Research shows that between 5 and 50% of children with Down Syndrome (DS) under the age of 17 years will develop cataracts 1. In 3-5% of cases the development of cataracts is in the infantile period or is congenital. It is possible that a gene dosage effect of one of the cataract genes on chromosome 21, such as CRYAA may be responsible for these cataracts 1.
Diabetes is associated with cataract formation as it significantly impacts the structural, physical and metabolic properties of the cornea 8. While there’s no research reporting a connection between diabetes type 1 and cataracts in the DS population, the incidence of type 1 diabetes is higher in the DS population and it would be wise to have glucose and HbA1C levels tested 8.
Heavy Metals Lead and Cadmium have been found in the lenses of cataract patients, suggesting these metals play a role in cataract risk 11. Exposure to heavy metals, such as lead and cadmium, can lead to oxidative stress through depletion of glutathione and sulfur and inhibition of the antioxidant defence system 11.
Another cause of cataracts in presenile populations is dehydrational crises resulting from chronic diarrhea or heatstroke 12. Oxidative stress is also linked to cataract development 13. Opacity of the lens is the direct result of oxidative stress. Cataracts are common in diabetes where superoxide is elevated in the mitochondria as a result of hyperglycaemia 13. Using antioxidants which target superoxide are recommended.
Despite good surgical outcomes, cataract surgery failed to improve visual outcomes due to other eye issues 4. Surgery has its limitations and complications such as iris prolapse, raised IOP, infection, cystoid macular oedema and posterior capsular opacification (PCO) 4.
More robust and natural ways to prevent cataracts are being sought after. The inclusion of preventative foods and nutraceuticals is proving a great preventative of cataracts because of their safety and nutritional and therapeutic benefits 14.
Natural Eye Protection
Astaxanthin and Lutein are carotenoids made from dark leafy green plants such as kale and spinach. They target tissue sites such as the retina where they keep tissue healthy 6, 7.
Astaxanthin reduced lens opacity, and prevented loss of glutathione from the eye lens in a recent study, making it effective at reducing cataracts induced by unstable blood glucose levels 6. Also, the antioxidant properties of lutein give it a protective function in diabetic retinopathy, although this hasn’t been studied as well as its benefits for Macular Degeneration 7.
Dietary concentrations between 6 and 20 mg per day of lutein have been associated with a reduced risk of eye disorders such as cataracts and age-related macular degeneration 7. The effects of lutein and other antioxidants in preventing early onset age related ocular and neurological diseases are well documented 7.
While the mechanism of action is not entirely understood, bile acids are showing promise in protecting eyes from developing cataracts in the presenile population by acting on eye mitochondria and regulating the eye cell cycle 2. It is thought that abnormal production of bile acids leads to increases in cholestanol and cholesterol which accumulate in the central nervous system, leading to various symptoms of cataract formation 3. People with DS are reported to have anatomical abnormalities associated with the biliary system, and its possible this could contribute to cataract formation 10.
Recent research reports the supplemental and dietary Vitamin E intake is associated with reduced cataract formation 9. Low levels of Vitamin C, Vitamin A, Lutein and Zeaxanthin are associated with cataract formation, so adding these to your diet will help prevent progression 6.
Diet and the inclusion of foods and phytonutrients high in antioxidants including EGCg, Resveratrol, Grapeseed extract and CoEnzyme Q10 are considered the optimal treatment for cataracts, as alternatives to surgery are sought after 14.
References
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1857194/
1. Down’s syndrome and early cataract
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2798994/
2. Bile acids in treatment of ocular disease
https://jamanetwork.com/journals/jamaophthalmology/fullarticle/4186383.
3. Presenile Cataract: Consider Cholestanol
http://bjo.bmj.com/content/98/9/12734.
4. Cataract surgery outcomes in adult patients with Down’s syndrome
https://www.hindawi.com/journals/cggr/2012/974253/
5. Ophthalmic Disorders in Adults with Down Syndrome
https://www.ncbi.nlm.nih.gov/pubmed/25110808
6. Effect of astaxanthin on cataract formation induced by glucocorticoids in the chick embryo.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3708350/
7. The Role of Lutein in Eye-Related Disease
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3589218/
8. Cataracts in Diabetic Patients: A Review Article
https://www.ncbi.nlm.nih.gov/pubmed/25591715
9. Vitamin E and risk of age-related cataract: a meta-analysis.
http://adc.bmj.com/content/85/3/242
10. Cholelithiasis in Down’s syndrome
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5086441/
11. Cadmium and Lead Exposure and Risk of Cataract Surgery in U.S. Adults
https://www.ncbi.nlm.nih.gov/m/pubmed/2930754/
12. Dehydrational crises: a major risk factor in blinding cataract.
https://www.ncbi.nlm.nih.gov/m/pubmed/16765571/
13.Oxidative stress in cataracts.
https://www.sciencedirect.com/science/article/pii/S1319453416300911
14. Nutraceuticals in prevention of cataract – an evidence based approach.
