Primary Health Care: Open Access

The importance of the Optometrist's role as a primary health care provider in the Sultanate of Oman

owsen Ol Balushi^{* *}Correspondence: owsen Ol Balushi, Therapeutic Optometrist, University, Oman, Email:

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Introduction

The essential part of our body is the eye [1]. It gives us a vision which is the dominating of our senses [1]. Vision is an essential sense for our existence to function and nurture the earth [1]. Devolvement of vision since childbirth is very crucial because it will help build their cognition, coordination, balance, and their social development [1]. Furthermore, Vision aids adult engagement in the workforce, resulting in self-identity appreciation and economic benefits [1]. Vision impairment is a vision deficiency with total vision correction [2]. It negatively affects an individual’s performance [2]. At a minimum, 2.2 billion people globally are visually impaired with at least 1 billion suffer from preventable vision loss that is greatly observed in developing countries [1]. However, individuals who receive prompt diagnosis and treatment may not suffer from vision impairment because numerous eye disorders that cause blindness can be prevented if diagnosed and managed early [1]. In addition, some eye conditions do not lead to vision impairment, but they do so if they are left untreated like eye infections [1]. The knowledge of common eye disorders and their early detection will help to encourage people to pursue prompt eye care and thereby reduce the burden of vision loss [3]. Approximately 75% of blindness, as reported by International Agency for the Prevention of Blindness (IAPB), is preventable [3]. It has been predicted that 703 million people may have vision impairment by 2050 [4]. Despite the developments in the medical field, the vision impairment problem is still growing as the population is growing and getting older since more vision impairment amongst older people due to diabetic retinopathy, glaucoma, and cataracts4 . In addition, people who are visually impaired by uncorrected distance vision or presbyopia are 1.1 billion in 2020 and this number is expected to increase to 1.8 billion by 2050 [5]. In the United States, blindness is highly associated with age regardless of gender or ethnicity [6]. 3.3 million Americans aged 40year and above have vision impairment in which half of them suffer from cataracts [6]. In the Sultanate of Oman, there are 210 thousand individuals aged 60+ years old in 2020 [7]. It has been anticipated that the old population’s proportion in Oman will rise from 4.4% in 2030 to over 22% in 2065 [7] which means a higher proportion of eye conditions that need a prompt and effective eye health care to prevent vision impairment. World Health Organisation (WHO) stated that the yearly expense of productivity loss globally due to untreated myopia and presbyopia is US$244 Billion and US$25.4 billion, consecutively [8]. The concept of optometry as stated by the World Council of Optometry is “Optometry is a healthcare profession that is autonomous, educated, and regulated (licensed/registered), and optometrists are the primary healthcare practitioners of the eye and visual system who provide comprehensive eye and vision care, which includes refraction and dispensing, detection/diagnosis and management of disease in the eye, and the rehabilitation of conditions of the visual system” [9]. In 1971, optometrists start using pharmaceutical agents to diagnose eye conditions [10]. In 1976, optometrists are allowed to use pharmaceutical agents for treating eye conditions [10]. The optometry profession has advanced and the scope of practice has expanded through the years and now they are graduated with a doctor of optometry and called doctors in many countries similar to the other health professionals such as dentists and veterinarian [11]. Furthermore, Saudi Arabia is the only Gulf country where provides a Doctor of Optometry degree and the optometrists are considered primary health care providers [12].

Optometry is an independent eye health care profession that extended hundreds of years ago [13, 14]. It is not a new profession that developed in recent years as this is misconception [13, 14]. Optometrists are extensively spread in communities throughout the world, and their services are economically valuable and available for all people [15]. By the primary eye care that is provided by optometrists, children are prepared better for a more successful, productive, and independent life [15]. Four categories are describing the optometristâ??s scope of practise [16]. Category 1 is optical technology services which are managing and dispensing ophthalmic lens and frame [16]. Category 2 is visual function services [16]. It is category 1 plus exam, recognize, and correct refractive error16. Category 3 is ocular diagnostic services [16]. It is category 1 and 2 plus examines the eye health anteriorly and posteriorly, diagnose and manage eye diseases [16]. Category 4 is ocular therapeutic services [16]. It is category 1, 2, and 3 plus using pharmaceutical agents to diagnose and treat eye conditions [16]. The new generation of Omani optometrists is from categories 3 and 4. The majority of them graduated from the University of Buraimi with a bachelor of science in optometry and they are qualified to practice optometry category 3. Few of them graduated from New Zealand, UK, and USA who are qualified to practice optometry in category 4. The purpose of this questionnaire, therefore, is to determine the cruciality of optometrist engagement in eye care delivery through analysing the level of awareness of eye diseases and the accessibility to eye health care providers among Omani citizens and residents within various Omani governate.

