Sensitivity to change of the Dermatology Life Quality Index in adult females with facial acne vulgaris: a validation study.

BACKGROUND: The postadolescent form of acne papulopustulosa, also referred to as 'acne tarda' can have substantial negative impact on Quality of Life, especially in adult female patients. OBJECTIVE: Although the Dermatology Life Quality Index (DLQI) is widely used, empirical evidence about its performance in adult female acne patients is lacking. METHODS: In this prospective cohort study, we have investigated the sensitivity to change of the DLQI in 53 female adult acne patients with mild to moderate facial acne treated with azelaic acid (AzA) 15% gel twice daily over 24 weeks. RESULTS: Mean Investigator Static Global Assessment (ISGA) score was 2.3 (SD 0.5) at baseline and ranged from 0.9 (SD 0.3) to 2.1 (SD 0.4) at the end of the study in the 'Highly Improved' and 'Unchanged' responder groups respectively. The mean baseline DLQI score was 5.1 (SD 4.2). The Effect Size in the responder group 'Highly Improved' was 0.66; in group 'Improved' 0.62 and 0.23 in group 'Unchanged'. At the end of study, the mean DLQI score ranged from 1.1 (SD 1.5) in the 'Highly Improved' group to 3.7 (SD 6.0) in the 'Unchanged' group. CONCLUSION: The results support the sensitivity to change of the DLQI in this population.

Follicular fluorescence quantity to characterize acne severity: a validation study.

BACKGROUND: Porphyrins are native fluorophores in the follicle openings, visible under ultraviolet-A light. Acne severity might be associated with increased Propionibacterium acnes colonization and porphyrin production. Aim of this study was to investigate whether the parameter fluorescence quantity can be used to measure acne severity. METHODS: A validation study was conducted in 24 patients with acne using split-face design. Acne severity was measured using Investigator Static Global Assessment scores and lesion counts. Reliability, construct validity and sensitivity to change in fluorescence quantity were investigated. RESULTS: Mean baseline Investigator Static Global Assessment score was 2.7 (SD 0.1). Mean baseline fluorescence quantities were 24.8 (SD 4.0) on the cheek and 20.3 (SD 4.6) on the chin. On day 25, values ranged from 6.0 (SD 6.0) to 18.1 (SD 18.4) on the cheek and from 2.6 (SD 4.4) to 14.7 (SD 16.2) on the chin. The intraclass correlation coefficients of fluorescence quantity ranged from 0.513 to 0.987. Effect sizes for fluorescence measurements were highest on the chin and cheek ranging from 0.24 to 0.77 and 0.32 to 0.75, respectively. CONCLUSION: Fluorescence quantity indicates acne severity, especially on the inner cheek and chin areas. Fluorescence quantity is reliable but is not as sensitive as manual lesion counting.

The skin barrier function: differences between intrinsic and extrinsic aging.

AIM: Transepidermal water loss (TEWL), stratum corneum hydration (SCH), and the skin surface pH are important parameters to characterize the skin barrier function. The aim of this exploratory study was to compare TEWL, SCH and skin surface-pH on sun-protected versus sun-exposed skin areas in relation to age. METHODS: Twenty four female subjects with healthy skin were recruited in three age groups. Lifetime sun exposure was assessed using a questionnaire. TEWL, SCH, and skin surface pH were measured on the right upper inner arm, right mid-volar forearm and right dorsal forearm under standardized conditions. RESULTS: Mean ages (SD) of the three age groups were 33.5 (2.1), 55.4 (2.7), and 76.6 (1.9) years. There were no TEWL differences between the age groups on either skin area. Significantly lower TEWL values were observed on the dorsal forearm compared to the other skin areas (P<0.05). Mean SCH was comparable between the age groups. Higher SCH values were measured on the volar forearm (P<0.05). Skin surface pH on the upper inner arm was significantly higher in the aged group (P=0.023). The dorsal forearm skin had a lower pH than the upper inner arm. CONCLUSION: There seem to be minor changes of TEWL and SCH, but a clear increase of skin surface pH during the course of life. Differences between intrinsically and extrinsically aged skin areas were observed, but results provide no clear evidence for an impairment of the skin barrier function due to photodamage.

Skin response to sustained loading: A clinical explorative study.

BACKGROUND: Severe illness, disability and immobility increase the risk of pressure ulcer development. Pressure ulcers are localized injuries to the skin and/or underlying tissue as a result of long enduring pressure and shear. Little is known about the role of the stratum corneum and the upper skin layers in superficial pressure ulcer development. OBJECTIVES: To investigate possible effects of long enduring loading on the skin barrier function under clinical conditions at two pressure ulcer predilection sites. METHODS: Under controlled conditions 20 healthy females (mean age 69.9 (3.4) years) followed a standardized immobilization protocol of 90 and 150 min in supine position wearing hospital nightshirts on a standard hospital mattress. Before and immediately after the loading periods skin surface temperature, stratum corneum hydration, transepidermal water loss and erythema were measured at the sacral and heel skin. RESULTS: Prolonged loading caused increases of skin surface temperature and erythema at the sacral and heel skin. Stratum corneum hydration remained stable. Transepidermal water loss increased substantially after loading at the heel but not at the sacral skin. CONCLUSIONS: Skin functions change during prolonged loading at the sacral and heel skin in aged individuals. Accumulation of heat and hyperaemia seem to be primarily responsible for increasing skin temperature and erythema which are associated with pressure ulcer development. Increased transepidermal water loss at the heels indicate subclinical damages of the stratum corneum at the heel but not at the sacral skin during loading indicating distinct pathways of pressure ulcer development at both skin areas.

