Adult Acne Versus Adolescent Acne: A Retrospective Study of 1,167 Patients

Abstract

Background: Acne is predominantly known as a skin disorder of the adolescent population. However, current research indicates that the prevalence of adult patients with acne, especially among women, is increasing. Objective: The objective of this study was to evaluate differences between adults and teenagers with regard to acne prevalence, patient sex, acne severity, and quality of life. In adult patients, we considered differences in family history of acne, onset, and smoking habits. Design: We performed a retrospective study of a total of 1,167 patients with acne who attended our outpatient clinic from January 2008 to March 2015. Participants: The study population was divided into two groups: adolescent acne and adult acne. Among the adult subjects, 385 were female and 69 were male; among the adolescent subjects, 378 were female and 335 were male. Measurements: The severity of acne was recorded using the Global Acne Grading System. The impact of acne on quality of life was investigated using the Assessment of Quality of Life questionnaire. Results: Study results show that acne in female patients was more prevalent than in male patients. The evaluation of acne severity showed that "mild acne" is the most frequent form. With regard to smoking habits, time of onset, and family history of acne, we did not find any statistically significant differences between the sexes. Conclusion: In both sexes, there are some differences in adult acne versus the adolescent form. Treating adult acne demands a different approach to diagnosis and a tailored management plan that considers all of the variables involved.

Full text

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JCAD JOURNAL OF CLINICAL AND AESTHETIC DERMATOLOGY January 2018 • Volume 11 • Number 1
ORIGINAL RESEARCH
A
Acne is widely considered a chronic skin
disease that primarily aects individuals going
through puberty, with a prevalence among this
population of almost 95 percent.1 However,
although acne is principally a disorder of
adolescence, current research indicates that
the prevalence of adult patients with acne
is increasing.2 Three dierent groups of acne
patients can be considered: preadolescent,
adolescent, and post-adolescent patients.3–5 An
extensive survey carried out on a total of 1,013
men and women showed that the prevalence of
acne was 50.9 percent, 35.2 percent, 26.3 percent,
and 15.3 percent among women aged 20 to 29
years, 30 to 39 years, 40 to 49 years, and 50 years
and older, respectively.6 According to the time of
onset, two subtypes of adult acne are recognized:
persistent and late-onset. Persistent acne is
a continuation or relapse of the disease from
adolescence into adulthood and middle age,7,8
while the late onset type involves patients aged
25 years and older who have not previously been
aected by acne vulgaris. Both subtypes more
frequently aect women and are often associated
with inammation, changes in pigmentation,
and scarring. Late-onset acne is thought to be
less common than persistent acne; in a cross-
sectional study involving adult female patients
diagnosed with acne at a general dermatology
clinic, Schmitt et al9,10 reported that 80 percent
of women showed persistent acne.This latter
type of acne has been reported to be generally
mild to moderate in severity and to present with
more inammatory lesions and fewer comedones
compared to adolescent acne.7,11 It generally
aects the face, particularly the mandibular
region, the zone below the jawline, the cervical
region, and sometimes the chest.12
Adult acne pathogenesis involves several
endogenous and exogenous factors. Examples
of the former include endocrine disorders, the
chronic stimulation of innate immunity,14 and
genetic predispositions,12–14 those of the latter
include cosmetics,7–15 stress,14 and tobacco.7,8
Adult acne is a chronic condition that appears
to impact the quality of life in adult patients more
than in their younger counterparts,13–16 with
considerable psychological, social, and emotional
impacts6,17,18 and up to a 40-percent prevalence of
psychiatric comorbidity.19
Currently, adult acne treatment should be
tailored to address the specic characteristics
of this adult population, including other factors
beyond acne severity.
METHODS
Study design. We performed a retrospective
study that included 1,167 acne patients from our
database who attended our outpatient clinic from
January 2008 to March 2015.Patients aected
by “mild,” “intermediate,” and “severe” acne were
included in this study. The study population was
divided into two groups: adolescent acne (aged
12–25 years) and adult acne (aged > 25 years).
In the adult population, there were 385 women
and 69 men, while in the adolescent population,
there were 378 girls and 335 boys. A detailed
history and examination was carried out for
ABSTRACT
Background: Acne is predominantly known as a skin
disorder of the adolescent population. However, current
research indicates that the prevalence of adult patients
with acne, especially among women, is increasing.
