Living with Visual Impairment and Methods to Support Healthy Behaviors in People with Visual Impairment

The article by An and co-authors1 in this issue of Ophthalmic Epidemiology, highlights a couple of issues: (1) the concept of temporality, a regular concern in cross-sectional epidemiologic studies, and (2) secondary public health concerns related to visual impairment, which usually vary little within and between developed and developing nations. Little has been written about the issue of secondary public health needs related to visual impairment, so the paper by An and colleagues also highlights the need for more research in this area and for other causes of visual impairment.

One of several criteria for assessing causality in an epidemiologic study is temporality. This criterion is difficult to establish in cross-sectional or retrospective study designs. Diabetic retinopathy associated with type II diabetes provides a vision-related example of temporality and the cycle of correlated behaviors and vision that could perhaps lead to further vision loss. Behavioral choices, such as little exercise and excess food consumption, that lead to weight gain are associated with the development of type II diabetes and complications including diabetic retinopathy. Visual impairment can lead to limited access to varied diets and physical activity2 and thus potentially lead to further exacerbation of diabetes-related complications including diabetic retinopathy. The vicious cycle then continues and the original question of temporality is moot.

Another example of the inter-related, cyclical nature of exposures and outcomes comes from research about age-related macular degeneration (AMD). Low levels of physical activity have been shown to be associated with AMD,3,4 AMD and Alzheimer Disease are associated,5,6 and activity loss has been shown to be associated with cognitive decline in AMD.7 Again, it is difficult to tease out the temporality of these associations and in the end, it may not matter. The associations support the promotion of healthy lifestyles for everyone.

The authors noted that time since onset of vision loss was associated with consumption of fast food but not with physical activity. The assumption was that recent onset of vision loss had not allowed time for people to adapt to it. As they quote, the duration of vision loss has been found not to be associated with activities or quality of life as people may not automatically adapt or learn alternative strategies for the activities that they can do.7 Thus it is important that people with recently diagnosed vision loss are referred for rehabilitation and training.

Critical issues in designing services for vision-related disability secondary to an eye disease are determining an individual’s specific needs for rehabilitation and training. In relation to shopping, the activities that can cause difficulty are safe mobility while walking or using public transport, orientation in shops and finding objects on crowded shelves. At home for food preparation, difficulty can be experienced opening packaging, reading instructions in very small print, concern about spilling and breaking things, and operating household appliances. There are solutions for many of these activities either with equipment such as scanners and low vision devices and training in skills. Referral to low vision clinics and rehabilitation agencies can assist people with many of these issues. What is critical is to use a checklist of visual functioning and quality of life that can assist in the design of individualized programs.7,8

Similarly with access and participation in physical activity and facilities, support from peer support or self-help groups, healthcare providers and rehabilitation services can address the barriers faced by people with vision loss.9,10 For the participants in the study by An and co-workers it is knowledge and safe access that limited their participation in physical activity. Attitudes in the community, be it family, the community generally, or providers of physical activity such as gymnasiums, are also contributing factors to participation for people with impaired vision. Advocacy by governments and organizations such as the Korean Retinitis Pigmentosa Society (KRPS) can address some of these barriers.

The participants with retinitis pigmentosa (RP) had significantly greater use of protective health care than the comparison population without any visual impairment. Possible reasons for the positive health behavior could be due to contact with the health system and availability of social security benefits in Korea for people with disability which could make access to health care easier. Membership of a support group such as the KPRS could also explain in part this greater use of protective health services.

The findings from this study in Korea on people with RP are likely to be able to be generalized to people from other countries and to other causes of vision loss. There are many examples of quality of life and activity inventories that have been used across countries and found to be relevant, sometimes with no or very little modification. The National Eye Institute Visual Functioning Questionnaire (NEI-VFQ 25) is an example of a visual functioning and quality of life tool that has been used in multiple countries with minor modification such as by omitting items on driving that are not relevant to a population with low vision.8,11 These questionnaires have also been used in a population with a range of causes of low vision suggesting that the results from this Korean study have implications for other countries and beyond for people with RP.

DECLARATION OF INTEREST

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.