Sensitive skin in France: a study on prevalence, relationship with age and skin type and impact on quality of life

Does sensitive skin lie in epidermal barrier impairment or abnormalities? Results from an observational study assessing biophysical parameters

BACKGROUND

The pathophysiology of sensitive skin is largely unknown and no univocal data on the role of the epidermal barrier impairment have been identified. The aim of this study was to assess whether subjects with or without sensitive skin differ for some biophysical skin parameters, which reflect skin barrier integrity or skin hyperactivity.

METHODS

This observational, cross-sectional study included adult volunteers not affected with chronic inflammatory skin diseases who attended the Unit of Dermatology and the Center of Cosmetology of the University of Ferrara, Ferrara, Italy, between March 2021 and November 2022. All subjects, subdivided into those with or without sensitive skin, based on either Lactic Acid Stinging Test (LAST) result or a questionnaire-based skin sensitivity score ≥4, were tested for transepidermal water loss (TEWL), skin elasticity and hydrations and dermographism.

RESULTS

One hundred and eighty-seven subjects were included. No significant differences in terms of TEWL, elasticity and hydration levels were recorded between subjects with sensitive skin and those without, subdivided according to both the LAST result and the questionnaire score. Dermographism was elicited more in subjects with sensitive skin than in the others, although without statistical significance.

CONCLUSIONS

The study failed to find significant biophysical differences between sensitive and non-sensitive skin. Therefore, the role of skin barrier impairment does not appear to be a necessary condition in determining an abnormal skin sensitivity to potentially unpleasant and irritating stimuli. These findings indirectly support the relevance of a peripheral sensory neural hyperactivity in the pathophysiology of sensitive skin.

MiRNA-224-5p regulates the defective permeability barrier in sensitive skin by targeting claudin-5

BACKGROUND

Sensitive skin is hypersensitive to various external stimuli and a defective epidermal permeability barrier is an important clinical feature of sensitive skin. Claudin-5 (CLDN5) expression levels decrease in sensitive skin. This study aimed to explore the impact of CLDN5 deficiency on the permeability barrier in sensitive skin and the regulatory role of miRNAs in CLDN5 expression.

MATERIALS AND METHODS

A total of 26 patients were retrospectively enrolled, and the CLDN5 expression and permeability barrier dysfunction in vitro were assessed. Then miRNA-224-5p expression was also assessed in sensitive skin.

RESULTS

Immunofluorescence and electron microscopy revealed reduced CLDN5 expression, increased miR-224-5p expression, and disrupted intercellular junctions in sensitive skin. CLDN5 knockdown was associated with lower transepithelial electrical resistance (TEER) and Lucifer yellow penetration in keratinocytes and organotypic skin models. The RNA-seq and qRT-PCR results indicated elevated miR-224-5p expression in sensitive skin; MiR-224-5p directly interacted with the 3`UTR of CLDN5, resulting in CLDN5 deficiency in the luciferase reporter assay. Finally, miR-224-5p reduced TEER in keratinocyte cultures.

CONCLUSION

These results suggest that the miR-224-5p-induced reduction in CLDN5 expression leads to impaired permeability barrier function, and that miR-224-5p could be a potential therapeutic target for sensitive skin.

A review of factors influencing sensitive skin: an emphasis on built environment characteristics

Background

Sensitive skin (SS) is a condition characterized by hyperreactivity. Impacting around 37 percent of the worldwide population and exerting an influence on the quality of life for affected individuals. Its prevalence rate has increased due to factors such as elevating stress levels and deteriorating environmental conditions. The exposome factors influencing SS have extended from demographic, biological attributes, and lifestyle to external environments. Built environments (BEs) have demonstrated as root drivers for changes in behaviors and environmental exposure which have the potential to trigger SS, but the review of the associations between BEs and SS is currently lacking.

Objective

This review aims to achieve two primary objectives: (1) Examine exposome factors that exert influence on SS at the individual and environmental levels. (2) Develop a theoretical framework that establishes a connection between BEs and SS, thereby offering valuable insights into the impact of the built environment on this condition.

Methods

An extensive literature search was carried out across multiple fields, including sociology, epidemiology, basic medicine, clinical medicine, and environmental research, with a focus on SS. To identify pertinent references, renowned databases such as PubMed, Web of Science, and CNKI were utilized.

Results

SS is the outcome of interactions between individual attributes and environmental factors. These influencing factors can be categorized into five distinct classes: (1) demographic and socioeconomic characteristics including age, gender, and race; (2) physiological and biological attributes such as emotional changes, skin types, sleep disorders, and menstrual cycles in women; (3) behavioral factors, such as spicy diet, cosmetic use, alcohol consumption, and physical exercise; (4) natural environmental features, including climate conditions and air pollution; (5) built environmental features such as population density, green space availability, road network density, and access to public transportation, also have the potential to affect the condition.

Conclusion

The importance of interdisciplinary integration lies in its ability to ascertain whether and how BEs are impacting SS. By elucidating the role of BEs in conjunction with other factors in the onset of SS, we can provide guidance for future research endeavors and the formulation of interventions aimed at mitigating the prevalence of SS.

Rosacea and seborrheic dermatitis differentially respond to lactic acid sting and capsaicin tests in Chinese women

BACKGROUND

Although rosacea and seborrheic dermatitis share some symptoms of sensitive skin, whether they respond differently to lactic acid sting and capsaicin tests, common tests for diagnosis of sensitive skin, is unknown.

OBJECTIVES

To reveal the cutaneous responses to lactic acid sting (LAST) and capsaicin test (CAT) in females with either rosacea vs. seborrheic dermatitis.

