Alopecia (hair loss)

Dr Haran Sivapalan

What is alopecia?

Alopecia is the medical term for hair loss. There are many types of alopecia and they can be broadly classified into ‘scarring’ (where scar tissue forms and there is permanent loss of hair) or ‘non-scarring’ (where there is no scar tissue and the hair loss may be reversed).

Hair may be lost from the head and also other areas, including the eyebrows and eyelashes. The pattern and severity of hair loss depends on the type of alopecia. Androgenetic alopecia, more commonly known as ‘male pattern baldness,’ is the most common form of alopecia. Depending on the type of alopecia, there are various treatments available, but their effectiveness varies from person to person.

Types and Causes

There are different types of balding, each with their different causes. Alopecia may be divided into scarring or non-scarring alopecia. Scarring alopecia causes inflammation of the skin with formation of scar tissue. The resultant hair loss is often permanent. By contrast, the hair loss in non-scarring alopecia may be reversible.

Non-scarring alopecia

Androgenetic alopecia (male- and female- pattern balding)

Androgenetic alopecia or ‘male pattern balding’ is the most common type of hair loss. Usually it starts off with a receding hairline. Then there is thinning of the hair around the crown and temples

About 50% of men over the age of 50 have the condition. It can also affect women, with about 50% of women over the age of 65 experiencing androgenetic alopecia (female pattern baldness).

Both hormonal factors and genes cause androgenetic alopecia. Hair follicles convert the hormone testosterone into another hormone – dihydrotestosterone. In the case of androgenetic alopecia hair follicles are too sensitive to dihydrotestosterone. The hair follicles become damaged over time and start to shrink. Eventually the hair follicles completely stop producing hair.

Genes also play a role in androgenetic hair loss. The condition is hereditary, that is, it runs in families. Your family history will give you an indication as to what age you’ll start to lose your hair and what type of balding pattern you will have. The initial signs of androgenetic alopecia in males are often seen in puberty.

 

Alopecia areata  

Alopecia areata is an inflammatory disorder that usually causes small, round patches of hair loss on the scalp. The beard, eyebrows and eyelashes are sometimes affected. In some cases hair can be lost from the whole scalp (alopecia totalis) or whole body and scalp (alopecia universalis).

Some research shows alopecia areata to be an autoimmune disorder, where the body’s immune system attacks its own healthy cells. This damages hair follicles, causing hairs to break off shortly after growth. Alopecia areata is associated with other autoimmune disorders such as hyperthyroidism, diabetes and rheumatoid arthritis.

Alopecia areata also runs in families. One in five people with alopecia areata have a family member also with the condition. Alopecia areata may develop at any age, although it most commonly occurs between the ages of 15 and 29. In the UK, alopecia areata is thought to affect about 15 in every 10,000 people.

 

Telogen effluvium

Telogen effluvium is a common condition that causes more hairs to be shed than normal. This tends leads to thinning of the hair, rather than bald patches. Normal hairs go through a cycle of growth (anagen phase), an intermediate stage (catagen phase) and then start to shed (telogen phase). Telogen effluvium causes an increased proportion of hairs to shift into the telogen phase and be shed. People with the condition may notice increased hairs on combs and brushes after grooming.

The hair loss can occur fairly quickly in response to various triggering factors, including:

  • hormonal changes – such as pregnancy, or stopping hormonal medications
  • psychological stress
  • rapid weight loss or extreme dieting
  • starting a new medication e.g. anticoagulants or beta blockers
  • major surgery

Telogen effluvium may also have longer term underlying causes. These include: thyroid disease, iron-deficiency anaemia, zinc-deficiency and long-term use of some medications.

In many cases of telogen effluvium, hair begins to grow back within six months.

 

Anagen effluvium

Anagen effluvium is hair loss that is caused by the toxic effects of chemotherapy and radiotherapy on the hair follicle. It happens because the hair cycle becomes arrested in the growing stage (anagen phase). This results in immature hairs which are weakened and fall out, while newer hairs may fail to grow.

