Adolescents’ self perceived acne-related beliefs: from myth to science,

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Anais

Brasileiros

de

Dermatologia

www.anaisdedermatologia.org.br

INVESTIGATION

Adolescents’

self

perceived

acne-related

beliefs:

from

myth

to

science

夽,夽夽

Milica

Markovic

a,∗

_,

_Ivan

_Soldatovic

b

_,

_Milan

_Bjekic

c

_,

_Sandra

_{Sipetic-Grujicic}

d

a_Department_for_Facial_Dermatoses,_City_Institute_for_Skin_and_Venereal_Diseases,_Belgrade,_Serbia

b_Institute_for_Medical_Statistics_and_Informatics,_Faculty_of_Medicine,_University_of_Belgrade,_Belgrade,_Serbia c_Department_of_General_{Dermatovenereology,}_City_Institute_for_Skin_and_Venereal_Diseases,_Belgrade,_Serbia d_Institute_of_{Epidemiology,}_Faculty_of_Medicine,_University_of_Belgrade,_Belgrade,_Serbia

Received16October2018;accepted19February2019 Availableonline26October2019

KEYWORDS Acnevulgaris; Adolescent; Perception

Abstract

Background: Acnevulgarisisrecognizedasthethirdmostprevalentskindiseaseworldwide, withhighestprevalenceamongadolescents.Beliefsandperceptionsofadolescentsaboutacne areincoherentintheliterature.

Objectives: Toassessthemostfrequentlyreportedacne-relatedbeliefsinadolescentsinorder tofocusonmisconceptionsanddevelopproperrecommendations.

Methods: A cross-sectional community-based study on representative sample of 2516 schoolchildren was conducted insix randomly selected secondaryschools inBelgrade, Ser-bia.Onlyschoolchildrenwith presentorpastacnehistoryparticipated.Factorsbelievedto aggravateorameliorateacnewererecordedandanalyzed,andthecomparisonsbetweengirls andboyswereevaluatedusingPearson’schi-squaredtest.

Results: Atotalof1452schoolchildrenwithacneparticipated,aged14---18years,amongthem 801(55.2%)girlsand651(44.8%)boys.Boyssigniﬁcantlymorefrequentlybelievedthat sweat-ing, exercise, and dairy foods aggravate acne, whereas girls signiﬁcantly more frequently blamedemotional stress,sweets, fattyfoods, sun,andlackofsleep. The topfour amelio-rationfactorswereasfollows:comedoneextraction,healthydiet,sunexposure,andincreased waterconsumption.Acneregressionwasmorefrequentlyperceivedtobelinkedwithcigarettes inboys,butwithsunexposureandweightlossingirls.

夽 _How_to_cite_this_article:_Markovic_M,_Soldatovic_I,_Bjekic_M,_{Sipetic-Grujicic}_S._{Adolescents’}_self_perceived_acne-related_beliefs:_from

mythtoscience.AnBrasDermatol.2019;94:684---90.

夽夽_Study_conducted_at_the_Institute_of_{Epidemiology,}_University_of_Belgrade,_Belgrade,_Serbia. ∗_{Corresponding}_author.

E-mail:drmilicadermatolog@gmail.com(M.Markovic).

https://doi.org/10.1016/j.abd.2019.02.005

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Studylimitations: Thenarrowagespanofadolescents(14---18years)andexclusionofacne-free adolescentsarelimitationsduetostudydesign.

Conclusion: Thissurveyispartoftheﬁrstepidemiologicalstudyonarepresentativesample inthe WesternBalkanregion. Thesigniﬁcance ofthemostfrequent acne-relatedbeliefs is discussedandmythsaboutacnearehighlighted.