METHODS

A total of 60 patients with rosacea, 20 patients with seborrheic dermatitis and 40 normal controls were enrolled in the study. Their skin sensitivity to stimuli were evaluated following topical application of either 10% lactic acid solution or 0.001% capsaicin solution. Transepidermal water loss (TEWL) rates and erythema indexes were also measured on the face.

RESULTS

In comparison to normal controls, the positive rate to either LAST or CAT was significantly higher in subjects with rosacea (p < 0.001), but not in that with seborrheic dermatitis. Similarly, individuals with rosacea displayed a higher positive rate to both LAST and CAT than those with seborrheic dermatitis and normal controls (p < 0.001). In parallel, the LAST scores and CAT scores in individuals with rosacea were significantly higher than in that with either seborrheic dermatitis or normal controls (p < 0.001). The baseline TEWL rates and erythema indexes were higher in individual with rosacea than in normal controls (p < 0.001). But the baseline TEWL rates and erythema indexes did not differ significantly between subjects with rosacea and that with seborrheic dermatitis. Moreover, LAST scores and CAT scores correlated positively with TEWL (p < 0.0001). TEWL rates were higher in CAT positive than in CAT negative subjects (p < 0.0001). Finally, erythema index correlated positively with CAT scores (p < 0.0001), but not with LAST scores (p = 0.0842).

CONCLUSIONS

Skin responses to LAST and CAT differ between individuals with rosacea and those with seborrheic dermatitis, possibly due to the differences in epidermal permeability barrier and the neurovascular hyperreactivity. The higher LAST and CAT scores, as well as positive rates of both LAST and CAT can be attributable to inferior permeability barrier and the neurovascular hyperreactivity in subjects with rosacea.

Results from an extended study on the reliability of a questionnaire for the diagnosis of sensitive skin: Confirmations and improvements

OBJECTIVE

A recently proposed self-assessment questionnaire aimed at diagnosing sensitive skin provided promising results in a relatively small population. The main objectives were: (i) to assess the reliability of the aforementioned questionnaire in a larger population and verify the cut-off score previously found to predict skin sensitivity (defined as positivity to LAST, lactic acid stinging test) and (ii) to define a formula that yields the probability of a positive LAST result.

METHODS

Adult volunteers were included in this observational, cross-sectional, extended study. Both LAST-positive subjects, who were considered as having sensitive skin ('patients') and negative ones ('controls') completed the questionnaire, which concerned sensitivity to possible triggers of unpleasant skin sensations in real life. A cumulative score (questionnaire-based skin sensitivity score, 0-10) was calculated from the sum of all items.

RESULTS

Three hundred and sixty-four subjects were enrolled, 214 patients and 150 controls. The mean questionnaire-based skin sensitivity score was significantly higher among patients than controls. Using two different methods, cut-off values of 4 and 5 were defined for the identification of LAST-positive subjects, with 76.6% and 72.8% accuracy, respectively. Scores below 4 or above 5 showed a high (80% or better) negative or positive predictive value, respectively. The coefficients found that in multivariate analysis for each questionnaire item, gender and age allowed us to calculate the probability of LAST positivity with higher precision taking into account the 'relative weight' of each factor.

CONCLUSION

With small variations in the results, the self-assessment questionnaire confirmed its reliability for diagnosing sensitive skin in clinical practice.

Clinical studies in Chinese subjects investigating the tolerance and soothing efficacy of a cream and balm containing 4-t-butylcyclohexanol on the sensitivity of facial skin

INTRODUCTION

Asian subjects are particularly prone to skin sensitivity. We developed a facial cream and balm containing 4-t-butylcyclohexanol to provide skin comfort and a soothing effect for sensitive skin.

OBJECTIVES

Assess the dermatological and ophthalmological tolerance and efficacy in improving skin sensitivity of face cream and balm under normal conditions of use by a population known to be particularly prone to this problem.

METHODS

In a monocentric non-randomized open trial, the cream or balm was applied twice daily to the face, neck, and eye contour of 33 stinger subjects with hypersensitive skin (22-63 years old). Assessments included dermatological and ophthalmological physical and functional signs on Day 1 (D1), D8, and D22, and cosmetic acceptability, cutaneous sensitivity according to a stinging test and the sensitive scale, and the soothing efficacy according to a questionnaire on D22.

RESULTS

The cream and balm were very well tolerated. Immediately after application, subjects reported a reduction in the skin's hypersensitivity (93.9% of subjects for the cream and 81.8% for the balm), skin redness (90.9% of subjects for the cream and 87.9% for the balm), sensations of tightness (93.9% for the cream and 97.0% for the balm), and discomfort sensations (93.9% for the cream and 87.9% for the balm). After 21 days, the application of the cream and balm decreased the stinging scores by 65% and 41%, respectively, with 94% and 77% of subjects showing an improvement, respectively. The sensitivity scale questionnaire indicated that the cream and balm significantly and profoundly decreased all negative signs, for example, irritability, stinging, general discomfort, redness, and dryness on D22 compared to D1. On D22, all 15 parameters recorded were improved by 89%-100% by the cream and by 74%-100% by the balm. The majority (90.9% and 96.8% of subjects using the cream and balm, respectively) of the subjects noticed positive changes in their skin condition after using the product for 21 days.

CONCLUSIONS

The cream and balm were very well-tolerated. This study demonstrated that both products controlled and markedly reduced skin hypersensitivity in Asian subjects, with an immediate and lasting skin soothing and repairing effect over 21 days.