Objective: The objective of this study was to evaluate
dierences between adults and teenagers with regard to
acne prevalence, patient sex, acne severity, and quality
of life. In adult patients, we considered dierences in
family history of acne, onset, and smoking habits. Design:
We performed a retrospective study of a total of 1,167
patients with acne who attended our outpatient clinic
from January 2008 to March 2015. Participants: The
study population was divided into two groups: adolescent
acne and adult acne. Among the adult subjects, 385 were
female and 69 were male; among the adolescent subjects,
378 were female and 335 were male. Measurements:
The severity of acne was recorded using the Global Acne
Grading System. The impact of acne on quality of life
was investigated using the Assessment of Quality of Life
questionnaire. Results: Study results show that acne in
female patients was more prevalent than in male patients.
The evaluation of acne severity showed that “mild acne”
is the most frequent form. With regard to smoking habits,
time of onset, and family history of acne, we did not nd
any statistically signicant dierences between the sexes.
Conclusion: In both sexes, there are some dierences in
adult acne versus the adolescent form. Treating adult acne
demands a dierent approach to diagnosis and a tailored
management plan that considers all of the variables
involved.
KEYWORDS: Adult acne, persistent acne, late onset acne,
risk factor, sex dierences
Adult Acne Versus Adolescent
Acne: A Retrospective Study of
1,167 Patients
by NEVENA SKROZA, MD; ERSILIA TOLINO, MD; ALESSANDRA MAMBRIN, MD;
SARA ZUBER, MD; VERONICA BALDUZZI, MD; ANNA MARCHESIELLO, MD; NICOLET-
TA BERNARDINI, MD; ILARIA PROIETTI, MD; and CONCETTA POTENZA, MD
Drs. Tolino, Mambrin, Zuber, Balduzzi, Marchesiello, Bernardini, and Proietti are with the Sapienza University of Rome, Polo
Pontino in Terracina, Italy. Drs. Skroza and Potenza are associate professors at Sapienza University of Rome, Polo Pontino.
J Clin Aesthet Dermatol. 2018;11(1):21–25
FUNDING: No funding was provided for this study.
DISCLOSURES: The authors have no relevant conicts of interest relevant to the content of this article.
CORRESPONDENCE: Nevena Skroza, MD. Email: nevena.skroza@uniroma1.it

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JCAD JOURNAL OF CLINICAL AND AESTHETIC DERMATOLOGY January 2018 • Volume 11 • Number 1
ORIGINAL RESEARCH
each patient, including the collection of data
on sex, age, acne severity, and smoking habits;
family history of acne and age of onset were
selectively investigated in the adult population.
Severity of acne was recorded using the
Global Acne Grading System (GAGS). This system
divides the face, chest and back into six areas
(forehead, left cheek, right cheek, nose, chin
and chest and back) and assigns a factor to each
area on the basis of severity.
The impact of acne on quality of life was
investigated by administering the Assessment of
Quality of Life questionnaire (AQoL) to patients.
The questionnaire scale includes 19 items
that measure factors regarding acne severity
and psychological morbidity related to the
disease. Each question in the survey is scored
using a six-point scale, with 0=remarkable
deterioration of quality of life and 6=little
deterioration of quality of life. The total score
of the questionnaire is 114 points. Measuring
the impact of acne on quality of life allows us
to understand the disease perception from the
patient’s point of view.
Statistical analysis. Quantitative data were
expressed as mean and ± standard deviation.
Chi-square (χ2) and Student’s t-tests were
used for categorical and quantitative variables,
respectively. Statistical signicance was set at
p>0.05. Statistical analyses were performed
using the Statistical Package for Social Sciences
version 21.0 software package (IBM Corp.,
Armonk, New York).
RESULTS
We retrospectively analyzed data from our
acne outpatient database. Out of the 1,167
patients suering from acne, 454 (41.3%) were
adults and 713 were adolescents (58.7%).
Among adults, female sex was more prevalent,
with 385 (85%) female patients versus 69
(15%) male patients. In the adolescents, female
patients numbered 378 (53%) versus 335 male
patients (47%) (Figure 1).
The evaluation of acne severity showed that
“mild acne” was the most frequent form in all
subgroups (92% in adult females, 82% in adult
males, 89% in teenage females, and 77% in
teenage males, respectively). Additionally, the
least frequent form was “severe acne” (1% in
adult females, 3% in adult males, 1% in teenage
females, and 1% in teenage males). Finally,
“moderate acne” was observed homogeneously
in all subgroups, though both male groups
showed a little higher prevalence of such in
comparison with the female groups (15% in
adult males and 22% in teenage males versus
7% in adult females and 10% in teenage
females) (Figure 2).
