Refractive errors among Saudi college students and associated risk factors

The Incidence and Severity of Myopia in the Population of Medical Students and Its Dependence on Various Demographic Factors and Vision Hygiene Habits

(1) Background: Myopia is one of the leading causes of visual impairment. Visual work and usage of electronic devices are known risk factors of myopia. Many education systems were forced to apply online and hybrid teaching methods, to reduce the number of new cases of COVID-19. Medical students are a population well-known for intense visual work in the form of learning; (2) Methods: Visual acuity and refractive error were measured in the population of medical students. Participants also filled out the survey that included their population characteristic and their habits related to the hygiene of vision; (3) Results: We found a correlation between the age of the first diagnosis of myopia and current values of refractive error. The majority of participants believe that the COVID-19 pandemic had an impact on the health of their vision. Among methods of studying, usage of the computer screen was less preferred by myopic students; (4) Conclusions: In the population of medical school students in Eastern Poland, visual acuity was lower than 1.0 in 232 (52.97%) in the right eye and 234 (53.42%) in the left eye. Early recognition of refractive error has influenced its current values. Among methods of studying, usage of the computer screen was less preferred by myopic students. More population-based studies should focus on the impact of the COVID-19 pandemic on the health of vision.

Perspectives and clinical practices of optometrists in Saudi Arabia concerning myopia in children

AIM

To investigate the practice patterns of optometrists in Saudi Arabia regarding myopia management.

METHODS

An internet-based survey was distributed to all practicing optometrists in Saudi Arabia (n=1886). The survey contained questions related to 1) demographics, 2) knowledge about myopia and its associated complications, 3) current clinical care, 4) type and frequency of myopia treatment prescribed, and 5) potential barriers limiting treatment adoption.

RESULTS

The completed surveys were collected from 171 optometrists (9.06% response rate, 60% male). Knowledge regarding myopia-associated complications was prevalent but somewhat inaccurate among the respondents. Cycloplegic refraction at initial visit was used by 59% of the respondents. The cover test was the most reported binocular vision test (83%), and 38% of optometrists did not perform any ocular biometrics. Two-thirds prescribed single-vision spectacles for children with myopia. Increased time spent outdoors was selected by 80% of the practitioners who prescribed myopia control treatment as the primary approach. Insufficient support and lack of clinical experience in providing myopia treatment were reported as the most important factors limiting the adoption of myopia management strategies.

CONCLUSION

The current optometric practices in Saudi Arabia require further investigation. Optometrists appear to be somewhat aware of myopia and the associated risks. However, most evidence-based myopia treatments are not being locally adopted, primarily because of lack of support, lack of experience, and limited availability.

Myopia and Near Work: A Systematic Review and Meta-Analysis

BACKGROUND

Myopia is a global public health problem affecting quality of life and work productivity. Data is scarce regarding the effects of near work on myopia. Providing a larger meta-analysis with life-long perspective, including adults and occupational exposure seemed needed.

METHODS

We searched PubMed, Cochrane Library, Embase and Science Direct for studies reporting myopia prevalence in near work. Myopia was defined as a mean spherical equivalent ≤ -0.50 diopter. We performed a meta-analysis using random-effects model on myopia prevalence, myopia progression per year, and odds ratio (OR) of myopia in near work, completed by subgroup analyses and meta-regressions on patients' characteristics, type of work in adults, geographic zones, time and characteristics of near work.

RESULTS

We included 78 studies, representing a total of 254,037 participants, aged from 6 to 39 years. The global prevalence of myopia in near work was 35% (95% CI: 30 to 41%), with a prevalence of 31% (95% CI: 26 to 37%) in children and 46% (95% CI: 30 to 62%) in adults. Myopia progression was -0.39 diopters per year (-0.53 to -0.24 D/year), ranging from -0.44 (-0.57 to -0.31) in children to -0.25 D/year (-0.56 to 0.06) in adults. The odds of myopia in workers exposed vs. non-exposed to near work were increased by 26% (18 to 34%), by 31% (21 to 42%) in children and 21% (6 to 35%) in adults. Prevalence of myopia was higher in adults compared to children (Coefficient 0.15, 95% CI: 0.03 to 0.27).