Psychological Aspects of Sensitive Skin: A Vicious Cycle

Sensitive Skin Syndrome (SSS) has been the subject of intense research in the past several years. Recent reviews confirm that about 40% of the population report moderate or very sensitive skin, and an additional 30% report slightly sensitive skin. Although certain phenotypes are more susceptible, anyone can suffer from SSS and this condition can manifest in all anatomic sites. A wide variety of environmental and lifestyle factors can trigger SSS symptoms of itching, stinging, burning, pain, and tingling. In order to avoid such triggers, the SSS individuals often alter their behaviors and habits such as restricting their daily activities, and modifying the use of everyday products that non-sensitive individuals take for granted. In addition, there is an association between SSS and some common psychological problems. Sensitive skin symptoms such as itching, stinging, burning and pain can result in sleep disorders, fatigue, stress and anxiety. Conversely, lack of sleep and stress from external sources can make the SSS sufferer more prone to the symptoms. This becomes a vicious cycle that impacts consumers’ quality of life and well-being. We are beginning to understand the importance of the underlying causes that can impact skin conditions. However, in order to better understand the SSS individual, we need to also be aware of the psychological factors that can trigger and/or worsen this skin condition, as well as the psychological stresses the condition places on the individual.

Beneficial Effect of Heat-Killed Lactiplantibacillus plantarum L-137 on Skin Functions in Healthy Participants: A Randomized, Placebo-Controlled, Double-Blind Study

To determine whether consuming heat-killed Lactiplantibacillus plantarum L-137 (HK L-137) influences skin functions, we performed a randomized, placebo-controlled, double-blind study in healthy participants who were conscious of dry skin. A total of 80 healthy participants (20 men, 60 women; mean age, 47.3 years) were assigned to receive a tablet containing HK L-137 or a placebo tablet daily for 12 weeks. Every 4 weeks, the skin water content and transepidermal water loss (TEWL) were measured at the forearm and face, and participants completed two skin-related questionnaires, the Dermatology Life Quality Index and a self-evaluation. The HK L-137 group tended to show greater increases from baseline of water content at the forearm and larger decreases of TEWL at the face. The total scores of both questionnaires improved significantly more in the HK L-137 group. Water content and TEWL improved significantly in participants in the HK L-137 group who were above the median age of study participants or had relatively dry skin. These findings suggest that daily HK L-137 intake can improve dry skin, thereby contributing to skin satisfaction.

Sensitive Skin Syndrome: A Low-Noise Small-Fiber Neuropathy Related to Environmental Factors?

Background and Objectives

Patients frequently complain of mild, transient, unpleasant skin sensations that cannot be diagnosed as common neuropathies. Dermatologists have termed these symptoms “sensitive skin syndrome.” This narrative review was performed for a better knowledge by other specialists.

Databases and Data Treatment

Publications on pain in sensitive skin syndrome were obtained from PubMed.

Results

There is a growing body of data supporting the concept that sensitive skin is a type of small-fiber neuropathy. The arguments are based on clinical data, a decrease in intra-epidermal nerve fiber density, quantitative sensory testing abnormalities and an association with irritable bowel syndrome and sensitive eyes. Sensitive skin is triggered by environmental factors. Sensitive skin is a frequent condition, with a lifetime prevalence of ~50% according to self-reports.

Conclusions

Mild levels of skin pain or itch are frequently experienced by patients, who rarely report them. There is a need for a better knowledge of sensitive skin because it can be the first level of small-fiber neuropathies.

Sensitive skin: A relevant syndrome, be aware

Sensitive skin is clinically defined by characteristic sensory perceptions including tightness, abnormal stinging, burning, tingling, pain and pruritus. Facial erythema may occur, and other body areas can be involved. Sensitive skin affects extremely the quality of life. According with the International Forum for the Study of Itch (IFSI), sensitive skin is defined as a syndrome. The unpleasant sensations described are in response to stimuli that normally should not provoke such sensations. Moreover, these unpleasant sensations cannot be explained by any skin disease. Sensitive skin is always considered when any new consumer health, cosmetic or household product is introduced in the market. Once sensitive skin is recognized, it is mandatory to identify specific triggers that commonly induce symptoms and even cutaneous visible signs. Sensitive skin syndrome can be exacerbated by an allergic setting and environmental factors (cold, hot, dryness, pollution, wind, chemicals ...), a source of intolerance and unpleasant sensations. Cosmetics are the main triggering factors of sensitive skin according to patient's reports. The presence of potentially irritant substances in their composition increases the clinical expression of symptoms. As sensitive skin is frequent, and it is increasing based on the current development of cosmetic use worldwide, there is a need to develop better skin care products. The continuous research of active and safe skin care products to prevent and treat sensitive skin is extremely welcome.

Characteristics, mechanism, and management of pain in atopic dermatitis: A literature review

BACKGROUND

Atopic dermatitis (AD) is a chronic, pruritic, immune-mediated inflammatory disease. Developments in basic science and clinical research have increased our understanding of AD. Although pain as a symptom of AD is underemphasized in previous studies, multiple researchers address pain as a frequent burden of AD. However, the exact role of pain in AD is not fully understood.

AIMS

Our review aimed to summarize the current evidence focusing on characteristics, mechanism, and management of pain in AD.

MATERIALS & METHODS

We conducted a thorough literature review in the PubMed database to figure out different aspects discussing pain in AD, including pain symptoms, burden, the relationship between pain and itch, mechanism, and pain management in AD.

RESULTS AND CONCLUSION

AD patients affected by skin pain vary from 42.7%-92.2% with remarkable intensity and heavy burden. Skin pain and itch interacted both in symptoms and mechanisms. Atopic skin with the impaired barrier, neurogenic inflammation mediators, peripheral and central sensitization of pain may possibly explain pain mechanism in AD. Future research is needed to clarify the commonality and disparity of pain and itch in AD in order to seek efficacious medications and treatment.

