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The impact of diabetes control, type, duration, and
family history on visual impairment |
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Authors Khalil Ali Ibraheim1-4 |
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Affiliations 1Department
of Surgery, Faculty of Medicine, University of Kordofan, EL-Obeid, Sudan. 2Doctor
Khalil Ophthalmology Center, El-Obeid, Sudan. 3El-Obeid
Teaching Hospital, Ophthalmology Department, El-Obeid, Sudan. 4Medicine
program, Sheikan College, El-Obeid, Sudan. ABSTRACT |
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Edited By: Eldisugi Hassan M. Humida Kordofan University, El-Obeid, Sudan Reviewed by:
- Charalambos M. Prof MRCC, Manchester, UK - Esraa Dafallah University of Kordofan,
El-Obeid, Sudan Correspondence to: Khalil Ali
Ibraheim. Email: drkhalil74@gmail.com ORCID: 0000000301369611 Received on:
17/11/2025 Accepted on:
13/12/2025 Published on:
19/12/2025 Citation Ibraheim KA.
The impact of diabetes control, type, duration, and
family history on visual impairment. Medical
Research Updates Journal 2025;3(4):1-8. doi.org/10.70084/mruj.0043.P234. |
Background: November 14 is the International United
Nations (UN) Day to promote patient health education and professional
training to reduce diabetes-related blindness. Due to economic hardship, drug
shortages, and medical personnel exodus, Sudan's three-year war impairs
diabetes glycemic management. To address these difficulties, we examined the
impact of glycemic control in conflict zones, where many factors contributed
to the deterioration of vision among diabetic patients. Methodology:
This prospective descriptive study was conducted between May 15, 2025, and
October 20, 2025, at Doctor Khalil Clinic, located in El-Obeid, North
Kordofan, Sudan. The study encompassed all individuals with diabetes who
visited the clinic for follow-up related to ophthalmic complaints. Visual
acuity (VA) was evaluated for 120 individuals, including all patients
exhibiting uncorrected poor vision, regardless of the use of glasses or other
means of correction. A comprehensive ophthalmic examination was conducted
utilizing a slit lamp, ophthalmoscope, 90D lens, A-scan, and optical
coherence tomography (OCT). Blood tests, including fasting blood glucose and
HbA1C, were performed to determine the causes of poor vision. Results:
This study analyzed 120 patients with impaired vision, comprising 70 females
(58%) and 50 males (42%), resulting in a female-to-male ratio of 1.40:1.00.
The age group most affected was 65-70 years, accounting for 38% of the
sample. Type 2 diabetes (T2DM) is prevalent in 88% of patients, with 70%
having diabetes durations exceeding 10 years. Additionally, 75% of patients
utilized tablets for glycemic control, while fasting blood glucose (FBG) and
HbA1c levels were elevated in 62% and 58% of patients, respectively. Conclusion:
Because of the war in Sudan, most diabetic patients encounter
difficulties in maintaining glycemic control, which deteriorates their
vision. |
Keywords: glycemic
control, diabetes, low vision, Sudan, Visual acuity
INTRODUCTION
World Diabetes Day, held on November
14 each year by the UN, focuses on patient health education and professional
training to prevent diabetes-related blindness. The nearly three-year war in
Sudan has negatively impacted diabetes glycemic control due to economic
challenges, a shortage of essential drugs, and the emigration of most medical
staff. These factors together impacted most patients with comorbidities in most
parts of the Sudan. Diabetes, particularly T2DM, is one of the most comorbid
diseases that needs continuous control. Thus, diabetic patients must control
their FBG and HbA1c to reduce eyesight deterioration and improve quality of
life [1], because these are important factors in modulating the
complications of diabetes and preserving the patient's reserve vision.
Accordingly, one study stated that patient education is essential to increase
their knowledge and awareness of glycemic control and nutrition [2]. Patient
education and the availability of essential diabetic drugs are important factors
because knowledge about the disease raises awareness of its complications.
Furthermore, the study on glycemic control concentrates on health coaching to
decrease blood sugar and recommends doing further evidence-based studies [3].