Methodology

This anonymous questionnaire survey was conducted in February 2021 by Omani Optometry Club (OOC) using the “QuestionPro” website in the Arabic language. The target group of this survey is individuals from various eleven Omani governates including AlBuraimi, Al Dhahira, Al Dakhlia, Al Batinah North, Al Batinah South, Al Wasta, Al Sharqia North, Al Sharqia South, Musandam, Muscat, and Dhofar, with diverse age groups that are divided into four groups (10 years to 20 years, 21 yers to 40 years, 40 years to 60 years and +60 years). The questionnaire was randomly distributed on social media apps mostly in Instagram, WhatsApp, and Twitter. The survey was created on 12th February 2021. The initial publication of the survey was on 13th February 2021. It was published again after 10 days to remind people who have not been surveyed for the first time. Then, it was published one more time after 20days. In total, the survey was open for one month and a half and was closed in April 2021. The questionnaire conducted in this survey is available at https://www.questionpro.com/qp_userimages/ sub3/4107422/QuestionPro-Survey-8159391-PDF-Export-09-082021-T052008.pdf.

The questionnaire was formulated into twelve multiple-choice questions, one multiple-select question, and four open-ended questions. The survey started with personal details like gender, age group, and which governate the participants from. Then, there were questions about the awareness of participants and their relatives about their eye health. The last two questions were about the participants’ reviews about their nearest eye care service. To maximize the number of respondents, the survey was published multiple times. The setting of the questionnaire allowed the participants to return to previously completed sections in the survey and revise their responses to avoid missing questions or wrong answers. Moreover, respondents may exit the survey at any moment, yet all the answers were saved automatically. This survey was designed to be completed in 4-5minutes. The responses of the survey from the QuestionPro have been exported to an excel spreadsheet for data analysis.

Results and Discussion

In our survey, there were a total of 1815 views of which 903 participants attended the survey. 235 participants opened the survey but didn’t complete it. Only 668 participants completed the questionnaire, representing a completion rate of almost 74%. A total of 660 (73.74%) female and 235 (26.26%) male participants completed the survey from a variety of socioeconomic backgrounds; both urban and rural (Table 1). The majority of participants were from the 20-40 age groups and located in the Al Batinah North (Figure 1).

Table 1. Demographic characteristics of the study population.

Figure 1: The proportion of participants from each governate.

After the demographic questions, questions had been asked to indicate the level of eye health and care awareness that participants have. According to our study, 76% of individuals have done at least one eye test in their life, in which 23% do routine eye examination every 1-2years, whereases about 77% of them do the eye examination when they have eye problems only. On the other hand, 24% of participants have never done an eye test in their whole life which is a major percentage (Table 2).

Table 2. Awareness of the study population about eye health and care.

Among the study population, approximately 44% of the participants have an eye problem; about 57% of participants’ relatives suffer from an eye condition. In addition, 12% of participants have children with an eye abnormality whose age group varies from 2weeks to 20years old. The other 88% of participants said No, they either do not have children with an eye problem or they do not have any children (Table 2). Further, there was a question has been asked “what do you do when you have an eye problem?” As mentioned in the survey, 73% of participants prefer to go to a hospital/ clinic for any eye problem. Only 10% of them visit the closest optical shops for an eye examination (Table 2). This explains that Omani society is unfamiliar with the idea that there is a primary care optometrist who can diagnose and manage many ocular conditions, are located in the optical shops. Worthy to mention, 12% of participants do nothing when they have an eye problem (Table 2). This may demonstrate the lack of knowledge that some participants have about the importance of eye examination and the cruciality of detecting any eye abnormalities in the early stages.

