The term alopecia is used to describe hair loss. There are several different types and causes of alopecia.

Male Balding

Male Balding: Male pattern hair loss; Androgenetic alopecia

Male balding is the most common type of alopecia. Half of the male population has some degree of balding by the age of fifty and only about 1 in 5 men over the age of seventy keeps a full head of hair. It usually starts as gradual hair thinning on the crown and recession of the hairline. This process may continue to complete loss of hair over the front and top of the scalp leaving a horseshoe pattern of hair remaining around the sides and back of the head.

Hair is produced by structures in the skin known as hair follicles. Normally, a hair on the scalp will grow for a number of years. Eventually the hair stops growing and is shed two or three months later. A new hair then grows in its place. During male balding there is a gradual shortening of the growth period of the hair, so hairs will not grow as long, and a delay in the replacement of the hair after the old hair falls out. Eventually the hair follicles shrink, a process called miniaturisation, so that the hair becomes finer as well as shorter. Finally when the follicle gets too small, no hair grows.

Male balding is caused by hormone reactions and a genetic predisposition. Most balding men, though not all, have a family history of balding. The balding tendency can probably be inherited from either father or mother but at present we have only a limited understanding of the genes that are responsible.

The diagnosis of male balding is made on the overall appearance and pattern of hair loss. Any other types of loss such as in patches, all over loss of hair or rapid progression of hair loss are likely to result from other causes.

For many men, male balding is not a serious problem (though most would prefer to keep their hair!) However, some men are bothered by hair loss and are keen to do something about it. The treatment options include:

• Hair styling, such as clean shaving the head, hair weaving or hair pieces;
• Minoxidil lotion. This will help to slow down or stop hair loss and may produce some new hair growth. It works best when used in early balding - it will not regrow hair on a bald scalp. Treatment must be continued to maintain the benefits. Minoxidil lotion can be bought from pharmacies and is not available on the NHS;
• Finasteride tablets. Finasteride interferes with the effect of male hormones on hair follicles and halts or slows the balding process in over eighty per cent of men. About two thirds of men taking finasteride experience some regrowth of hair. Like minoxidil lotion, finasteride works best in the early stages of balding and the benefits will be lost within a few months if treatment is stopped. This type of drug is not available on the NHS;
• Surgical intervention to transplant hair from the back of the head to the crown of the head or, more radically, flap-surgery in which an area of scalp is transplanted from one area of the head to another.

Female Pattern Hair Loss

Female Pattern Hair Loss: Female androgenetic alopecia

Female pattern hair loss is a common form of hair thinning in women. The changes in hair growth are similar to those in male balding but the pattern of hair loss is usually different and it is very rare for it to progress to true balding. Female pattern hair loss can start at any age from early teens onward. The hair becomes gradually thinner, making it easier to see the scalp. Thinning usually affects the front and top of the scalp but it can be all over the scalp. In most women the frontal hairline does not recede, unlike male balding.

As in men, there can be a genetic predisposition to hair thinning that runs in families. Some women with female pattern hair loss have increased levels of male-type hormones in their bloodstream but most do not and the cause of the hair loss is not yet known.

For women, the cosmetic appearance of their hair is generally more important to their self-esteem than in men, and women are more likely to want treatment. The treatment options include:

• Hair cosmetics, hair styling - a good hairdresser can be helpful;
• Minoxidil lotion. About two thirds of women will get some increase in hair growth with minoxidil lotion. This takes six to twelve months to achieve and treatment has to be continued to maintain the response;
• Drugs that block the action of male-type hormones can help in some women but they are not licensed for treating hair loss. Finasteride is not approved for use in women;
• Hair transplantation can help in selected cases.

