- Email: [email protected]
Sustained improvement with prolonged topical tretinoin (retinoic acid) for photoaged skin
Clinical and laboratory studies Sustained improvement with prolonged topical tretinoin (retinoic acid) for photoaged skin Charles N. Ellis, MD,a Jonathan S. Weiss, MD,a,* Ted A. Hamilton, MS,a John T. Headington, MD,a,b Alvin S. Zelickson, MD,c and John 1. Voorhees, MDa Ann Arbor, Michigan, and Minneapolis, Minnesota We performed a 22-month trial of topical tretinoin (retinoic acid) in the treatment of photoaging. Thirty patients participated in a 4-month, randomized, blinded, vehicle-controlled studythat has beenreported previously; 21 patients continued tretinoin therapy on an openlabelbasis, participating in the studyfor a totalof 10months, and 16patients continued for 22 months. During the open-label study, the statistically significant improvement that had occurred infine and coarse wrinkling andskin texture duringouroriginal study wassustained, despite reductions in dose or frequency of application of tretinoin. The number of discrete lentigines decreased by 71 % compared withthenumber before therapy.Histologic findings included a statistically significant thickening ofthe epidermis. Side effects were limited to a cutaneous retinoid reaction that diminished astherapyproceeded. (J AMACAD DERMATOL 1990;23:629-37.) WeI have demonstrated in a 4-month trial that topical tretinoin (all-trans-retinoic acid, Retin-A) improves photoaged skin. Histologic' and ultrastructura12, 3 changes seen in forearm skin treated with tretinoin but not in skin treated with vehicle cream included compaction of stratum corneum, increased granular layer and epidermal thickness, increased numbers of mitoses in keratinocytes, presence of glycosaminoglycan-like substance in the compacted stratum corneum, increased numbers of anchoring fibrils at the dermoepidermaljunction, and improvement of epidermal dysplastic changes. Herein we report the results of an open-label trial, extending tretinoin therapy for up to 22 months, in patients who had completed our original 4-month study. 1
MATERIAL AND METHODS
Patients The 30 patients who completed our original doubleblind study were asked to continue in a 6-month open study; 21 agreed. After 6 months of therapy had been completed, the patients were asked to continue in the study for another year, and 16 agreed. Of the nine patients who leftthestudyafter the initial 4months, six cited either the inconvenience of the protocol or that they did notwantfurtherbiopsies andthreecited intermittent skin irritation. Allfive wholeftafter 10months citedinconvenience or biopsies as the reason. No patient gavelack of efficacy asa reasonfor leaving. Allsegments ofthe study were approved by The University of Michigan Medical CenterInstitutional Review Board, andinformed consent was obtained from all patients after the nature of the study and procedures had been explained.
Treatment From the Dermatopharmacology Unit, Department ofDermatology," and Department of Pathology," University of Michigan Medical
Center, Ann Arbor, and the Department of Dermatology, University Minnesota Medical School, Minneapolis," Supported by a grant from R. W. Johnson Pharmaceutical Research Institute atOrtho Pharmaceutical Corp., Raritan, N.J., and by the Babcock Dermatologic Endowment, Ann Arbor, Mich. Presented in part atthe Forty-sixth Annual Meeting of the American Academy ofDermatology, Washington, D.C., Dec. 3-8, 1988. Accepted for publication Jan. 5, 1990. Reprint requests: John J.Voorhees, MD, Department of Dermatology, University ofMichigan Medical Center, Room 1910 Taubman Center, 1500 East Medical Center Dr., Ann Arbor, MI 48109-0314. "Dr, Weiss is now with Emory University School ofMedicine, Atlanta. of
16/1/19369
Asin ouroriginal study, treatmentsites consisted ofthe faceand thedorsal aspectofthe forearms and hands. Patients applied tretinoincream (Retin-A, Ortho Pharmaceutical Corp., Raritan, N.J.) daily to these areas. Patients had applied tretinoin cream to one forearm and vehicle to the other in our original 4-month study. Therefore in this extended trial allpatients had oneforearm to which theyapplied tretinoin cream (T) for a total of 10months (lOT) and 22months (22T) and one forearm to which theyapplied vehicle cream(V)for4 months (4V), followed by tretinoin cream in an open-label fashion for 6 months (4V + 6T) and 18months (4V + 18T). In our original study,patients wererandomly assigned to applytretinoin or vehicle to the facefor 4 months (4T
629
Journal of the American Academy of Dermatology
630 Ellis et al.
Table 1. Study design, abbreviations used, and numbers of patients completing each study phase Originalstudy! (4 mol Vehicle
Random assignment; parallel groups Group 1: Face 4V (n = 15) Group 2: Face
I
Open study I (6 mol
Open study 2 (12 mol
0.1'Yo Tretinoin
0.05 % or 0.1% Tretinoin
0.05 % or 0.1% Tretinoin
4T (n = 15)
4V+6T (n = 12) lOT (n = 9)
4V + 18T (n = 8) 22T (n = 8)
4V+6T (n = 21) lOT (n = 21)
4V + 18T (n = 16) 22T (n = 16)
All patients; bilateral comparison One forearm Other forearm
4V (n = 30) 4T (n = 30)
For explanation of abbreviations see text ("Material and Methods: Treatment").
or 4V). Those patients who received tretinoin during the originalstudy applied tretinoin cream to the face for a total of 10 months (lOT) and 22 months (22T). Those patients who applied vehicle cream to the face during the double-blind study received tretinoin to the face for a total of 6 months (4V + 6T) and 18 months (4V + 18T) (Table I). All patients used tretinoin 0.1 % cream in our original study. Depending on frequency and tolerance by patients of previous side effects, we assigned nine patients in the initial open-label phase lasting 6 months to continue usingtretinoin 0.1%cream daily, nine to 0.05%cream daily, two to 0.1% cream on the arms and 0.05% cream on the face daily; one began with 0.05% cream but increased to 0.1% cream 4 months later. During the second open-label phase lasting 12months, three patients continued with 0.1%cream daily, eight used0.1 % cream every other day, and five used 0.05% cream every other day. Application of topical agents other than tretinoin was restricted, as in our original study. Patients were supplied with mildsoap and emollient cream (Purpose, Johnson & Johnson Products, Inc., New Brunswick, N.J.). Sunscreen (Sundown-SPF 15, Johnson & Johnson) was supplied for use in advance of prolonged sun exposure. Patients were instructed to use the same brands and quantities of cosmetics as they had before and during the original study.
Clinical evaluations Patients' faces and forearms were graded for indicators of photoaging: (1) finewrinkling, (2) coarse wrinkling, (3) texture (tactile roughness), (4) telangiectasia, and for treatment effects: (1) pinkness, (2) dermal edema. The grading scale for each parameter or treatment effect ranged from 0 to 4 (0 = absent, 1 = mild, 2 = moderate, 3 =moderately severe, 4 == severe). In addition, lentigineswere counted under normal lighting conditions. All grading for all visits of every patient was carried out by
the same investigator (J. S. W.) who, throughout the study, was unaware of the individual assignments of tretinoin or vehicle made in the original4-month study, although he was aware of the results of mean data presented by us.' Evaluations were made monthly for 6 months and every 2 months thereafter. Evaluations were performed at least 14 hours after the patient applied the test cream to reduce or eliminate cosmetic improvements caused by the temporary moisturizing effect of the cream.
