Dry skin and the elderly
Elderly people constitute 25 percent of my patients. And xerosis (dry skin) is their most common problem. Xerosis is a multifactorial process that occurs in the epidermis (the skin’s first layer). It is characterized by itchy, dry, cracked and fissured skin. Dry skin may be diagnosed as xerosis, eczema craquelé or asteatotic eczema. Most often this is accompanied by severe itchiness.
A strong, well-functioning lipid barrier is the foundation of healthy, glowing skin.
In xerosis, the problem lies in impaired lipid barrier function and an abnormal skin cell maturation process in the stratum corneum, the outermost layer of the epidermis, and consists of layers of dead skin cells, while the lipids (the skin’s natural fats) are likened to a brick wall where the corneocytes act as bricks, and the lipids act as the cement that keeps these bricks together.
This structure essentially keeps the water within our bodies inside and prevents trans-epidermal water loss, when water passes through the dermis to the epidermis and evaporates from the skin’s surface, while shielding us against external environmental stressors, microorganisms like bacteria and allergens.
As humidity increases the proliferation of the epidermis, it may disrupt the normal skin cells’ maturation process. This leads to retained skin cells in the outer layers of the stratum corneum, causing scaling and flaking.
In normal skin, the lipid barrier is arranged in a bilayer with fairly consistent proportions of lipids: 50 percent ceramides, 25 percent sterol esters, and 15 percent fatty acids. It has been shown that with xerosis, there is a disruption of the bilayer, and skewed ratios of the lipid components.
Moreover, aging decreases lipid biosynthesis in the epidermis, and aged skin has lower water content than younger skin.
There is a natural moisturizing factor (NMF) present in the skin that is the end product of profilaggrin (a protein) synthesis, which is decreased in xerosis. Also, the chain of events from profilaggrin synthesis to the presence of NMF can be disturbed by ultraviolet light, low humidity, and soaps.
As humidity increases the proliferation of the epidermis, it may disrupt the normal skin cells’ maturation process. This leads to retained skin cells in the outer layers of the stratum corneum, causing scaling and flaking.
Another end product of profillagrin is filaggrin, a type of protein found in the skin, the mutation of which can interfere with the skin’s ability to act as a barrier. This allows water to be lost from the skin, and allows bacteria and other substances to enter. This could possibly lead to allergies, irritation and infection.
Pruritus or itching results from the release of histamine and other biological mediators such as serotonin, substance P, kinins, prostaglandins, neuronal relays — including neurotransmitter receptors and nerve endings — and psychogenic components from a trigger.
It has been postulated that the loss of the water barrier triggers a release of inflammatory cytokines in the epidermis, leading to the migration of inflammatory cells to the skin and the rupture of cells, leading to the release of histamines and proteases that initiate cellular damage and can stimulate nerve endings, resulting in itching and pain.
Other theories involve an increased penetration of antigens through the altered stratum corneum. These antigens cause the release of chemical mediators such as histamine.
Use gentle cleansers without any dyes, fragrances, or alcohol. Avoid over- cleansing with harsh soaps.
Due to the high prevalence of comorbid diseases such as diabetes, hypertension, hyperlipidemia and others, elderly patients often take multiple prescription medications, as well as non-prescription vitamin and herbal supplements, making it hard for a dermatologist to identify the possible trigger. So it’s best to inform your derma what kind of medications you are taking.
Systemic diseases like chronic renal failure and liver insufficiency also contribute to xerosis and pruritus. Iron deficiency anemia can also produce severe pruritus by promoting either epithelial or neurologic dysfunction.
Xerosis can also be related to other malignancies like common tumors of the lung, colon, breast, stomach, prostrate cancer, polycythemia vera, connective tissue disease (dermatomyositis and scleroderma) and even HIV infection.
Knowing this, additional diagnosis of these problems should be explored. In addition, medications should be reviewed for agents that promote dry skin such as diuretics, lipid-lowering agents, anti-androgens, oral contraceptives, cimetidine, anti-hypertensives. antibiotics and anti-cancer drugs.
These measures may also be helpful to patients with xerosis:
- Avoid bath or shower water that is too hot. Opt for lukewarm water.
- Avoid excessive water exposure, and do not spend extended amounts of time in a hot tub or pool. So take shorter baths or showers and avoid bathing too frequently.
- Use gentle cleansers without any dyes, fragrances, or alcohol. Avoid over- cleansing with harsh soaps.
- Pat the skin dry after a shower with a towel instead of rubbing the towel on your body. So avoid vigorous towel drying.
- Stay hydrated by drinking plenty of water.
- Limit the use of soap on dry areas of skin and choose mild soaps with oil added.
- Avoid scratching the affected area.
- Use oil-based moisturizing lotions frequently, especially in the winter, and directly following a bath or shower.
- Use a sunscreen when going outdoors.
- Avoid extended sun exposure.
- Use a humidifier to increase the moisture of the air in your home.
- As much as possible, avoid places with very cold, dry winters. If you can’t, use central heating in the home or the workplace.
