Treating Pruritus in Older Adults
Itchy skin is among the most common conditions in older adults. Here’s what hurts and what helps.
Irritating, itchy skin. We’ve all experienced this condition in various forms. But for older patients, itchy skin—also called pruritus—can be a chronic, uncomfortable condition with various underlying causes that results in a poorer quality of life.
Pruritic skin disease is characterized by the sensation of localized or widespread itchy skin. It’s often accompanied by rashes or lesions and is usually caused by primary skin disease.
Gil Yosipovitch, MD, FAAD, a professor of dermatology at University of Miami School of Medicine and director of the Miami Itch Center, says chronic pruritus in the geriatric population is defined as itch lasting more than six weeks experienced by people 65 years old and older. “It’s common, with a prevalence of 25% to 40%,” he says.
Scratching the itchy areas can cause the inflamed skin cells and nerve endings to release chemical mediators such as proteases that induce itch. And while the physical discomfort can be extremely irritating on its own, pruritus has additional consequences: Older patients may also experience sleep disruption, depression, and anxiety due to the overwhelming frustration of not being able to eradicate the itchy sensation.
According to Tejas B. Patel, MD, a board-certified dermatologist who specializes in medical and cosmetic dermatology, “pruritic skin disease is an ever-increasing concern in the elderly population.”
Causes of Pruritic Skin Disease
Tim Berger, MD, a professor in the University of California, San Francisco School of Medicine department of dermatology, notes that the skin should be examined for evidence of a rash. Pruritic rashes in the elderly include psoriasis, various forms of eczema, and allergic contact dermatitis. Scabies is important to consider, especially in a patient who’s been a resident in or a visitor to a skilled nursing facility. Scabies in older adults may not affect the classic areas of the body such as the wrists, breasts, and waistline and may be very hard to diagnose.
However, in many cases the patient will have no notable skin rash. As Yosipovitch explains, skin conditions common in this population include dry skin, stasis dermatitis on the lower legs and above the ankles (due to venous insufficiency), age-associated alterations in the immune system (immunosenescence) and in diseases such as bullous pemphigoid—an autoimmune blistering disease that’s more common in people older than 70 years. In addition, senescence of the nervous system and subclinical neuropathy such as that which occurs in diabetes can cause itch. The itch in diabetes may precede the abnormalities of blood sugar (prediabetic neuropathy).
Some pruritic conditions actually don’t originate in the skin but are the result of systemic abnormality. That’s why, when evaluating the cause of pruritus, it’s also vital to look at any systemic cause. According to a study by Zirwas and Seraly in the Journal of the American Academy of Dermatology, pruritus can be an important dermatologic clue to the presence of significant underlying disease in 10% to 50% of older adults.1
The systemic causes of pruritus may include end-stage renal disease, liver disease, thyroid disease, and malignancy. In addition, other systemic causes may include iron deficiency and certain conditions that affect the nervous system, such as pinched nerves and shingles. Anxiety can worsen pruritus and complicate its treatment, but should not be the primary diagnosis as a systemic cause of pruritus.
One of the diagnostic challenges associated with pruritus in older adults is the difficulty of examining geriatric skin. As Berger explains, the skin of older patients is often “busy” due to skin changes from lifelong sun exposure and other benign skin growths.
“In addition, the immune alterations of age may modify the appearance of typical skin diseases,” he says. For example, scabies may not itch, may involve the face, and may spare the fingerwebs, all very atypical features for scabies in a younger patient. Laboratory and radiological evaluation may be required to exclude iron deficiency, renal disease, liver disease, diabetic neuropathy, and lymphoma as possible causes.
“A careful medicine history, especially for exposure to calcium channel blockers, may identify a medication as the cause of the pruritus,” Berger says.
According to Patel, diagnosing pruritus can also be time consuming. “This is simply due to the vast number of potential causes of pruritic skin diseases in both the older and younger populations,” Patel says.
As part of the initial diagnosis, identifying pruritic skin disease usually involves a thorough examination of a patient’s skin and detailed questions about their medical histories. It’s important to look for dry, red, rough, scaly, or bumpy skin. Additionally, it’s necessary to ask patients whether they know what inciting factor caused the pruritus and whether they’ve found anything that alleviates the itch. Lab tests (blood, thyroid, liver, and kidney function tests) may be needed to rule out other causes.
