What is xerosis, particularly in an elderly patient?

What is Xerosis?

Xerosis is dry skin characterized by pruritic (itchy), dry, cracked, and fissured skin that results from reduced water content in the stratum corneum below the 10-15% threshold needed to maintain skin suppleness and barrier integrity. 1, 2

Pathophysiology

Xerosis develops through multiple mechanisms that compromise skin barrier function:

• Intrinsic aging changes include decreased keratinization efficiency and reduced lipid content in the stratum corneum, which impairs the skin's ability to retain water 1
• Water content disruption occurs when skin falls below the critical 10-15% water threshold, with both "static" (bound) and "dynamic" water components becoming depleted 2
• Lipid barrier dysfunction results from damage to intercorneocyte lipid structures, which normally regulate skin humidity through their hydrophobic properties 2

Clinical Presentation in Elderly Patients

Xerosis manifests with distinct features that worsen with age:

• Primary symptoms include visible dryness, scaling, cracking, and fissuring of the skin surface 3
• Pruritus (itching) is a hallmark symptom that drives the scratch-itch cycle, leading to excoriations and increased infection risk 1, 3
• Distribution patterns show xerosis most commonly affects the lower limbs, though it can occur on any body area 4
• Severity classification ranges from mild surface dryness to severe eczema craquelé (also called asteatotic eczema), where the skin develops a "cracked porcelain" appearance 3

Epidemiology in the Elderly

The burden of xerosis increases substantially with age:

• Prevalence reaches 53% (95% CI: 36-69%) in older adults overall, with highest rates in nursing home residents 4
• Gender distribution shows similar prevalence between males and females 4
• Geographic variation demonstrates higher prevalence in developed countries, likely related to environmental factors like indoor heating and air conditioning 4

Contributing Factors in Elderly Patients

Multiple extrinsic and intrinsic factors converge to cause xerosis in older adults:

• Medications including diuretics and similar agents that affect fluid balance contribute significantly 1
• Environmental factors such as overuse of heaters or air conditioners reduce ambient humidity and strip skin moisture 1
• Bathing practices involving hot water, harsh soaps, and excessive frequency remove protective lipids from the skin surface 1
• Chronic diseases affecting organ systems can manifest with xerosis as a cutaneous sign 2

Clinical Significance and Complications

Xerosis is not merely a cosmetic concern but carries real morbidity:

• Quality of life impact is substantial due to associated stigma, constant pruritus, and functional limitations 5
• Infection risk increases when scratching creates excoriations that breach the skin barrier 1
• Progression risk to stasis dermatitis and ulcer formation occurs if xerosis remains untreated, particularly in the lower extremities 3
• Inflammatory cascade can develop when chronic xerosis triggers eczematous changes requiring more intensive treatment 3

Differential Diagnosis Considerations

When evaluating xerosis in elderly patients, exclude other conditions:

• Uraemic pruritus must be considered, as dry skin (xerosis) is the most common cutaneous sign in dialysis patients, though it does not necessarily correlate with pruritus intensity 6
• Atopic dermatitis includes xerosis as a notable clinical finding but occurs with additional features like erythema, edema, and lichenification 6
• Contact dermatitis, eczema, and seborrheic dermatitis can present with similar symptoms and may coexist with xerosis 7

Management Principles

Treatment focuses on restoring barrier function and preventing complications:

• Emollient therapy with barrier-restoring ceramide-containing moisturizers is essential, as these restore damaged intercorneocyte lipid structures and increase water content 5, 2
• Environmental modification includes increasing ambient humidity and avoiding excessive heating or air conditioning 1
• Bathing technique changes involve using lukewarm water, limiting bath duration, and switching to gentle cleansers that preserve skin lipids 1, 5
• Avoidance of sensitizers such as lanolin, aloe vera, and parabens is critical, as these commonly found emollient ingredients can trigger delayed hypersensitivity reactions in elderly skin 1
• Regular application of humectant-containing leave-on skin care products within structured regimens significantly alleviates xerosis 4

Common Pitfalls

Several management errors should be avoided:

• Underutilization of moisturizers is common despite their proven efficacy, with many patients with mature xerosis failing to use available products consistently 5
• Sedating antihistamines should be avoided in elderly patients due to cognitive impairment risk, even though pruritus is prominent 7
• Long-term topical steroids cause skin atrophy and should be avoided for simple xerosis management 7