Quantifying dyspigmentation in facial skin ageing: an explorative study.

OBJECTIVE: The skin melanin system is affected by ageing, resulting in dyspigmentation with associated clinical and psychosocial consequences. In dark skinned phenotypes, broad evidence is available, whereas little is known about pigmentary changes in fair-skinned Caucasians. The objective of this study was to investigate age-related changes in facial pigmentation and dyspigmentation in subjects of skin phototypes II-III and to develop and test parameters for quantifying dyspigmentation. METHODS: Twenty-four skin healthy female subjects were recruited in three distinct age groups (30-40, 50-60, 70-80 years). Skin colour was measured by Mexameter and Chromameter. Skin dyspigmentation was measured by clinical evaluation and newly developed image-processing parameters on the cheeks and the forehead. The reliability of the clinical evaluation was investigated by intraclass correlation coefficients between three raters, and the validity of the dyspigmentation parameters was analysed by bivariate correlations with related measures. RESULTS: Skin lightness decreased with increasing age. Clinical dyspigmentation scores showed positive associations with chronological age ranging between 0.452 and 0.606. RBX(®) -Brown transformation-based hyperpigmentation and hypopigmentation indices increased with age, whereas the overall pigmentation intensity decreased with age at the cheeks. The image analysis-based parameters showed strong associations with the clinical scores and related measurements. CONCLUSION: We demonstrated age-related changes in the facial colour and dyspigmentation of fair-skinned Caucasian females. An increase in dyspigmentation was found by clinical scoring and the RBX(®) -Brown transformation-based pigmentation indices. The validity of hyper- and hypopigmentation indices and overall pigmentation intensity was supported. The RBX(®) transformation-based pigmentation indices might be applied in future studies to complement or substitute clinical evaluation.

Reliability and validity of two in vivo measurements for skin surface topography in aged adults.

BACKGROUND: The non-contact optical methods phaseshift rapid in vivo measurement of skin (PRIMOS) and surface evaluation of living skin (SELS) are widely applied for measuring skin surface topography. The aims of the present study were to evaluate reliability and validity of these methods and to compare skin roughness intraindividually. METHODS: SELS and PRIMOS measurements were performed on four skin areas of the left and right volar forearms in 12 healthy elderly subjects. Reliability and correlations were analyzed for Visioscan® and PRIMOS roughness parameters. Student's t-tests for estimating differences between contralateral volar forearm sites were applied. RESULTS: ICC coefficients of the Visioscan® roughness estimates ranged between 0.50 and 0.95 and of the PRIMOS measurements between 0.01 and 1.00. The Visioscan® parameters SEr, SEsm, Rmax, and Rz, and the PRIMOS parameters Ra, Rz, Smax, Wt, and Sz showed most significant correlations with each other and to additional roughness parameters. Mean roughness differences between contralateral forearm skin areas ranged between 0.0 (SEsc) and 6.7 (Rmax). CONCLUSIONS: The Visioscan® parameters SEr, Rmax, and Rz showed most reliable and valid values and were largely comparable on contralateral forearm skin sites in elderly subjects. Rmax, Rz, and Ra should be preferred for measuring skin surface topography with PRIMOS.

Relation between skin micro-topography, roughness, and skin age.

BACKGROUND: The topography of the skin surface consists of lines, wrinkles, and scales. Primary and secondary lines form a network like structure that may be identified as polygons. Skin surface roughness measurements are widely applied in dermatological research and practice but the relation between roughness parameters and their anatomical equivalents are unclear. This study aimed to investigate whether the number of closed polygons (NCP) per measurement field can be used as a reliable parameter to measure skin surface topography. For this purpose, we analysed the relation between skin surface roughness parameters and NCP in different age groups. METHODS: Images of the volar forearm skin of 38 subjects (14 children, 12 younger, and 12 older adults) were obtained with the VisioScan VC98. The NCP was counted by three independent researchers and selected roughness parameters were measured. Interrater reliability of counting the number of closed polygons and correlations between NCP, roughness parameters, and age were calculated. RESULTS: The mean NCP/mm² in children was 3.1 (SD 1.1), in younger adults 1.0 (SD 0.7), and in older adults 1.0 (SD 0.9). The interrater reliability was 0.9. A negative correlation of NCP/mm² with age was observed, whereas measured roughness parameters were positively associated with age. NCP/mm² was weakly related to skin roughness. CONCLUSION: The NCP/mm² is a reproducible parameter for characterizing the skin surface topography. It is proposed as an additional parameter in dermatological research and practice because it represents distinct aspects of the cutaneous profile not covered by established roughness parameters.