Introduction

Acnevulgarisisrecognizedasanalmostuniversalcutaneous

disease, the third most prevalent skin disease

world-wide,withhighestprevalenceamongadolescents,ranging

between 40% and 70%.1 _Apart _from _a _few _small-scale

studies focused on quality of life issues, and one

Croat-ian study based on knowledge gaps in acne patients and

physicians,basicepidemiologicalstudiesonrepresentative

samples of adolescents withacne in the countriesof the

Western Balkans have not been performed yet.2---4

Stud-iesbased onbeliefs and perceptionsregarding acne have

involved either only acne patients/adolescents5---9 _or _all

students/schoolchildreninthecommunitysetting10---13_;_the

latterarepurposelyconductedtoassessthegeneral

knowl-edge onacne and treatment-seeking behavior. Their idea

ismainlytotargetthespeciﬁcvulnerablepopulationwith

tailor-madeeducational programs by clarifying the myths

and misconceptions about acne. The present research is

a community-based study on a representative sample of

adolescents with self-evaluated acne; their beliefs about

possible factors that may contribute to acne aggravation

or amelioration are analyzed. The idea is to summarize,

classify,discuss,andcorrelatethosefactorswiththe

objec-tive,evidence-basedbackground ofeachspeciﬁcreported

belief.Moreover, thesimilarities and differencesin

acne-related beliefs between adolescents here in the Western

Balkanregionand worldwidearesomewhat expectedand

are alsoincluded in study design, but represent the

sec-ondaryaim ofthe survey.The primarygoalis tocompare

themost frequentlyreportedbeliefs of theseadolescents

withavailable evidence-basedliteraturein ordertofocus

onmisconceptionsandacquireproperrecommendationsfor

health-related behavior in adolescents with acne of this

region.

Methods

The wider protocol ofpresent study waspreparedin

col-laborationwiththeInstituteofepidemiology,Universityof

Belgrade,andthesurveyencompassedacne-relatedaspects

of epidemiology, risk factors, quality of life assessment,

therapy-seeking behavior, and beliefs and perceptions of

schoolchildreninBelgrade,Serbia.

Participants

TheethicscommitteeoftheFacultyofMedicineofthe

Uni-versityofBelgradeapprovedtheproposedstudydesign.A

cross-sectional surveyof schoolchildren aged 14---18 years

was carried out during three consecutive winter months,

fromDecember2012 toFebruary 2013. Allschoolchildren

attendingsix randomlyselected secondary schools in

Bel-gradewereinvitedthroughschoolandparents’boards,as

wellaspersonallyby the researchteamduringthe initial

phase.When adjusted for prevalence rates of adolescent

acne of approximately 40---70% and a suggested response

rateof80%, therepresentative sampleof surveyed pupils

equaledapproximately2500children.Writtenconsentsfrom

bothparentsandchildrenweremandatoryandthe

enroll-mentforstudywasonvoluntarybasis.

In order to select participants for the present study,

thisstudyengagedonlyschoolchildrenwithpresentand/or

pastacne history, using thecriterion ‘‘haveyou ever had

acne?’’ Schoolchildren with negative answers (‘‘never’’)

wereexcludedandonlythe‘‘acne’’groupparticipated.

Questionnairesandassessmentofacne

Selectedquestionnaireincludedonlyacne-relatedquestions

--- present and past history of acne, and perceived acne

triggeringandaggravatingfactors.Allquestionsabout

per-ceivedfactorsweredesignedwiththreepossibleanswers:

‘‘yes,’’‘‘no,’’and‘‘notexposed.’’Whenfurtheranalyzed,

‘‘notexposed’’ were excluded, so that ‘‘yes’’ and ‘‘no’’

answersequaled100%for each factor.Atotalof16

ques-tionsforaggravatingandeightforamelioratingfactorswere

included.

Statistics

Fordescriptivepurposesdata werepresented asnumbers

withpercentages.Thecategoricalvariablesweredescribed

usingfrequencycharts.Comparisonsbetweengirlsandboys

wereevaluatedusingPearson’schi-squared testwith

con-tinuitycorrection.The adopted signiﬁcancelevel was5%.

Signiﬁcantvalues (p<0.05;p<0.01; p<0.001)were listed

inthefootnotesoftheﬁgures.

Results

Schoolchildreninallsixschoolswereinvited(2833pupils);

of them, 2521 were willing to participate (89% response

rate).However,duringfurtherevaluation14questionnaires

weremissing,thustheﬁnalsamplesizewas2516pupils.The

majoritywerebetween15and17yearsofage,andabout

one-third(29.7%)ofpupilswere16yearsofage.

Forthe purposes of the present study,a total of 1452

schoolchildren(57.7%ofallparticipants)withpresent/past

historyofacnewereenrolled,amongthem801(55.2%)girls

(3)

Total Boys Girls Cosmetics/make up

Premenstrual flare

Infrequent face wash Stress∗∗∗ Sweating∗∗∗ Sun exposure∗∗ Diary∗∗ Sweets∗∗∗ Greasy food 0 10 20 30 40 50 60 70 80 90

% frequency of reported belief Exercise

Tobacco

Alcohol

Coffee Less sleep hours∗

42,3 84,6 21 36,1 41,9 49 10,1 13,4 21,8 7,2 5,1 4,9 1,6 1,4 1,7 47,6 41,7 42 53,7 45,4 18,4 8,9 8,3 4,9 34 23,8 29,2 44,1 5,8 15,3 10,9 11,6 8,1 39,8 6,4 26,9

Figure1 Sex-baseddifferencesinself-perceivedfactorswhichaggravateacneamongschoolchildrenwithacne(n=1755).Mean

valuesfortotalboysandgirlsaregiveninbothcolumnsandnumbers(percentages).Thechi-squaredtestwasusedtodetermine sex-baseddifferencesinreportedfrequencies,labeledwith*p<0.05;**p<0.01;***p<0.001.

