Introduction

A human’s most highly developed sense is sight [1]. Therefore, people probably rely more on vision than all other senses combined [2]. Vision is a critical tool used to engage in everyday activities, attain self-gratification, perceive beauty, mobility, learn, utilize tools, and enjoy every aspect of life [1]. Predictably, a cross-sectional study conducted in the United Kingdom showed that the most valued human sense is sight [3]. Consequently, vision loss has a significant negative impact on everyday activities, depressive symptoms, and feelings of anxiety [4]. Moreso, individuals with vision loss commonly have depression [5] and post-traumatic stress disorder [6]. Additionally, a cross-sectional study showed that people with loss of vision had 4.6 times significantly greater risk of experiencing psychological distress than people with normal sight [7]. Critically, findings from a more recent comparative cross-sectional study, showed that psychological distress was significantly more prevalent in visually impaired adults than adults with normal vision [8]. More importantly, depression is linked to poorer outcomes in vision rehabilitation [9]. Even foreseeable vision loss can cause severe psychological suffering that could result in suicide [10]. Conclusions from a systematic review showed that vision loss usually impacts negatively on the quality of life as well as the mental health [11].

Vision loss, also called visual impairment, can be congenital (present at birth or before the age of 5) or adventitious (acquired at or above the age of 5) [12, 13]. According to Bruce [12], the impact of visual impairment on people, depends on the age at onset. Findings from a cross-sectional study showed significantly greater levels of depression in students with adventitious visual impairment compared to those with congenital visual impairment [14]. Moreso, the people with adventitious visual impairment have poorer quality of life and find it more difficult to deal with vision loss than those with congenital visual impairment [15]. Considering the evidence that the mental health of people with adventitious visual impairment is disproportionately impacted compared to that of those with congenital visual impairment, the focus of this scoping review is adventitious visual impairment which encompasses both total bilateral blindness and low vision [15].

Considering the mental health problems encountered by people with adventitious vision loss, prioritizing their mental health becomes critical. However, to optimally achieve prioritization, it is imperative that factors impacting on their mental health are comprehensively explored and understood. Hence, this scoping review will explore the protective and risk factors of mental health of people with adventitious visual impairment. Protective and risk factors are defined as the diverse and usually complex factors impacting on mental health and well-being [16]. On one hand, protective factors are those factors which strengthen the mental health of an individual and operate in ways that will improve the ability of an individual to cope with problematic situations [16]. On the other hand, risk factors have adverse impact on the mental health of an individual [16]. Essentially, protective and risk factors aid in explaining the reason for the form and nature, distribution, and persistence of a problem [17]. To achieve and sustain positive mental health, protective factors need to be developed, risk factors minimized and barriers to seeking help, removed [16].

It is, however, imperative for the authors to elucidate the meaning of protective and risk factors for mental health within the context of this scoping review. Critical findings from studies have established that certain factors positively or negatively impact on mental health. These factors will be considered as protective or risk factors of mental health respectively in this scoping review. For instance, multidisciplinary rehabilitation (including visual rehabilitation) [18–20] and physical activity [21] improve mental health of adults and therefore will be considered as protective factors.

Conversely, vision-specific distress which refers to the type of distress associated with coping with visual impairment has been found to be a critical risk factor for depressive symptoms [22]. In two cross-sectional studies involving visually impaired adults, vision-specific distress compared to other variables like social support and coping, was found to have the most unique and strongest association with depression [22, 23]. Although higher levels of general coping tendencies as adaptive mechanisms have been associated with lowered depressive symptoms in people with visual impairment [24], avoidance coping however, is significantly associated with depressive symptoms making it a risk factor for mental health problems [22, 25].

Additionally, a life of chronic disability frequently consists of dependence on friends and family for assistance with emotional support and instrumental tasks [26]. Such social support has been acknowledged by researchers as having potential to positively affect the lives of persons with chronic disability [26]. It has however been acknowledged in recent times, that there are negative aspects of social support like being angry and hostile which are capable of adversely impacting the lives of people with chronic disability [26, 27]. Hence, social support can comprise of positive and negative aspects that exist concurrently in a person’s environment [26]. According to Antonucci, Lansford and Akiyama [27], close friends and significant others can be sources of affection and love as well as antagonism and distress. In their research, positive and negative facets of social support impacted on well-being of the study participants differently. For instance, depressive symptomatology was significantly correlated with significant others, getting on one’s nerves (negative social support) while life satisfaction was significantly associated with confiding in spouse (positive social support) [27]. Moreover, the findings from a systematic review showed that spousal support as a source of social support was the most consistent significant protective factor against depression for adults [28]. In this present scoping review therefore, positive social support will be considered a protective factor of mental health while negative social support will be taken as a risk factor for mental health problems.

Furthermore, research has identified stigmatization as detrimental to mental health. According to Thornicroft et al [29], stigma is a symbol of discredit which evokes negative attitudes directed towards the stigmatized. It is an all-encompassing term which consists of discriminatory acts, lack of knowledge and prejudice [29]. They argue that negative thoughts are not the only acts of prejudice that the majority exhibit in the rejection of the minority, but they can also be hostile, resentful, anxious, angry, and repulsed [29]. Critically, Link and Phelan [30] assert that individuals are considered stigmatized when they lose status and are discriminated against because of being labelled, separated, and associated with repugnant attributes. Generally, stigmatized groups are at a disadvantage in terms of life chances such as mental health, earnings, education, health, accommodation, status, and medical care [30]. According to Williamson [31], social stigma can aggravate depression as well as development of self-stigmatization which is conceptualized as having negative belief about oneself (stereotype), agreeing with said belief (prejudice) and responding to prejudice (discrimination) [32]. In a study conducted by Van Munster et al [33], participants believed that their mental health issues were exacerbated when they felt vulnerable and unequal because of their visual impairment. Many people with visual impairment face self-stigma with regards to the visual impairment as well as mental health issues which can aggravate these problems [33]. Therefore, stigmatization is considered a risk factor for mental health problems.

