Obesity and dermatology

Obesity is associated with a number of dermatoses. It affects cutaneous sensation, temperature regulation, foot shape, and vasculature. Acanthosis nigricans is the most common dermatological manifestation of obesity. Skin tags are more commonly associated with diabetes than with obesity. Obesity increases the incidence of cutaneous infections that include: candidiasis, intertigo, candida folliculitis, furunculosis, erythrasma, tinea cruris, and folliculitis. Less common infections include cellulitis, necrotizing fasciitis, and gas gangrene. Leg ulcerations, lymphedema, plantar hyperkeratosis, and striae are more common with obesity. Hormonal abnormalities and genetic syndromes (Prader-Willi) are related to obesity and its dermatoses; however, cellulite is not related to obesity.     

Obesity and the skin: skin physiology and skin manifestations of obesity

Obesity is widely recognized as an epidemic in the Western world; however, the impact of obesity on the skin has received minimal attention. The purpose of this article is to highlight the association between obesity and dermatologic conditions. We review the impact of obesity on the skin, including skin physiology, skin manifestations of obesity, and dermatologic diseases aggravated by obesity. Obesity is responsible for changes in skin barrier function, sebaceous glands and sebum production, sweat glands, lymphatics, collagen structure and function, wound healing, microcirculation and macrocirculation, and subcutaneous fat. Moreover, obesity is implicated in a wide spectrum of dermatologic diseases, including acanthosis nigricans, acrochordons, keratosis pilaris, hyperandrogenism and hirsutism, striae distensae, adiposis dolorosa, and fat redistribution, lymphedema, chronic venous insufficiency, plantar hyperkeratosis, cellulitis, skin infections, hidradenitis suppurativa, psoriasis, insulin resistance syndrome, and tophaceous gout. We review the clinical features, evidence for association with obesity, and management of these various dermatoses and highlight the profound impact of obesity in clinical dermatology. LEARNING OBJECTIVE: After completing this learning activity, participants should be aware of obesity-associated changes in skin physiology, skin manifestations of obesity, and dermatologic diseases aggravated by obesity, and be able to formulate a pathophysiology-based treatment strategy for obesity-associated dermatoses.     

Dermatoses in overweight and obese children and their relationship with insulin and skin color

Background/Aim

The aim of the present study was to investigate the prevalence of obesity-related dermatoses in obese children, and the association between these dermatoses and insulin resistance as well as skin color.

Methods

Obese, overweight, and normal weight children according to body mass index who were followed up and treated in the outpatient clinics were included in the study. Dermatological examinations of the participants were performed, and fasting insulin and glucose levels were checked.

Results

The obese and overweight children were evaluated as the patient group (70 girls, 41 boys, mean age: 12.37 ± 3.14 years). One hundred one healthy children with normal weight were determined as the control group (59 girls, 42 boys, mean age: 12.15 ± 2.43). The first five common dermatoses in the patient group when compared with the control group were keratosis pilaris (KP), striae distensae, hyperhidrosis, acanthosis nigricans (AN), and plantar hyperkeratosis. The first five dermatoses which were positively correlated with formation and insulin resistance were KP, striae distensae, AN, hyperhidrosis, and plantar hyperkeratosis. According to the Fitzpatrick skin scale, we found that the darker the skin color, the higher the probability of AN and KP (OR, 0.298; 95% CI, 0.106–0.834, p = 0.021; OR, 0.306; 95% CI, 0.117–0.796, p = 0.015, respectively).

Conclusion

Some dermatoses associated with obesity and insulin resistance were not found in obese children, or there was no significant association. These results indicate that many skin morbidities may be prevented by preventing and treating obesity and insulin resistance in the early period.     

Acanthosis nigricans in obese patients: Presentations and implications for prevention of atherosclerotic vascular disease

Acanthosis nigricans is traditionally characterized by hyperpigmented, velvety plaques of body folds. Involvement of other areas occurs as well. The condition is caused by hyperinsulinemia, a consequence of insulin resistance that occurs associated with obesity. As the frequency and degree of obesity increase in the population, a concomitant increase in acanthosis nigricans can be expected. The dermatologist has an important role in identifying the subset of obese patients with acanthosis nigricans. These patients have hyperinsulinemia and may be at greater risk of consequent atherosclerotic cardiovascular disease. It is essential for dermatologists to recognize the many presentations of acanthosis nigricans to identify patients at risk for associated medical conditions. This article illustrates a variety of presentations of acanthosis nigricans associated with insulin resistance.     

