Androgenic Alopecia

Androgenic Alopecia (also known as male pattern baldness) is the most common cause of hair loss, both male and female.

In classic pattern baldness, hair is lost in a pattern, beginning above both temples.  Hair also thins at the crown of the head. Often a rim of hair around the sides and rear of the head is left.

The Cause

A variety of genetic (and possibly environmental) factors likely play a role in androgenic alopecia.

Researchers have determined that pattern hair loss is related to hormones called androgens, particularly an androgen called dihydrotesterone (DHT).

Male pattern baldness is caused by a genetic sensitivity of hair follicles to DHT, which causes them to shrink or "miniaturize". This shortens their lifespan and prevents them from producing hair normally.

There are also theories that the scalp tightness and resulting baldness may be a result of co-contraction of muscles in the head, leading to increased tension.

Hormone levels correlated with androgenic alopecia

Men with androgenic alopecia typically have higher levels of 5-alpha-reductase, lower levels of total testosterone, higher levels of unbound/free testosterone, and higher levels of total free androgens including DHT.

5-alpha-reductase is responsible for converting free testosterone into DHT.

Hair loss and lifestyle

While genetic factors seem to play the principal role in the development and progression of androgenic alopecia, lifestyle also plays a role as demonstrated by the vast increase in male pattern baldness.

Diagnosis

The diagnosis of androgenic alopecia can be usually established based on clinical presentation in men.

In most cases androgenic alopecia may be confirmed by a microscopic scalp analysis.

Treatments

Regrowth of lost hair in the early stages of male pattern baldness can be fully restored with non-invasive treatments such as laser, however, bald spots, where hair follicles have closed down and been destroyed, cannot be restored with non-invasive treatments and require a hair transplant to achieve coverage.