Male Pattern Hair Loss Androgenetic Alopecia, Bare

On the bare scalp, indefinite transitional hairs represent the bridge between large, miniaturized end hairs . Traditional MAA models show follicular miniaturization that takes place gradually. This has recently been questioned and it is now believed that the transition from terminal hair to it is taking place as an abrupt and far-reaching process . Either way, the cross-sectional area of the individual hair stems remains constant in the fully developed anagen, indicating that the hair follicles and dermal papilla remain the same size. Therefore, follicular miniaturization takes place between anagenic cycles rather than within the anagen phase. The enzyme 5 alpha reductase plays a central role due to the intrafollicular conversion of testosterone into the most active metabolite DHT .

Progressive replacement of terminal hair by parchment hairs leads to a general decrease in hair density in the affected areas as a precursor to total baldness. The scalp is generally normal and periods of hair growth can be accompanied by a positive hair test. A family history of MAA is seen on both sides of the family in about 80%, while in 20% of cases there is no family history. Telogen effluvium, a type of hair loss, occurs when a large number of follicles on the scalp enter the resting phase of the hair growth cycle called the telogen, but the next growth phase does not begin.

The extension of the kenogen phase, the deceleration phase or the late replacement of telogen hair, appears to take longer in MAA, leaving a higher percentage of empty hair follicles contributing to baldness . In addition, kenogen is extended in MAA, reducing the number of hairs and contributing to the bare process . A higher incidence of benign prostatic hyperplasia has been associated with MAA and MAA may be an early marker of the disease (26-28). However, a recent study suggested that there is no link between androgenetic alopecia, benign prostatic hyperplasia, PSA level and prostate volume .

In women, this type of hair loss is associated with an increased risk of polycystic ovary syndrome . PCOS is characterized by a hormonal imbalance that can lead to irregular periods, acne, excess hair on other parts of the body and weight gain. Topical minoxidil and finasteride can be a useful supplement for hair transplant surgery for MAA. Without adjuvant medical therapy to prevent progression of the bare process, an unnatural appearance can evolve over time. Studies have shown that topical use of minoxidil in the perioperative period can prevent the usual detachment that occurs 1 to 2 weeks after transplantation and accelerate regrowth .

Hair loss from the pattern at the age of 50 affects about half of men and a quarter of women. MAA’s clinical appearance is universal and in most cases instantly recognizable. Hair loss progresses in an orderly manner and is well documented by Hamilton and Norwood . These authors use an adapted classification scale for hair loss in men . The affected hairs are miniaturized and the hair density decreases.

The hair count decreased slightly thereafter, but remained above the original value and remained 5% above the baseline hair count after 5 years of treatment. The decrease in hair count in the finasteride group is significantly lower than that of the placebo group. All things considered, there is a progressive increase in the difference between treatment 防脫髮洗頭水 and the placebo group over time. This demonstrates the effects of finasteride to stimulate a significant amount of hair growth, achieve maximum effectiveness after one year of treatment and then slow the progression of hair loss. At the end of the first year, some were exchanged in the placebo group to get finasteride for the remaining four years.

Hair transplantation includes hair removal from the occipital protuberance and re-implantation in the bare vertex and scalp. With modern techniques, a graft survival of more than 90% can be reliably achieved. A combination of these therapeutic options is now available for men who experience MAA, with potentially beneficial cosmetic results.

Prostate cancer has also been positively associated with MAA in several studies . A meta-analysis performed with Medline and Cochrane databases suggests that an increased risk of prostate cancer was only associated with baldness of the vertex, while other patterns do not appear to have any association . However, associations with high-quality prostate cancer have been found in all MAA patterns, which is especially important in men of years. No clear relationship has been established between cardiovascular disease and MAA. High levels of androgens are believed to cause MAA, as well as atherosclerosis and thrombosis, but some data have shown no association between baldness and established coronary risk factors . An association and pathophysiological mechanism for the relationship between MAA and prostate cancer should also be established, but it may involve double dependence on these dihydrotestosterone conditions .

Both men and women develop this type of hair loss, which is the most common cause of hair loss worldwide. Regardless of whether it develops in a man or a woman, the medical term is androgenic alopecia. A Japanese study shows that finasteride hair growth continues to increase with continuous treatment without significant side effects . Sexual side effects are a major problem in the treatment of male baldness patients with finasteride.