Burden of Sensitive Skin (BoSS) Questionnaire and Current Perception Threshold: Use as Diagnostic Tools for Sensitive Skin Syndrome

The assessment of sensitive skin syndrome, characterized by subjective unpleasant sensations, remains a challenge, since there is no international consensus on the best diagnostic tools. This study evaluated the combination of the Burden of Sensitive Skin (BoSS) questionnaire and the current perception threshold as diagnostic tools for sensitive skin syndrome, and the relationship between BoSS and the subjects’ smoking status, phototype and skin type. A total of 100 women completed the BoSS questionnaire, and current perception threshold was measured on the face. The BoSS score was significantly higher in the self-reported sensitive skin group compared with the non-sensitive skin group (25.61 vs 14.05; p < 0.001), and in non-smokers vs smokers (23.00 vs 18.37; p < 0.05). In addition, the current perception threshold values were similar between the sensitive and non-sensitive groups. These results suggest that BoSS is a better diagnostic tool for sensitive skin syndrome than the current perception threshold, and that smokers less frequently have sensitive skin than do non-smokers.

Proposal of a self-assessment questionnaire for the diagnosis of sensitive skin

Background

Sensitive skin is very common and distressing. Its diagnosis may be difficult with the tools/methods available at the moment.

Aims

To assess the reliability of a self‐assessment questionnaire for the diagnosis of sensitive skin, using the results of lactic acid stinging test (LAST) as a reference for the identification of subjects suffering from this condition. A further objective was to identify the questionnaire cutoff score that better discriminates between subjects with or without sensitive skin.

Patients/methods

Among the adult volunteers included in this observational, cross‐sectional study, both LAST‐positive subjects, who were considered as having sensitive skin (“patients”), and negative ones (“controls”) completed the questionnaire. It consisted of a part for self‐assessing and quantifying (0–10) sensitive skin and another one that included 10 items, each referring to a specific, potentially triggering stimulus. A cumulative score (questionnaire‐based skin sensitivity score, 0–10) was calculated from the sum of all items considered capable of triggering unpleasant skin sensations in real‐life experience.

Results

One hundred and sixty‐two subjects were enrolled, 102 patients and 60 controls; 98 subjects thought they had sensitive skin. The mean questionnaire‐based skin sensitivity score was significantly higher among patients than controls and correlated with skin sensitivity self‐assessments. A cutoff value of 3 was set for the identification of LAST‐positive subjects, with 79% accuracy.

Conclusions

The study self‐assessment questionnaire seems to be a reliable tool for diagnosing sensitive skin in clinical practice. These results led us to identify a numerical cutoff for detecting propensity to experience sensitive skin.

A Survey to Identify Determinants That Influence Self-Perceived Sensitive Skin in a British Population: Clues to Developing a Reliable Screening Tool for Sensitive Skin

Background

Skin sensitivity characteristics and triggers have been identified in populations in previous studies. However, few have compared these characteristics among self-reported sensitive skin.

Objective

The aim of the study was to evaluate and compare specific intrinsic and extrinsic triggers of skin sensitivity between individuals with self-reported sensitive skin and non-sensitive skin.

Methods

A systematic literature review was undertaken to identify intrinsic and extrinsic factors associated with sensitive skin. A 167-item survey was developed on the basis of the literature review. The survey was completed online by a sample of adult participants drawn from the general United Kingdom population. Participants also completed sociodemographic and self-reported health questions.

Results

A total of 3050 surveys were completed: 1526 participants with self-reported skin sensitivity and 1524 participants not reporting skin sensitivity. There was a decrease in self-reported skin sensitivity with increasing age (p<0.05), and proportionally more women reported sensitive skin. Smoking also led to a higher frequency of sensitive skin. All signs and symptoms of sensitive skin, such as itch, dryness/flakiness, roughness and flushing/blushing were more commonly reported by those with self-reported sensitive skin. These were frequently reported in association with external factors (cold/windy weather, clothes and fabrics), as well as internal factors such as pre-existing skin conditions and atopy.

Conclusion

The study evaluated self-reported sensitive skin against a non-sensitive skin in order to identify common inherent and external triggers to distinguish between these groups in a large general population study in the United Kingdom. The key symptoms and signs of this syndrome identified in the literature were confirmed to be reported significantly more when compared with those without sensitive skin. However, no correlation or pattern of symptomology could be identified, reinforcing the complexity of this condition. Given the strong differentiation from the non-sensitive group, the results of this research could be utilised for the development of a clinically meaningful screening tool.

Understanding the Sensitive Skin Subject to Achieve a More Holistic Diagnosis

Sensitive skin Syndrome (SSS) is a complex global clinical phenomenon that is defined by the self-reported presence of different sensory perceptions, including tightness, stinging, burning, tingling, pain and pruritus and often without objective signs. Due to the subjective nature of this clinical condition, the diagnosis is complex and there is often a disconnect between what subjects feel and what medical professionals can observe. This chapter reviews the known underlying physiology, some of the triggering factors associated with SSS, co-morbidities as well as the psychological impact on individuals suffering from this condition. The goal is to bridge the gap between the physicians’ understanding and the subjects’ perceptions of this real-life condition that affects so many.