In addition, participants have been asked whether they are wearing optical/sunglasses or cosmetic/ prescribed contact lenses, 56% said yes. However, 44% of participants do not wear any optical correction or sunglasses. This may reflect that these individuals may not have an eye problem, may have refractive error but cannot afford to buy the optical correction, or are unaware of the refractive error that they have. Moreover, some participants neglect the benefit of wearing sunglasses for eye protection from sunlight to prevent common eye conditions such as pterygium and cataract.

Additionally, there was a question related to the eye conditions that the participants or their relatives have, and the results are illustrated in Figure 2.

Figure 2: The awareness of study population about their eye conditions.

According to the questionnaire, 25% of participants or their relatives are myopic which is the highest proportion compared to other eye conditions. Myopia (or near-sightedness) is an ocular condition that causes vision blur at a distance while near vision is clear [17]. It is corrected by optical glasses, contact lenses, or refractive laser surgery [17]. Myopia is one of the common ocular conditions worldwide that causes visual impairment in children and affects their school and social life18. Globally, 27% of the population are myopic and 2.8% of them have a high myopia [18]. Uncorrected myopia causes headache and eye strain which leads to reduce production rate in every field [19]. A study was conducted in 2009 by Smith and his colleagues concluded that uncorrected refractive error results in productivity loss [19]. Another study was done in southern China (2006) indicated that uncorrected myopia causing vision disabilities is much higher in school-aged children and it suggested that prompt vision screening for children is crucial to treat this simple and treatable eye condition [20]. In addition, providing myopia control for children is imperative to reduce future myopia complications [21]. The optometrist is trained to do that by using pharmacological, special soft and hard contact lenses, and special spectacle lenses to reduce myopia progression21. Without early detection and intervention of myopia, eye health care professionals concur that a child’s vision and eye health will deteriorate over time [22]. The profession of optometry is necessary for managing and controlling myopia with spectacle and contact lenses [22].

