Colour blindness: a hidden vision condition many don’t realise they have

Despite being prevalent among Indians, knowledge and understanding of colour blindness in India is extremely poor. Most of the general population believes that colour blindness is when one sees the world only in shades of black and white. But this is not the case: most people with colour blindness cannot discriminate only between certain colours, namely red-green or blue-yellow combinations. The disorder is congenital and thus, many people may be unaware of their condition all their lives.

Indian scenario

According to various studies in India, around 8% of men and 0.5% of women suffer from colour blindness, which means almost 70 million Indians are potentially colour blind. Red-green type of this vision problem is the most common type of colour blindness, caused by a gene mutation located on the X chromosome. Thus, since men have just one X chromosome, they are much more susceptible to inheriting this condition from their parents compared to women.

A serious problem with colour-blindness is that this condition influences one’s life unnoticed. Common problems that people with this condition might face on daily basis range from the serious to the minor: misinterpreting traffic lights, a negative impact on academic performance of students, an inability to match clothes, problems working with color-coded charts or maps, issues with choosing ripe fruit, and problems with interpreting colour signals. Many of these issues can go unnoticed until the person gets diagnosed with the problem.

When to see a doctor

It should be noted that there are multiple types of colour blindness. For example, red-green is the most common type, while blue-yellow type and complete colour blindness are rather uncommon. Besides, while this problem is usually genetic, it can also develop due to diabetes mellitus, glaucoma, cataracts, retinal diseases, optic nerve disease, brain injury, with ageing and certain medicines.

Any changes in colour vision should be checked by an ophthalmologist, as it can mean an underlying serious eye or neurological condition.

Testing of colour vision is necessary for children and adults who have diabetes or any chronic eye diseases. Unfortunately, colour blindness awareness is not high enough in India to allow for testing in schools for every child.

Addressing myths

There are also certain myths that should be addressed. First of all, it is a misconception that colour blindness leads to total blindness. It also has no connection to intelligence. Despite the fact that there are no ways to treat genetically-determined colour blindness permanently, some individuals can be helped by colour-filter glasses, which allow for discriminating between different colours. However, there is no permanent cure for colour blindness.

Schools, workplaces, and other areas use colour codes extensively, making the creation of colourblind-friendly environments necessary. Teachers and other educators need to be aware that students should not be punished for colour blindness.

Accommodating this need in individuals may involve the use of labels instead of colours, adding patterns or symbols, improving lighting, and using certain apps that can help identify colours.

(Dr. Lakshmi S. is head, clinical services, Dr. Agarwals Eye Hospital, Chennai. omprakash.lakshmi@yahoo.com