“In refractory cases, radiological evaluation may be necessary to exclude this possibility,” Berger says. “Chronically pruritic older adults should have their routine cancer screenings up to date (eg, colonoscopy, mammography). Bullous pemphigoid presents in older adults with pruritus and nonspecific skin eruptions without blisters, so special ELISA [enzyme-linked immunoassay] testing and immunofluorescent skin biopsy testing may also be required to make this diagnosis.”
Treatment of Pruritus
There are two steps to managing pruritic skin disease: First treat the underlying cause, and then treat the itching. According to Berger, treating any underlying cause such as iron deficiency or renal or liver disease may be all that’s required. “While moisturizers are generally recommended for pruritic patients, for the most severely pruritic patients, dry skin is usually not the cause of their pruritus,” Berger says. “Most have an inflammatory dermatosis that requires targeted treatment. This might include immunosuppressives such as methotrexate or mycophenolate.”
Until the skin condition comes under control, geriatric patients also require “itch management.”
First-generation antihistamines may increase risk for falling and mental decline and, therefore, are contraindicated in this population. “Since many agents used to suppress pruritus are relatively contraindicated, caution is needed in choosing an appropriate antipruritic cocktail for an elderly patient,” Berger says. “Most pruritus is mediated by nonhistaminergic sensory neurons. These ‘itch-specific’ nerves do not have histamine receptors, so antihistamines are generally ineffective for pruritus in the elderly.”
“Alternatives include gabapentin and pregabalin (in doses similar to managing pain and neuropathies), low-dose Sinequan (up to 6 mg), and tetrahydrocannabinol (THC, Marinol),” Berger says. “Ultraviolet phototherapy can be an effective treatment for pruritus in the elderly and avoids possible systemic complications. Given the limited number of treatment options, it is critical to continue to try and treat any underlying skin or systemic condition that may be contributing to the pruritus.”
Burnett says treatment should be directed at the underlying cause when present. In the case of xerosis, patients should apply emollients liberally. These typically are most effective after showering. Patients should be encouraged to avoid the use of drying soaps and instead use mild cleansers such as Dove. “Modulating water temperature and avoiding extreme high temperatures while bathing may be helpful,” Burnett says.
“Systemic therapies include antihistamines or doxepin. Narrow-band UVB [type B ultraviolet] phototherapy may also be helpful. If an underlying systemic cause is detected, treatment is often specific to the systemic disease. Since xerosis is particularly common in elderly patients, strategies directed at treating xerosis are often fruitful as first-line attempts.”
Unfortunately, drowsiness is the most common side effect in the majority of the drugs that target the neural system such as sedating antihistamines, GABAergic drugs, and antidepressants. Side effects of treatment of pruritus in older adults need to be constantly monitored, as the geriatric population is more susceptible to the sedative effects of certain medications. Health care providers must keep this in mind when constructing a treatment plan with for older adults.
“Systemic antihistamines and other sedating medications may lead to confusion in elderly patients,” Burnett says. “These should be used cautiously.”
Using a cold compress, ice cubes, or cooling agents containing menthol and camphor also may help relieve pruritus.
Prevention and Management
“Elderly patients also have a propensity to develop allergies to cosmetic products, so they should use fragrance-free products,” Berger says. Preservatives are common allergens affecting this age group, and all topical applications should be free of them. After bathing, older patients should use a fragrance- and preservative-free moisturizer, especially on the lower legs and sides.
“And remember,” Berger says, “neuropathy presenting as pruritus can precede the development of type 2 diabetes (prediabetic neuropathy). Management of metabolic syndrome may reduce the severity of pruritus in the diabetic.”
As dry skin is a common problem in this population and a cause for pruritus, emollients that coat the skin with lipids can reduce the damage to skin barrier and reduce itch. Yosipovitch also advises adding topical anesthetics such as pramoxine to commercial emollients to further reduce the itch. Other compounds that have anti-itch properties are cooling agents such as menthol.
“Being cognizant of the weather can also be very helpful,” Patel says. “The risk for dry and itchy skin increases with high temperatures, low humidity, and frequent hot bathing.” In addition, patients should wear loose, nonirritating clothing and try to keep their environments cool and humidified.
— Maura Keller is a Minneapolis-based writer and editor who writes about health care, business, technology, law, and other topics for regional and national publications.