|Year : 2018 | Volume
| Issue : 1 | Page : 9-11
A comparative study on peripapillary retinal nerve fiber layer thickness in patients with iron-deficiency anemia to normal population
Shreya Jateen Jaiswal, Shashank Banait, Sachin V Daigavane
Department of Ophthalmology, Datta Meghe Institute of Medical Science, Wardha, Maharashtra, India
|Date of Web Publication||10-Sep-2018|
Dr. Shashank Banait
Department of Ophthalmology, JNMC, Wardha, Maharashtra
Source of Support: None, Conflict of Interest: None
Aims: The aim is to study the retinal nerve fiber layer (RNFL) thickness in patients of iron-deficiency anemia (IDA) and compare with healthy controls. Settings and Design: This study was conducted in the Department of Ophthalmology and Department of Medicine, Sawangi (Meghe), Wardha. This was a cross-sectional, observational study. Subjects and Methods: Eighty patients with IDA, i.e., hemoglobin: <10 g/dl, serum transferrin saturation: <15%, serum iron: <50 mg/dl, serum ferritin: <15 mic/dl, and total iron binding capacity (TIBC): >300 mic/dl and age- and sex-matched healthy individuals between 20 and 50 years of age were included in the study. All the cases and controls underwent detailed ophthalmic evaluation including optical coherence tomography (OCT). Hemoglobin, serum iron, serum transferrin saturation, serum ferritin, TIBC, and RNFL thickness by OCT were determined for both the groups and compared. Statistical Analysis Used: Descriptive and inferential statistics using Chi-square and students paired t-test. Analysis was done using the SPSS software (version 17.0) and GraphPad Prism 5.0 version software. Results: The RNFL thickness in all the four quadrants is lesser in patients of IDA. There is a positive correlation of RNFL thickness with hemoglobin, iron, and ferritin and negative correlation with TIBC. Conclusions: The difference in the average RNFL thickness in both the groups was statistically significant, with a decreased RNFL thickness in all the four quadrants was observed in the patients with IDA. It may greatly impact on the assessment and management of many ophthalmic disorders that affect RNFL thickness as glaucoma and other neuro-ophthalmological disorders.
Keywords: Iron-deficiency anemia, optical coherence tomography, peripapillary retinal nerve fiber layer thickness
|How to cite this article:|
Jaiswal SJ, Banait S, Daigavane SV. A comparative study on peripapillary retinal nerve fiber layer thickness in patients with iron-deficiency anemia to normal population. J Datta Meghe Inst Med Sci Univ 2018;13:9-11
|How to cite this URL:|
Jaiswal SJ, Banait S, Daigavane SV. A comparative study on peripapillary retinal nerve fiber layer thickness in patients with iron-deficiency anemia to normal population. J Datta Meghe Inst Med Sci Univ [serial online] 2018 [cited 2018 Sep 26];13:9-11. Available from: http://www.journaldmims.com/text.asp?2018/13/1/9/240907
| Introduction|| |
Anemia is a widespread public health problem, and the most common cause of anemia is iron deficiency.,, Iron-deficiency anemia (IDA) is more common, especially in women of childbearing age. IDA may have many deleterious effects in patients with ocular diseases through enhancement of effects of ischemia.
Iron besides playing an important role in oxygen transport also had additional roles in the central nervous system, including myelination, neurotransmitter synthesis, and neurometabolism. Thinning of retinal nerve fiber layer (RNFL) is reported in various studies conducted on women and children. The exact pathophysiology of fundus lesions is still unknown, but it has been suggested that it is related to hypoxia.,
The introduction of optical coherence tomography (OCT) has enabled in vivo quantitative analysis of peripapillary RNFL. It is a noninvasive imaging method that gives a high-resolution, cross-sectional topographic imaging of tissue by measuring backscattered light. It works on the principle of low coherence interferometry. Spectral domain-OCT (SD-OCT) has advantages of enhancement of image resolution, improvement of measurements, reducing the scan time, and reproducibility.
Accordingly, in the current study, we aimed to evaluate the effect of IDA on peripapillary RNFL thickness in the adult Indian population in comparison with age- and sex-matched healthy controls with SD-OCT and to establish correlation between peripapillary RNFL thickness and hematologic parameters in these individuals.
| Subjects and Methods|| |
The study has been conducted in accordance with the principles of the declaration of Helsinki and was approved by the Institutional Ethical Committee DMIMS (DU). Out of all the patients visiting the outpatient clinic in the Department of Ophthalmology and Medicine and patients admitted in the medicine wards with IDA were evaluated and 156 eyes of 80 cases and 158 eyes of 80 controls fulfilling the inclusion criteria were enrolled in the study.
