STUDY Improvement of Naturally Aged Skin With Vitamin A (Retinol) Reza Kafi, MD; Heh Shin R. Kwak, MD; Wendy E. Schumacher, BS; Soyun Cho, MD, PhD; Valerie N. Hanft, MD; Ted A. Hamilton, MS; Anya L. King, MS; Jacqueline D. Neal, BSE; James Varani, PhD; Gary J. Fisher, PhD; John J. Voorhees, MD, FRCP; Sewon Kang, MD Objective: To evaluate the effectiveness of topical reti- there were significant differences between retinol- nol (vitamin A) in improving the clinical signs of natu- treated and vehicle-treated skin for changes in fine wrin- rally aged skin. kling scores (−1.64 [95% CI, −2.06 to −1.22] vs −0.08 [95% CI, −0.17 to 0.01]; PϽ.001). As measured in a sub- Design: Randomized, double-blind, vehicle-controlled, left group, retinol treatment significantly increased gly- and right arm comparison study. cosaminoglycan expression (P=.02 [n=6]) and procol- lagen I immunostaining (P=.049 [n=4]) compared with Setting: Academic referral center. vehicle. Patients: The study population comprised 36 elderly Conclusions: Topical retinol improves fine wrinkles as- subjects (mean age, 87 years), residing in 2 senior citi- sociated with natural aging. Significant induction of gly- zen facilities. cosaminoglycan, which is known to retain substantial wa- ter, and increased collagen production are most likely Intervention: Topical 0.4% retinol lotion or its ve- responsible for wrinkle effacement. With greater skin ma- hicle was applied at each visit by study personnel to either trix synthesis, retinol-treated aged skin is more likely to the right or the left arm, up to 3 times a week for 24 weeks. withstand skin injury and ulcer formation along with im- proved appearance. Main Outcome Measures: Clinical assessment using a semiquantitative scale (0, none; 9, most severe) and bio- chemical measurements from skin biopsy specimens ob- Trial Registration: clinicaltrials.gov Identifier: tained from treated areas. NCT00272610 Results: After 24 weeks, an intent-to-treat analysis using the last-observation-carried-forward method revealed that Arch Dermatol. 2007;143:606-612 RINKLES AND BROWN preciated by inspecting the upper inner spots that repre- arm. Clinically evident atrophy of aged sent aged features skin correlates histologically with thin- are accentuated in ner epidermis and dermis, with reduced the habitually sun- numbers of keratinocytes and fibro- Wexposed face and the back of the hands. blasts, respectively.7,8 Reduced dermal In this premature skin aging (ie, photo- thickness is a natural consequence of docu- aging), matrix degradation triggered by so- mented reduction in procollagen synthe- lar radiation is critical in causing the 1,2 sis and constitutively elevated matrix me- wrinkled phenotype, and topical use of talloproteinases in naturally aged human retinoids can offer clinical improve- skin.7 In addition to these quantitative ment.3,4 Human skin not exposed to the Author Affiliations: changes, there is a qualitative fragmenta- Department of Dermatology, tion of dermal collagen fibers.9 These se- University of Michigan Medical CME course available at nescent changes partly explain the nota- School, Ann Arbor. Drs Kafi www.archdermatol.com bly poor wound healing and propensity for and Kwak are now with the chronic skin ulcerations seen in the el- Department of Dermatology, sun also ages but less dramatically. In in- derly population. Such fragile skin is be- Stanford Medical School, Palo Alto, Calif, and Dr Cho is trinsic, natural, or chronologic aging, skin coming a major public health issue as the now with the Department of loses its youthful appearance by becom- population grows older. Safe and effec- Dermatology, Seoul National ing thinner, laxer, and more finely tive therapies to reverse the atrophy of University, Seoul, South Korea. wrinkled.5,6 These changes are readily ap- natural skin aging do not exist currently. (REPRINTED) ARCH DERMATOL/ VOL 143, MAY 2007 WWW.ARCHDERMATOL.COM 606 ©2007 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/26/2021 This reflects our limited understanding of the natural was applied to one arm and its vehicle lotion was applied to skin aging process, as well as significant logistical chal- the contralateral arm). Assignment of treatment was made lenges in conducting clinical studies in the geriatric through a computer-generated randomization code. Approxi- population. mately 2 mL each of retinol and vehicle lotion were drawn via Among the clinical features of photoaging, wrinkles have syringe and applied to the arm at each treatment session. These unoccluded topical retinol applications were performed up to been a focus of extensive studies over the past decade. Com- 3 times per week (Monday, Wednesday, and Friday) for 24 pared with sun-protected skin, such as the buttock, pho- weeks. The treated areas were not subsequently covered with 10 toaged skin has less procollagen formation. Well- clothing. Unblinded study personnel not involved in the eval- established treatments for photoaging, such as carbon uation of