Use of Cosmetic Products in Real Life by Women with Facial Sensitive Skin: Results from an Exposure Study and Comparison with Controls

Triggering factors of sensitive skin are supposed to be physical, chemical (cosmetics, water, and pollutants), and occasionally psychological (stress). A recent meta-analysis showed that the most important triggering factor declared by subjects is the use of cosmetics. This study was designed to compare the consumption of cosmetic products in women with sensitive skin and controls. After a dermatological examination, women between the ages of 18 and 65 years with or without sensitive skin were recruited. They completed different questionnaires about the presence of sensitive skin and use of 28 cosmetics that could be applied on the face. The amount per application was recorded for all products used at least once a week on the face. In total, 160 women were included, with a mean age of 41 ± 13 years. Two groups of 40 women were created based on the sensitive scale (SS-10 score), with the lowest SS-10 scores (nonsensitive skin group) and the highest SS-10 score (sensitive skin group). The number of products used daily was similar in the 2 groups. Women with sensitive skin were significantly more frequent users of liquid soap/soap-free gel cleansers than those without sensitive skin (70 vs. 43%). There was no difference concerning the frequency of use of products in the 2 groups. Concerning the amount of product used by application, women with sensitive skin used twice as much cream per application compared with the women without sensitive skin: 511 ± 438 μg versus 290 ± 203 μg (p = 0.039). Concerning the composition of the cosmetic products used, the only difference concerned phenoxyethanol, which was more often present in the moisturizer of women without sensitive skin (66.7%) than in those with sensitive skin (32.4%) (p = 0.007). Women with sensitive skin were more likely to buy products recommended for sensitive skin by manufacturers. The relationship of causality between the use of cosmetics and sensitive skin cannot be established. Women with sensitive skin used different cosmetic products than women without sensitive skin. Women with sensitive skin used a higher amount of moisturizer, used products recommended for sensitive skin, and bought more cosmetic products at pharmacies than supermarkets. We hypothesized that subjects with sensitive skin are looking for products that improve the sensation of skin sensitivity.

Sensitive Scalp: A Possible Association With the Use of Hair Conditioners

A sensitive scalp is defined by the occurrence of unpleasant sensations (tingling, burning, pain, pruritus) triggered by stimuli that should not cause such sensations. Environmental factors, particularly cosmetics, can be triggering factors. The aims of this study were to assess hair cosmetic product consumption in subjects with sensitive scalp and to perform a clinical evaluation of sensitive scalp. After a dermatological examination, women between the ages of 18 and 65 years with or without a sensitive scalp completed different questionnaires. Their use of hair cosmetics (frequency, amount per application) was recorded. A total of 160 women with a mean age of 41 years were included. Twenty-seven subjects presented with seborrheic dermatitis or psoriasis, so only 133 were included in the analysis. Five percent of the subjects declared they had a very sensitive scalp, 25% had a sensitive scalp, 38% had a slightly sensitive scalp, and 32% had a scalp that was not sensitive. The mean sensitive scalp score (3S) score was 3.7 ± 1.6 in the very sensitive scalp group, 3.6 ± 2.1 in the sensitive group, 1.2 ± 1.2 in the slightly sensitive group and 0.1 ± 0.4 in the non-sensitive group. Two groups were analyzed: the 56 subjects with a sensitive scalp (3S ≥ 2 score) and the 56 subjects with a null 3S score. In the sensitive scalp group, 89% suffered from itch, and 45% suffered from tingling. No parameter (hormonal status, smoking, age, phototype, BMI) was associated with the 3S score. No differences in the exposure to shampoos and masks between the two groups were noted. The exposure to hair conditioners was significantly higher in the sensitive scalp group than in the group without sensitive scalp. Itch is the main symptom of a sensitive scalp. The frequency of a sensitive scalp was lower than that previously described when the subjects with scalp dermatosis were excluded. The amount of hair conditioners used was significantly higher in subjects with sensitive scalp than in those without sensitive scalp, suggesting a possible link.

Sensitive Skins May Be Neuropathic Disorders: Lessons from Studies on Skin and Other Organs

Sensitive skin can be considered a neuropathic disorder. Sensory disorders and the decrease in intra-epidermal nerve ending density are strong arguments for small-fiber neuropathies. Sensitive skin is frequently associated with irritable bowel syndrome or sensitive eyes, which are also considered neuropathic disorders. Consequently, in vitro co-cultures of skin and neurons are adequate models for sensitive skin.

Correlations on Phenolic Screening Related to In Vitro and In Ovo Assessment of Ocimum basilicum L. Hydro-Alcoholic Extracts Used as Skin Active Ingredient

The current study was aimed to evaluate the phenolic composition parameters of two hydro-alcoholic extracts of Ocimum basilicum L. (OB) obtained from the aerial part (without leaves) and leaves, in order to determine their contribution to the antioxidant activity (AOA). Both hydro-alcoholic extracts have proven to be rich in polyphenolic compounds, flavonoids, flavonols and tannins. Therefore, the leaves’ extracts reveal an inhibition percentage of 89%, almost comparable with the standard reference (95%). To complete the toxicological profile, the study also assessed the potential cytotoxicity of basil hydro-alcoholic extracts on immortalized human keratinocytes (HaCaT), skin human fibroblasts (1BR3), mice epidermis (JB6Cl41-5a) and primary human melanocytes (HEMa) cells, correlated to A375 antitumor in vitro activity. The extracts did not induce significant cytotoxic effect on any of the selected normal cell lines but showed relevant activity on A375 cells. Considering the low values obtained regarding the irritative effects in the chorionallantoic membrane of the egg on blood vessels, we can emphasize that both extracts can be considered as biocompatible ingredients. Regarding the potential activity of hydro-alcoholic extracts on human skin, the decrease of erythema values after the application of extracts was a relevant observation which indicates the anti-inflammatory potential of Ocimum basilicum L.

Nationwide Survey and Identification of Potential Stress Factor in Sensitive Skin of Chinese Women

Purpose

Sensitive skin is characterized by uncomfortable sensations in response to a number of factors. We performed a large-scale study to investigate the prevalence of sensitive skin at all ages and the impacts of related factors across China.

Methods

A nationwide sampling of the Chinese population aged over 18 was conducted. Subjects were categorized into sensitive and non-sensitive groups, and critical differences between these two groups were investigated.

