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.

INTRODUCTION: Un questionnaire d'auto-évaluation récemment proposé visant à diagnostiquer la peau sensible a fourni des résultats prometteurs dans une population relativement petite. Les principaux objectifs étaient: (i) d'évaluer la fiabilité du questionnaire susmentionné dans une population plus large et de vérifier la valeur du cut-off précédemment trouvé pour prédire la sensibilité cutanée (définie comme la positivité au LAST, de l'anglais « test de piqûre d'acide lactique ¼), et (ii) de définir une formule qui donne la probabilité d'un résultat LAST positif. MÉTHODES: Des volontaires adultes ont été inclus dans cette étude observationnelle, transversale et étendue. Les sujets LAST-positifs, qui étaient considérés comme ayant la peau sensible ('patients'), et les sujets négatifs ('témoins') ont rempli le questionnaire, qui concernait la sensibilité aux possibles déclencheurs de sensations cutanées désagréables dans la vie réelle. Un score cumulatif (score de sensibilité cutanée basé sur un questionnaire, 0-10) a été calculé à partir de la somme de tous les éléments. RÉSULTATS: Trois cent soixante-quatre sujets ont été recrutés, 214 patients et 150 témoins. Le résultat moyen de sensibilité cutanée basé sur le questionnaire était significativement plus élevé chez les patients que chez les témoins. En utilisant deux méthodes différentes, des valeurs seuils de 4 et 5 ont été définies pour l'identification des sujets LAST-positifs, avec une précision de 76,6% et 72,8%, respectivement. Les scores inférieurs à 4 ou supérieurs à 5 ont montré une valeur prédictive négative ou positive élevée (80% ou plus), respectivement. Les coefficients trouvés en différentes analyses pour chaque élément du questionnaire, sexe et âge nous ont permis de calculer la probabilité de positivité LAST avec une plus grande précision en tenant compte du « poids relatif ¼ de chaque facteur. CONCLUSIONS: Avec de faibles variations dans les résultats, le questionnaire d'auto-évaluation a confirmé sa fiabilité pour le diagnostic des peaux sensibles dans la pratique clinique.

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.

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.

Amelioration of lactic acid sensations in sensitive skin by stimulating the barrier function and improving the ceramide profile.

We determined whether compensating ceramides in the stratum corneum (SC) may ameliorate the impaired barrier function and subsequently attenuate the enhanced skin sensitivity. Treatment for 4 weeks with the ceramide complex cream or the placebo cream significantly ameliorated the intensity of lactic acid sensations in 39 female subjects with sensitive skin, the degree of which was attenuated to a greater extent at 1 week by the ceramide complex cream compared with the placebo cream. The amelioration of skin sensations was accompanied by a significant increase in total ceramide content in the SC elicited by the ceramide complex cream that was significantly more effective than the placebo cream at 4 weeks. Consistently, TEWL and conductance values were significantly decreased or increased at 1 and 4 weeks, respectively, to a greater extent by the ceramide complex cream than by the placebo cream. TEWL levels were significantly correlated with the increased levels of SC total ceramide in the ceramide complex cream-treated skin but not in the placebo cream-treated skin. Thus, the amelioration of lactic acid sensations by topical application of a ceramide complex cream, provides a deep insight into the pathophysiology of sensitive skin as a reduced barrier function-dependent sub-clinical sensory response.

Sensitive skin is highly frequent in extrinsic atopic dermatitis and correlates with disease severity markers but not necessarily with skin barrier impairment.

BACKGROUND: Sensitive skin is a condition of cutaneous hypersensitivity to environmental factors. Lactic acid stinging test (LAST) is commonly used to assess sensitive skin and composed of four distinct sensations (pain, burning sensation, itch, and crawly feeling). A link between sensitive skin and barrier dysfunction has been proposed in atopic dermatitis (AD) patients. However, clinical and laboratory factors that are associated with sensitive skin remain unelucidated. OBJECTIVE: To investigate relationship between sensitive skin and AD-associated markers. METHODS: Forty-two Japanese AD patients and 10 healthy subjects (HS) were enrolled. AD patients were divided into extrinsic (EAD; high IgE levels) and intrinsic (IAD; normal IgE levels) types. We conducted 1% LAST by assessing the four distinct sensations and calculated the frequencies of sensitive skin in EAD, IAD, and HS. We also performed clinical AD-related tests, including transepidermal water loss (TEWL), visual analogue scale (VAS) of pruritus, and quality of life, and measured laboratory markers, including blood levels of IgE, CCL17/TARC, lactate dehydrogenase (LDH) and eosinophil counts, and concentration levels of serum Th1/Th2 cytokines. Filaggrin (FLG) mutations were examined in 21 patients. These values were subjected to correlation analyses with each of the four sensation elements. RESULTS: According to the standard criteria for LAST positivity, the frequencies of LAST-positive subjects were 54.8% and 10.0% in AD and HS, respectively (P=0.014). EAD patients showed a significantly (P=0.026) higher frequency of positive LAST (65.6%) than did IAD patients (20.0%). Among the four LAST sensation elements, the crawly feeling and pain scores positively correlated with VAS of pruritus, total serum IgE, mite-specific IgE, CCL17/TARC, and/or LDH. There was no association of the LAST scores with serum Th1/Th2 cytokine levels. Notably, neither TEWL nor FLG mutations correlated with LAST positivity or any sensation scores. CONCLUSIONS: The frequency of sensitive skin is higher in EAD than in IAD. Sensitive skin is associated with AD severity, but not necessarily with barrier condition.

