Rodríguez-Covarrubias, R.A. Castillejos-Molina C.I. Villeda-Sandoval, M.B. Calao-Pérez, J.O. Herrera-Cáceres, E. González-Cuenca,F. Mexican adults: The importance of partneravailability Erectile dysfunction and associated risk factors amongyoung ORIGINAL

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www.elsevier.es/uromx

ÓRGANO OFICIAL DE DIFUSIÓN DE LA SOCIEDAD MEXICANA DE UROLOGÍA

ORIGINAL ARTICLE

Erectile dysfunction and associated risk factors among young Mexican adults: The importance of partner

availability

C.I. Villeda-Sandoval, M.B. Calao-Pérez, J.O. Herrera-Cáceres, E. González-Cuenca, F. Rodríguez-Covarrubias, R.A. Castillejos-Molina

^∗

DepartmentofUrology,InstitutoNacionaldeCienciasMédicasyNutriciónSalvadorZubirán,MexicoCity,Mexico

Received10March2015;accepted25June2015 Availableonline28August2015

KEYWORDS Erectiledysfunction;

Youngmale;

Riskfactor

Abstract

Objective:TodeterminetheprevalenceofEDandassociatedriskfactorsamongyoungMexicans between18and40yearsofage.

Methods:Anobservational,cross-sectional,descriptiveandanalyticstudywasconducted.Data collectionwasachievedthroughaquestionnaire.ParticipantscompletedtheUrologicHealth SurveyforMenandtheInternationalIndexofErectileFunction(IIEF-5)questionnaire.Thestudy alsoincludedsociodemographic,clinical,andsexualbehaviorvariables.

Results:Ofthe373questionnairesﬁlledout,only160wereansweredcompletelyandusedfor theanalysis.Themeanagewas25.59±5.45years.TheprevalenceofEDwas33.7%(mild17.5%, mild-to-moderate8.1%,moderate6.3%,andsevere1.9%).Themeanscorefornon-EDmales was24.38±0.94versus15.41±4.81intheEDgroup.Univariateanalysisshowedasigniﬁcant differenceintheitemsofage(p<0.01),havingastablesexualpartner(p<0.01),sleepingwith thesexualpartner(p<0.01),sexualorientation(p=0.04),andthenumberofsexualintercourse episodesperweek(p<0.01).Inthemultivariateanalysis‘‘Nothavingastablesexualpartner’’

remainedasigniﬁcantriskfactor(p=0.027,OR=2.60[CI1.11---6.08]).

Conclusions:Inourstudy,youngMexicanadultshadanEDprevalenceof33.7%andmostofthe casesweremild(17.5%).Partneravailabilitywasimportant.Noorganicvariableswererelated toED.

© 2015 Published by Masson Doyma México S.A. on behalf of Sociedad Mexi- cana de Urología. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

∗Correspondingauthorat:DepartmentofUrology,InstitutoNacionaldeCienciasMédicasyNutriciónSalvadorZubirán,VascodeQuiroga 15,Col.SecciónXVI,Tlalpan14000,México,D.F.,Mexico.Tel.:+525554870900x2145;fax:+525554854380.

E-mailaddress:[email protected](R.A.Castillejos-Molina).

http://dx.doi.org/10.1016/j.uromx.2015.06.009

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PALABRASCLAVE Disfuncióneréctil;

Hombresjóvenes;

Factoresderiesgo

Disfunciónsexualyfactoresderiesgoenpoblacióndeadultosjóvenesmexicanos:

larelevanciadetenerunaparejaestable

Resumen

Objetivo: DeterminarlaprevalenciadeDEysusfactoresasociadosenunapoblacióndehombres mexicanosde18-40a˜nos.

Materialesymétodos:Estudioobservacional,transversal,descriptivoyanalítico.Seutilizóun cuestionariopara la recoleccióndeinformación.Elcuestionarioincluyóel«Urologic Health SurveyforMen»yel«InternationalIndexofErectileFunction5-item».Igualmenteserecabó informaciónsociodemográﬁca,clínicayotrasvariablesdecomportamientosexual.