In the present study, the prevalence of hyperopia (longsighted) is 7%. Hyperopia is a refractive error that the distance vision is usually better than near vision [23]. Some studies demonstrated that hyperopia in early childhood may develop strabismus and amblyopia later in life [24]. Other studies concluded that uncorrected hyperopia negatively affects the child’s educational progress in primary school [25]. Astigmatism was found in 7% of our population which is similar to the prevalence of hyperopia. Astigmatism is a refractive error, causing distortion vision at distance and near due to irregular cornea [26]. Keratoconus is a progressive, bilateral eye disorder, characterized by a cone-shaped and thinned cornea that causes distortion vision, glare, and light sensitivity [27]. Usually, keratoconus patients have myopia and irregular astigmatism. It can be managed surgically or non-surgically by optical glasses and contact lenses [27]. Keratoconus is greatly common among Middle Eastern societies including the Sultanate of Oman [28]. This survey signifies that 4% of participants or their relatives have keratoconus. A recent study has done by a group of ophthalmologists in 2015 suggested that the keratoconus is to be managed initially by non-surgical methods including optical correction or hard contact lenses (scleral lenses) as they are noninvasive and give good vision and comfort compared to the surgical methods that have unpredicted results except corneal crosslinking surgery which is crucial to halt or slow the keratoconus progression [29]. Another study (2017) suggested that hard contact lenses should be considered as the first option in vision rehabilitation for keratoconus patients [30]. Besides, they mentioned that optometrists play an outstanding role in early diagnosis and managing keratoconus as they are contact lens specialists [30]. Refractive errors such as short-sighted, longsighted, and astigmatism, affect an enormous proportion of individuals regardless of their gender, age, and ethnic groups [31]. According to estimates, more than 2.3 billion people globally have reduced vision due to refractive error, with 670 million people classified as visually impaired due to lack of access to eye health care services [32]. Furthermore, Uncorrected refractive error has shown to have social and economic consequences in the individuals’ life including educational and job aspects because of less range of job opportunities they may have [31]. Worthy to mention, vision disabled population have less chance to be employed compared to other types of disability. The Royal New Zealand Foundation of the Blind (RNZFB) revealed that 79% of visually impaired participants agreed that they have less opportunity to get and maintain a job and to advance their careers [33]. Uncorrected refractive error is the well-known cause of blindness globally and is the easiest to be treated by optometrists [34]. However, the shortage of optometrists is the main cause of blindness, particularly in developing countries [31]. A study showed that the blindness rate in developing countries is 7 times higher than 1.4% in the developed countries [31]. In addition, some countries do not have access to eye care centres, or they cannot afford to buy the optical correction [31]. A consistent but significant increase in the number of eye care practitioners trained in refraction and vision correction is required to give high-quality eye care to countries with the greatest need34 like Sultanate of Oman. Presbyopia is an aging (mostly +40 years old) and gradual change to the natural ocular lens flexibility resulting in blur vision at near [35]. According to our survey, 5% of our study population has presbyopia. Only 11% of the participants were aged 40 and above, thus, we predicted that the prevalence of presbyopia may be higher. In 2005, it was projected that more than 1 billion people worldwide were affected by presbyopia, more than half of them are unable to obtain the requisite refractive correction to remedy the near vision reduction [36]. Resulting in a possible loss of productivity which is significant in low-income countries in comparison to rich countries [37]. Strabismus (or crossed eyes) is depicted as misalignment of the eyes, if left untreated, binocularity and depth perception may be lost [38]. As stated in our survey, 2% of participants have strabismus. Cataracts is an eye disorder, describes as clouding of the clear lens in the eye that causes blur vision, light sensitivity, and change of colour perception [39]. As reported by our questionnaire, 10% of our population suffer from cataracts. Cataract is the leading cause of blindness globally whereabouts 20million people are blind due to this eye condition specifically in developing countries [40]. The only cataract treatment is surgery [40]. Optometry, hopefully in collaboration with ophthalmic surgeons, can play a significant role in diagnosing, correcting vision, and educating cataract patients [40]. Besides, primary eye care optometrists examine patients for years, once the patient is diagnosed with cataract, they monitor the case, and once the vision is no longer improving with the glasses, they educate and refer cataract patients to an ophthalmic surgeon, along with, they have the skills to perform pre-operation assessment and postoperative care [41]. Amblyopia (or lazy eye) is defined as a reduction in vision permanently in one eye or both eyes that cannot be corrected by spectacles, contact lenses, or surgeries and are not associated with ocular pathology [42]. It occurs as a result of abnormal vision development during early childhood [42]. The treatment of amblyopia is critical to be established at the early childhood age before the age of 8 or 10 as it cannot be intervened after that [42]. Nearly 3% of our survey’s population suffer from amblyopia. The amblyogenic risk factors are uncorrected refractive error, strabismus, and ocular deprivation which is the least