Perceivedfactorsthataggravate/ameliorateacne

The top four factors believed to aggravate acne in all

surveyed pupils with acne were as follows: excessive

sweating,infrequentfacewashing,consumptionofsweets,

and emotional stress; in all categories except for face

washing,genderorientedanswershadhighlysigniﬁcant

dif-ferences,aspresentedinFig.1.Ingeneral,boyssigniﬁcantly

more frequently believed that sweating (53.7%), exercise

(25.9%), and dairy foods (8.3%) aggravate acne, whereas

girlssigniﬁcantlymorefrequentlyblamedemotionalstress

(47.6%),sweets (44.1%), fatty foods (29.2%),sun (15.3%),

and lack of sleep (11.6%) for acne worsening. A selected

female-orientedquestionrevealed thatpremenstrual ﬂare

isrecorded in 84.6%of girls withacne, and ina question

about ‘‘cosmetics/make up use’’ that wasanswered only

by girls, 42.3% believed that regular use of make-up and

beautifyingskincareaggravatetheiracne.

The frequencies of reportedacne ameliorationfactors

arepresentedinFig.2.Themajorityofpupilsbelievedin

thebeneﬁtsofcomedoneextraction,i.e.,acnetreatment

ledbya nursepractitioner,withnosex-based difference.

The other most prevalent overall reports onameliorating

factorswereasfollows,accordingtodecreasingfrequency:

diet change tohealthierbehavior,ultraviolet-A/sun

expo-sure, and increasedwater consumption (‘‘when hydrated

more’’). Girls and boys shared this order of frequencies,

althoughboysequallyfrequentlydemonstratedthatwater

consumption (23%) and being out of school on holidays

(23.3%)amelioratedtheiracne,thelatterwasreportedby

34%ofgirlsaswell.Boysalsomorefrequentlyassumedthat

cigarettescouldamelioratetheiracne(17.3%).Inturn,girls

were moreconvinced of beneﬁcial effects ofexposure to

sun/UVA(40.4%)andlosingweight(22%)ontheiracne.

Studylimitations

One important limitation is the age span of adolescents,

whichwaslimitedtohighschoolpupilsof14---18yearsold,

thusearlyandlateadolescencearenotincluded.Moreover,

beliefs onacne ameliorating/aggravating factor were

col-lectedonlyinadolescentswithacne,inordertotargettheir

speciﬁc misconceptions;the opinionsof acne-free

(4)

Tobacco∗∗∗

Gaining weight

Loosing weight∗

On holidays∗∗∗

When hydrate more∗∗∗

Sun-UVA∗

Diet change∗∗∗

Cosmetic treatment

% frequency of reported behief

Girls boys total

4,1 5,6 22 34 36 40,4 48,7 62,4 17,3 11,4 5,9 5,7 14,4 18,7 23,3 29,4 30,4 32,6 37,6 36,6 43,5 58,5 61,1 23

Figure2 Sex-baseddifferencesinself-perceivedfactorswhichameliorateacneamongschoolchildrenwithacne(n=1755).Mean

valuesfortotalboysandgirlsaregiveninbothcolumnsandnumbers(percentages).Thechi-squaredtestwasusedtodetermine sex-baseddifferencesinreportedfrequencies,labeledwith*p<0.05;***p<0.001.

