50-60 years old

1
QUANTIFICATION OF BODY SKIN AGING REQUIRES
MULTIPLE PARAMETERS
Crowther JM. Ph.D., Jarvis J., Matts PJ. Ph.D.
PG Beauty, Rusham Park, Whitehall Lane, Egham,
Surrey, United Kingdom, TW20 9NW
CONCLUSIONS
INTRODUCTION
OBJECTIVE
RESULTS
My skin is not the same now as it was when I
was younger, and Our skin changes as we
age., are phrases we often hear. But what is
the nature of this change, what effect does this
have on the perception of our skin and how can
these changes be quantified? It is well known
that as we age certain elements of our skin
change due to a combination of intrinsic (e.g.
reduced dermal elasticity and build up of fatty
tissue, combined with a reduction in collagen
regeneration) 1, 11, 10 and extrinsic factors
(for example exposure to smoke and sunlight) 2,
4, 5. Current research has concentrated on
specific aspects of the changes in skin as a
function of age 3, however the overall
perception of change is related to a number of
different aspects (i.e. mechanical, textural and
tonal) and on the effects these have on different
areas of the body. Certain parts of the body are
exposed to greater stress than others, either
mechanically (near joints) or environmentally
through sun exposure (backs of the hands and the
décolletage region of the chest) and would be
expected to show these signs of aging more than
other areas.
Visual changes Hydration, Chromophores Older
skin is visibly drier as measured using visual
dryness analysis, Figure 1, has higher melanin
and haemoglobin scores, combined with lower
collagen scores over all the body sites tested,
Figure 2. Note a lower L value indicates
increased melanin and haemoglobin, but decreased
collagen. Increased melanin, haemoglobin
combined with decrease collagen on aging has been
reported before in the literature 6,7. The
strongest differences were seen for the sites
exposed to both mechanical stresses and UV.
Biomechanical changes Elasticity Older skin has
reduced elasticity component corresponding to an
increased viscous component as shown by the
decreased R5 and R7 ratio values at all the high
stress body sites tested, Figure 3.
Demonstrate the benefit of measuring multiple
endpoints on several body sites when determining
the effects of aging on skin. Evaluate aging on
body sites typically exposed to mechanical
stresses compared to those exposed to extrinsic
stressors such as UV irradiation.

• Measuring multiple endpoints on several body
  sites provides a more coherent understanding of
  the effects of aging on skin.
• Statistically valid differences between young and
  old skin were observed with respect to dryness,
  uneven color, loss of elasticity and roughness.
• Body skin areas like the back of the hands and
  décolletage most often exposed to environmental
  stressors, such as UV exposure, show the most
  degree of aging.
• Measuring multiple endpoints on several body
  sites could provide a more coherent understanding
  when determining the efficacy of anti-aging body
  moisturizing formulations.
• References
• 1. Sorg O, Kuenzli S, Kaya G, Saurat J-H.
  Proposed mechanisms of action for retinoid
  derivatives in the treatment of skin aging, J
  Cosmet Dermatol 2005 4 237-244.
• 2. Leyden JJ. Clinical features of aging skin, Br
  J Dermatol 1990 122 (suppl 33) 1-3.
• 3. Zimbler MS, Kokoska MS, Thomas JR. Anatomy and
  pathophysiology of facial aging, Facial
  Rejuvenation Nonsurgical Modalities 2001 9(2)
  179-187.
• 4. Yin L, Moria A, Tsuji T. Skin premature aging
  induced by tobacco smoking the objective
  evidence of skin replica analysis, J Dermatol Sci
  2001 27 (suppl 1) S26-S31.
• 5. Kennedy C, Bastiaens MT, Bajdik CD, et al.
  Effect of smoking and sun on the aging of skin, J
  Invest Dermatol 2003 120 548-554.
• 6. Hillebrand GG, Miyamoto K, Schnell B,
  Ichihashi M, et al. Quantitative evaluation of
  skin condition in an epidemological survey of
  females living in northern versus southern Japan,
  J Dermatol Sci 2001 27 (suppl 1) S42-S52.
• 7. Akazaki S, Nakagawa H, Kazama H, et al.
  Age-related changes in skin wrinkles as assessed
  by a novel three-dimensional morphometric
  analysis, Br J Dematol 2002 147 689-695.
• 8. Li L, Mac-Mary S, Marsaut D, et al.
  Age-related changes in skin topography and
  microcirculation, Arch Dermatol Res 2006 297
  412-416.

demonstrates a significant difference from
the 20-30 year age group with plt0.05










To build a more coherent story of the effects of
age on highly stressed parts of the body, a
variety of techniques commonly used techniques
are available. These can be used to evaluate
signs of aging related to how people perceive
different aspects of their skin (colour, tone,
texture, firmness and dryness) and to
specifically evaluate more highly stressed areas.
Measuring multiple sites with various
methodologies could provide a more coherent
understanding of how these attributes may be
affected by the use of anti-aging moisturizing
products.
Figure 3. Skin elasticity values for the
different body sites as a function of age and
sample images.
Visual dryness images from young and old
skin 20-30 years old
50-60 years old
Texture changes Topography Skin roughness
increases measurably with age at all the high
stress body sites, Figure 4. This finding
correlates well with the reported literature
8,9.





demonstrates a significant difference from
the 20-30 year age group with plt0.05

METHODS
Figure 1. Visual dry skin values for the
different body sites as a function of age and
sample images.
Age study design Two female study populations
(n12) were chosen covering the age ranges of
interest - 20-30 and 50-60 years old. Subjects
were given 20 mins acclimatization and had
measurements taken from a number of high stress
body areas above the knees, the back of the
hands, the outside edge of the elbows and the
décolletage region of the chest. Measurements
were taken covering skin hydration, elasticity,
chromophore distribution and texture. All
measurements were carried out at 21ºC1ºC and
5010 humidity. ANOVA analysis was carried out
on all the data collected, and p values reported
at the 95 confidence level. Elasticity Visco-ela
stic response was measured using a commercially
available vacuum based system. 3 measurements
were taken at each site using a 2mm probe size
and 100mbar vacuum, and resultant R5 and R7
parameters averaged.
Texture Skin replicas were taken using silicone
resin and analysed on a commercial white light
fringe projection topographic measurements
device. Average roughness values (Ra) were
calculated using a star pattern and are reported
in µm. Chromophore distribution Contact
chromophore mapping and visual image analysis was
carried out to determine haemoglobin, melanin and
collagen distributions using commercially
available equipment. Scores are presented as
average L values from the image
analysis. Hydration An image was taken at each
site using a commercial near UV camera system and
image analysis used to determine percentage
visible dry skin.
Typical topographic skin images from young and
old skin
50-60 years old
20-30 years old





demonstrates a significant difference from
the 20-30 year age group with plt0.05

Melanin maps from young and old skin 20-30 years
old
50-60 years old


Figure 4. Average roughness values for the
different body sites as a function of age and
sample roughness images.

demonstrates a significant difference from
the 20-30 year age group with plt0.05



Overall results There is a very strong
correlation between subject age and the
differences observed with the techniques
employed. Areas more often exposed to
environmental stressors like UV appeared to show
the most consistent aging. This demonstrates that
to fully understand the aging process, especially
as it applies to high stress areas of the body,
it is helpful to employ a variety of
methodologies.







This work was funded by PG Beauty
Figure 2. Melanin, Haemoglobin and Collagen
values for the different body sites as a function
of age and sample melanin maps.