The word alopecia comes from the Greek alópex, fox, and indicates a hair loss that occurs in patches. Foxes in particular are known to shed hair in this way during the spring. This term is used to define a process characterised by a decrease in the quality and quantity of hair.
There are various forms of alopecia, which differ in their causes, manifestation, course and treatment. Alopecia can affect the entire scalp or occur only partially. Thus, there are total, diffuse and circumscribed forms of alopecia. The appearance of the scalp can also vary according to the type of alopecia: it can be reddened, normal, affected by desquamation or scarring.
Androgenetic alopecia
Androgenetic alopecia (AGA), also known as common baldness, is a genetically determined condition involving involution of hair follicles and reduction or interruption of hair growth.
In men, it initially manifests itself as a receding of the frontal line and the development of thinning in the vertex area. The follicle units present in the occipital area of the scalp are not affected by the fall. In women, on the other hand, the thinning is diffuse, particularly in the central area of the scalp.
The condition is caused by two main factors:
- The action of androgenic hormones and their relationship to oestrogen
- The presence, in genetically predisposed individuals, of an enzymatic make-up particularly capable of transforming androgenic hormones into stronger hormones that attack hair follicles
A central role is played by the enzyme 5-alpha reductase, which is capable of converting testosterone into dihydrotestosterone (DHT). This hormone attacks hair follicles causing progressive miniaturisation and subsequent hair loss.
What are the causes of common baldness?
In summary, the main causes of common baldness include:
- Genetic causes: hair follicles are only affected by DHT if there is a particular genetic predisposition. The combination of genes responsible for this characteristic has not yet been identified by experts.
- Heritable causes: hair follicles are only affected by DHT if there is a particular genetic predisposition.
- Hereditary causes: there appears to be a family history of the disease. Scientists have identified the X chromosome as the key to transmission. This is why in many cases it is sufficient to look at the hair condition of one’s maternal grandfather in order to imagine the course of baldness in an individual.
- Stress, which is often the main cause of baldness, is also a factor.
- Stress, often mistakenly indicated as a trigger, can actually contribute to increased hair loss, but it is not one of the factors that lead the body to damage hair follicles.
- A poor and unbalanced diet can also cause a general malaise in the body, but does not cause baldness. If this is the cause of the hair loss, it is enough to put the necessary nutrients back into your diet for your hair to regain its strength.
Are there effective drug therapies for common baldness?
It’s impossible to beat genetics. However, there are a number of drugs that can slow down the course of the condition and, in rare cases, reverse it. Here are the main ones:
- Finasteride: a drug that selectively inhibits the enzyme 5-alpha reductase type 2, slowing down the conversion of testosterone into dihydrotestosterone in the tissues
- Minoxidil: topical drug capable of stimulating the anagen phase of the hair, promoting its growth.
Go here for more information on androgenetic alopecia.
Alopecia areata
Alopecia areata is a very common pathology of the scalp manifested by hair loss leading to the formation of completely glabrous and asymptomatic patches, which tend to be oval or circular. Only in rare cases does the skin become erythematous.
The condition may be reversible, but in about 20% of affected patients the hair loss extends to the entire scalp (we talk about total alopecia), while in 1% it also affects body hair, such as eyebrows, eyelashes, armpit hair, leg and arm hair, and pubic hair (universal alopecia).
The disease can occur at any age, but the individuals most at risk are young men and women of prepubescent age and people between 20 and 40 years old.
Alopecia areata does not cause any physical damage, but it has a very strong impact on the psychological sphere of the affected patient, often conditioning the quality of life and undermining self-esteem.
What are the main causes of alopecia areata?
The causes of the condition are not yet fully known to experts. Some of the causes that have been identified to date and that have been proven the most include:
- Immunological factors: it seems that an abnormality in the immune system leads the body to attack hair follicles, causing hair loss
- Chemical and pharmacological factors: some antidepressant drugs have been shown to have, among their side-effects, the ability to cause a sudden form of alopecia areata;
- Seasonality: in the case of relapsing alopecia areata, relapse very often occurs during autumn and winter. Even today there are many studies under way to prove this hypothesis.
- Psychological factors
- Psychological factors: stress is always mentioned among the causes of the pathology. In reality, a condition of psychological discomfort can certainly contribute to a general malaise in the organism, but no real correlations have yet been identified between alopecia areata and psychological factors.
About alopecia areata, it is important to note that it is the cause of the disease.
Is there a cure for alopecia areata?
The difficulties in identifying the causes of the disease make it impossible to define an effective treatment plan against alopecia areata. Topical systemic or intralesional corticosteroids are generally used, but experts are still carrying out trials to identify a suitable and functional treatment for each individual affected.