Discussion

AdolescentssurveyedinGreece,Turkey,andWesternEurope

believe that exacerbation factors of acne rely on diet,

inappropriate hygiene, and hormonal changes; they then

subsequently blame stress and infection, and lastly

cos-metics/make up and sweating.9,12---14 _The _analysis _of _acne

exacerbation factors in the present study revealed that

nearlyhalf of allfemale respondents (47.6%) andslightly

morethan 1/3of allparticipants believed thatemotional

stresstriggersacne.Theirbidirectionalrelationshipis

evi-denced;stressmightwellbetheconsequenceofacne,15_but

alsostressandanxietycausedbylifeeventsmayaggravate

acne, especially inﬂammatory lesions in males.16,17 _There

issubstantialevidenceaboutstress-relatedneuroendocrine

regulationofthesebaceousglandsanditsroleinthe

patho-genesisofacne.18

However, slightly more than half of the male

respon-dents in this study blamed sweating and one-quarter

of them blamed exercise for acne exacerbation, which

has been reported in similar studies on adolescents

and young adults.19,20 _Sweating _itself _isn’t _involved _in

the etiopathogenic cascade of truncal acne, but the

circumstances in which sweating occurs, such as

humid-ity, prolonged maceration of the stratum corneum, and

occlusion by clothes may contribute to occlusion of the

pilosebaceousducts.Nonetheless,arandomizedpilotstudy

onmalesfailedtoobtaintheexpectedworseningeffectof

sweatingontruncalacne.21 _The_evidence_regarding

exces-sivesweatingandacnearelackingandremaininconsistent.

The evidence for the role of improper or insufﬁcient

facial hygiene in acne pathogenesis is mostly of poor

quality.14 _{Nevertheless,} _infrequent _face _washing, _as _the

second most commonly reported aggravating factor in

this study, is also ﬁrmly established in literature reports

worldwide.5,13,22,23 _When _analyzing _acne _and _control

sub-jects, Ghodsi et al.24 _did _not _demonstrate _a _difference

betweenthosegroupsintermsoffrequency offace

wash-ingsoruseofcleansers/soapsinsteadofclearwater.Still,

there is evidence that in those with acne, washing with

cleanser twicedaily is an appropriatemeasure for better

acneclearancewithnoirritation.25

Despitethefactthattherelationofacnewithdietwas

largelyconsideredasamyth,aneweraofresearchatthe

beginningof the millennium provideda revised andmore

criticalviewpoint,anddebateregardingtheexactnutrients

thatinﬂuenceacne pathogenesisisongoing.26---28

Nonethe-less,food-relatedacne beliefs haveremained unchanged,

and have not been inﬂuenced by general dermatologic

guidelines.29,30_In_the_present_study,_the_most_reported

con-sumables/factorswerethefollowing, indecreasing order:

dietarychange,sweets,increasedwaterconsumption,fatty

foods,softdrinks,anddairy.Sweets,fattyfoods,andchange

indietary habitstowardshealthierfood werestatistically

morefrequentlyreportedbygirlscomparedtoboys,

simi-larlyasreportedamongGreekadolescents.9_The_acnegenic

propertiesofbothhyperinsulinemicfoodsandconsumption

ofdairyproteins, whichincreaseconcentrations ofinsulin

andinsulin-likegrowthfactor (IGF-1),havebeenproposed

byMelniketal.31_Although_Kaymak_et_al.32_did_not_observe

correlation of acne with serum glucose and insulin,

sev-eral other studies conducted by groups of authors30,33,34

revealed that the dietary glycemic index (GI), saturated

fat, trans-fat,and milkmay inﬂuence or aggravate acne,

andtheroleofmilkisfurtheracknowledgedbytheItalian

group.35 _In_the_present_study,_dairy_products_were_not

rec-ognizedasasigniﬁcantacne-aggravatingfactor.Incontrast,

weightlosswasrecognizedasaamelioratingfactoramong

almostone-ﬁfthofparticipants.Althoughcertainstudies20,35

havedemonstratedthatincreasedbodymassindex(BMI)is

describedasanacneriskfactorandthereisevidencethat

(5)

etal.37 _found_this_correlation _only_in_overweight_(BMI_>₂₅₎ andobese(BMI>30)girls.

Exposure to sun asan aggravatingfactor was

approxi-matelythreetimeslessfrequentlyreportedthanbeneﬁcial

effectofboth sun andartiﬁcialUVA (sunbeds)in the

sur-veyedschoolchildrenwithacne.Controlledclinicaltrialson

thetherapeutic effectofsunlight inacne arelacking.14,38

Short-term beneﬁcial effects are due to tanning-related

camouﬂageandthe fasterhealingofinﬂammatory lesions

causedbyUV-inducederythema.However,long-term

come-dogenic (sebum squalene peroxidation) and carcinogenic

effectsaremoreevidence-basedandclinicallyrelevant.39

The inﬂuence of smoking was moderately frequently

reported;17.3%ofboysvs.11.4%girlsrecognizedits

amelio-ratingeffects,whichisnotinaccordancewiththestudyby

Romboutsetal.,40_where_duration_and_extent_of_smoking_was

correlatedwith regression of papulopustular acne in girls

only.Similarly,aFrenchsurvey41 _conducted_on_adolescents

and young adults concluded that smoking more than ten

cigarettesadaywashighlyassociatedwithhavingnoacne.

