106: Skin Aging Flashcards
What is the role of oxidative damage in the aging process of the skin?
Oxidative damage leads to the upregulation of stress-related factors, triggering downstream events that enable the aging process. This includes the activation of hypoxia-inducible factors and nuclear factor kB, which promote the expression of pro-inflammatory cytokines such as IL-1, IL-6, VEGF, and TNF-alpha.
What are the intrinsic factors that contribute to skin aging?
Intrinsic skin aging refers to the unavoidable physiological changes influenced by genetic and hormonal factors. Key changes include decreased collagen production, reduced blood flow, lowered amounts of lipids, and loss of rete ridges.
How does extrinsic aging differ from intrinsic aging of the skin?
Extrinsic aging is caused by environmental factors, primarily UV radiation, leading to physiological and histological changes in the skin. Intrinsic aging is due to genetics and hormones.
What are the typical features of photoaging caused by UV radiation?
Photoaging results in deep wrinkles, skin laxity, coarseness, increased fragility, multiple telangiectases, and darker skin with mottled pigmentation.
What is the significance of telomere modification in the context of oxidative stress and aging?
Oxidative stress modifies telomeres, leading to cellular senescence or apoptosis when they reach a critically short threshold.
What is the effect of oxidative damage on cellular proteins?
It leads to the accumulation of damaged proteins that interfere with normal cellular function.
What is intrinsic skin aging?
It refers to the unavoidable physiologic changes of the skin influenced by genetic and hormonal factors.
What are some changes associated with intrinsic skin aging?
Decreased collagen production, reduced blood flow, lowered amounts of lipids, and loss of rete ridges.
What is the most powerful source of extrinsic aging?
UV radiation.
What is photoaging?
UV radiation-mediated structural and functional changes of the skin.
What are some exogenous factors contributing to extrinsic skin aging?
Cigarette smoking, diet, chemical exposure, trauma, and air pollutants.
How does extrinsic skin aging differ from intrinsic skin aging in terms of intervention?
Extrinsic skin aging is more amenable to intervention and preventive measures.
Why is extrinsic skin aging considered more amenable to intervention compared to intrinsic aging?
Extrinsic skin aging is primarily caused by environmental factors, which can be modified through preventive measures.
A 65-year-old patient presents with dry, pale skin and fine wrinkles. What intrinsic factors contribute to these changes?
Intrinsic skin aging is influenced by genetic and hormonal factors, leading to decreased collagen production, reduced blood flow, lowered lipid amounts, and loss of rete ridges.
What percentage of UV radiation that reaches the earth’s surface is UVA and what is its significance in skin aging?
More than 95% of UV radiation that reaches the earth’s surface is UVA, which penetrates to the lower dermis and is considered a larger contributor to skin aging.
What are the effects of UVB radiation on the skin?
UVB radiation only penetrates into the epidermis and upper dermis, serving as a chief source of direct DNA damage, inflammation, and immunosuppression.
How does UV damage affect collagen in the skin?
UV damage impacts collagen degradation and synthesis, leading to the production of elastotic material in the skin.
What is the relationship between photo-damaged skin and mitochondrial DNA mutations?
Photo-damaged skin is associated with a higher frequency of mitochondrial DNA mutations that result in decreased mitochondrial function and generation of reactive oxygen species (ROS).
What changes occur in the epidermis between the third and eighth decades of life?
The epidermal turnover rate decreases by 30-50%, coinciding with deterioration of wound repair capacity and overall thinning of unexposed epidermis by 10-50%.
What is the most pronounced histologic change observed in aged skin?
The most pronounced and consistent histologic change of aged skin is the flattening of the dermal-epidermal junction (DEJ) and loss of rete ridges.
How does estrogen affect skin aging post-menopause?
After menopause, levels of estradiol drop, leading to rapid onset of skin aging characterized by decreased collagen content, thinner skin, reduced elasticity, dryness, and increased wrinkling.
What impact does aging have on the permeability of the stratum corneum?
Aged skin has altered drug permeability with reduced absorption of hydrophilic substances, and there is an impaired barrier partly due to a decline in stratum corneum lipids.
What percentage of UV radiation that reaches the Earth’s surface is UVA?
More than 95%.