Acanthosis Nigricans Associated with Insulin Resistance

The association of acanthosis nigricans, skin tags, diabetes mellitus due to insulin resistance, and obesity in adolescents and young adults represents a well defined syndrome. Hyperandrogenism may also be present. The endocrine origin of this condition is beyond doubt. Insulin and insulin-like growth factor-1, and their receptors on keratinocytes are obviously involved in the complex regulations leading to the peculiar epidermal hyperplasia. This condition is unrelated to other types of acanthosis nigricans, including the congenital and the paraneoplastic types. Control of obesity contributes largely to reverse the whole process, essentially by reducing both insulin resistance and compensatory hyperinsulinemia. Several drugs including metformin, octreotide, retinoids and topical colecalciferol (vitamin D(3)) analogs are also beneficial in clearing acanthosis nigricans.     

Acanthosis nigricans and insulin resistance associated with hypothyroidism

An obese 15-year-old boy with a one-year history of acanthosis nigricans was found to have primary hypothyroidism, with a thyrotropin level in excess of 50 microU/mL. At the same time, he was found to have subclinical insulin resistance. Therapy with thyroxine resulted in weight loss, reversal of hyperinsulinemia, and resolution of the acanthosis nigricans. Hypothyroidism can be added to the list of endocrine diseases associated with acanthosis nigricans. This is unlikely to be a direct effect of the hypothyroid state, but may instead be an indirect action mediated through obesity and subsequent insulin resistance. Insulin resistance and hyperinsulinemia seem to be commonly associated with (and perhaps causative of) the acanthosis nigricans that is seen in many endocrine diseases.     

Screening of glucose/insulin metabolic alterations in men with multiple skin tags on the neck

Multiple skin tags appear associated with abnormalities in glucose/insulin metabolism. Clinical and metabolic glucose/insulin characteristics of men with multiple (8 or more) skin tags on the neck were compared with a control group with few or none. Both groups were divided in two subgroups according to normal or abnormal laboratory findings. In the study subgroup with normal laboratory findings the number of skin tags varied from 8–33, whereas in those with abnormal laboratory findings the range was 9–65. Eight or more skin tags were related with statistically significant laboratory glucose/insulin abnormalities: basal hyperinsulinemia (p<0.002), postprandial hyperinsulinemia (p<0.003), and postprandial hyperglycemia (p<0.01). In the multiple skin tag group 77 % had diverse laboratory abnormalities, including insulin resistance, basal hyperinsulinemia, postprandial hyperinsulinemia, glucose intolerance or type 2 diabetes, in contrast with the control group, where only 33 % showed laboratory abnormalities. One‐third of the study group had acanthosis nigricans. Only 15 % of patients with metabolic abnormalities did not show any cutaneous expression of glucose/insulin alterations (9 or more skin tags on the neck, acanthosis nigricans, or waist circumference greater than 95 cm). Multiple skin tags were more sensitive than acanthosis nigricans in identifying those with alterations in the glucose/insulin metabolism (77 vs. 32 % respectively), although less specific (68 vs.100%). Multiple skin tags should raise suspicion of insulin resistance or hyperinsulinemia.     

Skin manifestations of obesity: a comparative study

Background Obesity is one of the world’s biggest health problems nowadays. Little research has been done on the skin diseases that affect obese patients. Objective To study the prevalence of skin manifestations in obese patients compared with a control group of normal‐weight patients. Methods A total of 76 obese patients [body mass index (BMI) ≥30 kg/m²] and 73 with normal‐weight volunteers (BMI 18.5–24.9 kg/m²) were included in the study and had their complete medical history and skin examination evaluated by the same examiner. All patients were investigated for the presence of metabolic syndrome. Results The dermatoses that showed a statistically significant relationship with obesity, compared with the control group were: striae (P < 0.001), plantar hyperkeratosis (P < 0.001), acrochordons (P = 0.007), intertrigo (P < 0.001), pseudoacanthosis nigricans (P < 0.001), keratosis pilaris (P = 0.006), lymphedema (P = 0.002) and bacterial infections (P = 0.05). The presence of striae, pseudoacanthosis nigricans and bacterial infections were also found to be correlated with the degree of obesity. Conclusions Obesity is strongly related to several skin alterations that could be considered as markers of excessive weight. Skin care of obese patients deserves particular attention, not only because of the high prevalence of cutaneous alteration but mainly because many of these disorders are preventable and could be treated, improving patient’s quality of life.     