CONCLUSIONS

Near work conditions, including occupational exposure in adults, could be associated with myopia. Targeted prevention should be implemented in the workplace.

Transpalpebral intraocular pressure measurement by Diaton compared to Goldman applanation tonometer in myopic eyes before and after transepithelial photorefractive keratectomy in Saudi Arabia

AIM

To compare intraocular pressure (IOP) measured via the trans palpebral IOP (tpIOP) method using a Diaton or with a Goldman applanation tonometer (GAT) and study the determinants of IOP difference in eyes undergoing transepithelial photorefractive keratectomy (TPRK) for myopia.

METHODS

This cross-sectional validation study was held in 2020 in an eye hospital in Saudi Arabia. IOP was measured by Diaton and GAT before treatment, after one week, and one month of TPRK. It is considered if IOP difference by Diaton and GAT was less than ±2 mm Hg acceptable. The IOP difference was tested if correlated to spherical equivalent (SE), central corneal thickness (CCT), age, gender, or tpIOP.

RESULTS

Totolly 200 myopic eyes of 100 patients were included in the study. The mean difference of IOP measured by two methods before TPRK, 1wk, and 1mo after TPRK were 0.790, -0.790, and -0.920 mm Hg, respectively (P<0.001). Diaton could measure IOP effectively 89.5% eyes before TPRK and 82% and 84% at 1wk and 1mo after TPTK, respectively. At week 1, IOP differences were significantly correlated to baseline CCT (P=0.02) and tpIOP at week 1 (P<0.001). One month after TPRK, only tpIOP was significantly correlated to the difference in IOP (P<0.001).

CONCLUSION

Diaton is a good screening tool for IOP before TPRK. It helps in monitoring IOP after surgery. Although more practical, it is less efficient than GAT. In eyes with high myopia and low tpIOP before surgery, IOP post-TPRK by Diaton and GAT could differ.

The prevalence of refractive errors in college students in Israel

PURPOSE

To determine the prevalence of refractive errors in Jewish and Arab college students in Israel and associations with ethnicity and sex.

METHODS

In this retrospective cross-sectional study, first-year college students underwent non-cycloplegic autorefraction and answered a questionnaire to assess age, sex, and self-identified ethnicity. Spherical equivalent refractive error (SER) was calculated, and the prevalence of hyperopia (>+0.50 Diopter, D), emmetropia (>-0.50 to +0.50 D), myopia (≤-0.50D, low ≤-0.50 to >-3.0D, moderate <-3.0 to >-6.0D, high ≤-6.0D), and astigmatism (>0.50D) were determined. Groups were compared using Chi-square or Fisher test. Univariate and multivariate analyses were conducted to identify factors associated with refractive errors.

RESULTS

Participants (n = 807) had a mean age of 22.1 ± 2.6 years (range: 17-30 years) and SER of -1.7 ± 2.2D (range: -13.3 to +5.7D). The prevalence and 95% confidence internal of myopia was 66.3% (63.0-69.6). Jewish students had a higher prevalence than Arab students for myopia (69.2% vs 60.3%), moderate (18.5% vs 12.2%) and high myopia (5.9% vs 1.9%) and astigmatism (51.4% vs 43.9%, p<0.05 for all), but not low myopia or hyperopia. Females had a higher prevalence of myopia than males (68.1% vs 58.7%, p<0.03). Jewish ethnicity was associated with myopia (OR=1.48, p = 0.01) and moderate myopia (OR=1.72, p = 0.01), and studying optometry was associated with moderate myopia (OR=1.63, p = 0.02). Sex and age were not associated with myopia.

CONCLUSION

Myopia prevalence in Israeli college students is high, showing associations with Jewish, but not Arab, ethnicity, suggesting that ethnic factors may play a role in the refractive differences between Arabs and Jews.

The Clinical Characteristics of Amblyopia in Children Under 17 Years of Age in Qassim Region, Saudi Arabia

Purpose

To provide the clinical characteristics of amblyopia in children under 17 years of age in Qassim Region, Saudi Arabia.