Furthermore, we considered family history
and onset of acne and in male and female adults
(Table 1). Smoking habits were investigated in
both the adolescent and adult groups. In the
total of 454 patients examined, 322 (70.9%)
patients (50 male [72.5%] and 272 female
[70.6%]) declared a family history of acne
(p=0.872). Regarding the time of onset, 321
(70.7%) out of 454 patients (43 male [62.3%]
and 278 female [72.2%]) were classied as
having “persistent” adult acne, while 133
(29.3%) out of 454 (26 male [37.7 %] and 107
female [27.8%]) presented with the “late-onset
“ type of adult acne (p=0.129). Moreover,
smoking habits were identied in 74 patients
(16.3%) (17.4% male and 16.1% female)
(p=0.068). Based on these data, we did not nd
any statistically signicant dierences in the
considered items among the sexes.
Among the adolescent subgroups, 15 of the
713 patients declared having a smoking habit.
Signicant dierences in sex distribution were
found between the adult population versus the
adolescent population in terms of smoking. In
the adult acne group, women who smoked were
more prevalent (62 women vs. 12 men), while,
in the teenager group, the prevalence of those
who smoked was similar among both sexes
(Figure 3). Data for family history, onset of acne,
and smoking habits are summarized in Table 1.
Based on the AQoL score, acne has a
signicantly negative impact on quality of life
(Figure 4), especially in the female population
(female adolescents: 45/114 points and female
adults: 35/114 points; male adolescents: 60/14
points and male adults: 70 /114 points).
FIGURE 1. Distribution of adult acne group and teenage acne group between the sexes
FIGURE 2. Acne severity among men and women in adult and teenage acne groups

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JCAD JOURNAL OF CLINICAL AND AESTHETIC DERMATOLOGY January 2018 • Volume 11 • Number 1
ORIGINAL RESEARCH
DISCUSSION
Acne is a chronic inammatory skin disease
that primarily aects the face, chest, and
back, with a prevalence of almost 95 percent
in adolescents. Several large studies have
reported a prevalence of adolescent acne
ranging from 81 to 95 percent in young men
and 79 to 82 percent in young women.20,21 Its
prevalence is increasing in the adult population
too, particularly in women, even if literature
lacks exact data on the subject. The rst study
on adult acne prevalence by Cunlie et al22
demonstrated that acne incidence was higher
among adolescent men than adolescent
women. However, Cunlie and colleagues
found that, in adults 18 years of age and older,
this prevalence decreases for both sexes, but
becomes more prevalent in adult women than
adult men. In 1999, Goulden et al23 conrmed
that clinical facial acne aects adult women
more frequently than it does men. In this study,
the prevalence of post-adolescent acne was
three percent in men and 12 percent in women
in a population of randomly selected individuals
with similar demographic characteristics. The
authors further noted that the mean age of
patients with acne increased from 20.5 years
to 26.5 years from 1989 to 1999. Moreover, 82
percent of aected people had persistent acne
subtypes. In our study, which included 454
adult patients, women were predominantly
aected (85%) compared to men (15%), while
in younger individuals (n=713), the two sexes
were similarly aected. In opposition to the
study of Cunlie et al,22 the prevalence of acne
in our study population did not decline between
the ages of 24 to 44 years, but did decrease
after the age of 45 years.23 The prevalence of
acne in adult women was also analyzed in the
study by Collier et al.6 The result of this research
showed that 50 percent of women were aected
in the third decade of life and that acne was
more common in women than in men at all
ages after age 20 years (p<0.05). Variations in
the prevalence of the disease among dierent
ethnic groups have also been reported. A study
on 2,895 women of dierent ethnicities showed
that acne was more prevalent in women with
darker skin types (African American: 37%;
Hispanic: 32%) versus in those with lighter
skin (Asians 30%; Caucasians 24%; and Indians
23%).24 Moreover, in Asians, inammatory
acne forms are more frequent than non-
inammatory forms (20% vs. 10%), whereas,
TABLE 1. Family history, onset of acne, and smoking habits and in male and female adult acne patients
RISK FACTOR TOTAL MALE FEMALE P VALUE
Family history
Yes 322 (70.9%) 50 (72.5%) 272 (70.6%)
0.872
No 132 (29.1%) 19 (27.5%) 113 (29.4%)
Onset
Persistent 321 (70.7%) 43 (62.3%) 278 (72.2%)
0.129
Late-onset 133 (29.3%) 26 (37.7%) 107 (27.8%)
Smoking habit
Yes 74 (16.3%) 12 (17.4%) 62 (27.8%)
0.068
No 380 (83.7%) 57 (82.6%) 323 (83.9%)
FIGURE 3. Among the adolescent subgroups, 15/713 patients declared having a smoking habit. Signicant dierences in sex distribution were
found in the adult population vs. the adolescent population. In the adult acne group, women who smoked were more prevalent (62 versus 12)
than men, while in the adolescent group, the prevalence of smokers was similar between both sexes.
