THE SKIN is perhaps the largest organ of the body and protects the organism from the hostile external environment. The breakdown of tissues, the impact of air pollution, wind, cold, heat, chemicals, smoke, and cigarette smoke result in skin changes which we associate with ageing.
As we grow older we notice fine lines, wrinkles, variations in the skin colour and a general dullness to the skin. Sun exposure is the single most important factor in this ageing process. To understand the sun's effect, feel the skin on the inside of your arm nearest to your armpit. It is smooth, even toned and firm in contrast to the sun-exposed skin on our outer arm, which is duller, rough and often wrinkled. Our face is the area most exposed to the sun and often shows the greatest degree of photo-ageing.
Ultraviolet (UV) rays damage the skin's collagen and elastic fibres. These fibres are the structural components of the skin and when they are damaged or lost, the skin starts to sag and wrinkles appear. The rough, dry and wrinkled appearance is believed to be caused in part by a deficiency of superficial dermal collagen. Collagen is the major structural protein of the skin and is responsible for adding strength and resilience to the skin. UV radiation contributes to the deficiency by increasing collagen breakdown.
The dermatologist has many options to help in halting or reversing this process:
Education - prevention of photo ageing by the regular use of a sunblock and the avoidance of smoke (your own or another persons) and harsh products. We are fortunate that good sunscreens are in a host of formulations that can be safely used on the face and body. It is also important to treat skin diseases early, especially those that may result in scarring like acne.
Topical treatments - skin smoothing is one of the first signs of improvement in photo-aged skin treated with topical tretinoin (retin-A, Stieva-A). Within weeks of treatment the outer layer of dead cells (stratum corneum) become more compact and ground substances accumulate within the epidermis resulting in more skin turgor and water retention. Visible improvement in wrinkles follows much later (three to four months). There is at that time a corresponding increase in collagen content of the skin. Epidermal melanin (dark spots) is also reduced resulting in decreased mottling.
Microdermabrasion is useful in treating superficial fine lines, wrinkles, photo-damaged skin and skin dyschromias. This procedure uses a machine to throw very fine particles at the skin in a controlled manner. This "sandblasting" of the skin results in a smoother feel.
Repeated superficial peels with glycolic acids may stimulate new collagen growth resulting in increases in skin thickness, less wrinkling and the removal of dark spots. Glycolic acid products may also be used at home to further the treatment, but the over-the-counter products, which contain glycolic acids, are too weak to have any significant effect on their own.
Laser skin resurfacing has emerged over the last decade as a means of restoring youthfulness to the skin. The laser works by removing the outer layer of the skin - the epidermis, causing a wound. This layer regenerates quickly and during the remodelling phase of laser-induced wound healing, normal collagen and elastic fibres replace the old damaged ones. The drawback of this technology is that it may leave darker patches in black skin and so is only suitable for white skin. Newer lasers are on the horizon that may overcome this barrier.
Botox is the fastest growing cosmetic procedure in the United States. This safe injection temporarily paralyses the muscles and results in the smoothing out of large wrinkles such as laugh lines around the eyes and mouth and the frown lines between the eyebrows. The results last only three to six months and require re-treatment.
Dr. Clive Anderson, dermatologist.