Results

In total, 22,085 questionnaires were collected from Chinese women with sensitive skin. The prevalence of sensitive skin is 49.6% and is associated with age, skin type, geographic area of subjects, and other factors. Heavy life stress and the application of several cosmetic products also affect the prevalence of sensitive skin.

Conclusion

Having a combination or oily skin type, living in the municipalities, being under heavy stress, and applying several cosmetic products will increase skin stress and contribute to the occurrence of sensitive skin.

An herbal cream reduces erythema of sensitive skin

BACKGROUND

Sensitive skin manifests itself as a syndrome defined by the occurrence of unpleasant sensations such as stinging, burning, and pruritus. Though not life-threatening, it can negatively impact the quality of people's lives because of symptoms and clinical signs. Although some skin care products can alleviate symptoms of sensitive skin, a product that can improve multiple abnormalities of sensitive skin are largely unavailable.

AIMS

To assess the efficacy of a newly developed herbal cream in reducing erythema.

METHODS

A randomized double-blind and self-controlled trial was carried out on a total of 35 volunteers. The test cream (A) was applied topically to one side of the face twice-daily, while the control cream (B) was applied to the other side of the face. Parameters were evaluated prior to, 14, and 28 days after topical applications. Primary endpoints included changes in erythema area, erythema index (EI), and a* value. Transepidermal water loss rates (TEWL), stratum corneum (SC) hydration, and lactic acid sting test (LAST) score, as well as the L* value, served as secondary endpoints.

RESULT

Treatments with either cream A or B markedly reduced erythema area, EI, and a* value. Significant reductions in both TEWL and L* value were also observed following topical applications of either cream A or B. Moreover, cream A decreased LAST score. Finally, the satisfaction rate of cream A was higher than that of cream B.

CONCLUSION

The new herbal cream improves cutaneous biophysical properties in subjects with sensitive skin, especially in reducing erythema.

Health-related quality of life in porphyria cutanea tarda: a cross-sectional registry based study

BACKGROUND

Porphyria cutanea tarda (PCT) is a rare, photosensitive disease characterized by skin fragility and blistering on sun-exposed areas. There is little previous research on how this condition affects health-related quality of life (HRQoL) and to the best of our knowledge this is the largest sample of PCT patients surveyed about their HRQoL. The aims of this study were to describe HRQoL, symptoms, susceptibility factors, disease activity and treatment in patients with PCT, and investigate the associations between these factors.

METHODS

This is a cross-sectional, retrospective study based on patient-reported outcome and laboratory data. The Norwegian Porphyria Centre diagnoses all patients with PCT in Norway, all of whom are invited to participate in the Norwegian Porphyria Registry. Between December 2013-2015, 111 patients received a postal questionnaire and invitation to participate.

RESULTS

Sixty-eight persons responded, with seven being excluded due to prolonged response time or missing information, resulting in 61 participants in the final analyses (55%). Median age was 60 years and 33 were female. We found a moderate negative relationship between the type and localisation of PCT symptoms and both mental (r = -.354 p < 0.01) and physical (r = -.441, p < 0.01) aspects of HRQoL. Participants who had started treatment when answering the questionnaire reported significantly better physical functioning and less bodily pain than those who had not started treatment. We did not observe an association between biochemical markers of disease activity and symptoms or HRQoL. Itching, a symptom that has received little attention in PCT was reported by 59% of the participants.

CONCLUSIONS

Our results show that reduced HRQoL is associated with more symptoms and not having started treatment. PCT is a rare disease, and there is a need for the development of best-practice guidelines to facilitate good patient care.

Efficacy and Tolerability of Phototherapy With Light-Emitting Diodes for Sensitive Skin: A Pilot Study

Sensitive skin (SS) syndrome is defined by the occurrence of unpleasant sensations in response to stimuli that should normally not induce such sensations. It affects ~50% of women and 40% of men and can impact the quality of life. There is no consensus on therapeutic management. Phototherapy by light-emitting diodes (LEDs) is increasingly being used in dermatology for various inflammatory skin disorders with significant reduction in SS-10 and good tolerability. A Korean study suggested its efficacy in alleviating SS symptoms associated with other facial diseases. Our objective is to obtain preliminary data on the efficacy of phototherapy with LEDs for alleviating SS symptoms and increasing tolerance in subjects with SS that is not associated with other facial skin disorders. This monocentric pilot study included 30 subjects with SS who had a Sensitive Scale-10 score ≥40. The treatment consisted of red LED light exposure twice a week until significant reduction in SS-10 with a maximal treatment length of 8 weeks. The primary outcome was defined by a 60% decrease in the SS-10 score compared to the baseline.

Results: Thirty subjects were included; 83% were women, and the mean age was 28.9 years. Two participants were considered lost to follow-up. The cheeks (90%) and the nose (70%) were the most frequently involved parts of the face. Cold, heat, temperature variation, water and sun were the most frequent triggering factors. Twenty-eight subjects (93.3%, 95% CI 77.9 to 99.2%) achieved the primary outcome. Significant reduction in SS-10 was achieved in 77% of subjects in six sessions or fewer. The mean (SD) SS-10 scores were 54.7 (12.1) at inclusion, 14.4 (6.0) at the last session and 13.9 (7.5) 2 months after the last session, suggesting that the benefits persist for a few weeks. Two side effects were reported: both were allergic reactions to the nickel contained in the protective goggles. This pilot study had a small sample size and no control group. LEDs were effective in treating SS in all 28 subjects who completed the study in accordance with the protocol, and the benefits persisted for 2 months after the last LED therapy session.

Baumann Skin Type in the Korean Male Population

Background

Research into the Baumann skin type (BST) has recently expanded, with growing interest in the development of an efficient and effective skin type classification system for better understanding of this skin condition.

Objective

We aimed to identify male-specific skin type characteristics with investigation into the distribution of BST by age and region in the Korean male population and to determine the intrinsic and extrinsic factors related to skin type.

