Alopecia

Alopecia is loss of hair. It comes in a variety of patterns with a variety of causes although often it is idiopathic.

Each follicle produces a number of hairs during a lifetime. There are 3 phases:

• Anagen or growth phase on the scalp lasts between 3 and 5 years and the hair grows at approximately 1 cm a month. The duration of the anagen phase varies from person to person and it determines how long hair will grow if not cut. Usually about 85% is in anagen phase.
• Catagen phase follows the anagen phase and is an involutional stage that lasts around 2 weeks.
• Telogen or dormant phase lasts about 3 months. The hair remains in the follicle but does not grow.

At the end of the telogen phase the follicle starts production of new anagen hair which displaces the old one from the follicle and the old one is shed. In some animals this is synchronised to produce moults but in humans it is unsynchronised and around 50 to 100 hairs drop out each day, mostly unnoticed. Sometimes people go through a phase of more predominantly telogen phase and they lose a lot of hair in brushes and combs, causing much anxiety, but baldness does not develop.

In all forms of acquired baldness, skin that has previously been protected may be subjected to strong sunlight. Hats should be worn to prevent burning and possibly later malignant change.

• Prevalence varies with cause. Male pattern baldness occurs to some extent in over half of men over the age of 50. It affects women but with a different distribution.
• Alopecia areata has a prevalence of about 0.1 to 0.2% with a lifetime risk of 1.7%. There is no racial or sexual difference in incidence.
• Some forms of cancer therapy almost invariably cause alopecia but hair regrows after treatment is stopped.

It is essential to determine the type of hair loss as this is fundamental to treatment and prognosis.

This condition is of unknown aetiology although there is much support for an autoimmune component. It is commoner in acquired thyroid disease, vitiligo, diabetes and collagen diseases. Stress is sometimes given as a factor but it may be that the disease is the cause rather than the result of stress.¹ There is a tendency to run in families, especially the more severe cases² and it is linked to some HLA antigens.³

The circular pattern of hair loss is characteristic. There are usually smooth round or oval patches with normal skin devoid of hair. Exclamation mark hairs taper towards the proximal end and are said to be pathognomonic but not invariable. Differential diagnosis is with tinea capitis and trichotillomania.

Involvement of nails, usually finger nails, is reported to a variable extent. Clinical Knowledge Summaries suggests a figure of 10 to 30%.⁴ Nail changes may come before or after the alopecia. The commonest lesions are thimble pitting, usually suggestive of psoriasis with psoriatic arthropathy of the local DIP joint. Beau lines are also reported. They usually represent loss of growth during serious illness.

The condition can strike at any age, including in childhood, but the peak incidence is between 15 and 30 years old. There may be a burning sensation or pruritus in some cases. Around 4 patients in 5 have a single lesion, 1 in 8 has 2 lesions and the rest have multiple lesions. There is no correlation between number and severity. Alopecia areata can affect any area although the scalp is the commonest. The beard is affected in about a quarter of men and more rarely eyebrows or extremities may be involved. Loss of 40% of the hair or more occurs in only about 1 in 10. More extensive forms occur in 7%. They are called alopecia totalis if all scalp hair is lost and alopecia universalis if all body hair, including eyebrows, is lost.

Spontaneous recovery can be expected within a few months in minor disease and it is unlikely to be affected by treatment. The prognosis for more extensive lesions affecting at least 50% of the scalp, including alopecia totalis, is less favourable. A large study of more severe disease found that only 1% of children and 10% of adults have prolonged regrowth whilst 44% of children and 34% of adults have a significant period of normal or near-normal hair growth. There is no growth in 22% of children and 34% of adults. The relapse rate over 5 years is 90%.

Traditional wisdom is that no form of treatment is effective and in mild forms, where spontaneous resolution is to be expected, only reassurance should be offered. Nevertheless, if the condition causes distress and no conventional medicine is offered, alternative therapies are likely to be tried and lauded when spontaneous recovery occurs. In more severe cases, where the prognosis is much less favourable, controlled studies have shown some benefit from a number of treatments. However, the overall picture in the literature is of many different types of therapy that have been tried and failed.