What is the primary effect of UVB radiation on the skin?
It is a chief source of direct DNA damage, inflammation, and immunosuppression.
What happens to the basement membrane following UV radiation exposure?
It becomes multilayered and partially disrupted.
What is the role of estrogen receptor signaling in skin aging?
It is a critical modulator of redox balance and oxidative stress.
What skin changes occur after menopause due to decreased estrogen levels?
Decreased collagen content, thinner skin, reduced elasticity, dryness, and increased wrinkling.
What happens to the epidermal turnover rate between the third and eighth decades of life?
It decreases by 30-50%.
What is the most pronounced histologic change in aged skin?
Flattening of the DEJ and loss of rete ridges.
How does aged skin’s stratum corneum change with age?
It has greater susceptibility to irritant contact dermatitis and severe xerosis.
What happens to drug permeability in aged skin?
There is altered drug permeability with reduced absorption of hydrophilic substances.
What decline contributes to impaired barrier function in intrinsically aged skin?
Decline of stratum corneum lipids.
What age-related change occurs in epidermal filaggrin levels?
There is a decrease in epidermal filaggrin.
What are the primary differences in the effects of UVA and UVB radiation on skin aging?
UVA penetrates to the lower dermis and is a larger contributor to skin aging, while UVB primarily causes direct DNA damage, inflammation, and immunosuppression.
A postmenopausal woman complains of rapid skin aging. What hormonal changes are likely responsible?
Postmenopausal skin aging is associated with decreased estradiol levels.
A patient with photodamaged skin has a multilayered and partially disrupted basement membrane. What is the likely cause?
The likely cause is UV radiation exposure.
A patient with photodamaged skin has increased ROS generation. What is the impact of visible light on this process?
Visible light generates ROS in the skin, leading to the formation of oxidized DNA bases and increased pro-inflammatory cytokines.
What are the cellular changes associated with increased dryness and scaliness of older skin?
Cellular heterogeneity leading to epidermal dyscrasia characterized by reduced mitotic activity, lengthened cell cycle, and increased migration time.
How does aging affect collagen in the dermis?
Aging leads to biochemical changes in collagen resulting in increased rigidity and impaired wound healing.
What is solar elastosis and how does it relate to aging skin?
Solar elastosis is characterized by replacement of normal elastic fibers with a disordered mass of elastotic material, reflecting the impact of chronic sun exposure.
What changes occur in the ground substance of the skin with aging?
With aging, the ground substance is affected, leading to decreased interaction of protein and water.
What cellular changes contribute to increased dryness and scaliness of older skin?
Cellular heterogeneity results in epidermal dyscrasia, reduced mitotic activity, and increased migration time.
How does the density of melanocytes change in photodamaged skin with age?
Melanocytes double in density, but functional melanocyte numbers decline by up to 20% per decade.
What is the relationship between melanocyte decline and skin cancer risk in the elderly?
The decrease of melanocytes is associated with a decrease in protective melanin, leading to an elevated risk of skin cancer.
What happens to the incidence of melanocytic nevi with age?
The incidence of melanocytic nevi declines with age.
What age-related changes occur in the dermis regarding collagen?
There is increased rigidity and impaired wound healing due to a reduction of collagen types I and III.
How does aging affect the collagen-synthetic capacity of fibroblasts?
There is an age-dependent difference in the collagen-synthetic capacity of aging fibroblasts, leading to lower collagen synthesis in intrinsically aged skin.
What is the effect of elevated MMP activity in chronically photodamaged skin?
Elevated MMP activity creates a microenvironment of fragmented collagen, impairing fibroblast function and leading to abnormal collagen homeostasis.
What is solar elastosis?
It is characterized by the replacement of normal elastic fibers with a disordered mass of elastotic material localized near the dermal-epidermal junction in photodamaged skin.
How do proteoglycans and glycosaminoglycans change with aging?
They are affected by aging, leading to decreased interaction of protein and water, although GAGs are increased in photoaged skin.
What happens to hyaluronic acid levels in intrinsically aged skin?
There is a progressive decline of hyaluronic acid, possibly secondary to decreased secretion.
What happens to melanocyte density in photodamaged skin?