common and most severe cause of amblyopia that may be caused by cataract, ptosis (drooping lid), or corneal lesions [42]. To avoid permanent vision loss, early detection and referral by an optometrist are critical, particularly during childhood [42]. A study done among primary school children in Tahran revealed that the percentage of amblyopic patients with hyperopia and anisometropia (different refraction between the eyes) are higher compared to other amblyogenic factor [43]. Moreover, they pointed out the essentiality of using prompt and sensitive screening test procedures for detecting and monitoring amblyopia [43]. It concluded that the ministry of health should pay special attention to the availability of primary eye care providers and the accessibility of refractive correction devices since the higher rate of amblyopia are due to uncorrected refractive error43. As there are eye conditions that cause irreversible blindness, there are other eye condition that are benign and does not cause significant vision loss, but they cause discomfort or sore eyes, such as dry eye, conjunctivitis, and other simple eye infections [1]. Approximately 12% of our study population endure eye infection/ allergies and 13% suffer from dry eye. If the primary health care providers diagnose and manage these simple cases early, it will result in quick recovery, happy and more productive individuals [1]. Among our study population, the prevalence of retinal problems is 7%. Diabetic retinopathy is one of the retinal conditions that lead to blindness and affect productivity, particularly among old adults [44]. The diabetic retinopathy complication is a consequence of the low rate of retinal screening, perhaps due to the non-availability of the primary eye health care professional to provide retinal screening services or the unawareness of the priority of retinal screening among diabetic patients [44]. According to a DRIVE UK study, 52% of Africans have diabetic retinopathy compared to 38% of white European [45]. This suggested that Africans are more likely to be visually impaired due to diabetic retinopathy in comparison to white European45. In the Sultanate of Oman, there is a proportion of African ethnicity, particularly from Zanzibar [46]. Glaucoma is a progressive eye disorder affecting the optic nerve and it is the leading cause of irreversible blindness worldwide [47]. 4% of our study population have known to have glaucoma. Detecting glaucoma early is vital as it is asymptomatic at early stages [47]. The optometrist’s role in detecting and diagnosing glaucoma is very important as they are doing comprehensive eye tests that include checking the health of the optic nerve and checking the eye pressure [48]. Also, they are trained to perform and interpret many diagnostic glaucoma tests like Optical Coherence Tomography (OCT) and visual field, for diagnosing glaucoma, monitoring progression, and referral to the glaucoma specialized ophthalmologist for therapeutic and surgical treatment [48]. Further, there was a study done between 1990-1999 of 87 participants whose average age is 78years old [49]. All of them were referred to the hospital for glaucoma, in which half of them already have symptoms of visual field reduction and 45% of them have never seen an optometrist in their life [49]. One-third of patients registered that time of referral as blind which should have been registered early [49]. Later, 95% of these patients are managed by optometrists for rehabilitation services to aid using their remaining vision [49]. This study confirmed the importance of an optometrist as a primary health care provider in diagnosing, managing eye conditions, and does a timely referral. Furthermore, another research was conducted about the accuracy of eye condition referral from general practitioners and optometrists [50]. It revealed that patients with suspected glaucoma were considerably more likely to be accurately referred by optometrists than by general practitioners [50]. In addition, optometrists were found to be more precise in diagnosing diabetes by ocular screening, and they are more likely to refer asymptomatic diabetic retinopathy cases for photocoagulation compared to zero referral from general practitioners [50]. Therefore, regular comprehensive eye examination by optometrists will reduce the number of unnecessary consultation appointments with ophthalmologists and will increase the referral for effective therapy when needed [50]. Among the study population, relatively, 31% of participants’ relatives suffer from low vision (Table 2). Low vision is a vision loss, caused by eye conditions that cannot be treated with optical correction or surgeries [51]. It causes disability and reduces the functionality of an individual [51]. The most common causes of low vision are amblyopia, glaucoma, cataract, and diabetic retinopathy [51]. The causes differ significantly between and within nations, depending on the availability of eye care services, their economical state, and the population's eye care knowledge. Therefore, if the above diseases are diagnosed and treated early, the prevalence of low vision patients will be less [51]. The management of low vision is vision rehabilitation which is one of the optometrist’s specialty areas. It helps low-vision patients attain their visual goals and improve their quality of life by maximizing their visual functionality [52]. Low vision has a huge impact personally as it will affect the individual’s quality of life, education, and employment [52]. Additionally, it is a financial burden on the country [52]. At the end of the survey, there was a question related to the quality of eye health services in the participant’s town. Around 24% of participants agreed that the health service quality in their town is excellent, 59% of participants conceded that the quality of eye health service is good, and 16% of participants agreed that the quality of eye health service is substandard (Table 2).