Not all chemotherapy causes hair loss and the hair will usually grow back fairly quickly when chemotherapy is stopped. With radiotherapy this process may take longer and, in rare cases, it may not grow back at all. This is more common if the doses of radiation are particularly high.

 

Trichotillomania

Trichotillomania is a behavioural condition also known as ‘hair-pulling disorder.” People pick and pluck their hairs, resulting in hair loss. It usually starts in adolescence, but may start earlier than this. Trichotillomania is often associated with anxiety or depression and pulling hair may be a way of temporarily reducing negative feelings.

 

Traction alopecia

This hair loss is caused by pulling on the hair. It can happen with hair extensions, plaiting or pulling the hair into buns too tightly. Once the force on the hair stops, it will grow again.

 

Scarring alopecia

Scarring (or cicatricial) alopecia is hair loss associated with inflammation of skin and the formation of scar tissue. There are several causes of scarring alopecia, most of which are relatively rare.

 

Lichen planopilaris (LPP)

Lichen planus is a non-infectious skin problem that sometimes affects the scalp. It’s called lichen planopilaris (LPP) when it causes scarring of the scalp. It starts with flat, red, eruptions that plug the hair shaft and cause the hair to fall out as the skin starts to scar.  The bald patch is usually smooth and white in the middle but inflamed around the edges.

 

Folliculitis decalvans

Folliculitis decalvans is caused by an over-reaction to a chronic staphylococcal bacterial infection of the hair follicles. It most commonly affects scalp, but can occur in other hair-bearing areas. The follicles become pus filled and inflamed and the hair looks like it’s growing in tufts. This is followed by crusting and scarring and a patch of hair loss.

 

Erosive pustular dermatosis

Erosive pustular dermatosis causes crusting and pustules (pus-filled lumps) on severely sun-damaged areas of the scalp. It generally affects older people and there may often be an underlying skin cancer.

 

Discoid lupus erythematosus

Discoid lupus erythematosus is a rare skin rash that causes scarring on the scalp. The skin is inflamed and scaly and the hair shaft becomes plugged. The condition also causes pigment (colour) changes in the affected skin. The hair loss can be extensive.  It is related to the autoimmune condition systemic lupus erythematosus.

 

Tinea capitis

Tinea capitis is a fungal infection of the hair on the scalp. Though not strictly a hair loss condition, tinea capitis should always be considered when there is a patch of hair loss.

 

The exact symptoms of alopecia depend on the particular cause of the condition. We normally shed between 50 and 100 hairs a day, but people with alopecia shed in excess of this. Generally speaking, signs may include:

  • Noticeable amounts of hair on bedding and clothing
  • Handfuls of hair coming when you run your hands through or brush your hair
  • Visible thinning of the hair in certain spots or all over the scalp

In androgenetic alopecia, the hair slowly starts to thin out at the sides, front and the crown of the head.

In other forms of alopecia, hair may be lost from the beard, eyebrows, eyelashes, limbs and other parts of the body.

Some forms of scarring alopecia may be associated with an itchy rash. Pustules may also form on the skin.

A GP can usually diagnose the type of alopecia from a simple examination of your hair and skin. Further investigations may be required if another underlying condition (e.g. hypothyroidism or systemic lupus erythematosus) is contributing to hair loss.

Referral to a specialist

You may be referred to a dermatologist if your alopecia is not responding to current treatment or if the GP is uncertain of your diagnosis.

Alopecia often does not require medical treatment. Your GP may advise you to watch and wait, as hair loss is often temporary and the hair may grow back. For example, people with alopecia areata may find that their hair grows back within a year. For alopecia associated with an underlying condition (e.g. lichen planus of systemic lupus erythematosus), treating the underlying condition may help to combat hair loss.

Changes in appearance due to alopecia may be a source of psychological distress, so you may want treatment. The treatment options vary depending on the type of alopecia you have. Not all treatments are available on the NHS and they may vary in their effectiveness.

Topical Minoxidil

Minoxidil was originally a drug designed to lower blood pressure, but has also been used to stimulate hair growth in people with androgenetic alopecia (male- and female-pattern baldness). The pharmaceutical mechanism by which Minoxidil causes hair growth is still not clear exactly. It is the only drug treatment available for female-pattern baldness.

