The medical term for hair loss is alopecia. There may be associated scalp disease or scarring. It can affect the scalp or other parts of the body. It may be due to hair shedding, poor-quality hair, or hair thinning. All our hair follicles are formed during fetal growth. Hair follicles are the structures in skin that form hair. We will inevitably notice hair loss of some kind in later life. Hair loss can be an isolated problem or associated with another disease or condition. It can be temporary or permanent, depending on the cause. It can occur in Males and females, Children and adults, People with any color or type of hair.
Hair growth follows a cycle. However, these phases are not synchronized, and any hair may be at a particular phase at random.
The three main phases of the hair cycle are:
- Anagen: Actively growing hair, most of them
- Catagen: In-between phase of 2–3 weeks when growth stops and the follicle shrinks, 1–3% of hairs
- Telogen: Resting phase for 1–4 months, up to 10% of hairs in a normal scalp.
Hair length depends on the duration of anagen. Short hairs (eyelashes, eyebrows, hair on arms and legs) have a short anagen phase of around one month. Anagen lasts up to 6 years or longer in scalp hair.
Hair loss can be due to:
- The decreased growth of the hair: Anagen hair loss
- Increased shedding of the hair: Telogen hair loss
- Conversion of thick terminal hairs to thin vellus hairs; male and female pattern hair loss
- Congenital or acquired hair shaft abnormalities
- An inflammatory skin disease that damages or destroys the hair bulb.
There are many types of hair loss. Alopecia areata, Androgenetic alopecia and Traction alopecia are the most common ones.
Alopecia Areata
The word “areata” means patchy. Because this disease often causes patchy hair loss, it’s usually called alopecia areata. This type of hair loss usually begins in children and young adults, but it can start at any age. People of all skin tones and genders get alopecia areata. Alopecia areata is a disease that happens when the immune system attacks hair follicles and causes hair loss. Where you see hair loss, it means your immune system has attacked hair follicles. Hair loss can appear on any part of your body that grows hair, including your scalp, eyelashes, eyebrows, arms, or legs. Fortunately, this attack rarely destroys hair follicles, so it’s possible to regrow hair.
Symptoms include: Round or oval, smooth bald patch on the scalp, Hair loss on the beard, Spotty hair loss (multiple patches), Widespread hair loss, Loss of eyebrows, Loss of eyelashes, Band of hair loss, Alopecia totalis, Nail changes, Alopecia Universalis, Brittle and crumbling nails
While anyone can develop alopecia areata, dermatologists and other researchers have found that some people have a higher risk. Your risk increases if you have:
- A close blood relative with this type of hair loss
- Psoriasis, thyroid disease, or vitiligo
- Asthma, hay fever, or atopic dermatitis
- Treated cancer with a cancer drug called nivolumab (nye-VOL-you-mab)
- Smoked cigarettes for 10 years or longer and smoke more than five cigarettes a day
Other signs that you may have alopecia areata include:
- Hair starts to regrow on its own where it fell out.
- Hair begins growing in a bald spot and starts falling out in another area.
- Hair loss occurs during a colder month of the year
Treatments include:
- Corticosteroid you apply to the bald spots
- Injections of corticosteroids
- Immunotherapy
Androgenetic Alopecia
Androgenetic Alopecia, also known as male or female pattern hair loss, is a disorder primarily determined by a genetic predisposition for hair follicles to have an excessive response to androgens. This excessive response leads to a progressive shrinking of hair leading to a transformation of terminal hairs to vellus hairs. In males, this hair loss presents primarily on the frontotemporal and vertex regions of the scalp while in women, it presents most commonly with loss in the central, frontal and parietal scalp, which may initially present with a widened frontal hairline. While there may be a psychosocial effect, the primary disorder of androgenetic alopecia is considered benign. The prevalence of the disorder increases with age, affecting nearly 50% of males and 25% of females by age 50. In less common instances, signs of androgenetic alopecia can begin as early as puberty.
Symptoms: Hair thinning or hair loss around your center part, A widening of your center part and hair thinning or hair loss on either side of your part, Hair thinning or hair loss throughout the top of your head.
Cause: It is believed that androgenetic alopecia has both a hormone (andro-) component and a hereditary (-genetic) component to its development. Repeated activation of the androgen receptor on hair follicles leads to shortening of the anagen (growth) phase. This leads to progressive miniaturization of the follicle. Testosterone is able to bind and activate the androgen receptor on hair follicles, but its transformation from testosterone to dihydrotestosterone via the 5 alpha-reductase enzyme allows it to bind to and activate the receptor with a five times greater affinity. The hereditary component is considered polygenic (caused by several genes) in nature. Some of the involved genes include the androgen receptor gene on the X chromosome, the estrogen receptor-β gene and the aromatase gene that converts testosterone to estradiol.
Treatment for males include: Surgical hair transplantation, laser treatments, antiandrogen medications, prostaglandin analogues
Treatment for females include: Oral antiandrogen, surgical hair transplantation, Platelet-rich plasma, Red light therapy
Traction Alopecia
Traction alopecia is a form of hair loss in which mechanical damage to the hair follicle is caused by repeated tension or pulling. Traction alopecia occurs in individuals having hairstyles that produce a continuous pulling force on the hair roots. In time, the continuous pulling can damage your hair follicles. If you damage your hair follicles, your hair cannot grow back, so you develop permanent hair loss.
Hairstyles that constantly pull on your hair include:
- Buns, ponytails, and up-dos that are tightly pulled
- Cornrows
- Dreadlocks
- Hair extensions or weaves
- Tightly braided hair
Symptoms: Broken hairs around your forehead, A receding hairline, Patches of hair loss where your hair is pulled tightly, bumps, redness and tenderness.
Treatment include:
- Limiting or eliminating any hairstyles that pull on the hair and to wear hair in loose styles (especially overnight).
- Reducing the amount of chemicals and heat used during styling is recommended.
- The presence of scalp tenderness, bumps or inflammation may be treated with topical antibiotics or topical corticosteroids.
- For moderate to severe traction alopecia, more aggressive treatments such as oral antibiotics, injected corticosteroids or topical minoxidil may be necessary.
Once scarring is present, hair transplantation may be one of the few available options.
The best treatment of traction alopecia is prevention.
Treatment can help people regrow their hair. Newer treatments are regrowing hair for people who weren’t helped by past treatments.
