Excess body weight places a great strain on nearly all domains of the body’s functions. As the trend of obesity remains unchecked, dermatologists will continue to see issues associated with obesity ꟷ often the result of superficial physiologic reactions to the presence of excess fatty tissue as well as underlying pathophysiologic changes associated with increased adipose fat.1-3
Obesity has many cutaneous manifestations, including striae, intertrigo, plantar hyperkeratosis, lymphedema, acanthosis nigricans, and a greater risk of skin infections and melanoma.1,3 It also contributes to inflammatory dermatologic conditions such as psoriasis and poor wound healing.1
Skin Changes Associated With Obesity
General skin features of people with obesity (defined as a body mass index [BMI] of 30 or higher) are often altered1,3 due to multiple obesity-related factors. A 2017 study3 of American women found that skin barrier and moisturizing functions were significantly impaired by obesity, resulting in considerable dryness and roughness, compared with nonobese women. Skin coloration changes such as facial redness believed to be due to dilation of the local blood vessels in response to inflammation were noted, as was reduced yellow coloration. Conversely, scaliness and roughness were products of systemic inflammation combined with insulin resistance, demonstrated by altered levels of interleukin (IL)-6, leptin, adipokines, and insulin.
Other localized skin manifestations tied to obesity include the following:
· Skin ulcers, usually on the lower leg, are a common result of venous insufficiency due to obesity. In the presence of diabetes, skin ulcers can be extremely resistant to therapy.1
- Atopic eczema, due to chronic inflammation and increased secretion of IL-6.1
- Lymphedema, an area of subcutaneous soft, pitted swelling, occurs most frequently on the shins as a result of infection and obstruction of local lymphatic circulation.1,2
- Striae caused by excessive stretching of the skin in areas with large amounts of adipose fat tissue, such as the breasts, buttocks, abdomen, hips, and thighs. They appear first as erythematous linear bands, which turn purple and then white over time, becoming atrophic and depressed.1,2
- Skin tags, small flesh-colored asymptomatic lesions, are often found around eyelids, neck, and armpits.1,4
- Acanthosis nigricans, involving areas of hyperpigmented plaques near skin folds, may have a surface texture described as velvety, warty, leathery, or papillomatous. The appearance of plaques increases with the degree of obesity. The condition can be benign or malignant and is considered a marker for underlying systemic endocrine diseases such as diabetes or cancer.4
- Plantar hyperkeratosis of the foot refers to a diffuse thickening of the skin of the heel, arch, and plantar region of the large toe. It is a common consequence of both diabetes and obesity and is the most common dermatological complaint among persons with morbid obesity.4
Conditions Associated With Large Skin Folds
The chronic inflammatory skin condition hidradenitis suppurativa is often aggravated by the number and depth of skin folds, which increase with greater weight gain.2,5 This condition generally occurs in the armpit and groin and in skin folds, areas on the body given to friction (skin-to-skin and skin-to-clothing contact) as the patient moves. Hidradenitis suppurativa often begins with follicular plugging, which triggers inflammation and abscess formation.5 Further development into sinus tracts often promotes secondary infection of the area.
Dermatologic Infections Associated With Obesity
Patients with obesity are at higher risk of skin infections such as folliculitis, candidiasis, furunculosis, erythrasma, and tinea cruris as a result of obesity and comorbid conditions such as diabetes and impaired circulation.1,2 These infections most often occur in and around skin folds of the lower genital region and around the breasts, where increased moisture, body heat, and sweating contribute to the colonization of yeast and other bacteria.1,2
Other, more serious conditions may also develop, including the following:
· Intertrigo is caused by a combination of skin irritation and infection, most often from candidal colonization.2,4
· Cellulitis, an acute, rapidly spreading inflammatory infection of the skin and subcutaneous tissue, often occurs in the lower extremities. It is common in obese patients, triggered frequently by disruption of the cutaneous barrier and/or obstruction of venous or lymphatic flow.4
Obesity is associated with a worsened prognosis of psoriasis and is considered an independent risk factor development of this chronic inflammatory skin disorder through the production of macrophages from adipose fat.1,6,7 Because visceral adipose fat is increased with obesity, the production of proinflammatory cytokines, including tumor necrosis factor-α, IL-6, Il-8, Il-17, Il-18, and monocyte chemoattractant protein-1, and adipokines, such as chemerin, visfatin, leptin, and adiponectin, also increases, stimulating autonomic inflammatory responses.6,7 Reduction of body weight has shown a direct correlation to reduced severity of psoriasis symptoms.1,6,7 Obesity also interferes with the pharmacodynamics of drugs used to treat psoriasis and can increase the risks of adverse events.7
All specialists will continue to see a rise in obesity-related complications, and dermatologists will be called on to treat a wide-ranging conditions related to weight issues. Many of the autonomic characteristics of skin are altered and, in some cases, impaired by obesity. Weight management may soon come under the dermatologists’ purview as a component of intervention for cutaneous manifestations of obesity, in addition to other treatments.1,2
1. Shipman AR, Millington GWM. Obesity and the skin. Br J Dermatol. 2011;165:743-750.
2. Scheinfeld NS. Obesity and dermatology. Clin Dermatol. 2004;22:303-309.
3. Mori S, Shiraishi A, Epplen K, et al. Characterization of skin function associated with obesity and specific correlation to local/systemic parameters in American women. Lipids Health Dis. 201713;16(1):214. doi: 10.1186/s12944-017-0608-1
4. Hahler B. An overview of dermatological conditions commonly associated with the obese patient. Ostomy Wound Manage. 2006;52:34-36, 38, 40 passim.
6. Chiricozzi A, Raimondo A, Lembo S, et al. Crosstalk between skin inflammation and adipose tissue-derived products: pathogenic evidence linking psoriasis to increased adiposity [abstract]. Expert Rev Clin Immunol. 2016;12:1299-1308.
7. Owczarczyk-Saczonek A, Placek W. Compounds of psoriasis with obesity and overweight [abstract]. Postepy Hig Med Dosw (Online). 2017;71:761-772.