Additionally, health coaching is an important method for controlling diabetes,
and a study demonstrated a significant decrease in HbA1c levels and
improvements in diet after 6 months of coaching, leading to recommendations for
further research on health coaching with higher-quality evidence [4]. As
the war is one of the most important factors for depression, one study finds a
strong association between depression and poor glycemic control and recommends
further longitudinal studies to explore the mechanism underlying these associations
[5]. Also, the intermittent fasting regimen emerges as an important tool for
glycemic control, but in this study, they recommend constant monitoring to
reduce the risk of hypoglycemia and its related
complications [6]. This study investigated the impact of impaired glycemic
control on ocular health in conflict zones, where numerous factors impair
diabetic patients.
MATERIALS
AND METHODS
This prospective descriptive study
was conducted from May 15, 2025, to October 20, 2025. The study was conducted
in Doctor Khalil Clinic, located in El-Obeid, North Kordofan, Sudan. This study
encompassed all diabetic individuals who attended the clinic for follow-up (120
patients). We evaluated their VA and identified all individuals with
uncorrected suboptimal vision, regardless of corrective measures such as
glasses or alternatives. An exhaustive ophthalmic evaluation was conducted
utilizing a slit lamp, ophthalmoscope, 90D lens, A-scan, and optical coherence
tomography (OCT). Moreover, blood tests, such as FBG and HbA1C, were performed
to ascertain the causes of impaired vision.
Data Analysis
Data sets were imported into the
Statistical Package for Social Sciences (SPSS Inc., Chicago, IL, version 24),
from which frequencies, percentages, and cross-tabulations were computed.
RESULTS
This study examined 120 patients with
poor vision: 70 were females (58%) and 50 were males (42%), resulting in a
female-to-male ratio of 1.40:1.00. The most affected age group was 65-70 years
(38%), followed by those over 70 years (30%), and then both the age groups <
50 years and 60-64 years (26%); see Table1.
Table 1 demonstrates the distribution of
gender in the age group of the study populations.
|
Age group |
Males |
Females |
Total |
|
<60 years |
14 |
12 |
26 |
|
60-64 |
8 |
18 |
26 |
|
65-70 |
16 |
22 |
38 |
|
>70 |
12 |
18 |
30 |
|
Total |
50 |
70 |
120 |
In relation to visual acuity (VA),
the most common category was VA <6/60, accounting for 68%, followed by VA
6/60 at 26%, VA 6/24 at 14%, and finally VA 6/36 at 12%. Refer to Table 2.
Table 2 demonstrates the distribution of the
VA in the age group of the study populations.
|
Age group |
6/24 |
6/36 |
6/60 |
<6/60 |
Total |
|
<60 years |
0 |
4 |
6 |
16 |
26 |
|
60-64 |
2 |
2 |
8 |
14 |
26 |
|
65-70 |
8 |
2 |
8 |
20 |
38 |
|
>70 |
4 |
4 |
4 |
18 |
30 |
|
Total |
14 |
12 |
26 |
68 |
120 |
Regarding
the distribution of factors affecting diabetic patients with low vision, type 1
diabetes mellitus (T1DM) was found in 14 patients (12%), including 12 (86%)
males and 2 (14%) females. T2DM was found in 106 patients (88%), including 38
males (36%) and 68 females (64%). Regarding duration, most patients have had
diabetes for more than 10 years, totalling 84 patients (70%), comprised of 30
males (36%), and 54 females (64%). About 36 patients have had diabetes for 10
years or less (30%), including 20 males (56%) and 16 females (44%). Referring
to diet, tablets, and insulin. Only 4 patients (3%) used diet control,
involving 2 males and 2 females. Tablets were used by 90 patients (75%),
comprising 36 males (40%) and 54 females (60%). Insulin was used by 26 patients
(22%), including 12 males (46%) and 14 females (54%). FBG was abnormal in 74
patients (62%), including 34 males (46%) and 40 females (54%). About 62 (52%)
patients have a family history of diabetes, including 18 males (29%) and 44
females (71%), while 58 patients (48%) do not have a family history, comprising
32 males (55%) and 26 females (45%). See Table 3 and Figure 1.
