Aging and photoaging - Dermatology and aesthetics


Dermatology and aesthetics

Dermatology and aesthetics

Aging and photoaging

The skin ages
  • The skin ages

The skin ages

Skin aging is an unstoppable process, sometimes reversible but always inevitable, during which physiological or structural changes occur in all organs. With the passage of time, the structures of our organism undergo a phenomenon of senescence. While the internal organs, however, age according to biological laws apparently independent from sun exposure, the skin undergoes an "additional" aging mainly induced by chronic exposure to ultraviolet radiation. The integumentary system therefore constitutes, given its more external and exposed location, the organ in which the signs of aging generally understood appear first. On the other hand, the dermatologist is used more and more often not only in cases where the aging process is manifested by skin diseases that alter the external appearance, but also when the main effect consists in aesthetic damage. The aging of our skin and our appendages (hair, hair, nails, etc.) has therefore become the main topic of the new dermatocosmetology, which is essentially based on the prevention of the myth of tanning (tanning obtained with the sun exposure to the sea or to the mountains or through special equipment), typical of the wellness society and the origin of premature skin aging.

Skin aging is classically divided into two categories: chrono-aging or intrinsic aging (aging); photoaging or photoinduced aging (photoaging).

The first type includes the set of genetically programmed (morphological and functional) modifications that occur on the skin and are due to endogenous factors that affect both the areas protected by ultraviolet rays and those exposed to light; the second type, however, is due to the cumulative effect of solar radiation which overlaps and amplifies the natural process. These two distinct types have long been confused with each other, because photo-aging, from a clinical point of view, surprisingly simulates chrono-aging and because in the photo-exposed areas the two phenomena tend to overlap and amplify synergistically. Currently, however, it is preferred to consider photoaging as specific UV damage to the skin cells and, as such, partially reversible.

Natural, intrinsic or chrono-induced aging occurs with some structural and clinical modifications affecting the entire skin area. Physiologically there is a reduced epidermal exchange and a thinning of the dermis: the skin becomes dry, takes on a "parchment" appearance and allows the superficial vascular circulation to transpire; moreover the degradation of elastic fibers, the alteration of collagen fibers and the decrease of hyaluronic acid make it elastic, loose and furrowed by wrinkles.

In the photoexposed areas there are sometimes whitish atrophic scars, telangiectasias and frequently dyskeratotic lesions, sometimes evolutionary. There is also a decrease in the production of sebum and sweat and an alteration of the skin appendages, with a decrease in hair and hair, as well as nail fragility sometimes associated with evident deformations.

From a global point of view, the biological system loses to some extent the ability to respond to exogenous and endogenous stresses, be they due to physical, biological or chemical agents; aging of the immune system is thus associated with a higher incidence of pathogens (infections). The aging process makes the skin more sensitive also to irritative stimuli of any kind, facilitating the onset of irritative or allergic dermatitis and, in some cases, of bullous lesions; Finally, the reduction of vascularization justifies the tendency towards hypothermia of older people.

In photoaging, i.e. aging caused by chronic exposure to sunlight, ultraviolet (UV) rays interfere with the skin, promoting biological events that result in a series of damages, both acute (erythema and pigmentation) and chronic. These damages establish a broad symptomatic complex which is observed on photo-exposed skin of elderly subjects, especially after years of exposure to solar radiation. The severity of photoaging also depends on the duration and intensity of the exposure, the individual phototype and the geographical latitude.

The main manifestations consist in alterations of the skin texture with an accentuation of expression lines and the formation of wide furrows, in alterations of the consistency with skin thickening, roughness, xerosis and elastosis, in changes in pigmentation (solar freckles, dyschromia) and skin vascularization (telangiectasias), also in the appearance of pseudocycators and actinic keratoses; the latter are tumor lesions which constitute a sort of final moment of the evolutionary path typical of photoaging.

Man has always associated the concept of beauty, health and happiness with youth, and the appearance of the skin, in particular, consciously or unconsciously stimulates a judgment on the patient's state of health and age. This concept justifies the use of cosmetics and cosmeceuticals or the use of laborious surgical interventions in order to slow down, limit or mask the signs of skin aging.

Dermatology, in recent years, is thus acquiring a dermo-aesthetic imprint that leads it to focus on the execution of increasingly less invasive interventions aimed at allowing a measurable improvement in self-esteem and quality of life, understood as psycho-physical well-being, and therefore often to minimize those manifestations of aging considered true aesthetic defects.

Certainly, in the increased use of these interventions, an overall conception of life typical of the society of well-being affects, for which youth is a measure of value, while aging is the moment of decline: the great challenge then becomes that of giving " life to the years ”, in consideration of the lengthening of the average age, improving the quality of existence and ensuring health and psychophysical integrity to overcome the natural stages of life without problems. This challenge includes the need to always find new anti-aging treatments to eliminate skin alterations (mainly induced by photo damage), for example by replacing damaged skin with renewed skin or through treatments that promote cell differentiation capable of reversing the modifications induced by chronic UV exposure.

The wide range of programmable and implementable treatments to deal with skin signs caused by skin photoaging must not, however, make us forget the preventive efficacy of daily hygiene-cosmetic standards such as cleansing, hydration (a fundamental parameter for all plasto-elastic characteristics skin) and especially photoprotection (both topical and systemic), as well as the importance of adequate nutrition and balanced physical activity.

Go back to the menu