Minoxidil comes as either a 2% or 5% lotion, which is usually rubbed into the scalp twice daily. It takes several months before a positive effect is seen. The 5% minoxidil solution may be more effective in promoting hair growth than the 2% solution, but there is an increased risk of scalp irritation. Minoxidil can also increase facial hair growth and cause heart palpitations as side effects.

Hair loss may resume when treatment with minoxidil is stopped, so minoxidil will need to be taken long-term.

Minoxidil is available to buy over the counter at a pharmacy or on private prescription. It is not available on the NHS.

Oral Finasteride

Finasteride (Propecia) belongs to a class of drug known as 5-alpha reductase inhibitors. It works by preventing the conversion of testosterone into dihydrotestosterone (DHT). In androgenetic alopecia, DHT causes hair follicles to shrink and stop producing hair. By reducing the amount of DHT, finasteride therefore acts to prevent shrinking of hair follicles. Studies have shown finasteride to increase the amount of hairs

Finasteride comes in 1mg tablets/capsules and is normally taken daily on a long-term basis. It is first tried for six months and, if effective, continued longer term. Discontinuing treatment causes hair loss to return.

Side-effects of finasteride are uncommon, but some men may experience loss of libido and erectile dysfunction. Finasteride is available on private prescription from your GP only.

Topical corticosteroids

Topical corticosteroids are creams, ointments, foams and lotions containing corticiosteroid drugs and include betamethasone valerate, fluocinolone acetinoide, hydrocortisone butyrate and clobetasone proprionate.

Topical corticosteroids are commonly prescribed for alopecia areata. They work by dampening down the immune system and reducing inflammation. They are applied directly to the scalp and are usually prescribed for a period of 3 months. Side effects of topical corticosteroids include thinning of the skin and worsening of the acne.  They also cannot be applied to the face or beard.

The effectiveness of treatment with topical corticosteroids varies from person to person. It may not successfully produce hair regrowth in some people. In others it may take up to three months before any hair regrowth is seen. Initially hair may appear depigmented or white, before returning to its original colour.

Intralesional corticosteroids

Intralesional corticosteroids are steroid drugs that are injected directly into the skin. They are used alopecia areata and work by dampening down the immune system and reducing inflammation.

Intralesional corticosteroids are particularly useful for small patches of baldness and are prescribed when a person has less than 50% hair loss. They are usually injected every few weeks. In addition to the scalp, they can be injected into other areas, including the eyebrows.

It may take up a month for any hair regrowth to be seen. Discontinuing they injections may cause hair loss to resume. Intralesional corticosteroids

Topical Immunotherapy

Topical immunotherapy involves applying a sensitising agent called diphencyprone (DPCP) to the skin. DPCP causes an allergic reaction on contact with the skin, which gives rise to mild inflammation. In some people, this reaction causes the regrowth of hair. Immunotherapy is thought in to work in autoimmune hair loss (such as alopecia areata) because the allergic reaction in the skin redirects the immune cells away from attacking hair follicles.

Immunotherapy takes place in specialist centres and treatment is usually once a week. The dose of DPCP is gradually increased over the course of treatment.

The effectiveness of topical immunotherapy is mixed. It is thought to cause hair regrowth in less than 50% of people. Hair regrowth can also take longer than 12 weeks. People undergoing immunotherapy will have to wear a hat or similar headwear in the first 24 hours after treatment, in order to avoid exposure to light. In some people, topical immunotherapy may cause severe itching, burning and blistering.

Phototherapy

Phototherapy involves exposing the skin to ultraviolet (UV) light using a special lamp. It is sometimes used for treating alopecia areata. The ultraviolet light helps to reduce inflammation in the skin and hair follicles. Depending on resources, you will probably have to go to a hospital dermatology department to receive this treatment.

There are two types of phototherapy:

  • Narrow Band Ultraviolet B (UVB) phototherapy
  • Psoralen and Ultraviolet A (PUVA) phototherapy

In PUVA (Psoralen and Ultraviolet A), people take a medication called psoralen, before being exposed to the UV light. Psoralen sensitises the skin for treatment with UV light. It can be taken orally or applied to the skin as a cream or by soaking in a bath.