The effect of obesity on skin disease and epidermal permeability barrier status in children

Abstract: Obese adult patients have many dermatoses, such as skin tags, candida infection, cellulite, and intertrigo, but only limited data have been published on obese children and the barrier function of their skin. Sixty‐five overweight and obese children (n = 40, BMI 85th–95th percentile; n = 25, BMI > 95th percentile) (aged 8–15; mean age 11.6) and 30 normal‐weight controls (aged 7–15; mean age 11.1) underwent a clinical evaluation and calculation of transepidermal water loss (TEWL). Higher weight percentile was associated with a higher incidence of some dermatoses. Skin tags were found in 40% of subjects in the 95th percentile and 2.5% of those in the 85th percentile. Striae distensae were observed in 32% of patients in the 95th percentile and 22.5% of those in the 85th percentile. Plantar hyperkeratosis was observed only in 20% of the 95th percentile subjects and was not observed in the other groups. TEWL values at the forearm site were significantly higher (p < 0.05) in obese children than in the control group, but no significant differences in TEWL values according to BMI level were found between the two groups of obese children. Degree of obesity influences the incidence of some associated dermatoses; skin tags, striae distensae, and plantar hyperkeratosis were more frequent in children in the 95th percentile of BMI. Obesity increases the TEWL rate, suggesting that obese children might become more easily overheated as weight increases, with more profuse sweating because of the thick layers of subcutaneous fat.     

The impact of obesity on skin disease and epidermal permeability barrier status

Background Obese subjects frequently show skin diseases. However, less attention has been paid to the impact of obesity on skin disorders until now. Objective The purposes of this study are: to highlight the incidence of some dermatoses in obese subjects and to study the water barrier function of the obese skin using transepidermal water loss (TEWL). Methods Sixty obese subjects and 20 normal weight volunteers were recruited. Obese group was further divided into three body mass index (BMI) classes: class I (BMI 30–34.9 kg/m²), class II (BMI 35–39.9 kg/m²) and class III (BMI 40 g/m²). All subjects attended dermatological examination for skin diseases. To assess barrier function, TEWL measurements were performed on the volar surface of the forearm using a tewameter. Results The results of this study showed that: (i) obese subjects show a higher incidence of some dermatoses compared with normal‐weight controls; in addition the dermatoses are more, frequent as BMI increases; (ii) the rate of TEWL is lower in obese subjects, than in the normal‐weight subjects, particularly in patients with intra‐abdominal obesity. Conclusion Specific dermatoses as skin tags, striae distensae and plantar hyperkeratosis, could be considered as a cutaneous stigma of severe obesity. The low permeability of the skin to evaporative water loss is observed in obese subjects compared with normal weight control. Although the physiological mechanisms are still unknown, this finding has not been previously described and we believe that this may constitute a new field in the research on obesity.     

Dermatology of androgen-related disorders

Hyperandrogenism in women can be caused by various conditions, the most prevalent of which is polycystic ovary syndrome. Common dermatologic manifestations of hyperandrogenism include hirsutism, acne, acanthosis nigricans, and androgenic alopecia. Hirsute women often have increased activity of 5 alpha-reductase, the enzyme that converts the androgen testosterone to its active metabolite, in hair follicles. Likewise, androgens affect the formation of acne by increasing sebum production from sebaceous glands in the skin. The diagnosis of polycystic ovary syndrome includes a complete history, physical examination with emphasis on evidence of androgen excess, and appropriate laboratory investigation to exclude other causes of hyperandrogenism. Treatments for the dermatologic conditions of hyperandrogenism include lifestyle modification, oral contraceptives, antiandrogens, and insulin-sensitizing medications.     

假性黑棘皮病肥胖儿童：2型糖尿病的高危人群

目的探讨肥胖儿童伴假性黑棘皮病与胰岛素抵抗及2型糖尿病的关系。方法对42例肥胖伴假性黑棘皮病儿童,60例单纯性肥胖儿童及20例正常儿童的空腹血糖及胰岛素水平、空腹血糖/ 胰岛素比值及人体测量学参数[腰围/臀围比值(wHR)、全身体脂含量、体脂百分数、体质指数]进行分析比较,并对肥胖伴假性黑棘皮病儿童组与单纯性肥胖儿童组行葡萄糖耐量试验,以比较两组患儿的糖耐量异常情况。结果假性黑棘皮病组有2例诊断为2型糖尿病,21例糖耐量异常,明显高于单纯肥胖儿童组;葡萄糖耐量试验提示60 min及120 min的血糖水平显著高于单纯肥胖组(P<0.01)。人体测量学参数包括腰围/臀围比值、全身体脂含量、体脂百分数、体质指数及空腹血胰岛素水平明显高于单纯性肥胖组(P<0.01)和对照组(P<0.01),空腹血糖/胰岛素比值明显低于单纯肥胖组(P<0.0I)和对照组(P<0.01)。结论儿童假性黑棘皮病与肥胖、高胰岛素血症、胰岛素抵抗密切相关,是发生2型糖尿病的高危人群。     

