Causes of Alopecia Areata
Alopecia areata is a type of autoimmune disorder. In this condition, the immune system mistakenly attacks hair follicles. Hair follicles are the structures from which hair grows. Because of the faulty immune response, the follicles become smaller and stop producing hair, becoming the primary alopecia areata reason.
Alopecia areata can lead to patchy hair loss on the scalp or other areas of the body such as the eyebrows, eyelashes and face. In some cases, the onset is sudden while in others, it may develop slowly over the years. The condition can recur throughout the lifetime of an individual.
In severe cases, alopecia areata can progress to the 2 conditions mentioned below:
• Alopecia Totalis: It is an autoimmune condition that causes complete loss of hair on the scalp.
• Alopecia Universalis: It is the most severe form of alopecia areata which causes complete hair loss over the entire body.
The exact reasons for alopecia areata are not known. However, there can be certain contributory factors and underlying medical conditions that may act as alopecia areata causes.
Risk Factors for Alopecia Areata
• Family History
It is one of the most common reasons for alopecia areata. If you have a family history of alopecia areata, or any other autoimmune conditions like type 1 diabetes or rheumatoid arthritis, it may act as a risk factor for you. According to Harvard Medical School, almost 40% of the people less than 30 years of age with alopecia areata have at least one family member who has been diagnosed with the same disorder. Hence, it is one of the chief alopecia causes.
• Comorbid Conditions
If you suffer from certain autoimmune diseases or atopic conditions as listed below, they may become alopecia areata causes:
- Asthma: It is a respiratory condition that causes the tubes that carry air to and from the lungs to become inflamed, swollen and narrow. This leads to difficulty in breathing. According to Harvard Medical School, the risk of developing alopecia areata is unusually high in people who have asthma. Hence, asthma can be a reason for alopecia areata.
- Allergic rhinitis: An allergy occurs when the immune system reacts abnormally to foreign substances that are not typically harmful to the body. Allergic rhinitis or hay fever is a type of inflammation in the nose, which occurs when the immune system overreacts to allergens in the air. According to an article in the journal - Experimental Dermatology, allergies may contribute to the onset and relapse of alopecia areata. Hence, it can act as an alopecia areata trigger.
- Eczema: It is a condition that causes inflammation of the skin, leaving it red and itchy. It is generally seen in infants but can occur in people of all ages. The most common form of eczema, atopic dermatitis; can be one of the alopecia causes.
- Stress, anxiety or depression: The primary alopecia areata reason is a mistaken response of the immune system that leads to destruction of the hair follicles. Extreme stress, anxiety or depression may be responsible for triggering such an immune response, thus working as an alopecia areata trigger.
- Thyroid diseases: When the immune system mistakenly attacks the thyroid gland of our body, it can lead to thyroiditis or Hashimoto’s disease (inflammation of the thyroid gland). It causes overproduction or underproduction of the thyroid hormones. According to the British Thyroid Foundation, alopecia areata is more common in people with autoimmune thyroid diseases. Therefore, thyroid diseases can be one of the important alopecia causes.
- Vitiligo: According to a study published by the National Centre for Biotechnology Information, the immune cell populations and cytokines that drive vitiligo and alopecia areata are similar. They are closely associated with patients and their family members. Vitiligo and alopecia areata have common genetic risk factors, suggesting that they share a similar pathogenesis. Therefore, vitiligo may, in some cases, become an alopecia areata trigger.