Relationship between transient receptor potential vanilloid-1 expression and the intensity of sensitive skin symptoms.

BACKGROUND: Sensitive skin (SS) is a hyper-reactive condition of the skin secondary to external factors, without objective signs of lesion. Its pathogenesis is still under investigation. Transient receptor potential vanilloid-1 (TRPV1) is a cation channel that responds to low pH and is related to nociception, neurogenic inflammation, and pruritus. AIMS: To determine the expression of TRPV1 in subjects with SS and correlate it with the degree of symptoms and skin pigmentation. PATIENTS/METHODS: We included 31 subjects self-diagnosed as having SS. Colorimetric values were obtained for assessment of skin phototype, and the lactic acid stinging test (LAST) was performed. Two skin biopsies from the nasolabial fold of each volunteer were obtained. Qualitative analysis of TRPV1 was carried out with immunohistochemistry. Quantitative analysis of TRPV1 was carried out with qRT-PCR. RESULTS: LAST was positive in 74% of the subjects, 56% of those having tan and brown skin. Immunohistochemistry staining for TRPV1 was greater in positive subjects (P = 0.03), but showed no correlation with the intensity of symptoms. Positive subjects also had higher TRPV1 mRNA expression compared to negative subjects (P < 0.001). This expression showed a positive correlation with the intensity of referred symptoms (R = 0.75, P < 0.001) and skin pigmentation (R = 0.63, P < 0.001). CONCLUSIONS: TRPV1 expression is upregulated in subjects with sensitive skin, and it correlates with the intensity of the symptoms. Our findings suggest a role for this receptor in the pathogenesis of sensitive skin syndrome.

CPT, the main test method of skin neuronal sensitivity.

BACKGROUND: Many scholars concentrate on skin barrier disruption of sensitive skin, but few focus on its increased neuronal sensitivity. OBJECTIVE: To study the possibility of using current perception threshold (CPT) measurement for the quantitative evaluation of skin neuronal sensitivity combined with stinging test. METHODS: The amount of 50 µL 10% lactic acid was applied on each side of the nasolabial fold at random. Subjects assessed stinging based on a 4-point scale at 30 s, 2.5 min and 5.0 min. CPT and transepidermal water loss (TEWL) were measured before and after stinging test. Subjects were divided into different groups based on their response to lactic acid. RESULTS: There was a positive correlation between CPTbefore and the sum of clinical scores (CSs). While the beginning time of stinging (BT) was shortened, the CPTbefore decreased and TEWL increased. CONCLUSION: Different degrees of skin susceptibility can be reflected by BT. CPT can be useful for the quantitative evaluation of skin neuronal sensitivity.

Ethnic differences in objective and subjective skin irritation response: an international study.

BACKGROUND: Due to global marketing in the cosmetics industry, it is important to assess ethnic population susceptibility when evaluating the safety of cosmetic products or chemicals. OBJECTIVES: To investigate ethnic variations in skin irritation response to positive irritants. METHODS: Clinical testing was performed in four countries on two ethnic groups - Asian and Caucasian. We performed patch tests on the subjects' back with 0.5% aqueous sodium lauryl sulfate (SLS) and 0.15% retinol prepared in 1,3-butylene glycol. Stinging tests were performed using 5% aqueous lactic acid and 0.001% (w/v) capsaicin prepared in 10% ethanol solution separately. RESULTS: The incidence of self-perceived skin sensitivity was similar in the two ethnic groups. However, the incidence of adverse skin reaction to cosmetics appeared significantly higher in Asian (33.0%) than in Caucasian subjects (11.3%). For standard positive irritants such as 0.5% aqueous SLS solution, Asian subjects showed significantly higher scores than Caucasian subjects. The incidence of positive reaction to the 0.15% retinol patch test tended to be higher in Asian than in Caucasian subjects. Our data also showed that neurosensitivity to 5% lactic acid and 0.001% capsaicin was higher in Asian than in Caucasian subjects. CONCLUSION: Although self-reported skin sensitivity does not appear to differ according to ethnicity, there are ethnic differences in objective and subjective skin irritation responses to several standard positive materials.

Relievene® SK: neuroimunomodulação para o tratamento dermocosmético da pele sensível / Relievene® SK: neuroimunomodulation for dermocosmetic treatment of sensitive skin

Pele sensível (PS) é definida como uma condição de tolerância reduzida ao uso freqüente ou prolongado de cosméticos e produtos de higiene pessoal, que apresenta desde sinais clínicos visíveis, como eritema, edema e descamação, até sinais neurossensoriais subjetivos de desconforto, como pinicamento, queimação, prurido, ressecamento e dor. A fisiopatologia da PS consiste em reação inflamatória decorrente de uma disfunção da barreira cutânea associada ao desequilíbrio da resposta neuroimunoendocrinológica da pele. Neste trabalho demonstramos os efeitos do produto Relievene® SK sobre a proteção do metabolismo celular, considerando as atividades adaptógena e neuroendócrina deste composto, bem como a melhora da função da barreira cutânea e da hiper-reatividade da pele em indivíduos com PS.