Patients and Methods

The study was a cross-sectional hospital-based, included 121 children with amblyopia aged between 3 and 17 years, referred from 6 hospitals in Qassim region to the paediatric optometry clinic at Qassim University medical city. Demographics and comprehensive ocular examination including visual acuity (VA), assessment of anterior and posterior segment, cycloplegic refraction (RE), angle of deviation, and cause of amblyopia were collected.

Results

The mean age at diagnosis of amblyopia was 8.93 ± 3.67 years. The leading cause of amblyopia was strabismus and anisometropia shared the same percentage at 29.75%, and the combined-mechanism at 18.18%. Amblyopia was more common in males 57.85%, particularly strabismic amblyopia in 66.67% and anisometropic amblyopia in 61.11%, p = 0.408. Amblyopia was more predominant in the age group 6- to 9-year-old, particularly, strabismic amblyopia 44.44%, and amblyopia due to a combined mechanism of 36.36%, p = 0.066. The degree of hyperopia was not varied by the cause of amblyopia (P = 0.401), with slightly high hyperopia found in ametropic and strabismic amblyopia. Conversely, hyperopic astigmatism was significantly associated with amblyopia P = 0.020, with a high degree of hyperopic astigmatism found in meridional amblyopia and ametropic amblyopia.

Conclusion

The commonest types of amblyopia in children were attributed to strabismus and anisometropia. Causes of amblyopia differed by age group with strabismus, anisometropia, and combined mechanism accounting for most children aged 6- to 9-years and strabismus for children aged less than 6 years. Hyperopic and myopic astigmatism were significantly associated with anisometropia and meridional amblyopia. Therefore, efforts should be made for early diagnosis and management of childhood amblyopia and uncorrected refractive errors to avoid their impact on quality of life.

Association between digital smart device use and myopia: a systematic review and meta-analysis

BACKGROUND

Excessive use of digital smart devices, including smartphones and tablet computers, could be a risk factor for myopia. We aimed to review the literature on the association between digital smart device use and myopia.

METHODS

In this systematic review and meta-analysis we searched MEDLINE and Embase, and manually searched reference lists for primary research articles investigating smart device (ie, smartphones and tablets) exposure and myopia in children and young adults (aged 3 months to 33 years) from database inception to June 2 (MEDLINE) and June 3 (Embase), 2020. We included studies that investigated myopia-related outcomes of prevalent or incident myopia, myopia progression rate, axial length, or spherical equivalent. Studies were excluded if they were reviews or case reports, did not investigate myopia-related outcomes, or did not investigate risk factors for myopia. Bias was assessed with the Joanna Briggs Institute Critical Appraisal Checklists for analytical cross-sectional and cohort studies. We categorised studies as follows: category one studies investigated smart device use independently; category two studies investigated smart device use in combination with computer use; and category three studies investigated smart device use with other near-vision tasks that were not screen-based. We extracted unadjusted and adjusted odds ratios (ORs), β coefficients, prevalence ratios, Spearman's correlation coefficients, and p values for associations between screen time and incident or prevalent myopia. We did a meta-analysis of the association between screen time and prevalent or incident myopia for category one articles alone and for category one and two articles combined. Random-effects models were used when study heterogeneity was high (I²>50%) and fixed-effects models were used when heterogeneity was low (I²≤50%).

FINDINGS

3325 articles were identified, of which 33 were included in the systematic review and 11 were included in the meta-analysis. Four (40%) of ten category one articles, eight (80%) of ten category two articles, and all 13 category three articles used objective measures to identify myopia (refraction), whereas the remaining studies used questionnaires to identify myopia. Screen exposure was measured by use of questionnaires in all studies, with one also measuring device-recorded network data consumption. Associations between screen exposure and prevalent or incident myopia, an increased myopic spherical equivalent, and longer axial length were reported in five (50%) category one and six (60%) category two articles. Smart device screen time alone (OR 1·26 [95% CI 1·00-1·60]; I²=77%) or in combination with computer use (1·77 [1·28-2·45]; I²=87%) was significantly associated with myopia. The most common sources of risk of bias were that all 33 studies did not include reliable measures of screen time, seven (21%) did not objectively measure myopia, and nine (27%) did not identify or adjust for confounders in the analysis. The high heterogeneity between studies included in the meta-analysis resulted from variability in sample size (range 155-19 934 participants), the mean age of participants (3-16 years), the standard error of the estimated odds of prevalent or incident myopia (0·02-2·21), and the use of continuous (six [55%] of 11) versus categorical (five [46%]) screen time variables INTERPRETATION: Smart device exposure might be associated with an increased risk of myopia. Research with objective measures of screen time and myopia-related outcomes that investigates smart device exposure as an independent risk factor is required.