Go here for more information on alopecia areata.
Fronto-parietal alopecia male
Male fronto-parietal alopecia is manifested by a receding of the fronto-parietal hair line, which leads to the formation of an “M” shape (the so-called hairline). This is a physiological phenomenon that does not progress to the mid-scalp and vertex areas.
Very often this type of alopecia is confused with androgenetic alopecia, as the latter manifests itself in its early stages with a retraction of the hair line. Again, the causes are genetic, but the DNA combinations that lead to hair loss are different.
For further information: Physiological receding or receding hairline.
Traction alopecia
Traction alopecia is a form of alopecia caused by prolonged or repetitive mechanical tension on hair follicles. It is manifested by the formation of areas where hair is broken off or missing. It occurs, in most cases, in the fronto-temporal area, but can occur in any area of the scalp.
The manifestation will depend on the severity of the disease. Initially there is an inflammatory process in the area surrounding the hair follicles. This will gradually become smaller and smaller. Itching is also possible. If the mechanical action continues, real thinning or the formation of alopecic patches may occur.
The condition mainly occurs in women, particularly of African origin, who comb their hair in constrictive hairstyles, such as braids or extensions. Women who tie their hair up in a bun or ponytail are also at risk of developing traction alopecia. Brushing the hair vigorously in the same direction all the time, or wearing a helmet or spectacles frequently, can lead to damage to the follicles in the affected areas and the development of the disease.
How can traction alopecia be treated?
To treat traction alopecia, it is advisable to focus on the cause. If a receding hairline is observed due to a combing pattern damaging the hair follicles, pulling the hair in that manner should be stopped immediately. If the abnormality is in its infancy, it will be possible to reverse the miniaturisation process, whereas if the follicular damage is already severe, it is not possible to encourage new growth. However, taking drugs such as finasteride and minoxidil can help resolve the disease.
For more information: Traction Alopecia
Trichotillomania Alopecia
Trichotillomania alopecia is a type of artificial alopecia which manifests itself as obsessive-compulsive disorder and the need to pull one’s hair out until it is torn off. Contrary to what one might think, it is a very common condition that affects people of all ages from childhood onwards.
It leads to the formation of one or more alopecic areas, generally of irregular shape, where the hair appears at different lengths but is not miniaturized. It affects male and female individuals from childhood onwards.
It must be considered a psychiatric disorder in its own right, associated with anxiety, depression, psychosis, etc., and it is therefore advisable to seek specialist help to resolve the problem.
For more information: Tricotillomania
Seborrheic alopecia
With the term seborrheic alopecia, we indicate a form of early alopecia that generally occurs in men from the age of 20. Seborrhea can also occur in women, but the percentage of cases leading to baldness is lower.
Seborrheic alopecia in men mainly affects the fronto-temporal region and the vertex. Hair loss is caused by excessive production of sebum (seborrhea). The main symptoms include scalp pain, itching, scaling and oily dandruff.
Seborrhea is caused by uncontrolled activity of the sebaceous glands. The reason for this abnormality is a hormonal imbalance. The hormone dihydrotestosterone, which results from the synthesis of testosterone by the enzyme 5-alpha reductase type 2, influences the amount of sebum produced.
The elements that make up sebum, such as cholesterol, free fatty acids, triglycerides, etc., cause an acidification of the pH. This leads to a change in the metabolism and turn-over of the skin cells.
It is hypothesised that a further cause of the condition is the presence of fungus of the genus Malassezia. There seems to be a considerable amount of this fungus in the areas affected by seborrheic alopecia. The fungus causes cell multiplication and the sebum changes in its composition, making the hair very oily. However, a close relationship between this fungus and the condition has not yet been proven.
What are the treatments for seborrheic alopecia?
Trichological therapies against seborrheic alopecia should focus on eliminating excess sebum. Finasteride is the drug generally prescribed by experts.
A useful technology to sanitise the skin and remove any bacteria is the low frequency laser.
Psychogenic alopecia
Stress is often mentioned as one of the factors causing alopecia. For a long time, researchers have been trying to understand whether it can actually be considered a trigger for the condition. As early as the 19th century, Plumbe and Duhring spoke of “post-emotional alopecia”. Research has been ongoing ever since.
There is no doubt that the exogenous environmental, social and psychological stresses and endogenous stresses to which we are constantly subjected in our lives bring modifications to the organism which, trying to adapt, activates defence mechanisms. When our bodies respond to violent emotions and high-stress situations, there is an activation of the hypothalamic-pituitary-cortical axis of the adrenal gland, which leads to a higher than normal hormone release. It is speculated that this may be the reason for excessive hair loss. There is no concrete evidence of this mechanism yet.
