As cataract surgeons, I sometimes wonder how many of our patients we quietly write off without meaning to. We don’t say it aloud, of course, but when someone in their later years comes in with cognitive decline, there’s often an unspoken assumption: Is cataract surgery really worth it? Perhaps we tell ourselves their quality of life won’t improve, or that the risks are too high, or that “they won’t manage the drops after surgery.” But are we, as surgeons, guilty of lowering the bar for this group – precisely when they need us most?
Dementia isn’t just about the brain
The first thing to acknowledge is that dementia complicates visual perception in ways we don’t always appreciate. Neuronal loss in the parietal and occipital lobes disrupts visual processing, so a patient’s world is already visually confusing before we add cataracts into the mix. Now imagine layering on multifocal spectacles, reduced contrast sensitivity, or the wrong refraction. For many, this becomes a recipe for increased falls, loss of independence, and accelerated decline.
The literature is unequivocal, falls can be a terminal event in people living with dementia and sight is complicit in this – plus, varifocals increase fall risk in older people, as well as dementia itself multiplying the risk of falling. And yet we continue to discharge patients from our clinics with precisely these pitfalls in place.
Timing matters – “Fix the roof while the sun is shining”
A patient with dementia may not tell us they can’t see, and they won’t necessarily book their own optometry appointments. Visual symptoms will all too often be attributed solely to “the dementia.” By the time they are referred, visual function is often severely impaired – which means we need to be proactive.
This is not about rushing everyone to theatre straightaway. But it is about asking harder questions: Is their visual impairment contributing to their functional decline? Are their glasses out of date? Are carers struggling because the patient refuses spectacles? Will things get worse if we wait?
Cataract surgery should never be delayed until the point of crisis. Dementia is progressive and cataracts are treatable, and so we must seize the moment when the patient can still cooperate, still benefit, and still find joy in the clarity of sight. We must, as the old saying goes, fix the roof while the sun is still shining.
Anaesthesia anxiety
One of the most persistent myths is that general anaesthesia (GA) is contraindicated in dementia. Yes, post-operative cognitive decline (POCD) is a real concern after major surgeries like hip fractures or cardiac bypass. But we must remember that cataract surgery is not a hip replacement, and the evidence shows GA for cataract is no more harmful than local. Avoiding surgery purely on this basis is unjustifiable.
Rethinking refractive targeting in dementia
So, what should we be aiming for? For most patients with dementia, emmetropia remains sensible. But if driving is off the table, a slight myopic target can sometimes be a gift for near tasks.
What about diffractive multifocals? In my personal view, they should be avoided. The brain already struggles to process a single clean image, so why present it with three?
Extended depth-of-focus (EDOF) IOLs may have a role, particularly for those with carers who can support spectacle independence. But “primum non nocere” must remain our guiding light – for many, the simplest monofocal lens aiming for mild myopia of -1 is still the kindest choice.
The dementia–cataract paradox
Here’s the irony: emerging data suggest that cataract surgery may reduce the risk of dementia progression. A recent JAMA Neurology study showed a 29% lower risk of subsequent dementia in patients who underwent cataract extraction. Other large-scale datasets echo this association. While causation is always slippery, it’s hard not to see a pattern: vision restored, quality of life improved, social engagement preserved – and cognitive decline slowed.
So, while massive resources are being poured into marginally effective dementia drugs (over $42 billion in the last 30 years), a £900 cataract operation in the UK may quietly offer more impact than we give it credit for.
Why are we holding back?
And yet, we underserve this group – carers don’t advocate; optometrists don’t always push for referral; GPs think “what’s the point?” Even we, the surgeons, hesitate. And what’s the result? Visual decline is blamed on dementia, not cataract – and the opportunity for life-changing intervention is lost in the maelstrom of hesitation.
If one in 20 people aged 70–80 is living with dementia, and one in five over 80, this is not a niche problem; this is our daily work. Every clinic, every week, presents us with these patients. And every time we hesitate, a patient’s world grows dimmer.
A call to arms
So let me say it plainly: it is up to us, the ophthalmologists. The evidence is there. The risks are low. The benefits can be profound. Cataract surgery is not futile in dementia – it is essential for quality of life.
And if we, as surgeons, do not step up, then who will?
We must challenge our assumptions, resist therapeutic nihilism, and remember that every patient – with dementia or not – deserves the chance to be able to see clearly.