FUNDING

None.

Visual Function of Drivers and its Relation to the Occurrence of Road Traffic Accidents in Saudi Arabia

BACKGROUND: The mortality rate due to road traffic accidents (RTA) is significantly high in Saudi Arabia (SA) compared to other countries. The visual function which includes good visual acuity (VA) and binocular vision are very important factors that can contribute to the incidence of RTA. AIM: The aim of this study is to investigate the association between refractive errors (REs) and the RTA in SA. METHODS: A total of 354 participants (mean age 22.67 ± 3.22 years) were recruited randomly to participate in this study from the population of Qassim district. Data collected using the questionnaire included participants’ age, sex, and education level, ocular and medical history, driving history as well as history of RTA. Ocular health examination including VA, RE measurements, and binocular vision function vision was measured and analyzed. RESULTS: The results of this study show that 48.3% of drivers had some form of REs with 3.4% being visually impaired. 217 (61.3%) of participants have had an RTA, and 119 (54.9%) of them have had more than two accidents in the past two years. The findings show no significant association between the occurrence of RTA and uncorrected REs or binocular vision dysfunction. CONCLUSION: Our data showed significantly higher rate of RTA among Saudi drivers which is much higher than any country in the world. The current Saudi regulations for obtaining driving license need to be modified, with implementing a comprehensive eye examination prior to acquiring or renewing drivers’ licenses.

Visual status among undergraduate students: Findings from an emerging university in Saudi Arabia

BACKGROUND

Refractive error is an important preventable cause of visual impairment and blindness worldwide. In adult life, reduced vision can potentially affect the academic performance, choice of occupation and socio-economic status. This study aimed to assess the prevalence of refractive errors and related visual impairment among undergraduate male students in Prince Sattam bin Abdulaziz University in Al-Kharj, Saudi Arabia.

METHODS

A descriptive cross-sectional study was employed in the current work. After obtaining an informed consent; each eligible student was asked to fill a self-constructed survey and have screened in the college premises for visual acuity and refractive error. Candidates detected with defective vision have been referred for further examination at well-equipped ophthalmology clinic in the University Hospital.

RESULTS

A total of 420 undergraduate students, with age ranged from 18 to 30 years, have participated in the current study. About 25.0% of the participants have used spectacles at the time of examination. Positive family history of spectacles use was found in 71.4%. Our study showed that visual acuity in the better eye was low in 34.76% of the participants. Seventy-eight students (18.6%) of the total participants reported defective vision and have fulfilled refractometric examination. Of the examined students 83.3% were found to have refractive errors. Astigmatism, 52.6%, was the most frequently encountered refractive error among the participants; followed by myopia, 26.9%; and hypermetropia 2.6%.

CONCLUSION

The current study confirms that refractive error is an important preventable cause of visual impairment. Significant portion of the examined participants were found to have refractive errors recommending further work to improve visual status in undergraduate students.

Association between greater residential greenness and decreased risk of preschool myopia and astigmatism

OBJECTIVE

Rapid urbanization has led to reduced greenness in many areas, this has been linked to adverse health outcomes. The aim was to determine the association between residential greenness experienced during very early childhood with preschool myopia and astigmatism and to explore the potential mediating role of screen time on any associations.

METHOD

Information regarding socio-demographic characteristics, home address, screen time during early childhood, and refraction data from vision screenings of 53,575 preschoolers from Longhua Child Cohort Study were collected via questionnaires. Residential greenness was calculated as the average of satellite-derived Normalized Difference Vegetation Index in buffers of 100, 250, and 500 m around each child's home address. Logistic and linear regression models were used to examine the relationships between residential greenness, screen time, and preschool myopia and astigmatism.