Oral acanthosis nigricans, tripe palms and sign of leser-trélat in a patient with gastric adenocarcinoma

Acanthosis nigricans (AN), tripe palms (TP) and the sign of Leser-Trélat (LT) may be seen with the presence of malignancy. Acanthosis nigricans may have a mucocutaneous localization involving the oral mucosa with papillomatous and verrucous lesions usually on the lips and buccal mucosa. These paraneoplastic dermatoses are generally linked with intra-abdominal malignancy, most often gastric adenocarcinoma. Improvement of the associated dermatoses after the treatment of the malignancy has been frequently observed. We report the case of a 53-year-old man suffering from advanced gastric adenocarcinoma, in which metastases seemed to sustain all three paraneoplastic dermatoses. To the best of our knowledge this is the first case of a patient showing manifestations of all three paraneoplastic dermatoses. Patients presenting with this set of dermatoses should be suspected to harbor an occult malignancy, or have persistence of a known malignancy.     

Cutaneous manifestations of endocrine disorders: a guide for dermatologists

Dermatologists may commonly see skin lesions that reflect an underlying endocrine disorder. Identifying the endocrinopathy is very important, so that patients can receive corrective rather than symptomatic treatment. Skin diseases with underlying endocrine pathology include: thyrotoxicosis; hypothyroidism; Cushing syndrome; Addison disease; acromegaly; hyperandrogenism; hypopituitarism; primary hyperparathyroidism; hypoparathyroidism; pseudohypoparathyroidism and manifestations of diabetes mellitus. Thyrotoxicosis may lead to multiple cutaneous manifestations, including hair loss, pretibial myxedema, onycholysis and acropachy. In patients with hypothyroidism, there is hair loss, the skin is cold and pale, with myxedematous changes, mainly in the hands and in the periorbital region. The striking features of Cushing syndrome are centripetal obesity, moon facies, buffalo hump, supraclavicular fat pads, and abdominal striae. In Addison disease, the skin is hyperpigmented, mostly on the face, neck and back of the hands. Virtually all patients with acromegaly have acral and soft tissue overgrowth, with characteristic findings, like macrognathia and enlarged hands and feet. The skin is thickened, and facial features are coarser. Conditions leading to hyperandrogenism in females present as acne, hirsutism and signs of virilization (temporal balding, clitoromegaly).A prominent feature of hypopituitarism is a pallor of the skin with a yellowish tinge. The skin is also thinner, resulting in fine wrinkling around the eyes and mouth, making the patient look older. Primary hyperparathyroidism is rarely associated with pruritus and chronic urticaria. In hypoparathyroidism, the skin is dry, scaly and puffy. Nails become brittle and hair is coarse and sparse. Pseudohypoparathyroidism may have a special somatic phenotype known as Albright osteodystrophy. This consists of short stature, short neck, brachydactyly and subcutaneous calcifications. Some of the cutaneous manifestations of diabetes mellitus include necrobiosis lipoidica diabeticorum, diabetic dermopathy, scleredema adultorum and acanthosis nigricans.     

Acanthosis nigricans, insulin resistance and cutaneous virilism

Thirteen patients with the syndrome of acanthosis nigricans and insulin resistance are described. They all had a combination of dermatoses related to hyperandrogenism (cutaneous virilism): hirsuties (II), acne vulgaris (6), hidradenitis suppurativa (5) and androgenic alopecia (4). In addition, 9 out of 13 had keratosis pilaris. The patients had raised fasting plasma insulin levels compared with matched normal controls (P less than 0.01) and increased insulin resistance (P less than 0.02). Insulin resistance correlated with total serum testosterone (rs = 0.65; P less than 0.02).     

Prevalence and significance of acanthosis nigricans in an adult obese population.