Still, no relevant associations have been found by other

authors.42,43 _Alcohol _consumption _had _very _low _reported

ratein thepresent study(5.1%), thesame asobservedin

Portugueseadolescents,44 _which_is_among_lowest _reported

amongsimilarstudies.13,45_The_role_of_alcohol_in_the

patho-physiologyofacneisunclear,butalifestylewhichincludes

higher alcohol consumption might have some relation to

acne,althoughnotyetinvestigated.

Surprisinglyhighnumberofboys(58.5%)andgirls(62.4%)

in this study believed in the curative effect of cosmetic

treatment, namely comedone extraction. This physical

methodiswidely used,buttheevidenceof itsefﬁcacyin

peer-reviewed journals is scarce.46 _Recently, _an _increase

in quality-of-lifeparametershasbeen detectedin women

(19---29 years)whohave undergone some sortof cosmetic

treatmentforacne.47

Almost30% ofall participantsbelieved that theiracne

got better when they spent a substantial time out of

school, when on holidays. The authors hypothesize that

the beneﬁcial ‘‘holidays’’ effect is actually

multifacto-rial, relying on factors such as decreased anxiety,a diet

tendingtowardshealthierservings,andavoidanceofsleep

disturbances.

‘‘Cosmetics and make up’’ as an exacerbating factor

amongthesurveyedgirlshereinwasquitesimilarlyreported

in Korean acne sufferers, but was higher than reported

beliefsinsurveysconductedonbothgirlsandboys.9,12_The

comedogenic properties of cosmetics arewell supported;

moreover, across-sectionalstudy on140girls inSriLanka

signiﬁcantly correlatedexposure to at least onecosmetic

itemandacnegrade.48

Inadequate duration of sleep was reported to

aggra-vate acne in 40.2% of Saudi males,22 _and _if _proper,

sleep was recorded to ameliorate acne in 32% of Greek

schoolchildren.9 _In _the _present _study,_acne _triggering _due

to lack of sleep was determined in 10% of participants.

Sleep disorderswere not studied in terms of relationship

withacne,exceptin aFrenchstudy49 _on_a _{representative}

sample of adolescentsand young adults where univariate

analysisdidnotrevealanysigniﬁcantdifferencesbetween

thenumberofhoursofsleepandthequalityofsleepamong

the acne and control groups, but did determine a higher

riskofdifﬁcultyfallingasleepandfeelingtireduponwaking

upamongthosewithacne.

Table1 Summary ofthe mostfrequently reported acne-relatedbeliefs in thepresent study and their concordance with

evidence-basedliterature.Recommendationsforproperbehavior,whereapplicable. Acne-relatedbelief Inﬂuenceonacnein

surveyedadolescents

Commentandevidence-based recommendation

Mainreference

Sweating,exercise Triggers Individuallybased,NS PoliFetal.,19_Short_RW

etal.21

Inadequatefacewash Triggers Washtwicedailywithcleanser ChoiJMetal.,25_Magin

etal.14

Emotionalstress Triggers Provenbidirectional

relationship

ChiuAetal.,16

YosipovitchGetal.17

Dietarychangetowards healthierfoods

Improves Recentlysupported BurrisJBetal.,30_Melnik

etal.,31_Tan_et_al.1

Diet---sweets Triggers Dietarycounseling BurrisJBetal.,33_Ghodsi

etal.,24_Suh_DH_et_Kwon

HH28

Cosmetictreatment(comedo extraction)

Improves Insufﬁcientevidence ---supportsmedicaltherapy

TaubAF,46_Chilicka_K

etal.47

Sun,UVA Improves NScomedogenesisand

carcinogenesis

Zouboulisetal.,38_De

LucaCetal.39

Drinkingwater Improves Notinvestigatedelsewhere

Premenstrualﬂarea _Triggers _Highly_probable,

dermocosmeceuticalsefﬁcient

Ghodsietal.,24

Saint-JeanM50

Cosmeticsa _Triggers _Avoid_cosmetics_when_prone_to

acne

PereraMPNetal.48

a_Girls_only.