Skin biopsy specimens One 4 rom full-thickness punch biopsy specimen was taken from the proximal third of the dorsal aspect of each forearm before therapy (n = 28 patients), at the end of our original 4-month study (n = 28), after 10 months (n = 21), and after 22 months (n = 16). Biopsy specimens were prepared for light microscopy and interpreted in a manner identical to that in our original study.' In a similar fashion before therapy and after 4 and 10 months, 2 mm punch biopsy specimens were obtained from seven patients. These specimens were placed in a cacodylatebuffered (pH 7.2) 2.5% glutaraldehyde solution, postfixed in 1% osmium tetroxide, dehydrated in ethanol, and embedded (Spurr embedding medium). Thin sections were stained with uranyl acetate and lead citrate and examined with an electron microscope (model EMU4, RCA, Camden, N.J.). All specimens were taken within 1 to 2 em of each other; care was taken to avoid scar tissue, keratoses, and lentigines. Throughout the study, specimens were provided to the microscopists (1. T. H. and A. S. Z.) in a coded fashion.
Statistical method Data are reported as means ± 1 standard error of the mean; all p values are two-sided. The analyses were performed with the use of the Michigan Interactive Data Analysis System (MIDAS), a statistical software pack-
Volume 23 Number 4, Part 1 October 1990
Prolonged tretinoin for photoaging 631 OPEN
DOUBLE-BLIND
w
o
w2.5
ciS
c:s 2.0
DOUBLE·BLIND OPEN 1.0·,r--------,--------,
if~
4V+ 6T
~lI)
~ ~ 1.5
**
~ ~ 1.0 ~
lI)
4V+
1ST
10T
*
4V+
22T
1ST
0.5
22T
Ii:
A
N;;8
BL
4 MOS.
22 MOS.
4 MOS.
B
22 MOS.
1.5
~ w 1.2
if~ en g 0.9 ffi~ ~ 4V+
1ST 22T
s 0.6
zGj a:::
CI)
4V+ 18T 22T
0.3
N=8 N;;8
BL
N;;8 N=8
BL
D
Fig. 1. Clinical parameters of the face over time. Large, open bars indicate mean; smaller bars indicate standard error. Severity score scales vary to aid in graphic representation. Values for p in double-blind phase refer to comparisons of changes from baseline between V (vehicle) and T (tretinoin) groups. Values for p in open phase refer to comparisons to baseline. For explanation of V and T see Table I and text. BL. Baseline (pretherapy); N, number of patients evaluated in each treatment regimen at each time point; MOS, months of study duration (first 4 months were performed in double-blind design! whereas the remaining 18 months were open-label). 0.05
r,
age developed by the Statistical Research Laboratory at The University of Michigan. The time points for presentation of the data were chosen to correspond with the completion of the various phases of the protocol. Original study (pretberapy to 4 montbs),These methods are described in our original article.' Open-label phases (4 to 22 months). At 10 and 22 months, data for each treatment regimen were compared with the respective pretherapy values and analyzed with the sign test (for efficacy data and discrete histologic parameters) or the paired Student t test (for continuous histologic measurements). The Wilcoxon signed-rank test was used to compare 4T with lOT data. The statistics are presented for descriptive purposes; therefore no adjustment for the number of comparisons was made. Statistical comparisons at each time-point include only those patients who remained in the study and exclude data ofpatients who withdrew before then.
Representative nature of study patients To ensure that the patients who completed the study were representative of the original cohort of 30 patients, a comparison was made of the overall response after 4 months oftretinoin therapy between the 16 patients who
went on to complete the study and the 14 who left before completion. As in our original study, overall response was determined on a scale of 1 to 5 (1 = much improved, 2 = improved, 3 = slightly improved, 4 = no change, 5 = worse). The results showed no detectable differences in improvement (p = 1.0, Wilcoxon rank-sum test) for both groups after 4T. Thus there was no evidence for the introduction of a bias in our open-label trial related to the patients' decision to continue in the study as a result of their clinical improvement or lack thereof.
RESULTS
Clinical results During the open-label phases, the mean scores for fine and coarse wrinkling and texture indicate that the improvement that occurred in our original, 4-month study was sustained (Figs. 1,2, and 3). Fine wrinkling and surface texture continued to show the most consistent improvement in the mean scores of both arms and face compared with those before therapy. As demonstrated by the changes in means from 4V to 4V + 6T and from 4T to lOT (Figs. 1 and 2), most of the alterations in the clinical indica-
632
Journal of the American Academy of Dermatology
Ellis et al. DOUBLE·BlIND
OPEN
DOUBLE·BLlND
OPEN
lJ)
~w
(I)~
~ ~3.0 ~ t7) 2.4
1~1.5
4V+ 6T 10T
~ ~1.8 -a:
4V+ 18T 22T
a:w
~
[j 1.2
~
lJ)
1.8
~
1.2
~~0.9
4V+ 6T 10T
~~0.6
0.6
N=16
**** **** **** **** ....... N==21
en 0.3
[;
4V+ 18T 22T
""'T"""........
0.0 LL~:::-JLL~~llr:::E::r:::E:::L.J~~:.lJ
A
10 MOS.
B
22 MOS.
lJ)
:::E
~w •. II: 2.0
en w 2.4 ~ ~2.0
~§1.6
i
~1.2
!i
lJ)
.. en 1.6 ~~ w CE 1.2
~wO ~ £ij .8
8
****
Zw
0.4 0.0.L-L---=-"_1.-J....---L
~
ai 0.8
c,
en 0.4
.u.L..---L_J......I...---L_J-J
o
C
V
T
N=30
0.0 l.Gt:::r::;tJ-...r:::;ti-llL-=t~U..:J~1J BL
Fig. 2. Clinical parameters of the arms over time. For explanationof symbols, see Fig. 1. N. Number of patients evaluated at each time point; one arm received each treatment regimen indicated. Mean severityvaluesare identical for texturein the openphases becausemost patients had scores of O.
Table II. Number of lentigines present on the face Patient No.
.5 31 32 36 38 39 Total
4 4 3 7 2 I 21
After 6 to 10 rno tretinoin therapy*
After 18 to 22 rno
o o
o o
2 4 1
2 4
a
"7
tretinoin therapy*
o
o
6
*p = 0.03 compared with pretherapy; sign test. Only patients with discrete, counted lentigines are included.
