Categorized | Women's hair loss

Female hair loss types

Contents:

Androgenetic Alopecia

Androgenetic Alopecia (or AGA) is the most widespread hair loss type found in males and females. In its clinical presentation, it develops in females differently than in males and, because of this, it is also called Female Pattern Hair Loss (Baldness)It has been estimated that the prevalence of this type of hair loss among Caucasian females is about 50% by the age of 60.  Recent studies show that 1 in 4 women (25%) in the USA suffer from Female Pattern Hair Loss (FPHL).

savin-ludwig-scale

Two main scales are used by hair loss experts to measure the density of female hair loss

FPHL is a diffuse hair loss, which means that the hair gets thinner and is lost evenly all over the crown.  Unlike males with androgenetic alopecia, females never develop baldness. Two main scales are used by hair loss experts to measure the density of female hair loss: the Savin Scale (3 stages with sub-stages plus Advanced and Frontal hair loss) and the Ludwig Scale (3 grades).They are nearly identical except that the Savin Scale also measures overall hair thinning.

The mechanism of AGA is still not fully understood but it is believed that it is a genetic condition caused by the increased susceptibility of the hair follicles to DHT (dihydrotestosterone, an active form of testosterone) and increased activity of 5-alpha-reductase (the enzyme found in the hair follicles that converts testosterone into DHT).  DHT shrinks the hair follicle and does not allow healthy hair to grow. The root of the problem seems to be in the local excess production of DHT.  There are two points to keep in mind:

Aromatase is the key enzyme that participates in the process of testosterone conversion into specific estrogen in tissues.
• It is believed that estrogen reduces the DHT conversion from testosterone.

It seems most females are usually protected from AGA because they have:

Lower testosterone level (=>less testosterone is converted into DHT);
Lower level of 5-alpha-reductase required to convert testosterone into DHT (=>less DHT is produced);
High level of aromatase (greater amount of testosterone is converted into estrogen rather than in DHT).

Females who experience a decrease in the level of estrogen (such as in a postmenopausal period) and have genetic predispositionto hair loss in that they have more 5-alpha-reductase in their hair folliclesdevelop Androgenetic Alopecia.  The frontal follicles of a woman’s scalp contain a greater amount of aromatase than that of a man’s scalp.

Telogen Effluvium

This is a very frequent type of hair loss but the exact prevalence is unknown.  According to some sources, it is the second most common type of baldnessand the most common type in females.  Many adults have experienced a period of Telogen Effluvium (TE) at one time or another. Such hair loss is diffuse in its nature, meaning that hair falls out evenly all over the head.  Also it more often develops in women rather than in men.

Usually a human hair follicle grows hair from 2 to 4 years during which it is in the growing phase called anagen.  Then there is a resting period of about 100 days. This resting phase is called telogen. While the follicle is resting, the hair changes into club hair.  When a new hair begins to grow it is formed under the resting hair and gradually pushes it out which forces the old hair to fall out.  Normally about 85-90% of the hair follicles on the scalp of a healthy individual are in the growing phase and about 10-15% are in the resting phase.  However, when we are talking about TE, this proportion changes drastically.  This is caused by the follicle transitioning early from the growing (anagen) into the resting (telogen) phase therebysignificantly decreasingthe follicles’ ability to produce hair. This can be caused by serious emotional or physical stress, surgery with general anesthesia, fever, various infections, childbirth, malnutrition, dieting, some drugs (antidepressants, calcium channel blockers, β-blockers, etc.), or thyroid gland dysfunction.

Anagen and telogen phases

Anagen and telogen phases

Telogen Effluvium is most common inpostpartum females – up to 45% of new mums experience it. Thespecial term for such condition is Postpartum Alopecia.  As the hair falls out during the late telogen phase, a woman may notice that she is losing her hair in great amounts 2-3 months after childbirth which has causedan excessive number of hair follicles to enter the resting phase.  At its peak, a woman may notice that she is losing a handful of hair at a time.  In most of the cases, TE is fully reversible; it does not cause complete baldness and the condition ceases once the stressful impact on the body is relieved.  However. in rare cases, Chronic Telogen Effluviumcandevelop.  An individual may suffer with this condition for years without understanding the triggering factors.  For unknown reasons, this conditionaffects predominantly women who are 30-60 years of age.

Anagen Effluvium

This is also a type of diffuse hair loss much like Telogen Effluvium, but it progresses more quickly and may result in losing all the hair on the scalp.  This is most common in patients undergoing chemotherapy (cytotoxic therapy) or radiation therapy. It can be caused by the poisoning with toxic substances like rat poison as well.  About 90% of our hair follicles are in the anagen phase simultaneously at any given time.  Cytotoxic agents and other toxins inhibit the rapid growth of cells including the hair follicle cells which leads to a sudden cessation of hair production and subsequent rapid hair loss.  It is important to realize that this condition is fully reversible – hair re-growth usually starts once the toxic influence on the body is removed.