According to the World Health Organization (WHO), people with disabilities are twice as likely to develop depression [34]. The WHO asserts that such inequalities stem from social situations encountered by people with disabilities such as stigmatization, being excluded from employment and education, discrimination, and poverty [34]. Predictably, individuals with visual impairment, a lot of whom have low socioeconomic status, face an array of challenges in being able to access sufficient healthcare which can worsen the state of their mental health [35]. Therefore, socioeconomic status (SES) is consistently and reliably predictive of mental health [36].

These examples are by no means exhaustive. A wide range of factors exist and will be explored by this scoping review.

Importantly, exploring protective and risk factors for mental health problems among working age adults with adventitious total bilateral blindness and low vision will be critical in the promotion of mental health literacy for service users and providers. According to O’Connor, Casey and Clough [37] and Jorm et al [38], knowledge of factors associated with mental health problems is a major attribute of mental health literacy. Moreso, while the significance of health literacy for physical health is broadly recognized, the field of mental health literacy is comparatively neglected [39, 40]. Given that this review will explore and chart factors impacting on mental health problems, it will boost knowledge and create awareness of these determinants thereby promoting mental health literacy for service users and providers.

Scoping reviews are appropriate for mapping relevant evidence on a specific subject matter or field of research and support for the identification of fundamental concepts, research gaps and sources and kinds of evidence for informing research, practice and making of policies [41]. Given that scoping reviews are conducted for varied reasons, it is imperative to clearly explain the purpose for which this scoping review is being conducted [42]. According to Peters et al [43], scoping reviews are used to assess and understand the scope of the evidence in an emerging area or for the identification, charting, reporting or discussion of the features/concepts in that area. Hence, they are inherently exploratory [44]. A scoping review was therefore, considered to be the most appropriate type of review to meet the objectives of the proposed research. This is because, it will allow the researchers to explore, identify, chart, and report available evidence on potential factors to promote positive mental health (protective factors) and factors that might be detrimental to positive mental health (risk factors) of working age adults with adventitious total bilateral blindness and low vision.

Importantly, Møller [45 p. 32] asserts that a way of “mapping” the evidence to unravel what is known and not known is to conduct systematic reviews. It has been established that mapping, as a term, is frequently utilized when explaining a process of evidence analysis [46]. However, Khalil et al [46] argue that it may be the case that the meaning of mapping and how it is attained may be misconstrued. They clarify that mapping can be used to ascertain the scope of a scale of evidence in a specific area [46]. The “mapping” in our scoping review aligns with Khalil et al’s [46] clarification which is to scope the extent of available evidence on protective and/or risk factors of mental health for our target population.

The conduct of our scoping review will be underpinned by methodological rigor and transparency throughout. In addition, dissemination of research findings and informing future research (for instance systematic reviews, primary research, and other forms) are among the core expectations and outputs of properly conducted scoping reviews [47]. Hence, this scoping review will be pivotal in making contributions to empirical research and appropriate recommendations which will be underpinned by the review’s findings.

A preliminary search of Prospero (22^nd March 2023), Cochrane Database of Systematic Reviews (22^nd March 2023) and JBI Evidence Synthesis (26^th March 2023) did not identify any published or ongoing review (scoping or systematic) on this topic. Some reviews like Senra et al [11] have studied the impact of adventitious vision loss on mental health, however, the focus of our review will go beyond that to explore the determinants that can maintain the integrity of the mental health as well as those that can deteriorate mental health in our study population. Moreover, Senra et al’s [11] review was conducted almost a decade ago with no major advances in the field, further justifying the critical need for this scoping review. Hence, conducting this scoping review is timely and of critical importance as it will fill the gap in literature.

Methods

This proposed scoping review will be carried out in accordance with the latest Joanna Briggs Institute (JBI) methodology for scoping reviews [42, 48] and the PRISMA-ScR reporting guidelines (see S3 Appendix), both of which underscore the significance of methodological rigor [49]. Also, evidence and knowledge gaps will be identified, and appropriate recommendations for service provision made.

Discussion

The intended scoping review aims to map the available evidence on the protective and risk factors of mental health problems of working age adults with adventitious total bilateral blindness and low vision. Additionally, the proposed review intends to report gaps in the evidence base in relation to the mental health of this target population. Moreso, to the best of the researchers’ knowledge, no review to date has explored protective and risk factors of mental health of this target population. Hence, the review will add and enrich the evidence base on the determinants of mental health of this target population. The findings from this scoping review will inform the design of interventions for the study population and for the promotion of mental health literacy. Also, this review will: inform and underpin future research on the mental health of this study population; and be of assistance to rehabilitation specialists and workers, health promotion practitioners and other relevant stakeholders in tackling the mental health needs of working age adults with adventitious total bilateral blindness and low vision.

This scoping review’s limitation is that it will exclude studies that are not written in English language.

Supporting information

Acknowledgments

Ochea Ikpa: Ensured that the corresponding author dotted every “I” and crossed every “T”.

Melanie Bickerton: The authors collaborated with her in the development and refinement of the search strategy at the protocol stage.

Dr. Oghenebrume Wariri: The corresponding author received invaluable professional guidance from him throughout the development of the review protocol.

Clare Robertson: The corresponding author received expert guidance from her during the development of the review protocol.

Professor Amudha Poobalan: The corresponding author was expertly guided by her in the development of the search strategy for this review protocol.