tors occurred during the first 6 to 10 months of tretinoin therapy. There was greater pinkness of the skin compared with the pretherapy skin color at all evaluations after tretinoin therapy had begun (Figs. I and 2). In all patients with discrete, countable lentigines, the number of lentigines was reduced after 6 months or more of tretinoin treatment (Table II); lightening of color occurred in lentigines that did not disappear. Tretinoin had no positive or negative effect on
telangiectasia and it did not induce clinically detectable dermal edema. To determine whether extending therapy beyond the 4 months of our original study is of clinical benefit despite the reduction in tretinoin concentration used in the open phase, we compared the scores for the photoaging indicators at 4T with those at lOT. On the arms after 10 months of tretinoin therapy, mean scores for fine wrinkling, texture, and coarse wrinkling were lower than the 4-month values (p == 0.0002,0.001, and 0.07, respectively). The improvement that was noted after lOT was maintained at 22T (i.e., there was no statistically significant difference in the scores of photoaging between lOT and 22T). The parallel design provided too few comparisons to perform a similar analysis for data from the face. Patients were not assigned randomly to the two concentrations of tretinoin (0.1 % and 0.05%) used in the open phases; therefore the effect ofconcentration cannot be definitively assessed and an optimal treatment regimen cannot be determined from our data. Nevertheless, for descriptive purposes, we have examined the mean scores for the nine patients who
Volume 23 Number 4, Part 1 October 1990
Prolonged tretinoin for photoaging
Fig. 3. A, Before tretinoin therapy (after 4V). B, After 6 months of tretinoin treatment. C, After 18 months of tretinoin therapy. All photographs were taken with a Nikon F3 35 mm camera with a Nikon 105 mm micro-Nikkor lens bracketed at F 11 to F16 using Kodachrome 25 ASA professional film with side lighting, which was positioned in standard fashion by measurement to within 1 em. Blue background was changed to black after the first picture. Photographs were obtained only to document clinical changes and were not used for data collection or analysis; all data were obtained from direct observations of patients.
633
634
Journal of the American Academy of
Ellis et al.
Dermatology
Fig. 4. Representative photomicrographs of skin from forearms. A, Before therapy, demonstrating a woven stratum corneum with minimal cytologic atypia in epidermis normal in thickness for the forearm, and moderate elastosis in papillary dermis. B, After 4 months of tretinoin therapy, showing compaction of the stratum corneum, thicker epidermis without cytologicatypia, and slight elastosisin papillary dermis. C, After 10 months of tretinoin therapy, demonstrating findings similar to 4-month specimen, with thickness of the epidermis greater than that before therapy but lessthan at 4 months, and slight dermal elastosis. D, After 22 months, similar to the IG-monthspecimenbut with moderate dermal elastosis. Variability in dermal elastosis is due to individualvariation and not the result of therapy; there were no consistent changes in the dermis that could be observed by light microscopy. (A, B, C, and D, Hematoxylin-eosin stain; X50.)
received tretinoin 0.05% daily and the 11 patients who received tretinoin 0.1 % daily in the initial open phase lasting 6 months. The differences in the mean scores for the photoaging parameters between the two groups were clinically insignificant (differences of 0.02 to 0.30 units) at both 4V + 6T and lOT. There was no difference in adverse effects between the two groups.
i\dverse effects Episodic peeling, dryness, and erythema were the only side effects detected during the 22 months of this study; these were relieved by reducing the frequency of tretinoin application or by avoiding application of the medication to the area of reaction for a few days. Only one patient used a topical cortico-
steroid once for 2 days during the open-label phases. The side effects were generally limited to the antecubital fossa and the neck; biopsy specimens were not obtained from areas exhibiting side effects.
Histologic results Before tretinoin therapy, the stratum corneum exhibited a woven pattern (Fig. 4) in 94% of forearm biopsy specimens. After 4 months of tretinoin treatment, 89% of the samples of stratum corneum exhibited compaction, with a homogeneous appearance or a combination of woven and compacted corneocytes; only 11% showed a purely woven pattern. Similarly, after 6 to 10 months of tretinoin therapy, 71 % of all specimens demonstrated compaction of the stratum corneum. However, after 18 to 22
Volume 23 Number 4, Part I October 1990
months of tretinoin therapy, the stratum corneum reverted to the pretherapy condition in many patients; 69% of specimens demonstrated a wovenpattern. The number of cells in the granular layer doubled, on average, from pretherapy to the end of the study (Fig. 5). The mean epidermal thickness increased by more than one third over the pretherapy value at all time points during tretinoin therapy (Fig. 5). The number of mitotic figures in seven adjacent highpower fields peaked early during tretinoin therapy and decreased to near pretherapy levels by the end of the study. The number of specimens with two or more mitoses were as follows: zero at pretherapy; zero at 4V versus nine at 4T (p = 0.01); three at 4V + 6T and three at lOT (p < 0.05 for each compared with pretherapy); and one at both 4V + 18T and 22T (p = no significance). During tretinoin therapy, there was an increase in an alcian blue-positive substance in the epidermis and stratum corneum, although this material became less apparent after prolonged treatment. No qualitative or quantitative changes in dermal collagen were detected .
Ultrastructural results In the pretherapy specimens the stratum corneum was thick (approximately 40 cells from the granular layer to the free surface). Intracellular structural proteins of the keratinocytes were dense and irregular. Melanin was also readily apparent throughout the stratum corneum and in the epidermis, especially in the lower portions capping the nuclei of keratinocytes. At the dermoepidermal junction, anchoring fibrils were sparse. Collagen in the papillary dermis had a smudged appearance and was aligned haphazardly; nearby fibroblasts contained enlarged mitochondria and distorted endoplasmic reticulum. The samples obtained after 4 months- and 10 months of therapy were similar. In the stratum corneum, there were approximately 25% fewer cell layers, and the cells were thinner and more electrondense. A fine granular material, similar to that found in the epidermis after oral retinoid therapy and thought to be mucoid ," was seen between cells. Structural proteins in keratinocytes were thinner and more orderly. Melanin appeared less frequently throughout the keratinocyte layers and was essentially absent from the stratum corneum. Anchoring fibrils were more numerous (Fig. 6).3 Collagen with a normal-appearing structure and orientation was present in the papillary dermis and nearby fibro-
Prolonged tretinoin for photoaging 635 DOUBLE· BLIND
V
T
4V
4T
N=15 N= 15
N=12 N=9
N=8 N=8
BL
4 MOS,
10 MOS.
22 MOS.
OPEN
100·
(J)
f3
********
~ _80'
u(/')
i: ~ 60 a: u
~~
riiiEh4_
40 '
a:w o 20 -
a:: w
4V+ 1ST 22T
4V+ 6T lOT
N=15 N=15
DOUBLE·BLlND
I-I
OPEN
v
T
4V
4T
4V+ 6T 10T
4V-'1ST 22T
N=15 N=15
N=15 N=15
N=12 N=9
N=8
BL
4 MOS.
10 MOS.
22 MOS.
N=8
Fig. 5. Histologic parameters in biopsy specimens from forearms over time. For explanation of symbols see Fig. 1. For explanation of N . see Fig. 2.
blasts had normal-appearing mitochondria and endoplasmic reticulum. DISCUSSION
Our results indicate that clinical improvement was sustained when topical tretinoin therapy was applied for up to 22 months, even when the dosage or frequency of application of tretinoin was reduced. Although patients treated with the vehicle cream alone for 4 months in our original study had no discernible improvement, I therapeutic benefit occurred after they began tretinoin applications (Figs . 1 and 2). In addition, with prolonged tretinoin treatment, 71% of discrete lentigines (so-called liver or age spots) disappeared (Table II). Our results provide further support for drug-induced improvement of photoaged skin, including wrinkles, and are consistent with other clinical studies.>? We acknowledge three sources of potential bias in this study, arising from (1) the retinoid react ion experienced by some patients, (2) the unblinded nature of the open-label segment, and (3) patient attrition. The first occurred in the double-blind phase and has been discussed in detail. 1 We decided that it would not be feasible to prolong the double-blind and vehicle-controlled design of our original study. Therefore, as with all open trials, our results may be biased, presumably yield-
636 Ellis et al.
Journal of the American Academy of Dermatology
Fig. 6. Representative electron micrographs of skin from forearms. A, Before therapy; few anchoring fibrils (AF) are seen along dermoepidermal junction (BL, basal lamina). B, After 4 months of topical tretinoin therapy; anchoring fibrils (arrows) are more easily seen compared with those before therapy; collagen with normal appearance and orientation runs along bottom of figure. C, After 10 months of therapy, findings are similar to those after 4 months; anchoring fibrils are easily seen (arrows). (A, B, and C, X46,OOO.)
