Risk factors of ocular morbidity among under‐five years old children in Khartoum State‐ Sudan‐ 2020

Abstract Background and Aims Visual impairment in early childhood can significantly affect the development of visual, motor, and cognitive function and potentially lead to long‐term adverse psychosocial consequences. This study aimed to identify the risk factors of ocular morbidity among under 5‐year old children in Khartoum State, Sudan. Methods A cross‐sectional study was conducted in three tertiary eye care hospitals in Khartoum State, Sudan. The study included 391 children under the age of 5 years. The parent(s) were interviewed using a precoded, pretested, closed‐ended questionnaire that included questions regarding socio‐demographic profile and possible risk factors. Data were analyzed using Statistical Package for the Social Sciences (version 21.0). A P‐value of less than .05 was regarded as significant. Results There was a significant association between participants with diabetes mellitus and poor vision (P‐value <.001). Two‐thirds of participants (57%) with visual impairment had mothers, who reportedly attended antenatal care services regularly (P‐value .001), revealing a significant statistical association. Maternal diseases, specifically diabetes, was identified as a risk factor for poor visual acuity in their offspring (P‐value <.001). A significant relation was revealed between family history of eye disease and the degree of relationship to the affected participant (P‐value <.001). There was an association between watching TV and current visual acuity (P‐value <.001); as well as using mobile phones and current visual acuity (P‐value <.001). Multilinear analysis revealed the stronger influence of TV watching rather than the use of mobile phones (P‐value <.001). Conclusions Diabetes, diabetic mothers, a family history of ocular morbidity, watching television, and using mobile phones emerged as significant risk factors of ocular morbidity among children under the age of 5 years in this study. Many of these risk factors are either modifiable or controllable ocular morbidities among under‐five children can be reduced with suitable interventions.


| METHODS
Cluster sampling was used to draw the sample proportionate to the size of the study population at each hospital, where each hospital was considered as a cluster and then the number of participants was estimated proportionally according to hospital number of pediatric patients in the past 1 year. Convenience sampling was performed to select the participants, who fulfilled the inclusion criteria. These criteria included, being a boy or girl under 6 years of age, attending pediatric ophthalmology clinic to the first time, and his/her parent (s) voluntary agreed to participate in the study. All children of more than 5 years old were excluded.
Data were collected via interviews conducted onsite with one or more of the parents of the participants. The parent(s) were interviewed using a precoded, pretested, and closed-ended questionnaire that included questions related to socio-demographic data and possible risk factors identified in the literature. The questionnaire was pretested using pilot survey and modified accordingly, with insuring to include these participants in the study to avoid bias. Participants' clinical information was obtained from the consultant who performed the clinical examinations. We considered good vision as any visual acuity not worse than 6/12, poor vision as any visual acuity better than 6/12 and up to 3/60, and blindness as presenting visual acuity of less than 3/60 in the better eye.

| Data management and analysis
The data were sorted, cleaned, categorized, and summarized on a master sheet and then analyzed using Statistical Package for the Social Sciences (SPSS) version 21.0. The analysis encompasses descriptive univariate information, bi-variate analysis for crosstabulation using chi-square test for associations, and multilinear regression analysis for differences among the variables of interest. A P-value of less than .05 was regarded as significant.

| Ethics and permissions
The study was reviewed and approved by Albasar Institutional Review Board (B-IRB-20-MR-012). Permission to conduct the research was obtained from each hospital and informed written consent was obtained from the children's parent for both participation in the study and publication of the findings.
In this study, the anonymity of hospitals and patients was assured as only aggregated data is presented. All necessary measures were taken to ensure the confidentiality of the collected information. During the data collection, the records were never left unattended and they were stored in a locked room when not in use. Data were directly entered into a password protected master sheet.
All authors declare no conflict of interest and this study was not funded.

| RESULTS
The majority of the interviewees were the children's mothers (71%), a small majority (54%) of whom were housewives. Approximately a quarter (23%) of interviewees were fathers, where less than half (38%) were working at professional jobs and the remaining fathers were evenly spread among private, governmental, and physical labor Sudanese pounds per month and the mean number of family members was 4 (Table 1).
There was an association between diabetes mellitus (DM) and poor vision (P-value <.001) revealed by cross-tabulation test using Chi-square test (Table 2). Almost two-thirds (57%) of children with visual impairments had mothers, who reported regular attendance of antenatal care services, revealing a significant statistical association (P-value .001; Table 3). Mothers who reported having a disease during pregnancy exemplify a significant risk factor relating to eye morbidity, especially vision impairment in their offspring (Pvalue <.001).Among these diseases, DM was the most prevalent (Table 4). There was a significant association between the family history of eye diseases and the degree of relationship of the affected family member (P-value <.001; Table 5). The closer the relationship of the affected family member to the participant, the higher the risk of developing an eye disorder for that child. Refractive errors were the most common reported condition among family members.
Watching TV was strongly associated with current vision status (Pvalue <.001; Table 6). More than one-third (33%) of study participants reportedly used mobile phones. There was a significant association between the duration of mobile phone usage and poor vision, the longer duration of mobile phone usage associated with the frequency of participants with poor visual acuity (P-values <.001; Table 7). A multilinear regression analysis was performed to examine the relationship between TV watching and mobile use and visual acuity. This analysis revealed a significant difference in favor of TV watching making it a stronger associated risk factor for visual acuity (P-value <.001) in this study (Table 8). Note: P-value <.001.