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Premenstrual ﬂareof acne has been usuallystudied in

womenwithadultacne.Inadolescentgirls,Ghodsietal.24

demonstratedthatthepremenstrual phaseisan acnerisk

factor (p<0.015); moreover, reports on beliefs show a

frequency of 22---61% among girls with acne,44,45 _so _the

exceedinglyhighlevelreportedinthepresentstudy(84.6%)

warrantsfurtherresearchonadolescentgirlsinthisregion.

Dermocosmeticsareproventobeeffectiveinamelioration

ofﬂareup.50

Conclusion

Simplecomparisonbetweentheperceptionsofyouthsinthis

countryandelsewhereregardingstudiesalsobasedonlyon

adolescentswithacne,5,6,8,9_dating_back_to_1983,_objectively

revealedsome similaritiesaswellasmajordisagreements

in adolescents’perspectives. However,it is believed that

theconcordanceofestimatedacne-relatedperceptionswith

objectiveliteraturedataregardingspeciﬁcfactorsthatmay

inﬂuenceacneaggravationoracneregressionismore

appli-cableforhealthcareeducationalprogramsandreforms,and

moreover, they could be implemented in an ofﬁce-based

dermatologist-oriented approach. Summarized

recommen-dationsforadolescentswithacneaccordingtothepresent

researchrelatedtothesupporting scientiﬁcliteratureare

listedinTable1.

Totheauthors’knowledge,thisistheﬁrst

epidemiolog-icalstudy onrepresentativesample intheWesternBalkan

region.Themainadvantageofthepresentstudyisthefact

thatthesigniﬁcanceofacnetriggeringorameliorating

fac-torsispresentedfromtheperspectiveofavailableacademic

researchand is focused ontheperceived beliefs of those

whoareaffectedwiththedisease.Furthereffortsinwhole

regionareneededtobuildasolidframeworkofinvestigative

studiesonadolescentswithacneintheWesternBalkans.

Financial

support

Nonedeclared.

Author’s

contributions

Milica Markovic: Approval of the ﬁnal version of the

manuscript;conceptionandplanningofthestudy;

elabora-tionandwritingofthemanuscript;obtaining,analyzingand

interpretingthedata;effectiveparticipationinresearch

ori-entation;intellectualparticipationinpropaedeuticand/or

therapeuticconductofthecasesstudied;criticalreviewof

theliterature.

IvanSoldatovic:Statisticalanalysis;obtaining,analyzing

andinterpretingthedata;criticalreviewofthemanuscript.

Milan Bjekic: Conception and planning of the study;

obtaining, analyzing and interpreting the data; critical

reviewoftheliterature.

SandraSipetic-Grujicic:Conceptionandplanningofthe

study;criticalreviewoftheliterature;criticalreviewofthe manuscript.

Conﬂicts

of

interest

Nonedeclared.

Acknowledgements

SupportedbyMinistryofScienceandTechnologyGrantNo.

175042.

References

1.TanJKL,BhateK.Aglobalperspectiveontheepidemiologyof acne.BrJDermatol.2015;172Suppl.1:3---12.

2.PerićJ,MaksimovićN,JankovićJ,MijovićB,ReljićV,Janković S.Prevalenceandqualityoflifeinhighschoolpupilswithacne inSerbia.VojnosanitPregl.2013;70:935---9.

3.ReljićV,MaksimovićN,JankovićJ,MijovićB,PerićJ,Janković S.Evaluationofthequalityoflifeinadolescentswithacne. VojnosanitPregl.2014;71:634---8.

4.BrajacI,Bili´c-ZulleL,Tkalci´cM,LoncarekK,GruberF.Acne vulgaris:mythsandmisconceptionsamongpatientsandfamily physicians.PatientEducCouns.2004;54:21---5.

5.TallabTM.Beliefs,perceptionsandpsychologicalimpactofacne vulgarisamongpatientsintheAssirregionofSaudiArabia.West AfrJMed.2004;23:85---7.

6.TanJK,VaseyK,FungKY.Beliefsandperceptionsofpatients withacne.JAmAcadDermatol.2001;44:439---45.

7.RasmussenJE,SmithSB.Patientconceptsandmisconceptions aboutacne.ArchDermatol.1983;119:570---2.

8.KaushikM,GuptaS,MahendraA.Livingwithacne:beliefand perception ina sampleof Indianyouths. IndianJDermatol. 2017;62:491---7.

9.RigopoulosD,GregoriouS,IfandiA,EfstathiouG,GeorgalaS, ChalkiasJ,etal.Copingwithacne:beliefsandperceptionsina sampleofsecondaryschoolGreekpupils.JEurAcadDermatol. 2007;21:806---10.