ing an overly favorable view of tretinoin activity. However, many of our patients had severe enough photodamage that the effects of extended tretinoin therapy could be documented by photography (Fig. 3) and show that our results cannot be due to evaluator bias alone. In addition, the microscopic and ultrastructural findings from coded specimens confirmed that retinoid-induced effects occurred in the skin. Such effects, which occurred in our study and also occur with oral retinoid therapy, include proliferation of epidermal cells," thickened granular cell layer.? presence of a mucoid substance in the epidermis's 10-12 that may be hyaluronate synthesized by keratinocytes, 13 and normalization of basal layer tonofilaments, 14, IS With regard to the introduction of a bias by patient attrition, we were concerned that only the responsivepatients may have remained in the study for its full duration whereas those with more modest results left, thereby imparting a positive bias to our re-
sults, However, a comparison ofthe overall response of the 16 patients who remained versus the 14 who departed early revealed that both groups responded equally well to tretinoin. As indicated in Figs. 1 and 2 and Table II, most clinical changes induced by tretinoin therapy were achieved by the sixth to tenth month of treatment. Certain aspects of this study may have influenced the time at which most of the benefit was recognized, including the discrete ordinal scales we used, and the reduction in both tretinoin concentration and frequency of application that most of our patients employed. Although the study was not designed to determine a precise maintenance regimen, our data indicate that the lower 0.05% concentration or alternate-day applications of tretinoin are effective in sustaining the improvements in photoaged skin generated by daily application of tretinoin 0.1 % cream. The increased pinkness of the skin that develops
Volume 23 Number 4, Part I October 1990
during tretinoin application (Figs. I and 2) generally enhances appearance. Pinkness of the skin is caused by oral retinoid therapy as wel1 16 and thus cannot be due solely to a putative contact irritation induced by tretinoin. Indeed, evidence of inflammation was lacking in biopsy specimens even of pink skin. The only problems encountered by our patients were dryness of the skin and a so-called dermatitis characterized by erythema and flaking of the stratum corneum. These reactions occur in response to oral or topical retinoid therapy'< 17 and do not represent an allergic contact or irritant dermatitis. 18 As in our original work, we carefully avoided areas of retinoid reaction when patients' skin was evaluated or subjected to biopsy. As therapy proceeded in the open-label phases, the incidence and degree of the reaction declined and in most patients disappeared; however, clinical benefit was maintained. The discordant time courses suggest that desirable retinoid activity, not side effects,'? yields improvement of photoaged skin. The reduction in the cutaneous side effects that occur with continued use of tretinoin may be related to changes in the stratum corneum. Although the character of this layer was altered early in therapy, later it reverted toward normal in most patients. The cause of this tachyphylactic response to tretinoin in the stratum corneum, despite the increase in epidermal thickness that remained constant throughout the study, is unknown. However, the return of the stratum corneum to a woven pattern may result in a more physiologic skin barrier; if so, diminished peeling and dryness and normal corneal resistance to ultraviolet irradiation and transepidermal water loss could result. As yet we have no formally gathered data regarding the prolongation of the effects of tretinoin after therapy has been stopped. However, our limited clinical experience suggests that improvement persists for at least 2 months after therapy, followed by a gradual, partial regression. These findings do not support the concept that edema contributes to the improved appearance of our patients' skin 19 because edema would be expected to subside within a few days after treatment is stopped. Our patients' skin had undergone both chronologie aging and photodamage before therapy. Because these conditions cannot be easily separated, we do not yet know whether tretinoin therapy improves both of them. Nevertheless, our histologic and ultrastructural findings indicate that tretinoin therapy causes more than esthetic improvement; it also induces anatomic changes in the epidermis and
Prolonged tretinoin for photoaging 637 papillary dermis, in all likelihood without regard to whether the skin has been changed by time or sun. REFERENCES 1. Weiss JS, Ellis C~, Headington JT, et al. Topical tretinoin improvesphotoagcd skin. A double-blind vehicle-controlled study. JAMA 1988;259:527-32, 2. Zelickson AS, Mottaz JH, Weiss JS, et al. Topical tretinoin in photoaging: an ultrastructural study. J Cutan Aging Cosmet DermatoI1989;1:41-7. 3. Woodley DT, Zelickson AS, Briggaman RA, et al. Treatment of photoaged skin with topical tretinoin increases epidermal-dermal anchoring fibrils: a preliminary report. JAMA (In press.) 4. Ellis CN, Gold RC, Grekin RC, et al. Etretinate therapy stimulates deposition ofmucus-like material in epidermis of patients with psoriasis. J AM ACAD DERMATOL 1982; 6:699-704. . 5. Cordero A Jr. La vitamina A acida en la piel senil. Actualizaciones Terapeuticas Dermatol6gicas 1983;6:49-54. 6. Kligman AM, Grove GL, Hirose R, et al. Topical tretinoin for photoaged skin. J AM ACAD DERMATOL 1986;15:83659. 7. Leyden 11, Grove GL, Grove MJ, et al. Treatment of photodamaged facial skin with topical tretinoin. J AM ACAD DERMATOL 1989;21:638-44. 8. Gillenberg A, Immel C, Orfanos CEo Retinoid-EiflufJ auf die Zellkinetik gesunder menschlicher Epidermis. Arch Dermatol Res 1980;269:331-5. 9. Jablonska S, Wolska H, Dabrowski J, et al. Aromatic retinoids in psoriasis: clinical, histological, histochemical, electron microscopical and immunological investigations. In: Orfanos CE, Braun-Falco 0, Farber EM, et aI., eds. Retinoids: advances in basic research and therapy. Berlin: Springer-Verlag, 1981:165-73. 10. Orfanos CE, Runne U. Tissue changes in psoriatic plaques after oral administration of retinoid. Dermatologica 1978; 157(suppll):19-25. 11. Kanerva LO, Johansson E, Niemi K-M, et al. Epiderrnodysplasia verruciformis. Clinical and light- and electronmicroscopic observations during etretinate therapy. Arch Dermatol Res 1985;278:153-60. 12. Elias PM. Epidermal effects of retinoids: supramolecular observations and clinical implications. J AM ACAD DERMATOL 1986;15:797-809. 13. Tammi R, Ripellino JA, Margolis RU, eta!. Hyaluronate accumulation in human epidermis treated with tretinoin in skin organ culture. J Invest Dermatol 1989;92:326-32. 14. Lauharanta J, Niemi K-M, Lassus A. Treatment of Darier's disease with an oral aromatic retinoid (Ro 109359): a clinical and light and electron microscopic study. Arch Derm Venereol (Stockh) 1981;61:535-42. 15. Schultz-Ehrenburg U, Orfanos CEoLight and electron microscopic changes of human epidermis under oral retinoid treatment. In: Orfanos CE, Braun-Falco 0, Farber EM, et al., eds. Retinoids: advances in basic research and therapy. Berlin: Springer-Verlag, 1981:85-92. 16. Ellis CN, Voorhees JJ. Etretinate therapy. J AM ACAD DERMATOL 1987;16:267-91. 17. Silverman AK, Ellis CN, Voorhees JJ. Hypervitaminosis A syndrome: a paradigm of retinoid side effects. J AM ACAD DERMATOL 1987;16:1027-39. 18. Esmann J, Griffiths CEM, Talwar HS, et al. Biochemical and immunological characterization of the "retinoid reaction" in normal human skin [Abstract]. Clin Res 1989; 37:349A. 19. Ellis CN, Weiss JS, Hamilton TA, et al. Topical retinoic acid for photoaged skin: in reply. JAMA 1988;259:3271-4.