For maximizing the quality of eye health services in Oman, some participants recommended:

Increasing the awareness of common eye conditions and the importance of conducting routine eye examinations among Omani citizens particularly 40+ years old individuals. The Optometry in Oman Sawsan Al Balushi (BOptom (Hons, TPA Additionally, bringing attention to the Omani society about the importance of seeking medical advice when having an eye problem.

Establishing a fully equipped optometry clinic in every hospital/ polyclinic and supporting the Omani optometrists to open their optometry centres (optical shops) in every town as a primary eye health care provider. The advantage of this is to reduce the waiting time for an eye appointment in the government hospital, thus reducing the later complication due to late intervention.

Employing 2-3 optometrists to one ophthalmologist (like 2:1 ratio) in the government hospital and private eye centres. Therefore, every patient will get the chance to receive a comprehensive eye examination especially if he was a new patient to the facility. By doing this, optometrists may diagnose asymptomatic eye conditions such as glaucoma and intervene early.

Monitoring the optometry clinics and the optometry centres (optical shops) by qualified optometrists to catch the opposing places that do not meet the optometry clinic standard, or they sell harmful products like fake contact lenses for example.

Performing compulsory before-school-check for children by qualified optometrists.

Establishing fully equipped vision rehabilitation centres for low vision patients.

Supporting individuals with limited income in buying the optical correction or performing urgent surgeries.

There are four strategies proposed by the world health organization to maximize eye health care in the community [53]. Firstly, increase the consciousness of the vitality of detecting and managing eye conditions at early stages, as well as, knowing how to access the eye care services conveniently [53]. Secondly, reinforce primary eye care. Primary health care provider (optometrist) can diagnose and manage eye conditions, along with, referring moderate to complicated cases to tertiary eye health care (ophthalmologist) [53]. By accessing these services, the vision impairment can be prevented or slowed down in some cases [53]. Furthermore, these primary eye health care services that are provided by an optometrist are cost-effective, have low household spending, and are closer to the community as they are easy to access [53]. Thirdly, coordination between eye health care services and other services or programs like education, diabetes, and child health for maximising eye health care in the community. Finally, establishing an enabling health environment by providing trained eye care providers who appreciate the thorough eye care for assessing individuals’ needs, planning effective service delivery, and monitoring [53].

There are millions of individuals who are blind or visually impaired because simply they do not have access to eye health care or cannot afford to buy optical correction to correct their vision. Additionally, the likelihood of eye diseases progressing, and treatment outcomes are both influenced by access to high-quality eye care. Despite the growth of ophthalmologists’ numbers globally, yet there is no full coverage for eye care delivery [54]. In the past, some ophthalmologists perform refraction in developing countries which has been changed in the recent decades to improve eye health care to cover patient’s needs[54]. To perform comprehensive eye care that accommodates an individual’s need, a complete eye care team should be presented including ophthalmologists, optometrists, and other ophthalmic professional [54]. Additionally, concentrating on the proper distribution of the eye care personnel and building a comprehensive eye care delivery system will cover the population’s demand [54].

World council of Optometry assumes that the optometrist job should NOT be refraction only [55]. Optometrist needs to do a comprehensive eye examination including refraction and examining the eye health anteriorly and posteriorly to detect any eye abnormalities such as cataract, glaucoma, or even systemic diseases such as diabetes and hypertension [55]. The proportion of the irreversible blindness that is caused by these eye conditions will be much less as long as they are detected in the early stages [55]. Worthy to note, the necessity of correcting the refractive error is an opportunity for the optometrist to get access to screen for more significant eye conditions like glaucoma and cataract and make the appropriate referral to tertiary eye health care provider for further investigation and early management of the disease. The critical aspect of having a practical, comprehensive, cost-effective eye care system is understanding that it is inexplicable to bring half of the population who, demand refractive care, into a hospital setting [31]. What is reasonable is that optometrists who provide primary eye screening, handling immediate and easy intervention, and refer for complicated cases which basically define the classic eye health care delivery [31]. Each and every one has the complete right to have a good sight. Any child should not struggle with learning in school due to uncorrected refractive error, amblyopia, or undetected eye condition. Moreover, any elderly person should not struggle in reading and managing their jobs because they cannot read or suffer from irreversible blindness from a condition that can be managed and treated if diagnosed early. One of our tragic crises globally is preventable blindness. Optometry is a fundamental part to erase this tragedy by recognizing the cruciality of providing effective and continuous eye health care to individuals who are in need universally.

Conclusion

Vision and eye health is too crucial to take unnecessary risks. Primary eye care optometrist is an elemental member of the eye care team and a key component of a successful eye care delivery system.

Acknowledgment

This survey was supported by Omani Optometry Club [OOC- a member of the Eastern Mediterranean Council of Optometry (EMCO)]. Many thanks for their help in distributing the survey all over the Omani communities.

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