10.YahyaH.AcnevulgarisinNigerianadolescents---prevalence, severity, beliefs,perceptions, and practices.IntJDermatol. 2009;48:498---505.

11.Smithard A, Glazebrook C, Williams HC. Acne prevalence, knowledge about acne and psychological morbidity in mid-adolescence: a community-based study. Br J Dermatol. 2001;145:274---9.

12.UsluG,SendurN,UsluM,SavkE,KaramanG,EskinM.Acne: prevalence, perceptions and effects on psychological health among adolescents in Aydin, Turkey. J Eur Acad Dermatol Venereol.2008;22:462---9.

13.Karciauskiene J, Valiukeviciene S, Stang A, Gollnick H. Beliefs,perceptions,andtreatmentmodalitiesofacneamong schoolchildreninLithuania:across-sectionalstudy.IntJ Der-matol.2015;54:e70---8.

14.MaginP,PondD,SmithW,WatsonA.Asystematicreviewofthe evidencefor‘mythsandmisconceptions’inacnemanagement: diet,face-washingandsunlight.FamPract.2005;22:62---70.

15.DunnLK,O’NeillJL,FeldmanSR.Acneinadolescents:qualityof life,self-esteem,mood,andpsychologicaldisorders.Dermatol OnlineJ.2011;17:1.

16.ChiuA,ChonSY,KimballAB.Theresponseofskindiseaseto stress:changesintheseverityofacnevulgarisasaffectedby examinationstress.ArchDermatol.2003;139:897---900.

17.YosipovitchG1,Tang M,DawnAG,ChenM, GohCL,HuakY, etal.Studyofpsychologicalstress,sebumproductionandacne vulgarisinadolescents.ActaDermVenereol.2007;87:135---9.

(7)

18.ZouboulisCC,BöhmM.Neuroendocrineregulationofsebocytes ---apathogeneticlinkbetweenstressandacne.ExpDermatol. 2004;13Suppl.4:31---5.

19.PoliF,AuffretN,BeylotC,ChivotM,FaureM,MoyseD,etal. Acneasseenbyadolescents:resultsofquestionnairestudyin 852Frenchindividuals.ActaDermVenereol.2011;91:531---6.

20.ParkSY,KwonHH,MinS,YoonJY,SuhDH.Epidemiologyandrisk factorsofchildhoodacneinKorea:across-sectionalcommunity basedstudy.ClinExpDermatol.2015;40:844---50.

21.Short RW, Agredano YZ, Choi JM, Kimball AB. A single-blinded, randomized pilot study to evaluate the effect of exercise-induced sweat on truncal acne. Pediatr Dermatol. 2008;25:126---8.

22.Al-HoqailIA.Knowledge,beliefsandperceptionofyouthtoward acnevulgaris.SaudiMedJ.2003;24:765---8.

23.Su P, Chen Wee Aw D, Lee SH, Han Sim Toh MP. Beliefs, perceptionsand psychosocialimpact ofacne amongst Singa-poreanstudentsintertiaryinstitutions.JDtschDermatolGes. 2015;13:227---33.

24.GhodsiSZ,OrawaH, ZouboulisCC.Prevalence,severity, and severityriskfactorsofacneinhighschoolpupils:a community-basedstudy.JInvestDermatol.2009;129:2136---41.

25.ChoiJM,Lew VK, KimballAB. Asingle-blinded,randomized, controlledclinicaltrialevaluatingtheeffectoffacewashing onacnevulgaris.PediatrDermatol.2006;23:421---7.

26.FiedlerF,StanglGI,FiedlerE,TaubeKM.Acneandnutrition:a systematicreview.ActaDermVenereol.2017;97:7---9.

27.BronsnickT,MurzakuEC,RaoBK.Dietindermatology:PartI. Atopicdermatitis,acne,andnonmelanomaskincancer.JAm AcadDermatol.2014;71:e1---12,1039.

28.SuhDH,KwonHH.What’snewinthephysiopathologyofacne? BrJDermatol.2015;172Suppl.1:13---9.

29.TomWL,BarrioVR.Newinsightsintoadolescentacne.CurrOpin Pediatr.2008;20:436---40.

30.Burris J,Rietkerk W, Woolf K. Relationshipsof self-reported dietaryfactorsandperceivedacneseverityinacohortofNew Yorkyoungadults.JAcadNutrDiet.2014;114:384---92.