Resultados: Serespondieron373cuestionariosyúnicamente160estabancompletos,quefueron losutilizadosparaelanálisis.Lamediadeedadfue25.59±5.45a˜nos.LaprevalenciadeDE fuedel33.7%(leve:17.5%,leve-moderada:8.1%,moderada:6.3%ysevera:1.9%).Elpuntaje promediofue24.38±0.94enpacientessin-DEy 15.41±4.81enpacientesconDE.Elanáli- sisunivariadomostródiferenciasentrelosgruposenedad(p<0.01),«tenerparejaestable»

(p<0.01),«dormirconsupareja» (p<0.01),orientaciónsexual(p=0.04)y enelnúmerode relacionessexualesenlaúltimasemana(p<0.01).Elanálisismultivariadosolomostródiferen- ciassigniﬁcativasen«notenerunaparejaestable»comofactorderiesgo(p=0.027,OR=2.60 [IC:1.11-6.08]).

Conclusiones:LaprevalenciadeDEesdel33.7%enmexicanosjóvenes(enlamayoríaesleve).

Tenerunaparejaestableesfavorable.Noseasociaronvariablesorgánicas.

© 2015 Publicado por Masson Doyma México S.A. en nombre de Sociedad Mexi- cana de Urología. Este es un artículo Open Access bajo la licencia CC BY-NC-ND (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Introduction

Erectile dysfunction (ED) prevalence increases with age and severely affectsquality of life.¹ Despite being a fre- quent reason for urologic consultation, it is considered underestimatedbypatients,aswellasunder-diagnosedand under-treated, particularly in young patients. There are approximately20millionyoungadultsinMexico²andED³is increasinglybeingdiagnosedinthisagegroup,yetlittlespe- ciﬁcinformationisavailable.Internationalstudiesreported anED prevalence of30---35%for malesbetween18and 40 yearsofage.^4,5AsurveybyBarroso-Aguirreetal.reported aprevalenceof9.7%inMexicanyoungadults.⁶Severalrisk factorshavebeendescribedforEDsuchasdiabetesmellitus, obesity,smoking,hyperlipidemia,hypertension,lowurinary tractsymptoms,andlowphysicalactivity.^4,7However,given thatyoungadultshavealowerprevalenceofthesetypesof comorbidities,otherriskfactorsmayplayagreaterrole.The aimofthisstudywastodeterminetheprevalenceofEDand itsassociatedriskfactorsamongMexicanadultsbetween18 and40yearsofage.

Methods

Anobservational,cross-sectional,descriptive,andanalytic studywasdesigned.ProperapprovalbyourlocalEthicsCom- mittee wasobtained. Young male volunteers between 18 and40yearsofageansweredtheUrologicalHealthSurvey for Men, together with the International Index of Erec- tile Function (IIEF-5) questionnaire.⁸ The survey included sociodemographic,clinical, andsexualbehavior variables.

Participants from Mexico City were invited by e-mail or

socialnetworkstoanonymously accessasecure website- hosted survey (www.surveymonkey.com/s/ESUMasculina).

Invitations were sent to addresses included in databases fromuniversitiesinMexicoCity.

EDwasgradedusingtheIIEF-5score,accordingtopre- viouslyreportedcriteria. Patientswithascore≥22 points wereconsiderednot tohave ED.³ ED wasclassiﬁedinto4 groups:mild(17---21),mild-to-moderate(12---16),moderate (8---11),andsevere(5---7).⁸UnivariateanalysisusingtheStu- dent’standchi-squaretestswasperformed,andalogistic regressionmultivariateanalysismodelwasusedtocalculate theriskfactorsforED.Statisticalsigniﬁcancewasstatedas p<0.05.AnalysiswasdoneusingtheStatisticalPackagefor SocialSciences,version17.0(SPSSInc.,Chicago,IL,USA).

Results

Atotalof373surveyswereobtained.Onehundredandsixty subjectscompletedtheentirequestionnaireandhadbeen sexuallyactiveinthepreviousmonth,andsowereincluded astheﬁnalsample ofourstudy(Fig.1).The meanageof the participants was 25.6±5.4 years. The prevalence of ED was33.7% (n=54) according tothe IIEF-5(Fig. 2)and thedistributionfor eachseveritygroupwas17.5%(n=28), 8.1%(n=13),6.3%(n=10),and1.9%(n=3)for mild,mild- to-moderate,moderate, andsevere,respectively (Fig.2).

ThemeanIIEF-5scoreforhealthymaleswas24.4±0.9vs.

15.4±4.8intheEDgroup.

Seventy-eightpercentofsubjectsweresingleand21.8%

were married or living with a partner (common law). In termsofeducationallevel,86.9%wereincollegeorhigher and13.1% had only elementary or high school education.