• Intralesional steroid injection are first line. They do not invariably work but may produce some improvement for several months. They generally need to be repeated every 4 to 6 weeks.
• Topical steroid creams may work but need to be used for at least 3 months. Skin atrophy and telangiectasia can result and maintenance therapy is required.
• Oral steroids, given long-term are not recommended.
• Various topical immune sensitisers have been tried.⁵
• Psoralen and UVA (PUVA ) treatment is not generally effective.⁶
• Oral ciclosporin is not effective.
• Topical tacrolimus has no effect.⁷
• Minoxidil produces a variable response and is better in a stronger formulation such as 5% solution. It must be used under controlled conditions and does not seem to benefit mild disease. It is helpful in extensive alopecia areata but not alopecia totalis or alopecia universalis.
• Clinical Knowledge Summaries gives some evidence for better results with a combination of topical minoxidill and topical corticosteroids.⁴
• Surgical intervention is ineffective but hair pieces may be acceptable.

Clinical Knowledge Summaries recommend that in those under 16 and if hair loss exceeds 50% of the scalp, referral for specialist help is advised.⁸

Androgenetic alopecia is male pattern baldness. It shows a strong familial trait and tends to affect men from their late teens onwards, becoming progressively more common with advancing age. The 2 patterns are bitemporal recession and a central recession to produce a characteristic horse-shoe shape of remaining hair.

Women also suffer from it to a less obvious extent. There is a diffuse thinning of hair over the crown in the Ludwig pattern. The thinning of hair in women may become rather more pronounced after the menopause when there are fewer oestrogens to counteract the androgens. One author gives the incidence of female alopecia as 13% before the menopause, rising to 75% after age 65. Numbers depend upon definition. Men tend to have baldness whilst women have thinning of hair and preservation of the frontal area. The condition is a matter of end-organ sensitivity to androgens and men who are deficient on their head characteristically have an abundance of hair over the rest of their bodies.

Vertex pattern baldness seems to be a marker for coronary heart disease (CHD), especially in men with hypertension or raised cholesterol.⁹ If a woman presents with male pattern baldness it is worth considering if she has abnormal levels of androgens, especially if hirsute too. Polycystic ovary syndrome (PCOS) gives high levels of androgens. Arrhenoblastoma is an uncommon androgen secreting tumour of the ovary. Testosterone and dihydroepiandrosterone (DHEA) levels should be measured.

Management

This is a very common condition, especially in men, but many find it very embarrassing and adopt various techniques to disguise it. Letting the lateral hair grow and combing it over the bald patch is an old and ineffective ruse. Women may wear wigs. A toupée is a small wig for men that may require an adhesive.

In recent years, two pharmacological agents have become available to treat male pattern baldness. Neither is effective in all cases. Both need long-term administration or there will be recurrence. Both must be prescribed on private prescription. Minoxidil comes in 2% and 5% solution that is applied to the scalp twice daily. The 5% solution is for men only. It may well be months before any improvement is seen and it should be discontinued if there is none after a year. Any improvement will wane after stopping. Finasteride 1 mg tablets are for men only. The dose is 1 mg daily, compared with 5 mg for benign prostatic hyperplasia but it may be up to 6 months before benefit is seen and it reverts on cessation. Minoxidil is successful in about 15% and finasteride in about 60%. The cost is around £25 a month for minoxidil 2%, £30 a month for 5% and around £55 a month for finasteride. Doctors must not quote the price listed in MIMS or the BNF as this is the wholesale cost and does not include a retailer's mark up. These prices are just for rough guidance and will vary greatly according to the pharmacist's profit margin.

Women may use cyproterone, an anti-androgen. It is in the contraceptive Dianette®. Cyproterone and possibly spironolactone merit further investigation.¹⁰ When BMI is high and there are signs of androgen excess as in PCOS, cyproterone is more effective but without signs of androgen excess and with low BMI, minoxidil is better.¹¹

Various surgical techniques of implanting hair have varied success and are also not available on the NHS.