What is certain is that the proper functioning of the life cycle of hair follicles and the survival of hair also depend on the well-being of the body. We should try to maintain a state of psychophysical balance so that all the mechanisms of our body can function optimally.
Cychial Alopecia
The term cicatricial alopecia (baldness) refers to irreversible hair loss caused by the destruction of hair follicles due to damage to the stem cells of the hair bulb. All types of cicatricial alopecia, therefore, are the cicatricial outcome of processes leading to the complete destruction of the hair follicle.
Scarring alopecia is generally manifested by the formation of scars in which the hair follicle is replaced by fibrosis or an excess of collagen. The skin appears thin and shiny. There may be a few individual hairs or tufts that continue to grow because the follicle has survived.
Classification of cicatricial alopecia
The classification of scarring alopecia is a matter of controversy in the trichological and dermatological worlds. The same pathology is often referred to by different names and there is much confusion. This is due to the lack of certainty about the histopathology and aetiology of all forms of cicatricial alopecia.
Main types of cicatricial alopecia:
- Lichen Planus
- Folliculitis decalvans
- Discoid lupus erythematosus
- Brocq’s pseudopelade
- Graham-Little syndrome
- Fibrotic Frontal Alopecia
- Scalvarial alopecia in the course of androgenetics
- Erosive pustular dermatosis
- Parvimaculata alopecia
- Keloid acne of the nape of the neck
- Desiccant cellulitis
Pityrian alopecia (dandruff alopecia)
Pityrian alopecia is caused by dandruff, which, if left untreated, can lead to a thickening of the scalp and subsequent damage to the hair bulb.
Dandruff, or pityriasis, generally occurs between the ages of 10 and 25 and tends to improve with age, although in some cases it persists throughout an individual’s life. It is caused by an excessively rapid turnover of the cells that make up the epidermis, the uppermost layer of the skin. These tend to detach before they have fully matured and give rise to white scales made up of clusters of cells from the stratum corneum. The phenomenon may be limited or extend to the entire scalp.
The reasons for this phenomenon are still unknown to experts. It is thought that the digestive system and the liver are involved, but also that androgenic hormones regulate the process. The fungus Pityrosporum ovale is also always present in large numbers in dandruff scales, but it is not clear whether the dandruff is a hospitable environment for the fungus to settle or whether it is a trigger.
How do you treat alopecia dandruff?
The market offers dozens of anti-dandruff shampoos and lotions, capable of fighting germs and micro-organisms and removing dead cells from the scalp. However, the risk of using these products is that the stratum corneum will become thinner and seborrhoea will increase.
It is essential to consult a trichologist to find out which treatment is best for each individual case.
Actinic alopecia (radiation alopecia)
This is a rare form of alopecia that occurs after excessive exposure to radiation (ultraviolet rays and x-rays) to the skull. Actinic alopecia is due to the action of the radiation beam on the scalp. Spots are observed in some cases and the hair becomes very weak and falls out very easily.
In almost all cases, it is reversible and tends to resolve spontaneously after several months.
Senile alopecia
Our hair, like our skin and our organism in general, is subject to the ageing process, which leads to progressive weakening. Senile alopecia is a clear example of this concept. The fact that hair falls out with age is entirely physiological. It is a natural phenomenon that should not cause any concern.
The life cycle of the hair follicle, and the subsequent growth of hair, changes with age. The mechanisms are not yet fully understood by experts. There seems to be an imbalance between the activation signals and the inhibition processes of the stem cells of the hair follicle. This imbalance leads to a slowdown in cell regeneration. A particular protein, follistatin, is capable of modifying the metabolic processes of the cells.
Iatrogenic alopecia (drug-induced alopecia)
Iatrogenic alopecia (baldness) is caused by taking certain drugs that act on hair follicles and inhibit hair growth. The best known example is alopecia caused by chemotherapy drugs, but it is also worth mentioning:
- Anticoagulants (e.g. heparin)
- ACE inhibitors
- Antigotics
- Antimalarials
- Antineoplastics
- Anthyreumatics
- Beetablockers
- Thyroid Drugs
- Neuroactive drugs
- Velenes
- Oral contraceptives, testosterone and anabolic steroids (hormonal drugs);
- Hormonal drugs
- Penicillin
Hair loss can occur in anagen or telogen. Alopecia in anagen appears as early as 10 days after taking the drug, those in telogen after 90-100 days.