Patients in the age group of 10–20 years were included in the study. IDA was diagnosed when hemoglobin (Hb) <10 g%, serum (Sr) iron ≤50 μg/dl, Sr. ferritin ≤15 μg/dl, and total iron-binding capacity (TIBC) ≥300.
Patients with best-corrected visual acuity <6/6, history of ocular trauma, history of intraocular operation, history of uveitis, e/o cataract, e/o glaucoma, e/o strabismus, e/o posterior segment pathology, amblyopia, signal strength <5 on OCT, anemia other than IDA, pregnant women, and patients not giving consent were excluded from the study.
OCT was done with Zeiss SD Cirrus TM HD-OCT MODEL-5000 to measure RNFL thickness in the peripapillary region sing optic nerve head and RNFL OU analysis: optic disc cube 200 × 200 scanning protocol.
Statistical analysis used
Descriptive and inferential statistics using Chi-square and students paired t-test. Analysis was performed using the SPSS software (the Statistical Package for the Social Sciences, version 17.0, SPSS Inc., Chicago, IL) and GraphPad Prism 5.0 version software (La Jolla, CA, USA).
Statistical significance was considered when the value of P < 0.05.
| Results|| |
The study included 156 eyes of 80 patients with IDA (mean age 29.76 ± 8.737) and age- and sex-matched 158 eyes of 80 healthy control participants (mean age 31.18 ± 8.383). Clinical and laboratory data of the patients are given in [Table 1]. There was no significant difference in the age and the cup-to-disc ratio in both the groups. There was a significant difference in the hemoglobin, serum iron, serum ferritin, and TIBC in both the case and the control group.
The OCT parameters are given in [Table 2], and there was a significant difference in the RNFL in all the four quadrants and thus the average RNFL.
A positive correlation was seen between average RNFL thickness and Hb and serum ferritin, and a negative correlation was seen with TIBC [Table 3].
|Table 3: Correlation between average retinal nerve fiber layer and various laboratory parameters|
Click here to view
| Discussion|| |
We have evaluated the RNFL thickness by OCT in adults with IDA and have compared the results with age- and sex-matched healthy controls.
The difference in the average RNFL thickness in both the groups is statistically significant, with a decreased RNFL thickness in all the four quadrants is observed in the patients with IDA. It may greatly impact on the assessment and management of many ophthalmic disorders that affect RNFL thickness as glaucoma and other neuro-ophthalmological disorders. A previous study conducted in adult females by Akdogan et al. showed thinning in the temporal and inferior quadrant, while Cikmazkara et al. suggested thinning in the inferior, temporal, and nasal quadrant and in a study by Moussa et al. found thinning in the superior, inferior, and nasal quadrant. While a study conducted on children with IDA by Türkyilmaz et al. showed thinning in the superior and inferior quadrant.
We have found a positive correlation between the average RNFL with Hb and serum ferritin levels in the case group, and a negative correlation is seen between the average RNFL with the TIBC levels. In a study by Moussa et al., a positive correlation was found between mean RNFL and Hb and serum iron. Cikmazkara et al. in their study found a positive correlation between mean RNFL and Hb, serum iron, serum ferritin, and transferrin saturation and a negative correlation between mean RNFL and TIBC. Akdogan et al. in their study found a positive correlation between inferior quadrant RNFL and Hb and between nasal quadrant RNFL to serum iron, serum ferritin, and TIBC.
The potential limitations of the study should be mentioned. Our study is hospital based which is located in Central India. The study population is, therefore, definitely not typical for the population of India as a whole. The sample size is small, and further larger studies are required to confirm these results. The patients were not subdivided into groups according to the duration of anemia, and thus, correlation with the same cannot be established. This is a cross-sectional study, we did not keep a follow-up of the patients and the RNFL was not reevaluated after iron supplementation, it was only a possible correlation.
As we could not establish the cause and effect relationship by this study, we recommend that population-based studies with a larger sample size should be conducted to reveal the clinical importance of these findings. A follow-up of patients to be kept, to reevaluate the RNFL thickness after iron supplementation and to see for any reversal of the changes that have occurred.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3]