Melanocyte density doubles in photodamaged skin, but functional melanocytes decline by up to 20% per decade, increasing the risk of skin cancer due to decreased protective melanin.
How does solar elastosis affect the dermis in photodamaged skin?
This condition impairs the skin’s elasticity and resilience.
What role do proteoglycans and glycosaminoglycans play in the aging of skin?
In aging skin, particularly photodamaged skin, proteoglycans and glycosaminoglycans (GAGs) are affected, leading to decreased interaction of proteins and water, and dehydration due to abnormal elastotic material.
How does the decline of hyaluronic acid in intrinsically aged skin affect skin hydration?
The decline of hyaluronic acid reduces the skin’s ability to retain moisture, leading to increased dryness and loss of elasticity.
What age-related change contributes to impaired lipid-processing enzymatic activity in xerosis?
Abnormal stratum corneum acidification between ages 50–80 contributes to impaired lipid-processing enzymatic activity.
What is the histologic alteration called in a patient with photodamaged skin that has a disordered mass of elastotic material near the DEJ?
This histologic alteration is called solar elastosis.
What is the consequence of diminished lamellar bilayers in the stratum corneum interstices in xerosis?
Diminished lamellar bilayers lead to impaired skin barrier function.
What is the source of MMP-1 and other matrix metalloproteinases in photodamaged skin?
MMP-1 and other matrix metalloproteinases are derived from dermal fibroblasts in photodamaged skin.
What cellular change contributes to increased dryness and scaliness in xerosis?
A decrease in epidermal filaggrin contributes to increased dryness and scaliness in older skin.
What is the consequence of impaired lipid-processing enzymatic activity due to abnormal stratum corneum acidification?
Abnormal stratum corneum acidification results in impaired lipid-processing enzymatic activity, contributing to xerosis.
What is the consequence of reduced responsiveness of Langerhans cells in xerosis?
Reduced responsiveness of Langerhans cells contributes to impaired immune surveillance in aged skin.
What changes occur in hair density in elderly men?
Elderly men experience a drop in density of chest, axillary, and pubic hair, while there is an increase in hair in other body sites such as the nostrils and eyebrows.
What hormonal changes might explain coarse hair growth on the chin and upper lip in elderly women?
It is likely due to the unopposed influence of testosterone resulting from falling estrogen levels.
What is senescent alopecia?
Senescent alopecia refers to the age-related thinning of hair, while androgenetic alopecia can occur at an earlier age.
How prevalent is gray scalp hair among the elderly?
Nearly half of the population has at least 50% gray scalp hair by age 60.
What causes hair graying in the elderly?
Progressive depletion of melanocytes in the hair bulb.
How does nail growth change with age?
The rate of linear nail growth increases until approximately 25 years old, then drops off.
What changes occur in the texture of nails in the elderly?
Nails become more brittle and may exhibit ridging due to variations in lipid composition.
What happens to eccrine glands with age?
Both the number and output of eccrine glands decline with age, leading to decreased sweating and increased vulnerability to heat stroke.
What are solar lentigines?
Solar lentigines, also known as senile lentigines or liver spots, are well-defined patches of hyperpigmentation associated with UV exposure, common in fair-skinned individuals.
What are seborrheic keratoses?
Seborrheic keratoses are benign papules or plaques that vary in color and may have a waxy or wart-like appearance.
What is a senile angioma?
Senile angioma, or cherry angioma, are small, circular or oval red papules resulting from the proliferation of blood vessels.
How does the incidence of skin cancer change with age?
The incidence of skin cancer, including both melanoma and non-melanoma skin cancers, increases exponentially over a lifetime.
What is the typical presentation of melanoma in elderly males?
Elderly males present with thicker melanomas and have increased mortality.
What is the relationship between UV exposure and the risk of different types of skin cancer?
Squamous cell cancer and actinic keratosis are associated with habitual sun exposure; basal cell cancer and malignant melanoma are linked to a history of habitual or intense intermittent sun exposure.
What are the clinical characteristics of Merkel cell carcinoma summarized by the acronym AEIOU?
Asymptomatic, Expanding rapidly, Immune compromised, Older than 50, UV exposed site on a person of fair skin.
What are the common presentations and characteristics of Kaposi sarcoma?
