The world has seen dramatic improvements in health and life expectancy over the last century. People are now living healthier and longer lives, particularly in industrialized countries – a result of improvements in environmental and public health, as well as in nutrition and physical safety. However, as life expectancy has increased, so too has the number of people living with age-related degenerative diseases.
Foremost among these in the news are the projected rise in dementia and the forecasted tsunami of health problems related to higher rates of diabetes. Less prominently in the news, but probably as important in terms of the numbers of people affected, are the degenerative eye diseases of later life comprising cataract, AMD, glaucoma, and diabetic retinopathy.
In the UK, rates of visual impairment are 20 percent in people age 75 and older, and 50 percent in those aged 90 and over. Two thirds of these are women, and people from black and minority ethnic communities are at significantly greater risk of losing sight. Currently, there are over 2 million people in the UK who have daily problems with their sight. By 2050, projections double this number to over 4 million.
A report from Deloitte Access Economics estimated that the cost of sight loss in the adult population of the UK totalled £28.1 billion (~$35.14 billion) in 2013. This figure comprises both direct and indirect costs – and the costs associated with reduced health and well-being. The figure has increased dramatically from £22 billion (~$27.5 billion) reported in 2008.
For healthcare providers, the problem is particularly problematic through increasing numbers of patients presenting for care. In 2015–2016, 16.3 million people underwent NHS sight tests with an optician. A further 8.2 million people attended hospital eye service appointments. Around 396,000 cataract operations were performed and 2.9 million people with diabetes were underwent retinopathy photographic screening. There are currently 5.8 million people with sight threatening conditions in the UK. These figures put ophthalmology second only to orthopaedics and trauma as the busiest sector of the NHS in the UK.
AMD is by far the most common cause of registered visual loss in the UK. Although the numbers of those affected are increasing in absolute terms, the age-specific rates of disease are now clearly dropping in western European countries – thanks to improvements in public health, and more effective interventions, such as anti-VEGF treatments. Smoking is well known to be a strong modifiable risk factor for AMD.
The public places smoking ban introduced in the UK in 2007 will almost certainly reap enormous benefits in the future: in the same way that traumatic eye injuries almost disappeared from ophthalmology departments following the seatbelt legislation introduced in 1983, the smoking ban will have a lasting, significant, beneficial impact on rates of AMD.
Sadly, a similar, pragmatic and effective public health intervention for diabetes is proving elusive. Rising rates of obesity need changes in dietary habits and exercise, which are not easy to achieve. The smoking ban will also help drive down the rate of cataract development. However, once again, this benefit will probably be counter-balanced by rising rates of diabetes. Cataract surgery is one of the most effective interventions ever developed by modern healthcare and at least in this regard patients can look forward to a relatively straightforward and low risk way of improving their vision.
Probably the greatest scientific challenges presented by the four common diseases of later life relate to glaucoma. Though we have now confirmed and quantified the role of intraocular pressure, and clearly documented the benefits of lowering IOP, our understanding of the etiology of this condition has not changed in a meaningful way in the last hundred years.
IOP remains the sole, proven, modifiable risk factor. The disease is now well known to be a polygenic abnormality, probably influenced by mutations in around 200 locations in human DNA. However, effective interventions based on genetic risks have proven elusive. The drive towards risk stratification using elevated intraocular pressure have not given any benefits – screening for glaucoma is not viable.
In fact, the introduction of guidelines for England and Wales for referral of all those people found to have IOP >21 mmHg only served to generate three-fold increase in referrals, without any increase in detection of sight threatening glaucoma. Two things are now desperately needed: firstly, other modifiable risk factors need to be identified for this condition. Secondly, and most importantly, we need better ways of identifying the small number of patients who will progress to develop significant sight loss within their lifetime.
Rising to these challenges in the “age of austerity” is no easy feat. However, solutions are at hand, as my Moorfields colleagues outline in the pages of this issue of The Ophthalmologist. Conceptually, these fall into three broad categories: People, Processes, and Technology. Training the global workforce to deliver the highest standards of medical care regardless of where they work makes education a core part of our agenda.
Developing newer ways of working, to deliver more efficient models of care is a subject of great interest to many. Virtual clinics and telemedicine allow us to monitor the enormous number of patients who need ophthalmic surveillance, but are currently stable and do not need procedures or changes in medication. Finally, in the “post-human genome project” era, where big data and AI are all the rage, technological advances look set to truly revolutionize the way ophthalmology is practiced.