Table 3 shows the gender distribution of
factors that affect glycemic control.
|
Variable |
Males |
Females |
Total |
|
|
Type of diabetes |
T1DM |
12 |
2 |
14 |
|
T2DM |
38 |
68 |
106 |
|
|
Duration of |
≤10 years |
20 |
16 |
36 |
|
>10 years |
30 |
54 |
84 |
|
|
Type of control |
Diet |
2 |
2 |
4 |
|
Tabs |
36 |
54 |
90 |
|
|
Insulin |
12 |
14 |
26 |
|
|
FBG |
Normal |
16 |
30 |
46 |
|
Abnormal |
34 |
40 |
74 |
|
|
HBA1c |
Normal |
22 |
28 |
50 |
|
|
Abnormal |
28 |
42 |
70 |
|
Family history |
Yes |
18 |
44 |
62 |
|
|
No |
32 |
26 |
58 |

Figure 1 illustrates the proportion of gender
distributed by factors affecting glycaemic control.
Regarding
the distribution of factors affecting diabetic patients by age group, we
observe that among those with diabetes, 88% have T2DM, and the most affected
age group was 65–70 years old, represented by 35%. The remaining 12% have T1DM,
with the most affected age group being those under 60 years old.
Regarding
the duration of diabetes, 70% of patients have had the disease for more than 10
years, while 30% have had it for less than 10 years. People with diabetes for
more than 10 years are mostly between the ages of 65 and 70 (33%), while people
with diabetes for less than 10 years are mostly between the ages of 60 and 64
(33%). In terms of glycemic control, most patients manage their blood glucose
with tablets (74%), followed by insulin (22%) and diet (3%). Among tablet
users, the most common age group was 65–70 years, at 40%. Concerning fasting
blood glucose, it was mostly high in the 65–70-year-old group at 30% and mostly
normal in the same age group at 35%. As for HbA1c, it was mostly high in the
<59-year group at 31% and mostly normal in the 65-70-year group at 44%. A
family history of diabetes was present in 52% of patients, mostly in the
65-70-year-old group at 32%.
Table 4 shows the distribution of age by
factors affecting glycemic control.
|
Category |
Variable |
<60 years |
60-64 |
65-70 |
>70 |
Total |
|
Diabetes type |
T1DM |
10 |
2 |
2 |
0 |
14 |
|
T2DM |
16 |
24 |
36 |
30 |
106 |
|
|
Duration |
≤10 years |
10 |
12 |
10 |
4 |
36 |
|
>10 years |
16 |
14 |
28 |
26 |
84 |
|
|
Control type |
Diet |
2 |
0 |
0 |
2 |
4 |
|
Tabs |
14 |
16 |
36 |
24 |
90 |
|
|
Insulin |
10 |
10 |
2 |
4 |
26 |
|
|
FBG |
Normal |
6 |
14 |
16 |
10 |
46 |
|
Abnormal |
20 |
12 |
22 |
20 |
74 |
|
|
HBA1c |
Normal |
4 |
14 |
22 |
10 |
50 |
|
|
Abnormal |
22 |
12 |
16 |
20 |
70 |
|
Family history |
Yes |
10 |
14 |
20 |
18 |
62 |
|
|
No |
16 |
12 |
18 |
12 |
58 |

Figure 2 shows the proportion of age by factors
affecting glycaemic control.
DISCUSSION
According to the findings of this
study we found that the most common type of diabetes in the group is type 2
diabetes that constitute about 88% of the patients, and we find that incidence
of decrease vision was increased when the duration of diabetes was increased,
in this study we find that the patients with duration of more than 10 years
constitute 70%, so this high percentage was due to methodology of this study so
we select patients with low vision, so most of the patients were elderly with
long duration, in one study stated that the complications of diabetes that lead
to decrease vision such as diabetic retinopathy will increased when the
duration of diabetes was increased, and also affect other factors that lead to
decreased vision such and maculopathy and macular oedema[7], in study found
that longer duration of diabetes (more than ten years) was associated
with poor glycaemic control and it was found to be 7 times higher among
diabetic patients with a duration of less than 10 years[8]. Most patients used tablets for glycemic
control, accounting for 75% of the group, indicating that tablet use is
predominant in this study and contributes to low glycemic control. FBG is
abnormal in 62% of the patients, and HbA1c is abnormal in 58% of them. All
these factors were affected by the war; most of the patients were unable to
reach the health facility or obtain bad-quality drugs, and some stopped drugs.