Kaposi sarcoma (KS) is associated with HHV-8 and has four variants: Classic KS, AIDS-associated KS, Iatrogenic post-transplantation KS, and endemic African KS. KS lesions are purple, red, or brown macules, plaques, and nodules affecting the face or lower extremities.
What are the potential etiologic factors contributing to xerosis?
Age-associated reduction in activity of sebaceous and sweat glands, alterations in lipid composition, impaired filaggrin production, intrinsic changes in keratinization, and associated chronic conditions.
What is asteatotic eczema and how is it characterized?
Asteatotic eczema, also known as winter itch or eczema craquele, is characterized by dry, extremely pruritic, fissured skin with scales. It is a complication of xerosis.
What is impaired filaggrin production associated with?
Impaired filaggrin production is associated with intrinsic changes in keratinization and chronic conditions like renal failure, liver disorders, lower leg atherosclerosis, autoimmune diseases, and hepatitis C virus.
What underlying conditions can cause pruritus?
Pruritus can be caused by xerosis, underlying systemic diseases or malignancies such as diabetes mellitus, thyroid disorders, renal and liver failure, malignant neoplasms like lymphoma or leukemia, and is a defining characteristic of polycythemia vera.
What are the common bacterial infections associated with Staphylococci?
Staphylococci frequently cause impetigo, cellulitis, and in older individuals, orbital cellulitis due to contiguous spread from paranasal sinuses or metastatic spread from a systemic focus.
How can erysipelas be distinguished from cellulitis?
Erysipelas can be distinguished from cellulitis by its demarcated borders.
What is necrotizing fasciitis and what are its associated risks?
Necrotizing fasciitis is often caused by Streptococcus and is associated with increased morbidity and mortality. Elderly individuals are at risk for carriage of methicillin-resistant Staphylococcus aureus, which is often implicated in cases of necrotizing fasciitis.
What type of skin cancer is associated with habitual sun exposure?
Squamous cell cancer and actinic keratosis are associated with habitual sun exposure.
What type of skin cancer is linked to intense intermittent sun exposure?
Basal cell cancer and malignant melanoma are linked to intense intermittent sun exposure.
What is a characteristic of Merkel cell carcinoma?
Merkel cell carcinoma is characterized by a painless, rapidly growing nodule that may be flesh-colored or bluish-red.
What acronym summarizes the clinical characteristics of Merkel cell carcinoma?
The acronym AEIOU summarizes the clinical characteristics: Asymptomatic, Expanding rapidly, Immune compromised, Older than 50, UV exposed site on a person of fair skin.
What is angiosarcoma?
Angiosarcoma is a cancer of the inner lining of blood vessels, commonly presenting on the head and neck.
What are the variants of Kaposi sarcoma?
The variants of Kaposi sarcoma include Classic KS, AIDS-associated KS, iatrogenic post-transplantation KS, and endemic African KS.
What is xerosis and what factors contribute to it?
Xerosis is dry skin associated with age-related reduction in sebaceous and sweat gland activity, lipid composition alterations, and impaired filaggrin production.
What is asteatotic eczema?
Asteatotic eczema is characterized by dry, extremely pruritic, fissured skin with scales, complicated by dermatitis.
What bacteria commonly causes impetigo and cellulitis?
Staphylococci commonly cause impetigo and cellulitis.
What are the potential etiologic factors contributing to xerosis?
Potential etiologic factors contributing to xerosis include age-associated reduction in activity of sebaceous and sweat glands, alterations in lipid composition, impaired filaggrin production, intrinsic changes in keratinization, and associations with chronic conditions like renal failure, liver disorders, and autoimmune diseases.
What distinguishes erysipelas from cellulitis?
Erysipelas is a B-hemolytic streptococcal infection of the upper dermis that spreads to the lymphatics, distinguished from cellulitis by its demarcated borders.
What is a common risk factor for scabies in the elderly?
Residents of nursing homes and other communal living arrangements are at increased risk for scabies.
What fungal infection affects 80% of patients older than 60 years?
Tinea pedis affects 80% of patients older than 60 years.
What is herpes zoster (shingles) caused by?
Herpes zoster is caused by the reactivation of the varicella zoster virus in adults.
What is postherpetic neuralgia?