MATERIAL AND METHODS
Patients The 30 patients who completed our original doubleblind study were asked to continue in a 6-month open study; 21 agreed. After 6 months of therapy had been completed, the patients were asked to continue in the study for another year, and 16 agreed. Of the nine patients who leftthestudyafter the initial 4months, six cited either the inconvenience of the protocol or that they did notwantfurtherbiopsies andthreecited intermittent skin irritation. Allfive wholeftafter 10months citedinconvenience or biopsies as the reason. No patient gavelack of efficacy asa reasonfor leaving. Allsegments ofthe study were approved by The University of Michigan Medical CenterInstitutional Review Board, andinformed consent was obtained from all patients after the nature of the study and procedures had been explained.
Treatment From the Dermatopharmacology Unit, Department ofDermatology," and Department of Pathology," University of Michigan Medical
Center, Ann Arbor, and the Department of Dermatology, University Minnesota Medical School, Minneapolis," Supported by a grant from R. W. Johnson Pharmaceutical Research Institute atOrtho Pharmaceutical Corp., Raritan, N.J., and by the Babcock Dermatologic Endowment, Ann Arbor, Mich. Presented in part atthe Forty-sixth Annual Meeting of the American Academy ofDermatology, Washington, D.C., Dec. 3-8, 1988. Accepted for publication Jan. 5, 1990. Reprint requests: John J.Voorhees, MD, Department of Dermatology, University ofMichigan Medical Center, Room 1910 Taubman Center, 1500 East Medical Center Dr., Ann Arbor, MI 48109-0314. "Dr, Weiss is now with Emory University School ofMedicine, Atlanta. of
16/1/19369
Asin ouroriginal study, treatmentsites consisted ofthe faceand thedorsal aspectofthe forearms and hands. Patients applied tretinoincream (Retin-A, Ortho Pharmaceutical Corp., Raritan, N.J.) daily to these areas. Patients had applied tretinoin cream to one forearm and vehicle to the other in our original 4-month study. Therefore in this extended trial allpatients had oneforearm to which theyapplied tretinoin cream (T) for a total of 10months (lOT) and 22months (22T) and one forearm to which theyapplied vehicle cream(V)for4 months (4V), followed by tretinoin cream in an open-label fashion for 6 months (4V + 6T) and 18months (4V + 18T). In our original study,patients wererandomly assigned to applytretinoin or vehicle to the facefor 4 months (4T
629
Journal of the American Academy of Dermatology
630 Ellis et al.
Table 1. Study design, abbreviations used, and numbers of patients completing each study phase Originalstudy! (4 mol Vehicle
Random assignment; parallel groups Group 1: Face 4V (n = 15) Group 2: Face
I
Open study I (6 mol
Open study 2 (12 mol
0.1'Yo Tretinoin
0.05 % or 0.1% Tretinoin
0.05 % or 0.1% Tretinoin
4T (n = 15)
4V+6T (n = 12) lOT (n = 9)
4V + 18T (n = 8) 22T (n = 8)
4V+6T (n = 21) lOT (n = 21)
4V + 18T (n = 16) 22T (n = 16)
All patients; bilateral comparison One forearm Other forearm
4V (n = 30) 4T (n = 30)
For explanation of abbreviations see text ("Material and Methods: Treatment").
or 4V). Those patients who received tretinoin during the originalstudy applied tretinoin cream to the face for a total of 10 months (lOT) and 22 months (22T). Those patients who applied vehicle cream to the face during the double-blind study received tretinoin to the face for a total of 6 months (4V + 6T) and 18 months (4V + 18T) (Table I). All patients used tretinoin 0.1 % cream in our original study. Depending on frequency and tolerance by patients of previous side effects, we assigned nine patients in the initial open-label phase lasting 6 months to continue usingtretinoin 0.1%cream daily, nine to 0.05%cream daily, two to 0.1% cream on the arms and 0.05% cream on the face daily; one began with 0.05% cream but increased to 0.1% cream 4 months later. During the second open-label phase lasting 12months, three patients continued with 0.1%cream daily, eight used0.1 % cream every other day, and five used 0.05% cream every other day. Application of topical agents other than tretinoin was restricted, as in our original study. Patients were supplied with mildsoap and emollient cream (Purpose, Johnson & Johnson Products, Inc., New Brunswick, N.J.). Sunscreen (Sundown-SPF 15, Johnson & Johnson) was supplied for use in advance of prolonged sun exposure. Patients were instructed to use the same brands and quantities of cosmetics as they had before and during the original study.
Clinical evaluations Patients' faces and forearms were graded for indicators of photoaging: (1) finewrinkling, (2) coarse wrinkling, (3) texture (tactile roughness), (4) telangiectasia, and for treatment effects: (1) pinkness, (2) dermal edema. The grading scale for each parameter or treatment effect ranged from 0 to 4 (0 = absent, 1 = mild, 2 = moderate, 3 =moderately severe, 4 == severe). In addition, lentigineswere counted under normal lighting conditions. All grading for all visits of every patient was carried out by
the same investigator (J. S. W.) who, throughout the study, was unaware of the individual assignments of tretinoin or vehicle made in the original4-month study, although he was aware of the results of mean data presented by us.' Evaluations were made monthly for 6 months and every 2 months thereafter. Evaluations were performed at least 14 hours after the patient applied the test cream to reduce or eliminate cosmetic improvements caused by the temporary moisturizing effect of the cream.
Skin biopsy specimens One 4 rom full-thickness punch biopsy specimen was taken from the proximal third of the dorsal aspect of each forearm before therapy (n = 28 patients), at the end of our original 4-month study (n = 28), after 10 months (n = 21), and after 22 months (n = 16). Biopsy specimens were prepared for light microscopy and interpreted in a manner identical to that in our original study.' In a similar fashion before therapy and after 4 and 10 months, 2 mm punch biopsy specimens were obtained from seven patients. These specimens were placed in a cacodylatebuffered (pH 7.2) 2.5% glutaraldehyde solution, postfixed in 1% osmium tetroxide, dehydrated in ethanol, and embedded (Spurr embedding medium). Thin sections were stained with uranyl acetate and lead citrate and examined with an electron microscope (model EMU4, RCA, Camden, N.J.). All specimens were taken within 1 to 2 em of each other; care was taken to avoid scar tissue, keratoses, and lentigines. Throughout the study, specimens were provided to the microscopists (1. T. H. and A. S. Z.) in a coded fashion.