RESULT

The mean (SD) age of the 53,575 preschoolers was 5.0 (0.7) years, and 24,849 (46.4%) were girls. A total of 1236 (2.3%) preschoolers had myopia and 5347 (10.0%) had astigmatism. In the adjusted model, a higher neighborhood greenness level within 100 m buffers around the home address was associated with decreased risk of myopia (adjusted odds ratios (AOR): 0.62, 95% confidence interval (CI): 0.38-0.99), and higher neighborhood greenness levels within 100, 250, and 500 m decreased the risk of astigmatism, and their AORs (95% CIs) were 0.55 (0.43-0.70) for 100 m, 0.59 (0.41-0.83) for 250 m, 0.61 (0.42-0.90) for 500 m, respectively. Greater screen time during early childhood increased the risk of myopia (AOR = 1.33) and astigmatism (AOR = 1.23). Reduction in screen time fully mediated the benefits of greater residential greenness on preschool myopia, but partially mediated that on preschool astigmatism (p < 0.05).

CONCLUSION

Higher residential greenness reduces the risk of preschool myopia and astigmatism; the benefits of residential greenness were mediated through reduced daily screen time.

Analysis of Tear Ferning Patterns in Young Female Subjects with Refractive Errors

To evaluate the dry eye symptoms and ocular tear film in young female subjects with refractive errors (RE) using the ocular surface disease index (OSDI), phenol red thread (PRT) and tear ferning (TF) tests. Methods. A group of 50 young female subjects (mean ± standard division = 20.3 ± 1.1 years) with RE (−0.25 to −6.00D) completed the study. An age-matched control group consisting of 50 healthy normal eye female subjects (22.2 ± 1.5 years) was recruited for comparison. The OSDI was completed first, followed by PRT and TF tests. Results. Median OSDI and TF scores were significantly higher (Mann–Whitney test; P < 0.001) among the study group subjects [median (interquartile range (IQR)) = 13.5 (15.3) and 1.6 (1.3), respectively] compared to the control group [6.0 (4.0) and 0.9 (0.8), respectively], whereas the median PRT score was significantly lower (Mann–Whitney test; P=0.003) in the study group [(27.5 (6.3) mm] compared to the control group [29.5 (5.0) mm]. For subjects within the mild RE group (N = 30), significant differences (Mann–Whitney test, P < 0.001 to 0.005) were found between the median OSDI, PRT, and TF scores and those recorded within the control group. For the subjects with moderate RE (N = 20), significant differences (Mann–Whitney test, P < 0.001 to 0.002) were found between the median OSDI and TF scores, and those recorded within the control group. Conclusion. The presence of RE in young females has a negative effect on tear film in terms of dry eye symptoms, tear volume, and TF grades. Dry eye symptoms experienced by subjects with RE and the TF grades were significantly higher compared with the control group. In addition, the tear volume was significantly lower in the study group. Clearly, RE has a risk factor for dry eye.

The prevalence of refractive errors among Saudi adults in Riyadh, Saudi Arabia

PURPOSE:

To determine the prevalence of refractive errors among Saudi adults in Riyadh, Saudi Arabia.

METHODS:

A cross-sectional study was conducted targeting healthy Saudi adults (20–40 years old) at two major gatherings in Riyadh, Saudi Arabia from December 2018 to January 2019. Refractive errors were measured, and data pertaining to age, sex, region of origin, and spectacle use was collected. Clinically significant myopia was defined as SE ≥ -0.50 D, hyperopia as SE ≥ 0.50D, and astigmatism as cylindrical error ≥ 0.50D. Refractive error measurements were assessed using Topcon's Auto-Kerato-Refractometer, KR-800.

