Cataract surgery reduces the risk of dementia by up to 30%

Research carried out by the University of Washington recently revealed that people who choose to have cataract surgery are nearly 30% less likely to develop dementia than people who decide to leave their cataracts untreated: 

“Analysis showed that subjects who had cataract removal surgery in either eye were about 30% less likely to develop any form of dementia for at least 10 years after their surgery.”  

Source: Dementia risk drops after cataract surgery (University of Washington, 26th January 2022)

The ‘Adult Changes in Thought’ study has been ongoing for several years and is based on a large sample of 5000 people, all aged 65+. 3038 participants were diagnosed with cataracts either before or during the study and after taking into account variables including race, smoking and biological sex, researchers concluded that cataract removal was associated with a lower risk of developing dementia. The study also found that having cataract surgery within five years of diagnosis was more effective at reducing the risk of dementia than if surgery took place after five years.  

Participants in the study have their cognitive abilities evaluated every two years and those who opted to have at least one of their cataracts removed following diagnosis showed less cognitive decline over a sustained period of time.  

Researchers have yet to conclusively determine the reasons why having cataracts surgically removed helps to reduce the risk of dementia, but they think it’s because having cataract surgery restores people’s vision and the increased visual stimuli helps to keep their brains active. People who don’t have surgery often find their vision deteriorating, and this can lead to social isolation (i.e. not being able to drive) and reduction in social activities and exercise, which in turn contribute to cognitive decline.  

Cataracts can also block blue light – a light which has many health benefits, including regulating our sleep pattern, keeping us awake and alert during the day, boosting our memory and cognitive function and improving our mood. Too much blue light is linked with eyestrain, but not enough can also be equally harmful. It follows, then, that having cataract surgery allows people to experience the cognitive benefits of blue light again. 

Lead researcher Dr. Cecilia Lee, associate professor in ophthalmology at the University of Washington School of Medicine, said: 

“This kind of evidence is as good as it gets in epidemiology. This is really exciting because no other medical intervention has shown such a strong association with lessening dementia risk in older individuals.” 

You can find out more about this exciting new development on the University of Washington’s website, but it’s wonderful to know that cataract surgery doesn’t just restore patients’ vision and quality of life, it can have some other significant (and unexpected) health benefits, too! 

If you’ve noticed that your vision is cloudy or blurry, colours look faded, or you’re finding it difficult to see in low light/noticing halos around bright lights, you may have a cataract. It’s important to book an appointment with your optician as soon as possible so they can give you an official diagnosis and discuss treatment options with you.