Alopecia Areata

Alopecia Areata (AA) is thought to be an autoimmune disorder. In an autoimmune disorder the body's own defence system attacks the body; in the case of AA, it attacks the hair follicles. The exact mechanism in AA has not been identified but it is thought that it can be triggered in a number of ways that include environmental factors, infection, viruses, sunlight or the stress of events such as bereavement or accidents. Genetic predisposition is also thought to play a part as up to twenty per cent of people with AA have a close relative similarly affected. People with AA are slightly more likely than the general population to develop other autoimmune disorders such as Thyroid disorders, Vitiligo or Diabetes Mellitus.

AA can start at any age, including during childhood, and affects males and females of all ethnic groups.

The main feature of AA is the development of one or more bald patches on the scalp about the size of a large coin.

Individuals with AA may also experience any of the following:

• The development of further patches;
• Bald patches on body hair, beard, eyebrows and eyelashes;
• Pitted or ridged nails;
• Rarely, Alopecia Totalis, the loss of all scalp hair;
• Rarely, Alopecia Universalis, the loss of all hair on the body.

In most people the hair grows back but in some cases new patches of hair loss develop before hair grows back on old areas. Sometimes bald patches overlap and merge into larger areas. Almost all people who have a bout of AA will get it again, though episodes of hair loss may be many years apart.

There are several different treatments for AA but none is very effective and none cures the disease. In people who are minimally affected, the hair is likely to regrow on its own and no treatment is needed. In others, treatments such as topical (locally applied) creams, solutions rubbed into the scalp and steroid injections/creams can be used but these have a limited success. For women with extensive AA a wig or hairpiece is often the best option. Wigs tend to be less suitable for men.

Emotional and psychosocial stress can be caused to individuals and the support organisations can be very helpful.

Inheritance patterns
No specific pattern has been identified but AA is likely to appear in more than one member of an affected family.

Additional Information
A NHS leaflet, HC11 - Help with health costs, giving information about prescription of wigs is available at Web: http://www.dh.gov.uk/assetRoot/04/07/80/85/04078085.pdf or can be ordered from Department of Health, PO Box 777, London SE1 6XH Tel: 08701 555455 Fax: 01623 724524.

Other causes of alopecia include:

• Chemotherapy or radiotherapy for cancer;
• Under active thyroid gland (see entry, Thyroid disorders);
• Childbirth. Some women experience excessive hair shedding two to three months after childbirth. This is temporary and recovers fully after a few months in almost all women;
• Increased hair shedding may also occur following various illnesses, especially those associated with a high temperature or rapid weight loss;
• Fungal infections of the skin (mainly in children);
• Some medical drugs;
• Genetic diseases. Hair loss or thinning is a feature of many genetic abnormalities, such as ectodermal dysplasias, although all of these conditions are rare.

Medical text written July 2005 by Contact a Family and Dr A Messenger, Consultant Dermatologist, Royal Hallamshire Hospital, Sheffield, UK.

Further Online Resources
Medical texts in The Contact a Family Directory are designed to give a short, clear description of specific conditions and rare disorders. More extensive information on this condition can be found on a range of reliable, validated web sites and links to them are included in the CD-ROM version of this Directory. Further information on these resources can be found in our Medical Information on the Internet article.

Hairline International - the Alopecia Patients' Society
Lyons Court
1668 High Street
Knowle
Solihull B93 0LY
Tel: 01564 785 980
e-mail: elizst@aol.com
Web: http://www.hairlineinternational.com

The Society is a patient support network, established in 1989. It provides information and support to people who have differing kinds of hair loss including early, total and radical hair loss. Full details of the Society are available (SAE A4 envelope). Hairline International responds to over 2,000 enquiries a year.

Group details last updated September 2007.

Alopecia UK
5 Titchwell Road
London SW18 3LW
Tel: 020 8333 1661
e-mail: info@alopeciaonline.org.uk
Web: http://www.alopeciaonline.org.uk

Alopecia UK provides information, advice and support for people with experience of alopecia areata, totalis and universalis and their families. It is primarily, but not exclusively, website-based. The website receives over 25,000 visits per month and, in addition to information, offers a discussion forum, as well as membership with regular updates, and local support groups.

Group details last confirmed March 2007.