BACKGROUND AND DESIGN--Acanthosis nigricans develops commonly in obese individuals, yet its prevalence and significance in an unselected adult obese population has not been determined. To address these issues, 34 patients enrolled in the Adult Obesity Clinic at Parkland Memorial Hospital (Dallas, Tex) were chosen at random and examined. RESULTS--Acanthosis nigricans was observed in fully 74% of patients; its prevalence correlated positively with severity of obesity. Black obese patients demonstrated a greater propensity for manifesting the cutaneous disorder than did white obese individuals. Patients with acanthosis nigricans exhibited fasting plasma insulin levels that were markedly higher than those of nonacanthotic cohorts. CONCLUSIONS--Obesity is a significant risk factor for the development of acanthosis nigricans. Conversely, acanthosis nigricans is a reliable cutaneous marker of hyperinsulinemia in obese individuals.     

Dermatosis en pacientes con sobrepeso y obesidad y su relación con la insulina

IntroductionThe prevalence of obesity has increased worldwide in recent years. Some authors have described skin conditions associated with obesity, but there is little evidence on the association between insulin levels and such disorders.ObjectiveTo describe the skin disorders present in overweight and obese patients and analyze their association with insulin levels.Material and methodsThe study included nondiabetic male and female patients over 6 years of age who were seen at our hospital between January and April 2011. All the patients were evaluated by a dermatologist, who performed a physical examination, including anthropometry, and reviewed their medical history and medication record; fasting blood glucose and insulin were also measured. The patients were grouped according to degree of overweight or obesity and the data were compared using analysis of variance or the χ² test depending on the type of variable. The independence of the associations was assessed using regression analysis.ResultsIn total, 109 patients (95 adults and 13 children, 83.5% female) were studied. The mean (SD) age was 38 (14) years and the mean body mass index was 39.6 ± 8 kg/m². The skin conditions observed were acanthosis nigricans (AN) (in 97% of patients), skin tags (77%), keratosis pilaris (42%), and plantar hyperkeratosis (38%). Statistically significant associations were found between degree of obesity and AN (P = .003), skin tags (P = .001), and plantar hyperkeratosis. Number of skin tags, AN neck severity score, and AN distribution were significantly and independently associated with insulin levels.ConclusionsAN and skin tags should be considered clinical markers of hyperinsulinemia in nondiabetic, obese patients.     

高雄激素血症-胰岛素抵抗-黑棘皮病综合征1例

报告1例高雄激素血症-胰岛素抵抗-黑棘皮病综合征,患者女,14岁。8岁开始肥胖,12岁初潮,1年后停经,唇上部,驱干,四肢毳毛增多,颈部,腋窝,腹股沟等处皮肤色素沉着,呈天鹅绒样增厚。皮损有典型的组织病理改变,血清胰岛素,睾酮水平升高。给予二年双胍治疗3个月后,病情好转。     

The syndrome of acanthosis nigricans, hyperandrogenism and insulin resistance

Two patients with hyperandrogenism secondary to polycystic ovary disease, insulin resistance and acanthosis nigricans are reported. These are the features of a specific syndrome of insulin resistance. One of these patients showed regression of her acanthosis nigricans following treatment with cyclical antiandrogens and oestrogens. Unilateral breast hypoplasia was also noted in this patient, a feature not previously reported in this syndrome. The relationship between hyperandrogenism, insulin resistance and acanthosis nigricans is discussed.     

Quantitative skin color measurements in acanthosis nigricans patients: colorimetry and diffuse reflectance spectroscopy

Tristimulus colorimetry and diffuse reflectance spectroscopy (DRS) are white‐light skin reflectance techniques used to measure the intensity of skin pigmentation. The tristimulus colorimeter is an instrument that measures a perceived color and the DRS instrument measures biological chromophores of the skin, including oxy‐ and deoxyhemoglobin, melanin and scattering. Data gathered from these tools can be used to understand morphological changes induced in skin chromophores due to conditions of the skin or their treatments. The purpose of this study was to evaluate the use of these two instruments in color measurements of acanthosis nigricans (AN) lesions. Eight patients with hyperinsulinemia and clinically diagnosable AN were seen monthly. Skin pigmentation was measured at three sites: the inner forearm, the medial aspect of the posterior neck, and anterior neck unaffected by AN. Of the three, measured tristimulus L*a*b* color parameters, the luminosity parameter L* was found to most reliably distinguish lesion from normally pigmented skin. The DRS instrument was able to characterize a lesion on the basis of the calculated melanin concentration, though melanin is a weak indicator of skin change and not a reliable measure to be used independently. Calculated oxyhemoglobin and deoxyhemoglobin concentrations were not found to be reliable indicators of AN. Tristimulus colorimetry may provide reliable methods for respectively quantifying and characterizing the objective color change in AN, while DRS may be useful in characterizing changes in skin melanin content associated with this skin condition.