Statistical method Data are reported as means ± 1 standard error of the mean; all p values are two-sided. The analyses were performed with the use of the Michigan Interactive Data Analysis System (MIDAS), a statistical software pack-
Volume 23 Number 4, Part 1 October 1990
Prolonged tretinoin for photoaging 631 OPEN
DOUBLE-BLIND
w
o
w2.5
ciS
c:s 2.0
DOUBLE·BLIND OPEN 1.0·,r--------,--------,
if~
4V+ 6T
~lI)
~ ~ 1.5
**
~ ~ 1.0 ~
lI)
4V+
1ST
10T
*
4V+
22T
1ST
0.5
22T
Ii:
A
N;;8
BL
4 MOS.
22 MOS.
4 MOS.
B
22 MOS.
1.5
~ w 1.2
if~ en g 0.9 ffi~ ~ 4V+
1ST 22T
s 0.6
zGj a:::
CI)
4V+ 18T 22T
0.3
N=8 N;;8
BL
N;;8 N=8
BL
D
Fig. 1. Clinical parameters of the face over time. Large, open bars indicate mean; smaller bars indicate standard error. Severity score scales vary to aid in graphic representation. Values for p in double-blind phase refer to comparisons of changes from baseline between V (vehicle) and T (tretinoin) groups. Values for p in open phase refer to comparisons to baseline. For explanation of V and T see Table I and text. BL. Baseline (pretherapy); N, number of patients evaluated in each treatment regimen at each time point; MOS, months of study duration (first 4 months were performed in double-blind design! whereas the remaining 18 months were open-label). 0.05
r,
age developed by the Statistical Research Laboratory at The University of Michigan. The time points for presentation of the data were chosen to correspond with the completion of the various phases of the protocol. Original study (pretberapy to 4 montbs),These methods are described in our original article.' Open-label phases (4 to 22 months). At 10 and 22 months, data for each treatment regimen were compared with the respective pretherapy values and analyzed with the sign test (for efficacy data and discrete histologic parameters) or the paired Student t test (for continuous histologic measurements). The Wilcoxon signed-rank test was used to compare 4T with lOT data. The statistics are presented for descriptive purposes; therefore no adjustment for the number of comparisons was made. Statistical comparisons at each time-point include only those patients who remained in the study and exclude data ofpatients who withdrew before then.
Representative nature of study patients To ensure that the patients who completed the study were representative of the original cohort of 30 patients, a comparison was made of the overall response after 4 months oftretinoin therapy between the 16 patients who
went on to complete the study and the 14 who left before completion. As in our original study, overall response was determined on a scale of 1 to 5 (1 = much improved, 2 = improved, 3 = slightly improved, 4 = no change, 5 = worse). The results showed no detectable differences in improvement (p = 1.0, Wilcoxon rank-sum test) for both groups after 4T. Thus there was no evidence for the introduction of a bias in our open-label trial related to the patients' decision to continue in the study as a result of their clinical improvement or lack thereof.
RESULTS
Clinical results During the open-label phases, the mean scores for fine and coarse wrinkling and texture indicate that the improvement that occurred in our original, 4-month study was sustained (Figs. 1,2, and 3). Fine wrinkling and surface texture continued to show the most consistent improvement in the mean scores of both arms and face compared with those before therapy. As demonstrated by the changes in means from 4V to 4V + 6T and from 4T to lOT (Figs. 1 and 2), most of the alterations in the clinical indica-
632
Journal of the American Academy of Dermatology
Ellis et al. DOUBLE·BlIND
OPEN
DOUBLE·BLlND
OPEN
lJ)
~w
(I)~
~ ~3.0 ~ t7) 2.4
1~1.5
4V+ 6T 10T
~ ~1.8 -a:
4V+ 18T 22T
a:w
~
[j 1.2
~
lJ)
1.8
~
1.2
~~0.9
4V+ 6T 10T
~~0.6
0.6
N=16
**** **** **** **** ....... N==21
en 0.3
[;
4V+ 18T 22T
""'T"""........
0.0 LL~:::-JLL~~llr:::E::r:::E:::L.J~~:.lJ
A
10 MOS.
B
22 MOS.
lJ)
:::E
~w •. II: 2.0
en w 2.4 ~ ~2.0
~§1.6
i
~1.2
!i
lJ)
.. en 1.6 ~~ w CE 1.2
~wO ~ £ij .8
8
****
Zw
0.4 0.0.L-L---=-"_1.-J....---L
~
ai 0.8
c,
en 0.4
.u.L..---L_J......I...---L_J-J
o
C
V
T
N=30
0.0 l.Gt:::r::;tJ-...r:::;ti-llL-=t~U..:J~1J BL
Fig. 2. Clinical parameters of the arms over time. For explanationof symbols, see Fig. 1. N. Number of patients evaluated at each time point; one arm received each treatment regimen indicated. Mean severityvaluesare identical for texturein the openphases becausemost patients had scores of O.
Table II. Number of lentigines present on the face Patient No.
.5 31 32 36 38 39 Total
4 4 3 7 2 I 21
After 6 to 10 rno tretinoin therapy*
After 18 to 22 rno
o o
o o
2 4 1
2 4
a
"7
tretinoin therapy*
o
o
6
*p = 0.03 compared with pretherapy; sign test. Only patients with discrete, counted lentigines are included.
tors occurred during the first 6 to 10 months of tretinoin therapy. There was greater pinkness of the skin compared with the pretherapy skin color at all evaluations after tretinoin therapy had begun (Figs. I and 2). In all patients with discrete, countable lentigines, the number of lentigines was reduced after 6 months or more of tretinoin treatment (Table II); lightening of color occurred in lentigines that did not disappear. Tretinoin had no positive or negative effect on
telangiectasia and it did not induce clinically detectable dermal edema. To determine whether extending therapy beyond the 4 months of our original study is of clinical benefit despite the reduction in tretinoin concentration used in the open phase, we compared the scores for the photoaging indicators at 4T with those at lOT. On the arms after 10 months of tretinoin therapy, mean scores for fine wrinkling, texture, and coarse wrinkling were lower than the 4-month values (p == 0.0002,0.001, and 0.07, respectively). The improvement that was noted after lOT was maintained at 22T (i.e., there was no statistically significant difference in the scores of photoaging between lOT and 22T). The parallel design provided too few comparisons to perform a similar analysis for data from the face. Patients were not assigned randomly to the two concentrations of tretinoin (0.1 % and 0.05%) used in the open phases; therefore the effect ofconcentration cannot be definitively assessed and an optimal treatment regimen cannot be determined from our data. Nevertheless, for descriptive purposes, we have examined the mean scores for the nine patients who
Volume 23 Number 4, Part 1 October 1990
Prolonged tretinoin for photoaging
Fig. 3. A, Before tretinoin therapy (after 4V). B, After 6 months of tretinoin treatment. C, After 18 months of tretinoin therapy. All photographs were taken with a Nikon F3 35 mm camera with a Nikon 105 mm micro-Nikkor lens bracketed at F 11 to F16 using Kodachrome 25 ASA professional film with side lighting, which was positioned in standard fashion by measurement to within 1 em. Blue background was changed to black after the first picture. Photographs were obtained only to document clinical changes and were not used for data collection or analysis; all data were obtained from direct observations of patients.
