risk factors for vascular diseases .
In the study of Tchabi et al.,  conducted in Parakou, northern part of Benin Republic in 2009 in the same unit, the prevalence of diabetic retinopathy was 36.6%. This difference could be due to the fact that in 2009, patients were not well followed through regular controls by an unit in charge of diabetics patients only; situation which exposed most of the diabetic patients to retinal complications.
Subjects younger than 50 years had a lower prevalence (9.1%) of diabetic retinopathy p=0.020 OR=0.35 IC 95% (0.45; 0.91) in opposite to those older than 50 years (21.9%). In many studies Hussain et al.,  and Moumen et al., , reported that older diabetics were more susceptible to diabetic retinopathy.
Sex did not influence the presence of retinopathy in our study, for instance male represented 17.3% p=0.955 OR=0.35 IC 95% (0.97; 2.09) and female 17.6%. The association between gender and diabetic retinopathy is variously appreciated by authors. For Yu et al.,  and Yang et al.,  there was no association between sex and diabetic retinopathy. In opposite, male gender was recognized as predisposing factor for retinopathy according to Mathengue et al., .
In our series, the consumption of tobacco, physical activity, blood pressure and body mass index were not associated with retinopathy. For instance, consumption of tobacco 15.8% with p=0.97 OR=0.87 IC 95% (0.23; 3.1), sedentarity 13.4% with p=0.279 OR=0.63 IC 95% (0.27; 1.4), absence of High blood pressure 15.7% with p=0.564 OR=0.7 IC 95% (0.49; 2.32), BMI≥25 12.6% with p=0.097 OR=1.30 IC 95% (0.15; 12.74).
Yang et al.,  found the same association between physical activity level and retinopathy. In opposite, Thapa et al.,  have reported that there is any association between tobacco consumption and retinopathy. The association between hypertension and diabetic retinopathy was variously appreciated. It was the same as concerned the body mass index. For Yu et al., , blood pressure would not influence the onset of retinopathy in diabetic patients. In opposite, in studies conducted by Kyari et al.,  and Moumen et al.,  diabetic patients with high blood pressure were more prone to complications such as retinopathy. Katulanda et al.,  had reported no association between retinopathy and body mass index whereas Kyari et al.,  reported that when the body mass index increased, the subjects were exposed to diabetic retinopathy.
According to Katulanda et al.,  prolonged exposure of patients with hyperglycemia was a risk factor for complications. This could explain the association between diabetes and retinopathy observed in the present study. Thapa et al., , Thomas et al., , Jingi et al.,  highlighted the same association. The imbalance of diabetes was a risk factor for complications. In this study, subjects with high blood sugar have developed over diabetic retinopathy. Rajalakshmi et al.,  stressed the same association.
Retinopathy and nephropathy share common etiologic mechanisms and settled simultaneously in diabetics. This observation would explain the association between retinopathy and nephropathy in patients of this study. Yu et al., , Rajalakshmi et al.,  and Abougalambou et al.,  highlighted the same association.
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Citation: Assavedo CRA, Codjo L, Alassani A, Adoukonou T, Codjo AP, et al. (2016) Risk Factors of Retinopathy Among Diabetics’ Patients in Benin in 2014. J Ophthalmic Clin Res 3: 025.
Copyright: © 2016 Codjo Rodrigue Abel Assavedo, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.