FIGURE 4. Acne-related quality of life score is lower among participants with acne compared to those without, especially among women.
Mean AQoL: Sex Dierences

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JCAD JOURNAL OF CLINICAL AND AESTHETIC DERMATOLOGY January 2018 • Volume 11 • Number 1
ORIGINAL RESEARCH
in Caucasians, non-inammatory acne is more
prevalent (14% vs. 10%).
Based on the time of onset, two subtypes of
adult acne can be described: persistent acne and
late-onset acne. In our study, 321 (70.7%) out
of 454 patients showed persistent forms of acne,
while 133 (29/3%) out of 454 presented a “late
onset “ type of adult acne (p=0.129).
Inammation, change in pigmentation, and
scarring characterized both subtypes, albeit
there were some dierences in term of lesions
localization and therapy.
The clinical lesions of adult acne are typically
considered to be dierent than those of
adolescent acne.25 Furthermore, young men
are more aected than young women and
generally show the most severe forms of the
disease, while adult acne mainly aects women
presenting with seborrhea, comedones, and
inammatory lesions. The evaluation of acne
severity in our study showed that “mild acne”
is the most frequent form in male and female
patients of both adolescent and adult ages;
also, in all groups, the least frequent form was
“severe acne.”
Morphologically, the classical presentation of
adult acne consists of inammatory papulo-
pustular lesions in the lower half of the face.
The acne usually presents gradually and is
mild-to-moderate in severity, in contrast with
adolescent forms. In the literature, two clinical
proles of adult acne have been described.13 One
shows hyperseborrhea and non-inammatory
lesions diuse in all areas of the face with
abundant open or closed small comedones,
while the other consists of predominant
inammatory lesions, long-lasting nodules, and
cysts on the lower one-third of the face, neck,
and jawline. This latter type of presentation has
been described as “chin acne.” Capitanio et al,26
in 2010, described a new clinical presentation
of adult acne called “comedonal postadolescent
acne,” which is characterized by inammatory
lesions and large, prominent cyst-like
comedones homogeneously distributed on the
whole face with a relative absence of lesions on
the lower half of the face and jawline. Khunger
et al,27 in a study involving 280 Indian patients,
revealed that adult acne usually presents as
inammatory papules and pustules (in 83% of
patients) that are mild to moderate in severity.
Moreover, in the Indian population, comedonal
acne is rare in comparison with adolescent acne;
however, cystic acne is not uncommon and was
present in 12 percent of the patients studied.
This traditional description of adult acne was
recently revised by Dreno et al in 20149 with
an observational, prospective international
study on 374 adult female patients with acne.
The results illustrate that post-adolescent
acne is very similar in severity to adolescent
acne in up to 90 percent of women, involving
multiple areas of the face (e.g., mandibles,
temples, cheeks). In 6.4 percent of cases, the
women presented only inammatory lesions
and 17.1 percent had only comedonal acne. In
addition, only 12 percent of women presented
with lesions localized on the mandibular area.16
Truncal involvement was reported in 48.4
percent of patients, and, notably, women with
truncal acne also had multiple other body areas
aected. Other important additional clinical
features have been reported, such as post-
inammatory hyperpigmentation (commonly
present in the cheek26 [38.2%] and mandibular9
[26.1%] areas), scars, which are frequently
atrophic and present in 58.8 percent of patients
studied, particularly in women with mandibular
presentation;9 hyperseborrhoea; and erythema.
The pathogenesis of adult female acne is very
complex and remains incompletely elucidated.
