Photoaging Causes and Treatment

Photoaging refers to skin damage caused by prolonged sun exposure, specifically UVA and UVB rays, and can lead to skin cancers. Most of the skin changes that occur as we age are accelerated by sun exposure.

Skin is composed of three layers: the epidermis, the dermis, and subcutaneous tissue. The dermis contains proteins including collagen, elastin, and other important fibers that affect the skin's strength and elasticity, and are responsible for skin's smooth, youthful appearance. UV radiation (UVR) damages these important proteins, leading to photoaging.

Signs and Symptoms

Signs of photoaging can include:

• Wrinkles
• Drooping skin (inelasticity)
• Dark spots ("age spots")
• Broken blood vessels (telangiectasias)
• A yellowish tint to the skin
• Leathery texture to the skin
• Mottled pigmentation
• Easy bruising

Causes

UVR is made up of UVA and UVB rays. In general, UVB rays burn, while UVA rays age the skin, but there is considerable overlap in the damage these rays cause.

UVA rays have longer wavelengths and can deeply penetrate the dermis. The rays damage existing collagen, which causes increased elastin production. Such abnormal amounts of elastin lead to the production of enzymes known as metalloproteinases that repair damaged collagen. However, these enzymes usually end up causing more harm to the collagen than good by incorrectly restoring the skin. As the skin is exposed to UVA rays on a daily basis, this process keeps repeating, resulting in wrinkles and leathery skin.

UVA exposure also causes fine lines and wrinkles around the eyes, mouth, and forehead, as well as age spots, sometimes called liver spots. An age spot is a spot of pigmentation caused by sun exposure. These spots can appear not only on the face but on the rest of the body, including the hands, arms, chest, and back.

Prevention

Visible signs of photoaging can be prevented by following this advice:

• Avoid sun exposure when the sun is strongest, usually between 10 am and 2 pm.
• Sit under umbrellas and in the shade when possible.
• Wear a wide brim hat to protect your face.
• Wear protective clothing, for example, loose-fitting clothes with an SPF factor.

In addition, it's important to apply a sunscreen with an SPF of at least 30 every day that also protects against UVA rays to areas that are exposed to the sun, such as the face, neck, chest, hands, arms, and legs. Daily application of sunscreen can also reduce the risk of developing skin cancer.

In order to find a sunscreen which protects against UVA rays, it's important to not just look at the title on a package but to read the list of ingredients, making sure it contains the specific  ingredients which protect against UVA rays.

Finally, don't forget your eyes. Being out in the sun without sunglasses may accelerate macular degeneration, the leading cause of blindness with age.

Treatments

The gold standard for treating mild to moderate photoaging, is the use of vitamin A products such as retinol and Retin A. Prescription medications (Retin A and Differin) are much more concentrated than over-the-counter formulations and likely to be more effective. These medications were first used for acne and then found to reduce wrinkling, especially fine lines, and facial wrinkles. Retinoids work by increasing cell turnover; it can take a few months of use before you notice a change. Some people develop redness and a rash when a higher concentration product is used, but increasing the dose slowly can often eliminate this reaction.

There are also light-based technologies used to treat photoaging, including:

• Photodynamic therapy is a technique that involves applying a light-sensitizing medicine to the skin. Once the medication has penetrated the skin, the affected area is exposed to a light that activates the medication, promoting collagen growth that gives skin a more youthful, supple appearance.
• Intense pulsed light is a light therapy technique that is effective in diminishing the appearance of uneven pigmentation and broken blood vessels over a series of sessions.
• Laser therapy can treat a variety of skin issues depending on the wavelength of light applied to the skin. Different wavelengths are used for minimizing blood vessels, treating age spots, reducing wrinkles, and removing hair.

The Bottom Line

Keeping your skin young and healthy-looking requires practicing caution in the sun. If you had excess sun exposure in years past, there are treatments to reduce the appearance of age-related skin damage. Finally, remember that sun exposure not only causes wrinkling, but also puts you at higher risk for skin cancer.