What is Alopecia? in depth information

'Alopecia' is the word used to describe any type of baldness/hair loss, on the scalp, or of other hairy regions of the body.

The word ‘alopecia’ may be coupled with another word to give a specific meaning. For instance: ‘alopecia areata’ meaning ‘hair loss in areas’.

Most hair loss is not a disease but a perfectly normal process of aging and/or hormone change and put aside by many general practitioners because it is ‘not life threatening’. However, the fine line between normal and excessive loss of hair causes great concern to many, therefore correct diagnosis and care can alleviate worries during phases of patchy hair loss, diffuse shedding and thinning/balding. Psychological effects are far reaching.

Very often the word alopecia is used to describe either, a ‘patchy’ loss of hair, as in alopecia areata, or, a ‘diffuse’ loss of hair, meaning general loss. The two are sometimes seen together and can be related to the same cause or separate conditions.

More often than not, alopecia areata resolves itself. For the cases that do not correct themselves there are therapies. However, applications, injections and electrotherapy can initiate growth but the patient must be aware of the variability of the results, if at all.

Alopecia areata

This cannot be explained before looking at the growth cycle of the human hair follicle. There are different stages or phases of this cycle and these are commonly known as Anagen, growing phase, Catogen, the transitional phase, and Telogen, the resting phase.

Each phase has its period of time and whilst there are a small number of hairs in the resting phase, (approx. 5%) these are the hairs being shed on a daily basis, a few more are in the transitional phase (approx. 8%) and the main mass of our hair (approx. 87%) is in the anagen growing phase which can last from three to ten years. This is variable from country to country; very few adults grow hair to the floor with most populations growing hair to the shoulders or waist. Hair grows at different rates across the head, this tells us that each follicle is a separate unit and can act on its own or collectively, reflecting body changes.

During alopecia areata hairs fall out when they are in the anagen phase of the growth cycle, but the cycle is still on-going, and when the transition or catogen phase starts there is a response, and at this time interestingly the colour pigment production ceases. The telogen, resting phase, as always, allows the hair to fall, but once the anagen phase kicks in it goes no further and the follicle returns to the resting, telogen phase, hence no hair.

This seems to be the reason why the follicle is not destroyed and is ready to grow a hair when the right conditions prevail and allow the cycle to follow a ‘normal’ pattern once again. Although the person suffering from alopecia areata may not think there is anything happening, in the majority of cases, the follicle carries on completing its imperfect cycles until the trigger allows the system to start up the normal cycle again.

Symptoms - The appearance of alopecia areata

The hair loss is in sharply defined areas, usually of the scalp or beard. There can be slight to severe itching, prior to the hair fall, or no irritation at all. For some there are very sore spots before the hair fall with redness and eruption of a pimple. The hair will usually grow back within two to four months showing hairs (maybe white to start with) in the middle of the area and grows outward to fill the patch. It must be said that most people with alopecia areata are in good health and have no other associated diseases.

One of the characteristic signs of AA is the presence of exclamation mark hairs, these are tiny hairs that have broken off, at a weakened point of the hair shaft, and can be seen around the edge of a patch that is still active, meaning hairs still falling.

Alopecia Totalis

This term describes a condition when there is a total loss of scalp hair. However, mechanisms are still in place in the follicle for them to grow whenever the body decides to do so. Hair replacement in the form of a wig or hair piece is suggested until regrowth. Keeping the scalp cleansed and free from flaking/dry skin is necessary as build up of scale must be avoided. Fresh air and sunlight, not in excess, are of prime importance due to the therapeutic nature of both.

Alopecia Universalis

A term used when the hairs across the whole body have been shed. This includes eye lashes, eye brows and fine hairs throughout.

Androgenetic Alopecia or Male Pattern baldness (MPB)

Progressive thinning, giving the appearance of loss of follicles, to temples and crown areas but does not extend to the back and sides of the scalp. If hair is being readily lost then the differences between diffuse loss/patchy loss and MPB must first be identified. Apparently, the absence of 5-alpha reductase keeps the man from developing MPB, and Men with higher levels of 5-alpha reductase and dihydrotestosterone are the men losing their hair.

Treatment: Finasteride can be taken orally available by prescription only. A 5% minoxidil solution can be applied to the scalp, twice daily and hair restoration surgery can be considered that is proving to be very worthwhile for the 40+ patient.

Androgenetic Dependant Alopecia or Female Pattern Loss (ADA)

Progressive thinning with loss of density showing in a triangular shape behind a well defined hair line, forehead to crown. It must be emphasised that most ladies do not lose follicles in the same manner as men the effect is more diffuse loss than balding. Treatment can be sought through an Endocrinologist as ADA can be alleviated by oral anti-androgens and, if indicated, a 2% preparation of minoxidil could be applied. A diffuse loss in addition to ADA must be differentiated and tested accordingly.

Diffuse Loss of Hair

Increased shedding that is noticeable by seeing more hairs in the basin after shampooing and in the brush or comb. Hair can be shed in this way for many reasons and the most well known is after having a baby. It does not happen to all and it does not happen to the same person after each pregnancy. Hairs throughout the pregnancy are held in the anagen phase of the hair growth cycle and the hairs that would have been shed throughout, plus those due to be shed naturally, all fall together within the first few months after the baby has been born. The situation takes time to get back to normal and if there is more excess shedding after six to nine months then it is wise to see the General Practitioner and have both thyroid and ferritin levels (iron) checked.

Telogen effluvium

The term used to describe large numbers of hairs going into the telogen phase and shedding two to four months later in a diffuse manner. TE is referred to as a reflective loss of hair and can be caused by thyroid disorder, low iron, diabetes, medications, and protein deficiency. This is not a definitive list as there are other causes, not least the effects of the sympathetic nervous system described generally as ‘stress’, to do with emotional upset.

Permanent Patchy Loss of Scalp Hair

Hair loss will happen in very small patches that grow very slowly, are hardly noticeable at their onset, but go through periods of time when they progress a little more, and in some cases stop altogether to leave small bald areas that grow no further than the size of a thumb nail. The causes are of unknown origin, although bacterial infection and auto-immune factors have been looked at during research into such cases. The follicles are replaced by scar tissue and different to all of the above conditions. In some cases hair can be transplanted and great success is achieved by scalp reduction for areas of scar tissue.

Information kindly provided by Susan Devenish-Mutton from the Devon Trichology Practice.