Vol 11, No 3 (2022)
Observation letter
Published online: 2022-06-06

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Association between Red Blood Cell Distribution Width and Retinopathy in Patients with Type 2 Diabetes: A Cross-Sectional Study

Fateme Abshenas1, Gholamhosein Yaghoobi2, Ali Moradi34, Hassan Mehrad-Majd4, Mohammad Ali Yaghoubi5, Amirhossein Sahebkar6789
Clin Diabetol 2022;11(3):212-214.

Abstract

Not available

OBSERVATION LETTER

ISSN 2450–7458

e-ISSN 2450–8187

Association between Red Blood Cell Distribution Width and Retinopathy in Patients with Type ٢ Diabetes: A Cross-Sectional Study

Fateme Abshenas1Gholamhosein Yaghoobi2Ali Moradi34Hassan Mehrad-Majd4Mohammad Ali Yaghoubi5Amirhossein Sahebkar 6789
1Birjand University of Medical Sciences, Birjand, Iran
2Social Determinant Health Research Center, Birjand University of Medical Sciences, Birjand, Iran
3Orthopedic Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
4Clinical Research Development Unit, Ghaem Hospital, Mashhad University of Medical Sciences, Mashhad, Iran
5Metabolic Syndrome Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
6Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran
7Applied Biomedical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
8School of Medicine, The University of Western Australia, Perth, Australia
9Department of Biotechnology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran

Address for correspondence:

Mohammad Ali Yaghoubi

Metabolic Syndrome Research Center Mashhad University of Medical Sciences Mashhad, Iran

e-mail: yaghoubima@mums.ac.ir

Clinical Diabetology 2022, 11; 3: 212–214

DOI: 10.5603/DK.a2022.0023

Received: 10.04.2022 Accepted: 4.05.2022

It has been proposed that inflammation and oxidative stress play a crucial role in the pathogenesis of retinopathy and vascular complications in patients with diabetes [1]. High oxidative stress and inflammation may be a potential underlying mechanism for increasing the red blood cell distribution width (RDW) level and increased RDW can be considered a predictor of diabetes complications [2]. Considering the importance of diabetic retinopathy (DR) as a debilitating disease, the present study aimed to investigate the level of RDW as an inflammatory factor among patients with type 2 diabetes without retinopathy and with non-proliferative (NPDR) and proliferative retinopathy (PDR).

A total of 103 patients with type 2 diabetes were enrolled in this cross-sectional study. All patients underwent a comprehensive ophthalmological examination and were assigned into one of the three groups of: non-retinopathy (n = 37), non-proliferative retinopathy (n = 36), and proliferative retinopathy (n = 30). The demographic and clinical characteristics of the patients (n = 103), stratified by DR phenotype, including 37 non-retinopathy, 30 PDR and 36 NPDR, are listed in Table 1.

The overall mean age and duration of diabetes among non-retinopathy patient with diabetes were significantly lower compared to both NPDR and PDR patients. On the other hand, patients without retinopathy were almost 8–9 years younger compared to those with diabetic retinopathy (Tab. 1). Moreover, patients without retinopathy had a shorter history of diabetes compared to those with retinopathy, while those with PDR had the longest duration of diabetes (Tab. 1).

Table 1. Demographic and Clinical Characteristics of the Study Population

Retinopathy status

Diabetes without retinopathy

Proliferative retinopathy

Non-proliferative retinopathy

P

Gender

Male n (%)

12 (32.4)

12 (40)

18 (50)

0.31

Female n (%)

25 (67.6)

18 (60)

18 (50)

Age [years]

54.00 ± 9.27a

63.76 ± 5.97

62.25 ± 8.57

0.73

Duration of diabetes [years]

8.08 ± 5.78

20.47 ± 9.96

15.17 ± 8.69

< 0.01

Glycated hemoglobin [%]

8.64 ± 2. 21

9.55 ± 2.02

8.60 ± 2.52

0.02

Visual acuity

Right eye: 10.0 (8.1–10.0)b

Right eye: 6.0 (4.1–7.1)

Right eye: 8.1 (6.3–10.0)

< 0.01 (right eye)

Left eye: 10.0 (8.1–10.0)

Left eye: 6.1 (3.8–7.3)

Left eye: 8.1 (7.1–10.0)

< 0.01 (left eye)