Similar to adolescent acne, the pathogenesis of
adult female acne involves an interplay of excess
sebum production, abnormal keratinization
within the follicle, and bacterial colonization
of the pilosebaceous duct by Proponibacterium
acnes.28 Furthermore, hormones, the use of
cosmetics and/or drugs, and chronic stress have
been put forward as possible etiological factors.
Genetics also play a strong role; Goulden et al2
showed that the majority of patients (67%)
have a rst-degree family history of post-
adolescent acne. In our study, with respect to
the total of 454 adult patients examined, 322
(70.9%) patients (50 males [72.5%] and 272
females [70.6%]) declared a family history of
acne (p=0.872). In another study,9 job stress
was associated with more severe forms of
acne in women; women with localized acne
were also more likely to report higher stress
levels (6.0–6.4 vs. 5.1) and a psychologically
stressful job (68.6–73.6% vs. 58.8%). In this
study, it was also reported that 24.8 percent
of patients were smokers; notably, there was a
signicantly higher proportion of subjects with
severe acne among smokers in comparison
with among nonsmokers (17.4%). Smoking
has been related with abnormal follicular
keratinization and inammation through
lipide peroxidation of sebum in comedones
by inicting oxidative stress. According to the
data in our study, adult acne patients smoke
more than their younger counterparts, with
statistically signicant results in both sexes
(p<0.001).
Adult acne is mainly mild-to-moderate
in severity, but treatment failure and a
chronic, relapsing course may increase the
self perception of symptom severity with a
resulting negative impact on quality of life.
In several papers, acne severity was similar
between the two sexes but quality of life was
more impaired in women than in men.18–29
Acne duration seems to be an important factor
responsible for the worse perception of the
disease by women. Adult acne in women has
been associated with depression, anxiety,
psychological stress, and suicidal ideation.3
Moreover, Tan et al18 observed that other
factors such as increased age and longer
acne duration (> ve years) are related with
a greater impairment in quality of life in
females.
Only a few studies investigating sex
dierences in adult acne have been reported in
the literature; our study evaluates dierences
between men and women regarding acne
severity, smoking habits, family history
of acne, and time of onset. Signicant
dierences in gender distribution have been
found between the adult and the adolescent
populations. As for prevalence, adult acne is
more prevalent in women than in men, while
in adolescents, the prevalence is quite similar
in both sexes. Moreover, data about acne
severity show that “severe acne” and “mild
acne” forms are observed homogeneously in all
groups; only “moderate acne” shows a slightly
higher prevalence in male than in female
patients.
As for smoking habits, time of onset, and
family history of acne, we did not nd statistically
signicant dierences between the sexes.
Limitations. Our study presents some
limitations, in that it is retrospective and
monocentric in nature. Moreover, our clinical
evaluation was based on the GAGS without
considering the lesions and distribution patterns
of acne that can dier between sexes, according
to literature data.25

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JCAD JOURNAL OF CLINICAL AND AESTHETIC DERMATOLOGY January 2018 • Volume 11 • Number 1
ORIGINAL RESEARCH
CONCLUSION
Acne is one of the most common skin disorders
worldwide and occurs primarily at puberty with
a prevalence of almost 95 percent. Although
it is principally a disorder of adolescence,
the prevalence of adult patients with acne,
particularly adult women with acne, is increasing.
The higher prevalence of adult acne in the
female population prompted us to investigate
whether other variables could present signicant
dierences between sexes. These dierences
have recently gained attention in many branches
of medicine, including dermatology, so we
selectively addressed our interest to the dierent
forms of acne, family history of the disease, time
of onset, smoking habits, and quality of life in
both sexes. This restriction could represent a
limit of the present study but it also represents
a starting point for further research on factors
inuencing adult acne. As this study reports only
the results from our outpatient clinic, it would
be auspicable to include experiences from other
centers in order to obtain the most statistically
signicant data.
Our results agree with the literature data
on adult acne: women are aected more by
acne (85%) than men (15%); family history
represents one of the main risk factors (70%);
the persistent form of acne is more prevalent
(70.7%) than the late-onset form; mild acne is
the predominant form (87%); and there is a large
number of smokers among adults with acne than
among younger individuals with acne. Finally,
there is evidence of a negative impact of acne
on quality of life in both adult and adolescent
female patients. Some dierences of adult acne
from adolescent acne in both sexes were noted
in our study; as such, each demands a dierent
approach to diagnosis and treatment, and we
recommend a tailored management plan that
considers all of the variables involved.
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