Circular hair loss (alopecia areata)

Overview: What is circular hair loss?

The first signs of circular hair loss (alopecia areata) usually appear unexpectedly: Suddenly, round, hairless patches appear where hair was previously visible. In most affected individuals, only the hair on the head is affected. In rare cases, however, eyebrows, eyelashes, beards, or other hairy parts of the body may also be affected by hair loss.

In most cases, circular hair loss results in only a few isolated “patches” of baldness. However, there are also less common subtypes with a different appearance:

• In alopecia areata totalis , the hairless areas merge into one another until the entire head is bald.
• In alopecia areata universalis, the entire body is affected by hair loss.
• In ophiasis-type alopecia areata, the hair on the nape or back of the head disappears.

The cause of alopecia areata has not been definitively determined. They believe that the body’s own immune system plays a crucial role. Presumably, its immune system is not directed against pathogens, but against its own body. More specifically: against the hair root (follicle). This causes inflammation, which disrupts hair growth and ultimately leads to hair loss.

Circular hair loss – frequency and age

Alopecia areata affects men and women equally. People of all ages can be affected, including children. However, young adults are affected by alopecia areata more often than average.

Alopecia areata is not a rare condition: About 1–2 percent of the population receives this diagnosis at some point in their lives. For Switzerland’s 8.7 million residents, this means that approximately 85,000 to 175,000 of them have experienced alopecia areata at some point, are currently suffering from it, or will develop it in the future.

Circular hair loss: What are the causes?

Even though circular hair loss (alopecia areata) is rarely directly inherited, genetic factors appear to play a role. Various genes have been identified that are, or may be, involved in the development of alopecia areata. For those affected, this means:

• In first-degree relatives, the inheritance risk is between 6 and 8 percent.
• There is no increased risk of circular hair loss in second-degree relatives: At around 1 to 2 percent, it corresponds to the risk of the population as a whole.

Circular hair loss is likely an autoimmune disease. This means that the immune system turns against the body itself. Apparently, certain white blood cells (T lymphocytes) attack the hair roots. Although they do not destroy these cells, they trigger inflammatory reactions that lead to alopecia (hair loss).

It is considered a fact that alopecia areata is caused neither by malnutrition nor by hormones. Environmental factors also do not appear to play a role: the disease was already described in ancient times.

Symptoms: How does circular hair loss manifest itself?

In most cases, circular hair loss on the scalp results in a bald patch with a diameter of 1–2 centimeters. Bald spots often follow. The affected patches are not always perfectly circular or round, but they are clearly demarcated from the hairy area surrounding them. Alopecia areata does not cause pain, but it may be accompanied by mild itching.

In the majority of affected individuals, no more than two bald spots develop. However, alopecia can also spread further—to the point of complete loss of scalp hair or even all body hair.

Prognosis: How does circular hair loss progress?

The course of alopecia areata cannot be predicted. For some people, the alopecia goes away on its own after six to twelve months and never returns. In other patients, the lost hair also grows back, but at some point, the circular hair loss reoccurs. Still others experience no improvement at all, not even temporarily. About 20–30% of those affected suffer from permanent hair loss.

Even chronic alopecia areata has no effect on life expectancy. However, alopecia areata can certainly affect one’s emotional well-being.

Self-Help Groups

Talking with others who are going through the same thing can be a great source of support when coping with an illness. If you are looking for a suitable self-help group , you can get advice from Selbsthilfe Zürich. Selbsthilfe Zürich and the University Hospital of Zurich are partners in the national project “Health Literacy Through Self-Help-Friendly Hospitals.”

Therapy: How is circular hair loss treated?

Since the mechanisms underlying circular hair loss are not fully understood, it cannot be cured. Nevertheless, various medications are available to treat the symptoms. Their effects usually wear off as soon as you stop taking them.

Among others, the following medications are used to treat alopecia areata:

• Minoxidil is an active ingredient that stimulates the hair roots (follicles), which is intended to promote hair growth.
• Cortisone is intended to stop inflammatory reactions at the hair roots.
• Diphenylcyclopropenone (DCP) produces an allergic reaction on the scalp.It is designed to attract the immune system to itself so that its activity is bound and no longer directed against the follicles.
• Baricitinib is a novel active ingredient that influences the immune system and has anti-inflammatory properties.Baricitinib has been approved for the treatment of alopecia areata in the USA since 2022.