| DISCUSSION
This study was conducted to identify the common risk factors associated with ocular morbidity among under-five children aiming to identify possible missed opportunities for prevention and control.
There were marginally more male participants in this study (male to female ratio was 1.1 to 1).These socio-demographic background of the interviewees is representative of Sudanese life in general. 12,13 The association between participants with DM and poor vision was expected as DM is a disease that affects the micro-capillaries of the body system and the retina is part of the affected tissues.
Bjornstad reported in his study that a major complication of DM in childhood is retinal and corneal changes that in turn affects vision due to early involvement of the micro-vessels. 14 Large disparities exist in perinatal health, not only between countries but also within cities and population groups. 15 The study yielded an unexpected association between the majority of participants with visual impairment and reported regular attendance of antenatal care services. Clearly, attendance of antenatal care services cannot be a risk factor so this finding is likely to be coincidental. The majority of early neonatal disorders are related to medically related factors that can be prevented and managed with the access to antenatal care services. The remaining problems of nonmedical risks such as social, mental, and barriers of access to proper care are factors that significantly hazardous to maternal and child health. 16 In this study, participants with poor visual acuity were significantly more likely to have mothers with DM. This finding is similar to other studies that link children's vision to maternal health status. A study by Borchertet al. report that children whose mothers had a history of maternal smoking during pregnancy were more likely (OR, 1.4) to have hyperopia and cessation of maternal smoking during pregnancy may reduce the risk of hyperopia in these children. 17 The literature documented a relation between maternal DM and the child health including vision. Intrauterine metabolic experiences continue to influence the neuro-developmental course in offspring of mothers with diabetes. Diabetes management and obstetric and neonatal care appear to effectively mitigate the potential long-term effects of most perinatal complications and morbidities. One study conducted by Rizzo revealed a borderline association between the children's scores on the psychomotor development index at 2 years of age and maternal third-trimester β-hydroxybutyrate levels. 18 Congenital hypoplasia of the optic nerve is consequent to maternal DM and it should be included in the differential diagnosis of visual field defects even when they are discovered in adults. 19 This study confirmed the association between a close member of the family, who has an eye disorder, and the visual acuity of participants. Refractive errors affecting first-degree relatives were the predominant type of eye disorders. There is strong evidence from the literature that, myopic parents are more prone to have myopic children. 20 The Orinda Longitudinal Study of Myopia (OLSM) revealed a significant association between parental myopia and the development of refractive error and axial length followed by myopia among their children. 21 Multiple studies have documented a higher prevalence of myopic children among families where both parents have myopia, while lower prevalence was noticed in families where no or only one parent is affected. [22][23][24][25][26][27][28] Ocular morbidity was associated with a family history of cataracts among first-degree relatives. 29 Juvenile cataract is a leading cause of VI in children. Cataract is a disorder that interrupts the passage of light due to disruption in the consistency of the lens. In young children, the pathophysiology is related to high-molecular-weight (HMW) protein aggregates and the some inherited genes, while in older ages, it is related to some environmental factors. The best visual outcome can be achieved with early surgical intervention in the first 6 weeks of age. 30  Watching TV for a long duration at this age is a significant risk to developing eye disorder(s). Nearly 40% of the study participants watch TV occasionally or for more than 2 hours per day. Watching TV showed significant association with current vision status. In addition, the multilinear regression analysis revealed that TV watching, more than use of a mobile phone, was the strongest factor linked to visual acuity in this sample. The study by Bener and et al. reported that low vision was more prevalent among frequent television viewers (17.2%) than in infrequent viewers (14.0%). The study also confirmed that the proportion of children who wear glasses was higher among those who were frequent TV viewers (21.3%). 37 In one Ethiopian study, sex, age, school type, television exposure duration, the distance of television exposure, mobile phone exposure, and medical visits were factors associated with visual impairment. Raising the level of awareness across community individuals toward early detection of VI and providing affordable eye healthcare services might reduce its prevalence. 38 Using mobile phones was another factor associated with an increased risk on visual acuity in this sample. Although 67% of study participants reportedly did not use mobile phones, there was a significant association between using mobile phone and poor vision. This association was more significant with those exposed to mobile phones for more than 2 hours per day. These findings confirm what was previously reported where smartphone use in children was strongly associated with pediatric dry eye disease (DED); whereas the prevalence of DED is related to the longer mean daily duration of smartphone use. 39,40 DED is public health concern that results in a multifaceted