633
634
Journal of the American Academy of
Ellis et al.
Dermatology
Fig. 4. Representative photomicrographs of skin from forearms. A, Before therapy, demonstrating a woven stratum corneum with minimal cytologic atypia in epidermis normal in thickness for the forearm, and moderate elastosis in papillary dermis. B, After 4 months of tretinoin therapy, showing compaction of the stratum corneum, thicker epidermis without cytologicatypia, and slight elastosisin papillary dermis. C, After 10 months of tretinoin therapy, demonstrating findings similar to 4-month specimen, with thickness of the epidermis greater than that before therapy but lessthan at 4 months, and slight dermal elastosis. D, After 22 months, similar to the IG-monthspecimenbut with moderate dermal elastosis. Variability in dermal elastosis is due to individualvariation and not the result of therapy; there were no consistent changes in the dermis that could be observed by light microscopy. (A, B, C, and D, Hematoxylin-eosin stain; X50.)
received tretinoin 0.05% daily and the 11 patients who received tretinoin 0.1 % daily in the initial open phase lasting 6 months. The differences in the mean scores for the photoaging parameters between the two groups were clinically insignificant (differences of 0.02 to 0.30 units) at both 4V + 6T and lOT. There was no difference in adverse effects between the two groups.
i\dverse effects Episodic peeling, dryness, and erythema were the only side effects detected during the 22 months of this study; these were relieved by reducing the frequency of tretinoin application or by avoiding application of the medication to the area of reaction for a few days. Only one patient used a topical cortico-
steroid once for 2 days during the open-label phases. The side effects were generally limited to the antecubital fossa and the neck; biopsy specimens were not obtained from areas exhibiting side effects.
Histologic results Before tretinoin therapy, the stratum corneum exhibited a woven pattern (Fig. 4) in 94% of forearm biopsy specimens. After 4 months of tretinoin treatment, 89% of the samples of stratum corneum exhibited compaction, with a homogeneous appearance or a combination of woven and compacted corneocytes; only 11% showed a purely woven pattern. Similarly, after 6 to 10 months of tretinoin therapy, 71 % of all specimens demonstrated compaction of the stratum corneum. However, after 18 to 22
Volume 23 Number 4, Part I October 1990
months of tretinoin therapy, the stratum corneum reverted to the pretherapy condition in many patients; 69% of specimens demonstrated a wovenpattern. The number of cells in the granular layer doubled, on average, from pretherapy to the end of the study (Fig. 5). The mean epidermal thickness increased by more than one third over the pretherapy value at all time points during tretinoin therapy (Fig. 5). The number of mitotic figures in seven adjacent highpower fields peaked early during tretinoin therapy and decreased to near pretherapy levels by the end of the study. The number of specimens with two or more mitoses were as follows: zero at pretherapy; zero at 4V versus nine at 4T (p = 0.01); three at 4V + 6T and three at lOT (p < 0.05 for each compared with pretherapy); and one at both 4V + 18T and 22T (p = no significance). During tretinoin therapy, there was an increase in an alcian blue-positive substance in the epidermis and stratum corneum, although this material became less apparent after prolonged treatment. No qualitative or quantitative changes in dermal collagen were detected .
Ultrastructural results In the pretherapy specimens the stratum corneum was thick (approximately 40 cells from the granular layer to the free surface). Intracellular structural proteins of the keratinocytes were dense and irregular. Melanin was also readily apparent throughout the stratum corneum and in the epidermis, especially in the lower portions capping the nuclei of keratinocytes. At the dermoepidermal junction, anchoring fibrils were sparse. Collagen in the papillary dermis had a smudged appearance and was aligned haphazardly; nearby fibroblasts contained enlarged mitochondria and distorted endoplasmic reticulum. The samples obtained after 4 months- and 10 months of therapy were similar. In the stratum corneum, there were approximately 25% fewer cell layers, and the cells were thinner and more electrondense. A fine granular material, similar to that found in the epidermis after oral retinoid therapy and thought to be mucoid ," was seen between cells. Structural proteins in keratinocytes were thinner and more orderly. Melanin appeared less frequently throughout the keratinocyte layers and was essentially absent from the stratum corneum. Anchoring fibrils were more numerous (Fig. 6).3 Collagen with a normal-appearing structure and orientation was present in the papillary dermis and nearby fibro-
Prolonged tretinoin for photoaging 635 DOUBLE· BLIND
V
T
4V
4T
N=15 N= 15
N=12 N=9
N=8 N=8
BL
4 MOS,
10 MOS.
22 MOS.
OPEN
100·
(J)
f3
********
~ _80'
u(/')
i: ~ 60 a: u
~~
riiiEh4_
40 '
a:w o 20 -
a:: w
4V+ 1ST 22T
4V+ 6T lOT
N=15 N=15
DOUBLE·BLlND
I-I
OPEN
v
T
4V
4T
4V+ 6T 10T
4V-'1ST 22T
N=15 N=15
N=15 N=15
N=12 N=9
N=8
BL
4 MOS.
10 MOS.
22 MOS.
N=8
Fig. 5. Histologic parameters in biopsy specimens from forearms over time. For explanation of symbols see Fig. 1. For explanation of N . see Fig. 2.
blasts had normal-appearing mitochondria and endoplasmic reticulum. DISCUSSION
Our results indicate that clinical improvement was sustained when topical tretinoin therapy was applied for up to 22 months, even when the dosage or frequency of application of tretinoin was reduced. Although patients treated with the vehicle cream alone for 4 months in our original study had no discernible improvement, I therapeutic benefit occurred after they began tretinoin applications (Figs . 1 and 2). In addition, with prolonged tretinoin treatment, 71% of discrete lentigines (so-called liver or age spots) disappeared (Table II). Our results provide further support for drug-induced improvement of photoaged skin, including wrinkles, and are consistent with other clinical studies.>? We acknowledge three sources of potential bias in this study, arising from (1) the retinoid react ion experienced by some patients, (2) the unblinded nature of the open-label segment, and (3) patient attrition. The first occurred in the double-blind phase and has been discussed in detail. 1 We decided that it would not be feasible to prolong the double-blind and vehicle-controlled design of our original study. Therefore, as with all open trials, our results may be biased, presumably yield-
636 Ellis et al.
Journal of the American Academy of Dermatology
Fig. 6. Representative electron micrographs of skin from forearms. A, Before therapy; few anchoring fibrils (AF) are seen along dermoepidermal junction (BL, basal lamina). B, After 4 months of topical tretinoin therapy; anchoring fibrils (arrows) are more easily seen compared with those before therapy; collagen with normal appearance and orientation runs along bottom of figure. C, After 10 months of therapy, findings are similar to those after 4 months; anchoring fibrils are easily seen (arrows). (A, B, and C, X46,OOO.)