This table will help to distinguish between Anagen Effluvium and Telogen Effluvium 

Clinical picture Anagen Effluvium Telogen Effluvium
Sudden hair loss after some triggering event 1-4 weeks 2-4 months
% of hair that has fallen out 80-90% 20-50%
Bulb of the fallen hair Pigmented hair bulb White hair bulb (normal)
Hair shaft Broken or shortened Normal

Alopecia Areata

Alopecia areata

Alopecia areata

Alopecia Areata (AA) is an inflammatory-induced hair loss.  The National Alopecia Areata Foundation states that this type of hair loss affects about 2% of the population worldwide including approximately 6.5 million Americans with the lifetime risk of nearly 2%, which makes it one of the most prevalent autoimmune diseases.  About 60% of the patients suffering from Alopecia Areata develop it before the age of 20.  It affects both males and femalesequally in youngage groups, and mainly females in middle-age groups.

AA is characterized by the presence of circular bald spots on the scalp which are well-defined. Usually this condition is asymptomatic; no manifestations are visible until the hair falls out and patients do not experience itching nor pain. It is believed that AA is caused by the autoimmune response of the body – autoimmune dysfunction makes immune systems attack the hair roots.  Such hair loss is associated with a higher risk of other autoimmune disorders (16%), as it can be found in patients with diabetes, vitiligo, thyroid disease, bronchial asthma, etc.  However, AA can even be experienced by healthy individuals. How and why it develops is still unclear.  Some scientists have reported that extreme stress can provoke the progression of this type of hair loss. Scientists have revealed that recent studies show there is a hereditary association in the development of AA and that genes are involved.

AA is a non-scarring type of alopecia. It does not cause the ‘death’ of hair follicles.  Rather, the follicles retain the potential to produce hair and at some point in time they can resume producing hair.  Alopecia Areata has several subtypes:
Diffuse Alopecia Areata – hair is lost diffusely all over the head. Most often the condition tends to progress into Alopecia Totalis and then into Alopecia Universalis. This is the form of AA which is most difficult to diagnose as it can be confused with Telogen Effluvium or Androgenetic Alopecia;
Alopecia Areata Monolocularis – this form of AA is characterized by the presence of only one bald spot on the scalp;
Alopecia Areata Multilocularis – this the stage after Alopecia Areata Monolocularis, when multiple bald spots of different sizes appear on the scalp;
Alopecia Areata Barbae – the condition affects only the beard and therefore only evident in males;
Alopecia Totalis – a person suffering from this form of AA loses all the hair all over the scalp;
Alopecia Universalis – this is an extreme form of AA characterized by the loss of all hair all over the body (eyebrows, eyelashes, nasal hair, etc.). About 1 in 100,000 people suffer from this form of AA.

According to statistics, about 1 in every 250,000 women develop either Alopecia Totalis or Alopecia Universalis.

Traction Alopecia

Traction alopecia

Traction alopecia

Traction Alopecia results from the excessive and prolonged direct insult to the hair caused by specific hair styling techniquessuch as tight dreadlocks, cornrow hairstyles, braids or any other technique  that involves pulling on the roots of the hair.  It is more common among African-Americans, particularly females.  This type of alopecia affects mostly women – hair loss is evident in the frontal temporal area; however, the clinical presentation can vary.

Along with other causes, Trichotillomania (a nervous disorder when a person compulsively pulls out his or her hair) leads to Traction Alopecia and considerable hair loss can result.

Traction Alopecia is a reversible condition but, if left untreated, may progress into Scarring Alopecia.

Scarring (Cicatricial) Alopecia

Scarring alopecia

Scarring alopecia

About 3% of all patients with hair loss suffer from this type of alopecia.  The prevalence of Cicatricial Alopecia in US patients is about 7%.  It occurs in both females and males of all ages.

Cicatricial Alopecia refers to a group of conditions that destroys hair follicles and replaces them with scar tissue.  The causes are poorly understood.  But what scientists do know is the condition involves inflammation (caused by injury or disease) directed at the upper part of the hair follicle where the oil gland and stem cells are located.  This type of alopecia leads to a permanent hair loss.  As a rule, Cicatricial Alopecia develops as small spots of hair loss that may expand over time. Sometimes it develops asymptomatically and, in some cases, can be associated with severe burning, pain and itching.

The Cicatricial Alopecia Research Foundationhas found there is a certain form of Cicatricial Alopecia that occurs mainly in women of African descent known as Central Centrifugal Cicatricial Alopecia (abbreviated as CCCA).  Hair loss begins at the center of the scalp and gradually spreads outward.  The causes of this condition are unknown but researchers suspect genetic factors and inflammation play a part.

Alopecia Neoplastica is another form of Cicatricial Alopecia which results from the direct involvement of the neoplastic process with hair follicles and surrounding skin . The mechanism of this condition is uncertain.  It presents as one or more areas of Scarring Alopecia and has been reported with primary and metastatic tumors.

Alopecia Mucinosa

alopecia-mucinosa

Alopecia mucinosa

Alopecia Mucinosa is a form of localized hair loss sometimes seen in patients with mycosis fungoides. It may occur alone as well. It is rare condition and there is no precise data on the frequency with which it occurs.  It usually presents as slightly scaly bald spots where the follicles are unusually evident.   Alopecia Mucinosa is more common in males between 30 and 40.   The causes are still unknown.

Involutional Alopecia

It is a natural condition occurring as hair begins to thin as one ages and more hair follicles enter the resting phase. Involutional Alopecia is mainly permanent.