As a result, the standard deviation of the FBG is huge (SD = 49.3), while the
standard deviation of HbA1c is 2.17; the mean FBG was 152.5, and the mean HbA1c
was 8.6. In one study, the researchers found that the mean HbA1c was similar to that of our study, which was 8.9 with an SD of
1.6 [9]. Concerning diet control, only 4% of the patients used this type of
glycemic control. A systematic review and meta-analysis concluded that dietary
control of diabetes or prediabetes, using a prebiotic and a Mediterranean diet,
is beneficial for improving gut microbes that help control FBG and HbA1c,
although the mechanisms remain uncertain due to limited reports [10]. In our
situation, due to war, we may benefit from telemedical intervention that was
found to be of benefit in decreasing HbA1c concentrations, as found in a
systematic meta-review [11]. Certain mechanisms, such as the increased
incidence of diabetic retinopathy, cataracts, and glaucoma, affect diabetic
patients' vision when they have poor glycemic control and high FBG. All factors
influence the decreasing vision in diabetic patients, so in this study, the
mean FBG was found to be 152.5 with a standard deviation of 49.3. In this
study, the primary mechanism for decreasing vision in diabetic patients with
high FBG and HbA1c levels is the development of diabetic retinopathy, which is
the main factor contributing to vision loss in diabetics; it was noted that
controlling these two factors can reduce the occurrence of diabetic retinopathy
[12]. Therefore, this experiment led us to the importance of regular eye exams
and checks of the FBG and HbA1c levels. In one cohort prospective study, it was
stated that intensive glycemic control did not affect or correlate with changes
in diabetic retinopathy, which is the major factor for decreased vision;
further studies were recommended [13]. However, our study discovered a correlation
between poor glycemic control and reduced vision. This study assessed glycemic
control in individuals with type 2 diabetes using HbA1c. Their sample was
larger than my study (290), but the percentage of females was relatively
similar to our study, 58%. The mean (SD) age in their study was 54.9 (12.8),
while in our study, the mean (SD) age was 64.9 (10.9), which is slightly higher
because our sample includes patients with poor vision, indicating a longer
duration of diabetes and the presence of complications. This was clear in the
mean (SD) duration of diabetes, which was 6.8 (5.5) years, but in our study
14.3 (5.9), concerning drugs for glycemic control, as our study (72.8%) used
oral hypoglycemic drugs versus 75% in our study, and 21.4% used insulin compared
to 22% in our study [14]. A study conducted in northern Sudan concluded that
most patients have uncontrolled diabetes, are older, and are predominantly
female, which aligns with our findings of female gender predominance, an older
mean age, and nearly all patients having complications [15].
LIST OF ABBREVIATIONS
|
Abbreviation |
Full term |
|
UN |
United nations |
|
T1DM |
Type 1 diabetes mellitus |
|
T2DM |
Type 2 diabetes mellitus |
|
AB scan |
AB ultrasonography |
|
OCT |
Ocular coherent tomography |
|
90D |
90 diopter lenses |
|
VA |
Visual acuity |
|
HBA1c |
Glycated hemoglobin A1c |
|
FBG |
Fasting blood glucose |
ACKNOWLEDGEMENT
The author would like to thank all patients for their cooperation, as well as the staff at Doctor Khalil's clinic, who assisted in data collection.
FUNDING
The Prof.
Medical Research Consultancy Center (PMRCC) funded this project. Grant Number:
PMRCC/2024A7.
CONFLICT OF INTEREST
The author
declares that they have no conflict of interest to disclose.
ETHICAL CONSIDERATIONS
Ethical
approval was obtained from the Doctor Khalil Ophthalmology Center, and the clinic
administration received administrative authorization before data collection.
The study adhered to the principles of confidentiality and responsible use of
routinely collected health information.
ETHICAL APPROVAL
The protocol
of this study had been approved by the Human Ethics Committee at Prof MRCC.
Approval number: HREC 0007/MRCC.3/24).
DISCLOSURE
This
research was conducted without the use of artificial intelligence or assisted
technologies, including the generation of figures.
DATA AVAILABILITY
The data
supporting the conclusions of this article are included within the article, and
further inquiries can be sent to the corresponding author.
AUTHOR’S CONTRIBUTION
Ibraheim:
Conceptual, study design, data collection, manuscript drafting, and approval
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