Methods

A questionnaire was administered to collect information about age, region, working behavior, drinking behavior, smoking behavior, usual habit of sun protection, medical history, and the BST which consisted of four parameters; oily (O) or dry (D), sensitive (S) or resistant (R), pigmented (P) or non-pigmented (N), and wrinkled (W) or tight (T).

Results

We surveyed 1,000 Korean males aged between 20 and 60 years who were divided equally by age and region. Of the total respondents, OSNW type accounted for the largest percentage and ORPW type the lowest. In terms of Baumann parameters, O type was 53.5%, S type was 56.1%, N type was 84.4% and W type was 57.5%. Several behavioral factors were found to have various relationships with the skin type.

Conclusion

The predominant skin type in the Korean male respondents was OSNW type, and the distribution of skin types with regards to age and region was reported to be distinct. Therefore, skin care should be customized based on detailed skin types considering the various environmental factors.

Skin sensitivity evaluation: What could impact the assessment results?

BACKGROUND

For the evaluation results of skin sensitivity, such as clinical parameters, stinging test records and biophysical assessments dates might be impacted by many factors, the influence factors need to be further explored, and the skin sensitivity evaluation process and methodology needed distinction and normalization. In this study, we investigated the changes of sensitive skin indexes and lactic acid stinging test results in different seasons, facial regions, skin photo-type, and living habits.

METHODS

Twenty-four healthy subjects had completed this study. Lactic acid stinging test was performed in different seasons. Transepidermal water loss (TEWL), skin hydration, sebum secretion, and pH were measured in an environment-controlled room. Correlations between stinging responses, skin biophysical parameters, and sensitive skin inducements in different seasons were statistically analyzed.

RESULTS

Skin TEWL, hydration, sebum secretion, and pH values on different facial parts were various. Two-way correlation analysis between the results of lactic acid stinging test in different seasons and the sensitivity factors showed differences between summer, autumn, and winter. The mean scores of lactic acid stinging test increased in autumn. Linear regression analysis of skin sensitivity factors in type III and type IV photobiology skin found that the frequency of sleeping time and eating spicy food in the past of week could infect the sensitive skin evaluation dates statistically (P < .05).

DISCUSSION/CONCLUSIONS

Skin sensitivity assessment results were impacted by seasonal transformation, living habits and customs, and facial regions. These indicted that we should consider above interfering factors when evaluated the skin sensitivity for getting more precise dates.

Gender-related characterization of sensitive skin in normal young Chinese

BACKGROUND

While clinical signs, symptoms, as well as etiology of sensitive skin in general populations have been extensively studied over the last decades, characteristics of sensitive skin in normal subjects, particularly gender-related characteristics, still remain unknown.

OBJECTIVE

In the present study, we characterize facial sensitive skin in normal young Chinese.

SUBJECTS AND METHODS

A questionnaire was given to each participant aged 10-30 years. Clinical signs, symptoms, and associated trigger factors of facial sensitive skin were compared in normal young Chinese males versus females.

RESULTS

After excluding subjects with pre-existing skin disorders, 475 females and 429 males out of 954 responders were included in the analyzes. Prevalence of self-reported facial sensitive skin was significantly higher in females than in males. Yet, while more females experienced various symptoms, symptoms were more severe in males than in females. However, both the prevalence and severity of clinical signs were similar in females and males. Skin care products appeared to be the major contributors to facial sensitive skin in both genders. Moreover, it appeared that females were more sensitive to environmental factors such as low humidity and sun-exposure while males were more sensitive to emotional factors. Taken together, these results demonstrate that characteristics of sensitive skin are associated with gender, while the underlying mechanisms remain to be explored.

CONCLUSIONS

There are gender differences in prevalence, symptoms, and trigger factors of facial sensitive skin in normal young Chinese.

Itch Processing in the Skin

Itching can result from activity of specialized primary afferent neurons (“pruriceptors”) that have been shown to express certain molecular markers such as B-type natriuretic peptide and several members of the Mrgpr-family in rodents. On the other hand, neurons involved in pain processing (“nociceptors”) can also provoke itching when the activation site is restricted to an isolated tiny spot within the epidermis. Individuals classified as having sensitive skin report increased itching and pain sensations upon weak external stimuli that are not painful or itchy in the control group. Numerous possible factors could contribute to sensitive skin along the pathway of transduction of the external stimuli into peripheral neuronal signals, followed by neuronal processing, finally resulting in the perception: (a) reduced local protective factors leading to impaired skin barrier function, (b) increased production of excitatory skin mediators, (c) sensitized peripheral neurons, (d) facilitated spinal and central processing, and (e) reduced descending inhibition from the central nervous system. For all of those pathophysiological mechanisms there are clinical examples such as atopic dermatitis (a,b,c), neuropathic itching (c,e), and restless leg syndrome (d,e). However, none of these factors have been directly linked to the occurrence of sensitive skin. Moreover, individuals reporting sensitive skin are heterogeneous and a subpopulation with defined pathophysiology has not yet been identified. Given that the condition is reported in about 50% of women, and thereby includes many healthy individuals, it appears problematic to assign a definitive pathophysiological mechanism to it.

Association between lactic acid sting test scores, self-assessed sensitive skin scores and biophysical properties in Chinese females

Background

Lactic acid sting test (LAST) is a classical method to identify sensitive skin. However, some subjects with self‐perceived sensitive skin are negative for LAST.

Objective

To determine whether LAST scores are associated with specific phenotype of sensitive skin.

Methods

A total of 292 subjects with self‐perceived sensitive skin were enrolled in this study. The Sensitive Scale was used to evaluate the severity of burning, stinging, itching, tautness, erythema and scaling based on 0–10 scale scores. In addition to the assessment of LAST scores, epidermal biophysical properties were measured using an MPA system.

