All About the Different Types of Alopecia

12 September, 2020
Androgenetic alopecia is the most common cause of baldness in the general population. Still, there are other types of hair loss with different underlying reasons. Learn more with us!
 

Alopecia refers to abnormal hair loss. Contrary to popular belief, there isn’t just one type of this condition. In fact, there are several. We’ll look at the different types of alopecia in this article.

According to scientific studies, this pathology is divided into classes according to its speed of presentation, antecedents, accompanying diseases, and clinical criteria, such as its extension, the hair’s characteristics, and the level of involvement of the underlying skin.

Furthermore, several bibliographical articles stipulate that androgenetic alopecia (the most common variant) affects 6 to 12 percent of women between 20 and 30 years old and 55 percent of men over 70 years of age.

As you can see, it’s highly prevalent. Additionally, it can come with other underlying diseases. For that reason, it’s necessary to learn about the types of alopecia in order to be able to treat them all.

Types of alopecia

When it comes to the different types of alopecia, there’s a broad variety. For that reason, it’s almost impossible to speak of general patterns and symptoms. Its extension is worldwide. However, it does have some peculiarities regarding race and geographical distribution.

Alopecia is defined as the loss of hair of any type and anywhere on the skin’s surface. To facilitate their diagnostic algorithm, clinical hospitals divide this pathology into two large groups:

  • Those with a normal or healthy scalp (non-scarring).
  • Those with a pathological scalp (scarring).
 
A man with alopecia grabbing his head.

Non-scarring alopecia

All the variants that we’ll be talking about next have one common characteristic. Basically, the hair loss isn’t caused by the appearance of fibrous tissue that cancels the follicle. In these cases, there isn’t a destruction of the hair follicle, however, it does present various changes.

Androgenetic alopecia

Androgenetic alopecia is the most common variant of this condition. In fact, various studies report that it covers about 95% of cases. As we said before, up to 55% of men suffer from it, while the percentage in women is around 10%.

Dermatological magazines report that there are two main causes of this disease:

  • Androgens and skin. The increased action of male hormones (testosterone) on certain areas of the scalp promotes a decrease in the activity of the hair follicle until it atrophies.
  • Cell mechanism. This depends on each individual’s hereditary component. Basically, certain genetic factors condition the activity of RNA polymerase, an essential enzyme for protein synthesis. This, as a result, can modify hair growth patterns.

There are multiple treatments to alleviate androgenetic alopecia, such as the use of minoxidil, melatonin, finasteride, or laser therapy. Some of these drugs keep the hair from falling out so you can say they’re effective up to 90%, which is pretty great. On the other hand, it’s pretty difficult to make the hair follicle regrow.

 

Read also: Herbs and spices for hair growth

Alopecia areata

Research shows that this type of alopecia, characterized by the appearance of round patches in focal areas, is a very little known pathology. Experts believe that various factors condition its appearance:

  • Genetics. In up to 40% of cases, the presence of alopecia areata in the family history promotes the appearance of it in the offspring.
  • Immunological. Different pieces of research have reported that there’s a relationship between this pathology and immune disorders, such as thyroid diseases or vitiligo (destruction of skin melanocytes). It’s also been linked to diseases such as anemia, diabetes, or rheumatoid arthritis.
  • This disease also appears to be related to emotional factors such as stress, infectious agents, and neurological variations.

Other types of non-scarring alopecia

We’ve described the two most important types of non-scarring alopecia. There are many more, but we’re going to limit ourselves to commenting on them briefly.

  • Traumatic alopecia. This occurs when there’s continuous damage to the scalp based on traction and pressure, such as tight braids or bows.
  • Diffuse. This refers to the generalized reversible hair loss. It can occur acutely or chronically.
  • Due to lack or excess of vitamins or drugs (whether legal or illegal). Studies show that a deficiency of vitamin D or an excess of vitamin A can cause hair loss.
A middle-aged man with alopecia areata, one of the most common types of alopecia.
 

Scarring alopecia

According to scientific articles, the main characteristic of scarring alopecia is permanent hair loss, which is replaced by fibrosis or hyalinized collagen. This type of pathology accounts for 3% of the alopecia observed in dermatological centers. For that reason, its clinical importance is relatively low.

Here are some of the factors that can promote this type of baldness:

  • Physical causes. Burns, frostbite, trauma, among others. Destroyed hair follicles are replaced by scar tissue, which prevents the hair from proliferating again.
  • Tumors. Any tumor that affects the skin, both benign and malignant, can have the appearance of this pathology as a side effect.
  • Infections. Those diseases that permanently damage the skin, such as leprosy or skin tuberculosis, can also cause it.
  • Chronic inflammatory processes. For example, lupus erythematosus and other non-infectious diseases that cause skin lesions can damage the hair follicle.

Read also: Multiple pilomatrixoma syndrome

What you should remember about the different types of alopecia

As you can see, there are two divisions of alopecia: non-scarring and scarring. There are different types of non-scarring alopecia depending on the focus of hair loss and the underlying reasons. However, they’re usually conditioned by genetic and hormonal factors. On the other hand, scarring alopecia is due to trauma and wounds that generate scarring in the place of the hair follicle.

There’s something we must make clear here. Androgenetic alopecia is the most common variant of this disease, which mainly affects middle-aged men. Fortunately, there are many treatment options to alleviate it and stop hair loss.

 
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