ing an overly favorable view of tretinoin activity. However, many of our patients had severe enough photodamage that the effects of extended tretinoin therapy could be documented by photography (Fig. 3) and show that our results cannot be due to evaluator bias alone. In addition, the microscopic and ultrastructural findings from coded specimens confirmed that retinoid-induced effects occurred in the skin. Such effects, which occurred in our study and also occur with oral retinoid therapy, include proliferation of epidermal cells," thickened granular cell layer.? presence of a mucoid substance in the epidermis's 10-12 that may be hyaluronate synthesized by keratinocytes, 13 and normalization of basal layer tonofilaments, 14, IS With regard to the introduction of a bias by patient attrition, we were concerned that only the responsivepatients may have remained in the study for its full duration whereas those with more modest results left, thereby imparting a positive bias to our re-
sults, However, a comparison ofthe overall response of the 16 patients who remained versus the 14 who departed early revealed that both groups responded equally well to tretinoin. As indicated in Figs. 1 and 2 and Table II, most clinical changes induced by tretinoin therapy were achieved by the sixth to tenth month of treatment. Certain aspects of this study may have influenced the time at which most of the benefit was recognized, including the discrete ordinal scales we used, and the reduction in both tretinoin concentration and frequency of application that most of our patients employed. Although the study was not designed to determine a precise maintenance regimen, our data indicate that the lower 0.05% concentration or alternate-day applications of tretinoin are effective in sustaining the improvements in photoaged skin generated by daily application of tretinoin 0.1 % cream. The increased pinkness of the skin that develops
Volume 23 Number 4, Part I October 1990
during tretinoin application (Figs. I and 2) generally enhances appearance. Pinkness of the skin is caused by oral retinoid therapy as wel1 16 and thus cannot be due solely to a putative contact irritation induced by tretinoin. Indeed, evidence of inflammation was lacking in biopsy specimens even of pink skin. The only problems encountered by our patients were dryness of the skin and a so-called dermatitis characterized by erythema and flaking of the stratum corneum. These reactions occur in response to oral or topical retinoid therapy'< 17 and do not represent an allergic contact or irritant dermatitis. 18 As in our original work, we carefully avoided areas of retinoid reaction when patients' skin was evaluated or subjected to biopsy. As therapy proceeded in the open-label phases, the incidence and degree of the reaction declined and in most patients disappeared; however, clinical benefit was maintained. The discordant time courses suggest that desirable retinoid activity, not side effects,'? yields improvement of photoaged skin. The reduction in the cutaneous side effects that occur with continued use of tretinoin may be related to changes in the stratum corneum. Although the character of this layer was altered early in therapy, later it reverted toward normal in most patients. The cause of this tachyphylactic response to tretinoin in the stratum corneum, despite the increase in epidermal thickness that remained constant throughout the study, is unknown. However, the return of the stratum corneum to a woven pattern may result in a more physiologic skin barrier; if so, diminished peeling and dryness and normal corneal resistance to ultraviolet irradiation and transepidermal water loss could result. As yet we have no formally gathered data regarding the prolongation of the effects of tretinoin after therapy has been stopped. However, our limited clinical experience suggests that improvement persists for at least 2 months after therapy, followed by a gradual, partial regression. These findings do not support the concept that edema contributes to the improved appearance of our patients' skin 19 because edema would be expected to subside within a few days after treatment is stopped. Our patients' skin had undergone both chronologie aging and photodamage before therapy. Because these conditions cannot be easily separated, we do not yet know whether tretinoin therapy improves both of them. Nevertheless, our histologic and ultrastructural findings indicate that tretinoin therapy causes more than esthetic improvement; it also induces anatomic changes in the epidermis and
Prolonged tretinoin for photoaging 637 papillary dermis, in all likelihood without regard to whether the skin has been changed by time or sun. REFERENCES 1. Weiss JS, Ellis C~, Headington JT, et al. Topical tretinoin improvesphotoagcd skin. A double-blind vehicle-controlled study. JAMA 1988;259:527-32, 2. Zelickson AS, Mottaz JH, Weiss JS, et al. Topical tretinoin in photoaging: an ultrastructural study. J Cutan Aging Cosmet DermatoI1989;1:41-7. 3. Woodley DT, Zelickson AS, Briggaman RA, et al. Treatment of photoaged skin with topical tretinoin increases epidermal-dermal anchoring fibrils: a preliminary report. JAMA (In press.) 4. Ellis CN, Gold RC, Grekin RC, et al. Etretinate therapy stimulates deposition ofmucus-like material in epidermis of patients with psoriasis. J AM ACAD DERMATOL 1982; 6:699-704. . 5. Cordero A Jr. La vitamina A acida en la piel senil. Actualizaciones Terapeuticas Dermatol6gicas 1983;6:49-54. 6. Kligman AM, Grove GL, Hirose R, et al. Topical tretinoin for photoaged skin. J AM ACAD DERMATOL 1986;15:83659. 7. Leyden 11, Grove GL, Grove MJ, et al. Treatment of photodamaged facial skin with topical tretinoin. J AM ACAD DERMATOL 1989;21:638-44. 8. Gillenberg A, Immel C, Orfanos CEo Retinoid-EiflufJ auf die Zellkinetik gesunder menschlicher Epidermis. Arch Dermatol Res 1980;269:331-5. 9. Jablonska S, Wolska H, Dabrowski J, et al. Aromatic retinoids in psoriasis: clinical, histological, histochemical, electron microscopical and immunological investigations. In: Orfanos CE, Braun-Falco 0, Farber EM, et aI., eds. Retinoids: advances in basic research and therapy. Berlin: Springer-Verlag, 1981:165-73. 10. Orfanos CE, Runne U. Tissue changes in psoriatic plaques after oral administration of retinoid. Dermatologica 1978; 157(suppll):19-25. 11. Kanerva LO, Johansson E, Niemi K-M, et al. Epiderrnodysplasia verruciformis. Clinical and light- and electronmicroscopic observations during etretinate therapy. Arch Dermatol Res 1985;278:153-60. 12. Elias PM. Epidermal effects of retinoids: supramolecular observations and clinical implications. J AM ACAD DERMATOL 1986;15:797-809. 13. Tammi R, Ripellino JA, Margolis RU, eta!. Hyaluronate accumulation in human epidermis treated with tretinoin in skin organ culture. J Invest Dermatol 1989;92:326-32. 14. Lauharanta J, Niemi K-M, Lassus A. Treatment of Darier's disease with an oral aromatic retinoid (Ro 109359): a clinical and light and electron microscopic study. Arch Derm Venereol (Stockh) 1981;61:535-42. 15. Schultz-Ehrenburg U, Orfanos CEoLight and electron microscopic changes of human epidermis under oral retinoid treatment. In: Orfanos CE, Braun-Falco 0, Farber EM, et al., eds. Retinoids: advances in basic research and therapy. Berlin: Springer-Verlag, 1981:85-92. 16. Ellis CN, Voorhees JJ. Etretinate therapy. J AM ACAD DERMATOL 1987;16:267-91. 17. Silverman AK, Ellis CN, Voorhees JJ. Hypervitaminosis A syndrome: a paradigm of retinoid side effects. J AM ACAD DERMATOL 1987;16:1027-39. 18. Esmann J, Griffiths CEM, Talwar HS, et al. Biochemical and immunological characterization of the "retinoid reaction" in normal human skin [Abstract]. Clin Res 1989; 37:349A. 19. Ellis CN, Weiss JS, Hamilton TA, et al. Topical retinoic acid for photoaged skin: in reply. JAMA 1988;259:3271-4.