Results

The Sensitive Scale scores of stinging, itching, tautness and scaling were significantly different between the LAST‐positive and ‐negative groups. However, burning and erythema scores did not differ between the LAST‐positive and ‐negative groups. LAST scores were positively correlated with the Sensitive Scale scores for stinging, itching, tautness and scaling, but not for burning and erythema scores. Moreover, LAST scores negatively correlated with stratum corneum hydration, but positively with transepidermal water loss (TEWL) rates.

Conclusions

Lactic acid sting test scores positively correlated with TEWL rates. LAST scores could be used to identify subjects with sensitive skin characterized mainly by stinging and itching, but not those mainly by burning and erythema.

Role of Keratinocytes in Sensitive Skin

Sensitive skin is a clinical syndrome defined by the occurrence of unpleasant sensations such as burning, stinging, tingling, pricking, or itching in response to various normally innocuous physical, chemical, and thermal stimuli. These particular symptoms have led the consideration of a potential dysfunction of the intra-epidermal nerve fibers (IENF) that are responsible for pain, temperature, and itch perception. This neuronal hypothesis has just been reinforced by recent studies suggesting that sensitive skin could become assimilated to small fiber neuropathy. Meanwhile, the involvement of keratinocytes, the pre-dominant epidermal cell type, has so far mainly been considered because of their role in the epidermal barrier. However, keratinocytes also express diverse sensory receptors present on sensory neurons, such as receptors of the transient receptor potential (TRP) family, including Transient Receptor Potential Vallinoid 1 (TRPV1), one of the main transducers of painful heat which is also involved in itch transduction, and Transient Receptor Potential Vallinoid 4 (TRPV4) which is depicted as a heat sensor. While TRPV1 and TRPV4 are expressed both by sensory neurons and keratinocytes, it has recently been demonstrated that the specific and selective activation of TRPV1 on keratinocytes is sufficient to induce pain. Similarly, the targeted activation of keratinocyte-expressed TRPV4 elicits itch and the resulting scratching behavior. So, contrary to classical conception, the IENF are not the exclusive transducers of pain and itch. In light of these recent advances, this review proposes to consider the putative role of epidermal keratinocytes in the generation of the unpleasant sensations characteristic of sensitive skin syndrome.

The Prevalence of Sensitive Skin

Sensitive skin has been described as unpleasant sensory responses to stimuli that should not provoke such sensations. Objectively measurable signs of irritation are not always present in individuals with sensitive skin, however, subjective sensory effects such as, itching, burning, stinging, tightness, and dryness, are consistently present. Given the subjective nature of the phenomenon known as sensitive skin, surveys have been a popular approach to evaluating the prevalence of this condition among the general population, and a number of them have been conducted worldwide. Overall, ~60–70% of women and 50–60% of men report having some degree of sensitive skin. However, there are differences between populations in various geographies, and perceptions of sensitive skin at specific anatomic sites. This article is a review of survey data on the prevalence of self-declared sensitive skin in various geographies, among different gender and age groups, and at various anatomic sites. In addition, we review the factors that may contribute to sensitive skin, and the physiological characteristics associated with this condition, including impaired barrier function and heightened neural reactions.

Association of sensitive skin with sensitive corneas and sensitive eyelids

BACKGROUND

Sensitive scalp or irritable bowel syndrome has been previously shown to be associated with sensitive skin. We wondered whether sensitive eyelids and sensitive eyes could also be associated with sensitive skin.

METHODS

A cross-sectional epidemiological study was carried out on a representative sample of French people, according to the quota method, using a questionnaire.

RESULTS

A total of 2048 subjects were included in the present study. Notably, 52.2% declared sensitive eyes, which was more frequent in women than in men. The subjects who reported sensitive eyes were more numerous according to the severity of skin sensitivity, the severity of sleep disorders and the presence of bright eyes. More than half of the subjects with sensitive eyes thought that they were sensitive to sun exposure, dust, computer or touch pads or dry air. The presence of sensitive eyelids was reported by 18.65% (more frequent in women) and was associated with sensitive skin and sensitive eyes, sun exposure and exposure to dust.

CONCLUSION

This study is the first to investigate sensitive eyelids or sensitive eyes. Sensitive eyelids can be considered a localization of sensitive skin. The concept of sensitive eyes is not commonly used by ophthalmologists and remains to be more precisely defined.

Development and validation of a new tool to assess the Burden of Sensitive Skin (BoSS)

BACKGROUND

Sensitive skin usually manifests itself as unpleasant sensations and sometimes erythema. There are various triggering factors for this condition. Although sensitive skin may alter quality of life, its burden has not yet been explored.

OBJECTIVE

The aim of this study was to develop and validate a specific sensitive skin burden questionnaire called the BoSS (Burden of Sensitive Skin).

METHODS

A conceptual phase was developed, followed by a development phase, external validation, psychometric analysis, test-retest analysis and, finally, a translation, cross-cultural adaptation and cognitive debriefing.

RESULTS

A total of 6471 individuals participated in the study (4614 people in the validation study). The dimensionality of items was evaluated using factor analyses, suggesting three dimensions (self-care, daily life and appearance). Unidimensionality was confirmed by higher order factor analysis. The overall Cronbach's α coefficient was high, and intradimensional coherences all demonstrated good reliability. The final instrument consisted of 14 items. The test-retest reliability demonstrated very good reproducibility. The intraclass correlation of each dimension was high. External validity was confirmed by the correlation coefficients of the BoSS vs. those of the SF-12 and the DLQI assessment tools.

CONCLUSION

BoSS is the first reliable tool to assess the burden of sensitive skin.