study subjects traveled to the 2 residential sites 3 dioxide laser resurfacing11 or topical retinoic acid ,12,13 stimu- times a week for 24 weeks to administer treatments in mid- late procollagen synthesis and increase the mature colla- afternoons. For subjects who experienced skin irritation or ex- gen band in the high dermis (papillary dermis).14 This in- cessive dryness, treatments were discontinued for 1 or more crease in dermal collagen is associated with wrinkle treatment sessions until symptoms decreased. Subjects with un- effacement. Because accelerated skin aging due to exces- resolved irritation after 2 weeks without treatment were ter- sive sun exposure has marked collagen deficiency and ef- minated from the study. fective treatments for photoaging promote procollagen syn- thesis, we hypothesized that similar therapies might also RETINOL FORMULATION improve the collagen deficiency found in intrinsic aging. AND BIOACTIVITY For intrinsically aged skin, however, use of ablative lasers such as carbon dioxide is not feasible because it induces Retinol was formulated in the laboratory of 1 of the investiga- significant wounding that takes several weeks to heal. Topi- tors (G.J.F.) by combining a 41% retinol solution in 55% polysorbate 20 in sufficient proportions with fragrance-free cal retinoic acid and tazarotene, both approved for the treat- Norwegian Formula Neutrogena Body Moisturizer (Ortho- ment of photoaging, are not suitable for use in geriatric Neutrogena Co, Los Angeles, Calif) to yield a 0.4% retinol lo- populations either because they consistently induce skin tion. The vehicle was similarly prepared with 55% polysor- irritation at application sites.4,12,15 bate 20 solution in Norwegian Formula Neutrogena Body All-trans-retinol is a precursor to retinoic acid. When Moisturizer. There were no discernable differences in color, odor, applied to human skin, it penetrates and is sequentially or consistency between the active lotion with retinol and the oxidized to retinoic acid, causing retinoic acid–like ef- placebo lotion control. A stability study in our laboratory using fects.16 However, compared with retinoic acid, the abil- high-performance liquid chromatography demonstrated that ity of retinol to induce skin irritation is notably less, at more than 90% of 0.4% retinol remained in the moisturizer 3 least according to a 4-day patch test (an occlusive treat- months after preparation. Therefore, 0.4% retinol lotion and 16,17 vehicle were formulated every 2 months to ensure that ad- ment). Thus, retinol has the potential to deliver reti- equate amounts of the active ingredient were present through- noic acid–like effects to human skin with improved tol- out the study. Both 0.4% retinol lotion and its vehicle were placed erability. We report herein a geriatric clinical study in dark glass containers covered with foil to eliminate trans- (patients 80 years or older only) assessing the effective- mission of UV radiation and stored at 4°C. ness of topical retinol in effacing fine wrinkling as a clini- A separate bioactivity study using this 0.4% retinol formu- cal end point for reversal of skin atrophy. This clinical lation was also conducted on 5 healthy nongeriatric volun- observation is complemented by molecular measure- teers. This protocol was also approved by our institutional re- ments of procollagen and glycosaminoglycan (GAG). view board, and written informed consent was obtained from the subjects prior to enrollment. The CRABPII gene contains a retinoic acid–responsive element.18 Its messenger RNA (mRNA) METHODS is induced by topical application of retinoids dose- dependently, thus serving as a reliable reporter of retinoid ac- SUBJECTS tion.16,19 Retinol lotion, its vehicle, 0.1% retinoic acid in ethanol- propylene glycol (positive control), and ethanol-propylene glycol The protocol was approved by the University of Michigan Medi- (negative control) were applied on buttock skin, and a biopsy cal School institutional review board, and written informed con- from each treatment site was obtained after 24 hours. sent was obtained from all subjects prior to enrollment. Eli- CRABPII mRNA levels were measured with quantitative real- gible patients were 80 years or older, in relatively good health, time reverse transcriptase–polymerase chain reaction (RT- and without active skin diseases involving the upper extremi- PCR), as previously described.20 ties. Forty-four subjects were screened for the study from March 2001 until December 2002. The last visit by a subject oc- CLINICAL EVALUATIONS curred in August 2002. A total of 36 subjects with a minimum age of 80 years from 2 senior citizen centers were enrolled in Evaluations were performed by 2 blinded dermatologists (V.N.H. the study, and 23 subjects completed the entire study. The mean and S.K.) at baseline and then at weeks 2, 4, 8, 16, and 24. Clini- age was 87 years (range, 80-96 years), and the male-female ra- cal evaluations of the upper inner arms were based on (1) tac- tio was 1:2.5.