Alopecia Areata

Alopecia areata is a stress-related condition that causes the hair to fall out in patches. Depending on the severity of the condition, it may be unnoticeable. Alopecia areata is characterised by a patchy type of hair loss, that is, the bald area appears as a rounded bare patch about 2.5 centimetres across.

Alopecia areata is predominantly caused by stress. The condition develops when the immune system attacks the hair follicles, resulting in hair loss.

Alopecia areata is also often prominent in those that meet any of the below conditions:

• Those who have a family history of alopecia areata or any other autoimmune diseases
• Those who have at least 8 of the susceptibility genes
• Those that have higher than expected rates of thyroid disease, vitiligo or atopic eczema 
• Those who have chromosomal disorders such as Down syndrome
• Those who are on biologic medications may find it as a drug-induced mechanism 

The exact mechanism of alopecia areata is not yet understood, but it is histologically characterised by T cells around the hair follicles. These CD8(+)NK group 2D-positive (NKG2D(+)) T cells release pro-inflammatory cytokines and chemokines that reject the hair.

Although alopecia areata is most often caused by stress, this is not the only trigger. It can also be caused by trauma, some viral infections and hormonal changes.

Some who develop alopecia areata may experience it on-and-off for the rest of their lives. However, some may only experience it once. It varies from person to person, although it’s very rarely permanent.

In most cases, alopecia areata will regrow within a year. Even in the most severe cases, the hair will regrow within a year. However, one-third of those that experience alopecia areata will have chronic hair loss.

Those that have chronic, rapid onset or more than 20% hair loss will find that systemic or topical treatments, such as minoxidil, are prescribed to treat alopecia areata.

As alopecia areata often has spontaneous regrowth, there is often not the need for treatment. This also means that there is not a lot of research that has been done on treatments for alopecia areata, especially compared to other forms of hair loss.

Sometimes, topical hair treatments are prescribed, but these are proven to not be overly effective. In particularly extreme cases, systemic corticosteroids may be prescribed. However, these are generally the last resort because of the severe side effects of corticosteroids.

Most commonly, those who have alopecia areata will find it develops over a period of a few weeks, followed by regrowth over several months.

However, if you find that alopecia areata, or suspected alopecia areata, is developing quicker than this, consult your GP. This may be a sign of an underlying health condition.