The results of phototherapy in treating alopecia are often poor. Long-term treatment with PUVA is not recommended as it increases the risk of skin cancer. It may also cause itchiness, nausea and a burning sensation in the skin.

Wigs

Wigs may be an option for some people with hair loss. They are available to be purchased on the NHS. There are two main options: synthetic wigs and wigs made from real hair.

Synthetic wigs are made from acrylic. They usually last between 6 and 9 months. The advantage of a synthetic wig is that they are cheaper that wigs made from hair and may require less styling.

Wigs made from real hair may last between 3 and 4 years. They may require more maintenance in terms of styling and cleaning. Real hair wigs are available on to buy on the NHS, but only if you are allergic to acrylic or have a skin condition worsened by acrylic.

Surgical treatments

Surgery for alopecia may be an option for people who have tried medical treatments to no avail. Surgical treatments include hair transplants, scalp reduction and artificial hair implants. These procedures are not usually available on the NHS. People seeking surgical treatment tend to have androgenetic alopecia (male- and female- pattern baldness), although surgery may be used in other types of alopecia.

Hair transplants

This procedure first involves taking a strip (1cm x 30-35cm) of skin from an area on the head that has hair. The strip is then divided into small sections containing one or two hairs. These small sections (hair grafts) are then grafted onto areas of the scalp without the hair. They are placed into small incisions made on the scalp. This ‘strip’ method is called Follicular Unit Transplantation. An alternative is to use a special punch device to remove hairs one by one and then graft these into the scalp. This is called Follicular Unit Extraction.

Both procedures are done under local anaesthetic and sedative. Hair transplants may be needed multiple times at long (9-12 month) intervals, in order to fully regrow hair. Visible hair regrowth normally starts 6 months after the procedure.

Hair transplantation may cause tight, swollen scalp with scabs after the surgery. This should heal with time. As with other surgical procedures, there is a risk of excessive bleeding and infection.

Scalp reduction

Scalp reduction is a procedure to remove hairless skin from the top of the scalp (the crown), and then stitching the hairy parts of the scalp closer together. A procedure called tissue expansion might also be used, whereby a balloon is inflated under the scalp over several weeks to expand the hairy skin. The balloon is then deflated and the excess skin cut away.

The procedure may cause scarring and so is not used for hair loss affecting the front of the scalp. Scalp reduction may be available on the NHS for people with scarring alopecia. It isn’t usually used for androgenetic alopecia.

The procedure carries the risk of bleeding and infection.

Artificial hair implants

Artificial hair implantation involves inserting synthetic hair fibres into the scalp. The procedure is performed under local anaesthetic. There is a risk of infection and scarring and the synthetic hairs may fall out. For these reasons, dermatologists recommend more established treatments for alopecia. Artificial hair implantation is not offered by the NHS.

Hair Cloning / Multiplication

Hair cloning is a new technique that involves extracting hair follicles from healthy, hairy skin and then growing them in a medium. The new hair follicles are then injected directly into the bald skin, where they will eventually grow new hairs. The technique is still new and more studies are needed to thoroughly assess its effectiveness.

Hair loss may be a source of psychological distress. There are various support groups available via the charity Alopecia UK. Your GP will also be able to advise you on sources of emotional support.

Buying a wig can be a difficult decision. Alopecia UK offers advice on how best to choose a wig for your needs.

Alopecia may be the result of other medical conditions, so it is important to ensure any other health conditions are correctly treated.

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Alopecia areata. NICE CKS (2014). Available online at: https://cks.nice.org.uk/alopecia-areata#!topicsummary

Alopecia, androgenetic – male. NICE CKS (2016). Available online at: https://cks.nice.org.uk/alopecia-androgenetic-male#!topicsummary

Alopecia, androgenetic – female. NICE CKS (2016). Available online at: https://cks.nice.org.uk/alopecia-androgenetic-female

Hair loss. NHS Choices (2015). Available online at: http://www.nhs.uk/Conditions/Hair-loss/Pages/Introduction.aspx