Postherpetic neuralgia is pain that persists following an acute attack of herpes zoster.
What skin condition is characterized by indurated skin with brownish red pigmentation?
Lipodermatosclerosis is characterized by indurated skin with brownish red pigmentation.
What contributes to the increased occurrence of decubitus ulcers in the elderly?
Decubitus ulcers are more common in the elderly due to age-related skin atrophy, decline in physical mobility, urinary and fecal incontinence, and malnutrition.
What is senile purpura and what causes it?
Senile purpura is the recurrent formation of ecchymoses on sun-exposed extensor surfaces due to age-related skin thinning and sun-induced damage, leading to increased fragility of microvasculature.
What is bullous pemphigoid and who does it affect?
Bullous pemphigoid is an autoimmune blistering disorder that affects patients older than 60 years, manifesting as urticarial papules and plaques that progress into large tense bullae.
What factors increase the risk of drug eruptions in the elderly?
Increased risk of drug eruptions in the elderly is due to polypharmacy, along with declines in renal, cardiac, and liver function that negatively impact drug metabolism and excretion.
What are the common skin infections associated with aging and their causative agents?
Common skin infections in the elderly include:
- Scabies | Sarcoptes scabiei | Increased risk in communal living, less severe pruritus and inflammation
- Dermatophytes | Tinea species (capitis, corporis, pedis, unguium) | Tinea pedis affects 80% of patients over 60 years old
- Candida | Candida albicans | Frequent source of cutaneous infections
- Pityrosporum | Pityrosporum ovale | Causes seborrheic dermatitis, tinea versicolor, folliculitis
- Herpes zoster | Varicella zoster virus | Painful vesicular rash in dermatomal distribution
- Herpes simplex | Herpes simplex virus | Vesicular eruptions in genital and perioral regions
What is senile purpura and what are its underlying causes?
Senile purpura, also known as Bateman purpura, is characterized by recurrent formation of ecchymoses on sun-exposed extensor surfaces of the arms or hands in elderly patients. The underlying causes include age-related skin thinning and sun-induced damage to connective tissue, leading to increased fragility of microvasculature.
What are the risk factors associated with bullous pemphigoid in elderly patients?
Risk factors for bullous pemphigoid in elderly patients include neurologic disorders (e.g., dementia, Parkinson’s disease), psychiatric disorders, bedridden condition, and chronic polypharmacy.
What is the likely diagnosis for a patient with a painful vesicular rash in a dermatomal distribution?
The likely diagnosis is herpes zoster (shingles), caused by the reactivation of the varicella-zoster virus.
What autoimmune condition might be indicated by tense bullae and significant pruritus in a 60-year-old patient?
This presentation is indicative of bullous pemphigoid, an autoimmune blistering disorder.
What condition might recurrent ecchymoses on sun-exposed areas in a 70-year-old patient indicate?
This condition is indicative of senile purpura, caused by age-related skin thinning and sun-induced connective tissue damage.
What is the likely cause of morbilliform eruptions in a 70-year-old patient with a history of polypharmacy?
The likely cause is a drug eruption, as polypharmacy increases the risk of such reactions in the elderly.
What complication might follow a painful vesicular rash preceded by pain in the affected area?
Postherpetic neuralgia, characterized by persistent pain following an acute attack of herpes zoster, might follow.
Is seborrheic keratosis due to increased UV exposure?
False. Seborrheic keratosis is independent of UV exposure.
What type of UV exposure is associated with squamous cell carcinoma (SCC) and actinic keratosis (AK)?
Habitual sun exposure is associated with SCC and AK.
What is more commonly seen in extrinsic skin aging?
Solar elastosis is more commonly seen in extrinsic skin aging.
Which layer of the skin is associated with squamous cell carcinoma?
The stratum spinosum (spinous cell layer) is associated with squamous cell carcinoma.
Is solar elastosis more commonly seen in intrinsic or extrinsic skin aging?
Extrinsic skin aging.
Skin change associated with prolonged UV exposure?
Solar elastosis.
A 70-year-old patient has a history of UV exposure and presents with seborrheic keratosis. Is this condition related to UV exposure?
Seborrheic keratosis is independent of UV exposure and is likely a result of impaired focal epidermal homeostasis.