RESULTS:

A total of 660 adult individuals (1,319 eyes) were included in this study, of which 321 participants (48.7%) were found to be myopes, 167 subjects (25.2%) were hyperopes, and 438 individuals (66.3%) had astigmatism. With regards to correlations, myopia was highly correlated with being male (P-value = 0.036), belonging to age group 20–25 years (P-value = 0.033), originating from the northern regions of Saudi Arabia (P-value <0.001). Similarly, hyperopia was significantly correlated with being male (P-value = 0.048), age groups 20–25 years (P-value = 0.04), and 31–35 years (P-value = 0.011) and was higher in people from northern region (P-value = 0.011). In contrast, astigmatism was only found to be correlated with age group 36–40 years (P-value = 0.002). Additionally, 71.7% of myopic participants and 76.1% of astigmatic individuals opted not to wear spectacles (P-value <0.001).

CONCLUSION:

In this study, the refractive error with the highest prevalence among Saudis was astigmatism, followed by myopia and hyperopia. Gender, region of origin, and spectacle wear were all observed to be highly correlated with higher rates of refractive error.

Prevalence of Refractive Errors and its Associated Risk Factors among Medical Students of Jazan University, Saudi Arabia: A Cross-sectional Study

PURPOSE

Refractive errors (REs) are common and continue to increase globally, particularly myopia. Uncorrected REs are the second leading cause of preventable blindness and the most common cause of visual impairment. The main objective of this study is to assess the prevalence of REs and to investigate its associated risk factors among medical students of the Jazan region, Saudi Arabia.

METHODS

An observational analytical cross-sectional study was conducted among a random sample of 447 medical students at Jazan University. Eye examination was conducted using an autorefractor test (Huvitz HRK-8000A Autorefractor Keratometer) to measure spherical refraction (emmetropia, myopia, and hyperopia) and cylindrical refraction (astigmatism). Factors associated with myopia and hyperopia were evaluated using logistic regression models.

RESULTS

The overall prevalence of REs was 48.8% (95% confidence interval [CI] [44.2, 53.4]). The prevalence of REs among female medical students was 55.1% (95% CI [48.6, 61.5]), which was significantly higher than that among males (42.3%, 95% CI [36.0, 48.9]), with a P = 0.007. Of the 447 medical students examined, approximately one-third (33.8%) had myopia, 10.5% had astigmatism, and only 10.5% had hyperopia. The results of logistic regression indicated that females were 52% more myopic than males (odds ratios [OR] = 1.52, 95% CI [1.04, 2.22]), while participants with both parents having a history of REs were twofold more myopic than students with no family history of REs (OR = 2.01, 95% CI [1.2, 3.4]). A history of blurred vision also increases the risk of myopia by seven times (OR = 7.2, 95% CI [6.4, 11.3]).

CONCLUSION

RE among medical students is a problem. Thus, it needs to be assessed carefully before students choose a specialty that may need very good near and far vision for postgraduate study.

The prevalence of refractive errors in the Middle East: a systematic review and meta-analysis

PURPOSE

The purpose of the present study was to evaluate the prevalence of refractive errors in the Middle East region.

METHODS

In this meta-analysis, a structured strategy was applied to search databases PubMed, Web of Science, Scopus, and Google Scholar, databases as well as the reference lists of the selected articles to identify cross-sectional studies assessing the prevalence of refractive errors in the Middle East region until September 2019. The outcome measure was the prevalence of refractive errors, including myopia, hyperopia, and astigmatism, in two age groups of ≤ 15 years and > 15 years. The study results were combined using a random effects model at a confidence level of 95%.

RESULTS

The prevalence of myopia, hyperopia, and astigmatism was 4% (95% CI 4, 5), 8% (95% CI 6, 10), and 15% (95% CI 10, 19) in people less than or equal to 15 years and 30% (95% CI 25, 34), 21% (95% CI 15, 28), and 24% (95% CI 16, 31) in subjects over 15 years, respectively. The prevalence of myopia, hyperopia, and astigmatism was 3.5%, 12.4%, and 9.0% in male and 4.2%, 13.1%, and 9.9% in female subjects aged ≤ 15 years, respectively. In subjects aged > 15 years, the prevalence was 31.7%, 14.5%, and 31.5% in males and 31.9%, 11.2%, and 31% in females, respectively.

CONCLUSION

The prevalence of hyperopia is relatively high in Middle Eastern children, while the prevalence of myopia is higher in adults in this region. It seems that astigmatism is not a serious refractive problem in this region compared to the rest of the world.