Visual acuity showed a significant loss in NPDR (p = 0.017). It also dropped significantly to a lower degree in PDR (p < 0.0001) (Tab. 1). Patients with PDR had significantly higher glycated hemoglobin (HbA1c) compared to NPDR (p = 0.009) and non-retinopathy (p = 0.037) (Tab. 1, Fig. 1). Patients without retinopathy had a significantly lower RDW compared to those with both NPDR (p = 0.03) and PDR (p = 0.004). However, the difference in RDW between patients with NPDR and PDR was non-significant (p = 0.4) (Fig. 2). The total platelet count in NPDR and PDR (240.11 ± 62.26 and 237.33 ± 64.97, respectively) was non-significantly lower than those without retinopathy (265.89 ± 71.93) (Fig. 1). Moreover, no significant difference was found in platelet distribution width (PDW) between the three groups (non-retinopathy: 165.89 ± 71.93; NPDR: 240.11 ± 62.26; and PDR: 237.33 ± 64.97) (Fig. 1). The neutrophil to lymphocyte ratio (NLR) also showed no significant difference among the three groups (Fig. 1).

Figure 1. Visual Acuity of Non-Retinopathy, Proliferative Diabetic Retinopathy (PDR), and Non-Proliferative Diabetic Retinopathy (NPDR) Patients
The difference in visual acuity between the three groups was significant for both eyes except between the left eyes of non-retinopathy and NPDR patients
Figure 2. Comparison of Red Blood Cell Distribution Width (RDW), Platelet Distribution Width (PDW), Glycated Hemoglobin (HbA1c), and Neutrophil-to-Lymphocyte Ratio (N/L) among Patient with Diabetes without Retinopathy (NR), and with Non-Proliferative Diabetic Retinopathy (NPDR) and Proliferative Diabetic Retinopathy (PDR)
*Significant differences

A large body of evidence supports the association between RDW level and diabetic complications. Kurtul et al. demonstrated that RDW was significantly higher in patients with DR compared to those without [3]. However, unlike this study, no comparison was performed between patients with PDR and NPDR. In two studies conducted by Hanan et al. and Sherif et al. patients with DR had significantly higher RDW levels, compared to those in the control group and without macrovascular complications [4, 5].

In conclusion, RDW levels were higher in patients with DR compared to those without retinopathy, suggesting a possible association between RDW and DR. This study provides a valuable direction for further longitudinal studies with larger sample sizes in different populations to elucidate the possible causality relationship between RDW and DR.

Acknowledgements

The authors would like to thank the Research Dean, Birjand University of Medical Sciences, Birjand, Iran, and the Clinical Research Development Unit, Ghaem Hospital, Mashhad University of Medical Sciences for the scientific statistical consultation and support.

Ethics approval and consent to participate

Informed consents were obtained from the patients and the study was approved by Ethical Committee of Birjand University of Medical Sciences, Iran (ir.bums.rec.1397.302).

Conflict of interest

None declared.

References

  1. Al-Kharashi AS. Role of oxidative stress, inflammation, hypoxia and angiogenesis in the development of diabetic retinopathy. Saudi J Ophthalmol. 2018; 32(4): 318–323, doi: 10.1016/j.sjopt.2018.05.002, indexed in Pubmed: 30581303.
  2. Magri CJ, Fava S. Red blood cell distribution width and diabetes-associated complications. Diabetes Metab Syndr. 2014; 8(1): 13–17, doi: 10.1016/j.dsx.2013.10.012, indexed in Pubmed: 24661752.
  3. Kurtul BE, İnal B, Özer PA, et al. The Correlation Between Red Cell Distribution Width and Diabetic Retinopathy in Patients with Type 2 Diabetes Mellitus. Turkiye Klinikleri Journal of Ophthalmology. 2017; 26(1): 19–24, doi: 10.5336/ophthal.2016-50943.
  4. Mostafa AH, Hanan MA, Taghreed GM, et al. Red Cell Distribution Width as a Marker of Inflammation in Type 2 Diabetes Mellitus. The Medical Journal of Cairo University. 2018; 86(9): 2287–2295, doi: 10.21608/mjcu.2018.57522.
  5. Sherif H, Ramadan N, Radwan M, et al. Red cell distribution width as a marker of inflammation in type 2 diabetes mellitus. Life Sci J. 2013; 10(3): 1501–7.