Hair loss or androgenetic alopecia

What you should know:

1. Androgenetic alopecia is a common disorder leading to hair loss; it is genetic or hereditary in origin. Hair falls out because the hair follicles or roots are too sensitive to male hormones circulating in the blood; the hair on the crown of the head is protected from the effects of these hormones.

2. Up to two-thirds of Caucasian men between the ages of 35 and 40 are affected; women are affected to a lesser degree (around 30 % before menopause).

3. In men, the first sign of baldness is a gradually receding hairline followed by more or less extensive loss of hair around a bald patch on the crown. In women, hair loss appears as a gradual and diffuse reduction in hair density all over the scalp; the hairline is usually not particularly affected.

4. Generally, if hair loss begins early in life, it will be more severe in later years than if it appears when a person is older.

5. It is normal for the hairline to recede a little at puberty; 96% of boys and 80% of girls are affected by this phenomenon.

6. If one parent is bald, about half the offspring will carry the dominant gene for baldness.

7. In general, hair loss is gradual, with alternating active periods and periods of remission.

   • There are several forms of alopecia about which a specialist should be consulted, including:
   • Alopecia areata, an auto-immune disease, which causes hair loss in irregular patches;
   • Alopecia totalis, an extreme form of alopecia areata, which affects the entire scalp;
   • Alopecia universalis, which affects the entire body;
   • Traction alopecia, which is caused by too much pulling (for example, by a ponytail that is too tight);
   • Telogen effluvium, which is usually temporary and reversible and is caused by intense physical or emotional stress, certain drugs and thyroid abnormalities;
   • Anagen effluvium, which results from taking certain medications, such as chemotherapeutic drugs.

8. The table below illustrates Dr. O’tar Norwood’s classification of the different stages of hair loss.