31.Melnik BC. Diet in acne: further evidence for the role of nutrientsignallinginacnepathogenesis.ActaDermVenereol. 2012;92:228---31.

32.KaymakY,AdisenE,IlterN,BideciA,GurlerD,CelikB.Dietary glycemicindexandglucose,insulin,insulin-likegrowth factor-I,insulin-likegrowthfactorbindingprotein3,andleptinlevels inpatientswithacne.JAmAcadDermatol.2007;57:819---23.

33.BurrisJ,RietkerkW,ShikanyJM,WoolfK.Differencesindietary glycemicloadandhormonesinNewYorkCityadultswithnoand moderate/severeacne.JAcadNutrDiet.2017;117:1375---83.

34.BurrisJ,RietkerkW,WoolfK.Acne:theroleofmedicalnutrition therapy.JAcadNutrDiet.2013;113:416---30.

35.Di Landro A, Cazzaniga S, Parazzini F, Ingordo V, Cusano F, AtzoriL,etal.Familyhistory,bodymassindex,selecteddietary factors, menstrual history, and risk of moderate to severe acne inadolescentsand young adults. JAmAcadDermatol. 2012;67:1129---35.

36.DelPreteM,MaurielloMC,FaggianoA,DiSommaC,Monfrecola G,FabbrociniG,etal.Insulinresistanceandacne:anewrisk factorformen?Endocrine.2012;42:555---60.

37.HalvorsenJA,VleugelsRA,BjertnessE,LienL.A population-basedstudyofacneandbodymassindexinadolescents.Arch Dermatol.2012;148:131---2.

38.ThielitzA,GollnickHPM.Naturalandartiﬁcialsuntanning.In: ZouboulisCC,KatsambasAD,KligmanAM,editors. Pathogen-esisand treatmentofacne and rosacea. Berlin,Heidelberg: Springer-Verlag;2014.p.185---8.

39.DeLucaC,ValacchiG.Surfacelipidsasmultifunctional medi-ators of skin responses to environmental stimuli. Mediators Inﬂamm.2010;2010:321494.

40.RomboutsS,NijstenT,LambertJ.Cigarettesmokingandacne inadolescents:resultsfromacross-sectionalstudy.JEurAcad DermatolVenereol.2007;21:326---33.

41.Wolkenstein P, Misery L, Amici JM, Maghia R, Branchoux S, CazeauC,etal.Smokingand dietaryfactors associatedwith moderate-to-severe acne in French adolescents and young adults:resultsofasurveyusingarepresentativesample. Der-matology.2015;230:34---9.

42.SchäferT,NienhausA,VielufD,BergerJ,RingJ.Epidemiology ofacne inthegeneral population:theriskofsmoking.Br J Dermatol.2001;145:100---4.

43.FiroozA,SarhangnejadR,DavoudiSM,Nassiri-KashaniM.Acne andsmoking:istherearelationship?BMCDermatol.2005;5:2.

44.AmadoJM,MatosME,AbreuAM,LoureiroL,OliveiraJ,Verde A,etal.TheprevalenceofacneinthenorthofPortugal.JEur AcadDermatolVenereol.2006;20:1287---95.

45.SuhDH,KimBY,MinSU,LeeDH,YoonMY,KimNI,etal.A mul-ticenterepidemiologicalstudyofacnevulgarisinKorea.IntJ Dermatol.2011;50:673---81.

46.Taub AF. Procedural treatments for acne vulgaris. Dermatol Surg.2007;33:1005---26.

47.Chilicka K, Maj J, Panaszek B. General quality of life of patients with acne vulgaris before and after performing selectedcosmetologicaltreatments.PatientPreferAdherence. 2017;11:1357---61.

48.PereraMPN,PeirisWMDM,PathmanathanD,MallawaarachchiS, KarunathilakeIM.Relationshipbetweenacnevulgarisand cos-meticusageinSriLankanurbanadolescentfemales.JCosmet Dermatol.2018;17:431---6.

49.MiseryL,WolkensteinP,AmiciJM,MaghiaR,BrenautE,Cazeau C,etal.Consequencesofacneonstress,fatigue,sleep disor-dersandsexualactivity:apopulation-basedstudy.ActaDerm Venereol.2015;95:485---8.

50.Saint-JeanM,KhammariA, SeiteS,MoyalD,DrenoB. Char-acteristics of premenstrual acne ﬂare-up and beneﬁts of a dermocosmetictreatment:adouble-blindrandomisedtrial.Eur JDermatol.2017;27:144---9.