Have you had your eyes tested lately?
Cells in the retina that are responsible for normal colour vision decline in sensitivity as we age, causing colours to become less bright and the contrast between different colours to be less noticeable. You may not notice it as it has happened slowly over time but it might be worth getting your eyes checked. Particularly if you are over 70.
The blue-yellow spectrum loss is mostly from the development of cataracts especially the nuclear sclerotic type and because it is a gradual process of hardening of the crystalline lens of the eye, most people don’t notice the changes until after they have cataract surgery on one eye and then they see the difference between the two eyes.
Abnormal colour vision increases significantly with aging — affecting one-half or more of people in the oldest age groups, reports a study in Optometry and Vision Science, the official journal of the American Academy of Optometry. The journal is published by Lippincott Williams & Wilkins, a part of Wolters Kluwer Health.
While few people younger than 70 have problems with colour vision, the rate increases rapidly through later decades of life, according to research by Marilyn E. Schneck, PhD, and colleagues of The Smith-Kettlewell Eye Research Institute, San Francisco. They write, “We find the colour discrimination declines with age and that the majority of colour defects among the older population are of the blue-yellow type.”
The researchers administered colour vision tests to a random sample of 865 older adults — age range 58 to 102 years. The study excluded subjects with any type of congenital colour-vision defect (“colour blindness.”). The types and rates of colour vision abnormalities were assessed in different age groups.
Overall, 40 percent of the participants had abnormal results on one of the two colour vision tests used in the study. Twenty percent failed both tests.
The failure rate was markedly higher in older age groups. Although colour-vision abnormalities were uncommon in people younger than 70, they were present in about 45 percent of people in their mid-70s, up to 50 percent of those 85 and older, and nearly two-thirds of those in their mid-90s.
Nearly 80 percent of the abnormalities involved confusion of the lighter (pastel) shades of blue versus purple and yellow versus green and yellow-green. These “blue-yellow” errors are distinct from the “red-green” (Protan Deutan Colour Blindness) errors observed in people with inherited colour blindness, which affects about eight percent of males and 0.5 percent of females. Although the two tests had different failure rates, they detected similar frequencies of blue-yellow errors.
More Severe Defects May Affect Daily Functioning
The results confirm previous studies showing that colour vision “deteriorates measurably” with aging. Most subtle aging-related colour vision abnormalities are likely to go unnoticed, the researchers suggest.
However, they note that nearly 20 percent of older adults failed the easier of the two tests, “designed to only detect defects sufficiently severe to affect performance in daily life.” Dr Schneck and co-authors note, “These individuals would have problems carrying out some tasks that rely on colour vision.”
The researchers discuss factors that may contribute to changes in colour vision with aging, and to blue-yellow defects in particular. These may include reduced pupil size, admitting less light into the eye; increased yellowing of the lens inside the eye; and changes in the sensitivity of the vision pathways. All of these are known changes with age to the human eye.
Increased rates of eye diseases are another potentially important contributor. Dr Schneck and co-authors add, “The most common age-related eye diseases (glaucoma, age-related macular degeneration, and diabetic eye disease) all produce blue-yellow colour vision anomalies, at least in the preclinical or early stages.”
While there is no treatment for this normal, age-related loss of colour perception, you should be aware of this loss if your profession requires fine colour discrimination. If you think you aren’t seeing colours as you should, head to our practitioner page to find a colour vision Optometrist near you.
Materials provided by Wolters Kluwer Health: Lippincott Williams & Wilkins. Note: Content has been edited for style and length.
1. Gunilla Haegerstrom-Portnoy, Marilyn E. Schneck, Lori A. Lott, Susan E. Hewlett, John A. Brabyn. Longitudinal Increase in Anisometropia in Older Adults. Optometry and Vision Science, 2014; 91 (1): 60 DOI: 10.1097/OPX.0000000000000114
Wolters Kluwer Health: Lippincott Williams & Wilkins.
Reprint form “Colour vision problems become more common with age, study shows.” ScienceDaily. ScienceDaily, 20 February 2014. <www.sciencedaily.com/releases/2014/02/140220102614.htm>.