This is when a physiological or hormonal stress triggers many hairs to move into telogen phase. When new hairs appear in anagen phase they push out the telogen hairs and this is between 1 and 6 months, on average 3 months, after the initial insult. This can be an acute or chronic condition but the chronic condition may go unnoticed. The acute condition may be precipitated by a variety of factors:

• Acute febrile illness, severe infection, major surgery and severe trauma.
• Scalp disease in the form of psoriasis and seborrhoeic dermatitis or contact dermatitis of the scalp.
• Chronic illness such as malignancy, particularly lymphoproliferative malignancy, and any chronic debilitating illness, such as systemic lupus erythematosus, end-stage chronic renal failure or liver failure.
• Pregnancy, delivery and stopping hormonal contraceptives.
• Crash dieting, anorexia nervosa, low protein intake, and chronic iron deficiency.
• Heavy metal poisoning including selenium, arsenic and thallium.
• Medications, especially beta-blockers, anticoagulants, retinoids (including excess vitamin A), carbamazepine and immunisations.

Management is the correction of any matters that require attention such as poor diet and reassurance that hair will return in a matter of months.

This is when cancer chemotherapy, immunosuppression or radiotherapy cause rapid hair loss. Doxorubicin and cyclophosphamide are especially notorious but most antimitotics can have this effect. Within a few months of stopping therapy the hair will return but patients undergoing cancer chemotherapy are entitled to free NHS wigs. If the treatment includes hormonal manipulation that may induce hot flushes a wig may be very uncomfortable to wear.

Trichotillomania is a behavioural disorder which can be associated with obsessive-compulsive disorder, but not invariably. In children it is more common in boys, but in adolescence it is more common in girls. Hair loss is asymmetrical and has an unusual shape, with broken hairs across the bald patch which are not easily removed. Single or multiple areas can be affected, including eyebrows and eyelashes. There is minimal or no inflammation.

It may be possible to see that the individual wraps the hair around a finger and pulls on it, perhaps when concentrating on something such as when studying. Management involves behavioural modification.

This is really a form of traction alopecia. Traction alopecia can also occur with hair styles that pull tightly on the hair, usually in girls, and it may lead to frontal recession.

There are a number of other conditions that can lead to loss of hair. Is the bald skin normal? Is there scarring?

• Seborrhoeic dermatitis produces large amounts of dandruff and is often associated with thinning of hair.
• Lichen planus and discoid lupus erythematosis can cause patches of hair loss.
• Tinea capitis, especially animal ringworm, can cause local hair loss, as can impetigo.
• Secondary syphilis causes a typical pattern of hair loss called glades in the wood.
• Check thyroid function as over- or under-activity can affect hair. Check iron status too.

Male pattern baldness is very common now and must always have been over the centuries yet very few portraits or sculptures portray it, presumably because it has always been considered undesirable and the artist had to flatter the subject. The tonsure of the medieval monk was to prevent vanity. The tradition of the celtic church was a pattern rather like frontal baldness, leaving a horse-shoe shape of hair but the more familiar tonsure with the frontal hair preserved was the Roman tradition that was adopted around the turn of the first millennium. In many old pictures the subjects wear hats or some headgear, perhaps to hide a denuded area. From about the time of Elizabeth I to George IV wigs were so common for upper class men and women that one's own hair was an irrelevance.

Victorian times saw the truth of photography but subjects often wore hats. Fashions changed and from the middle of the 20th century other techniques were developed to hide the embarrassment of receding hairlines.

Letting the side hair grow long and combing it over the bald part (the Bobby Charlton formation) was never very convincing, especially for one as active as a football player. Leader of the Opposition was a more sedentary occupation but Neil Kinnock was no more convincing. He complained that a bald man could never become Prime Minister and William Hague and Ian Duncan Smith would agree, although historians will argue for other reasons why they all lost general elections. Our last Prime Minister with typical androgenetic alopecia was Clement Atlee, 1945 to 1951.

Another technique to disguise one's loss is a small hairpiece called a toupée. This was quite popular in the 1970s and 1980s, although they tended to look as convincing as a doormat. Arthur Scargill demonstrated that they did not stay put during scuffles with police on picket lines and so he took to wearing a baseball cap for future confrontations. Elton John renounced many years of never appearing in public without a hat after a hair transplant and the cricketer Graham Gooch even advertises it. An ageing rock star with the coiffure of Kenneth Horne loses credibility.

In recent years many men who are losing their hair have taken to an apparently contradictory but perhaps less maladaptive ruse of shaving off all that remains to be completely bald. Partial baldness is seen as undesirable but, going back many years, film stars like Telly Savalas and Yul Brynner have shown that total alopecia is still compatible with 'looking good'.