Research Article

Characterizing Facial Skin Ageing in Humans: Disentangling Extrinsic from Intrinsic Biological Phenomena

Table 2

Means and standard deviations of biophysical measurements and the difference between the age groups (ANOVA) for the right and left cheeks.

Young group
()
Midaged group
()
Old group
()
ANOVA
value
RightLeftRightLeftRightLeftRightLeft

Skin barrier
 TEWL12.9 (3.6)14.2 (3.5)8.9 (1.8)9.0 (2.0)9.8 (2.7)9.8 (2.4)0.0230.002
 SCH41.3 (11.1)45.6 (12.1)47.4 (9.4)46.0 (10.7)42.2 (10.7)42.1 (12.0)0.4630.760
 pH4.9 (0.6)4.5 (0.7)5.2 (0.5)4.9 (0.6)4.8 (0.4)4.8 (0.3)0.2360.323
Skin colour
65.8 (1.4)65.2 (1.8)64.6 (2.4)64.9 (1.8)62.2 (3.3)62.9 (2.0)0.0280.042
15.8 (1.3)15.9 (1.3)17.7 (2.1)17.8 (1.9)16.3 (1.8)17.0 (2.1)0.1010.118
Skin roughness
47.5 (7.3)47.4 (5.6)48.9 (5.4)49.6 (9.5)54.6 (8.8)54.3 (6.1)0.1400.175
63.4 (9.4)63.7 (7.0)64.4 (7.9)67.3 (12.4)73.7 (10.5)73.3 (7.8)0.0760.141
Skin elasticity
0.21 (0.04)0.21 (0.04)0.26 (0.09)0.25 (0.08)0.31 (0.09)0.29 (0.07)0.0710.074
0.06 (0.01)0.07 (0.02)0.1 (0.04)0.08 (0.03)0.13 (0.06)0.11 (0.04)0.0110.035
0.29 (0.02)0.28 (0.04)0.24 (0.04)0.26 (0.03)0.22 (0.09)0.25 (0.05)0.0820.246
0.04 (0.01)0.04 (0.01)0.05 (0.01)0.05 (0.01)0.06 (0.01)0.06 (0.01)0.0040.011

TEWL: transepidermal water loss (g/m²/h); SCH: stratum corneum hydration (arbitrary units); : luminance; : yellowness; : mean depth of roughness (µm); : maximal roughness (µm); : structural extensibility (mm); : residual skin deformation (mm); : elastic recovery (ratio); : immediate elasticity (area).