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Total subjects that entered the web page

n=373

Completely missing data

n=62 Total registered

subjects n=311

Evaluable patients n=200

Total sample n=160

Healthy n=106 Erectile dysfunction

n=54 No sexual activity

during previous month

n=30 Partially missing data for analysis

n=111

Figure1 Managementofsurveysforﬁnalanalysis.

Healthy Total erectile dysfunction

Mild Mild to moderate

Moderate Severe 1.90 6.30

8.10 17.50

33.70 67.70

80.00 70.00 60.00 50.00 40.00 30.00 20.00 10.00 0.00

Figure2 EDseveritygroups(%).

Accordingtosexualorientation,80.6%patientswerehetero- sexual,13.8%homosexual,and5.6%bisexual.Onehundred thirty-three(83.1%)patientsinitiatedsexualactivitybefore 20yearsofageandthemeanofprevioussexualpartnerswas

9.9±16.1Condomusehadalwaysbeennullin21.2%ofthe subjectsand15.5%wereunsatisﬁedwiththesize/thickness of their penis. In this group, 28.8% of the subjects were circumcised.

AunivariateanalysiscomparingEDversushealthygroups showed a signiﬁcant difference in age (p<0.01). Patient comorbiditiesrelatedtoEDdiagnosisareshowninTable1, andtherewerenosigniﬁcantdifferences.Nodifferencein educationallevelwasfound.

Table2showsthesexualbehaviorandsexualexperience variables.Havingastablesexualpartner(p<0.001),sleeping withthesexual partner (p<0.001),sexual orientation (p=0.04), and the numberof sexual intercourse episodes perweek(p<0.001)werestatisticallydifferentamongthe groups.

Allsigniﬁcantvariablesfromtheunivariateanalysiswere includedinalogisticregressionmultivariatemodel,which isshowninTable3.Theonlyvariablethatremainedsigniﬁ- cantasariskfactorforEDwas‘‘nothavingastablesexual partner’’(p=0.027,OR=2.60[CI1.11---6.08]).

Discussion

The prevalence of ED in young men and the associated riskfactorshavebeendescribedfor differentpopulations.

Table4showsthereportedprevalenceofEDinourcountry andininternationalstudies.Laumannetal.,oneoftheﬁrst authors to investigate sexual dysfunction, surveyed 1410 men18---59yearsofageintheNationalHealthandSocialLife Survey(NHSLS).Hefounda7%prevalenceofEDinthegroup ofsubjects18---29yearsoldand9%in thegroupof 30---39- year-olds.⁹ Ponholzeretal.,inaserieswith2869patients fromAustria,reportedan ED prevalence of25.5---28.9% in patientsbetween 20and50yearsofage.⁷The evaluation methodmaymodifytheprevalence.¹⁰InapaperbyMartin- Moralesetal., an8.48% prevalence ofED in thegroup of 25---39-year-oldswasfound using6questions(1---5 and15) fromtheIIEF;theprevalencechangedto3.92%whenasingle directquestionwasused.¹¹

Table1 UnivariateanalysisofclinicalanddemographicvariablesrelatedtoErectileDysfunctionDiagnosis.

Variable Unit Total^a

n=160

Erectiledysfunction^a n=54

Healthy^a n=106

pvalue

Age Years 24.8±3.2 24.0±4.2 26.4±5.8 <0.01

Bodymassindex kg/m² 25.6±5.5 24.6±3.2 24.9±10.6 0.63

Variable Reference Total[n(%)]

n=160

Erectile

dysfunction[n(%)]

n=54

Healthy[n(%)]

n=106

pvalue

Diabetesmellitus Yes 0(0) 0(0) 0(0) 0.90

Arterialhypertension Yes 1(0.6) 0(0) 1(0.9) 0.49

Dyslipidemia Yes 2(1.3) 0(0) 2(1.9) 0.33

Exercise Yes 110(68.8) 39(72.2) 71(67.0) 0.43

Depression Yes 6(3.8) 5(9.3) 1(0.9) 0.19

Smoking Yes 42(26.2) 16(29.6) 26(24.5) 0.65

Education College/higher 139(86.9) 47(87.0) 92(86.8) 0.67

Lower 21(13.1) 7(13.0) 14(13.2)

aMean±standarddeviation.

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Table2 UnivariateanalysisofsexualbehaviorandsexualexperiencevariablesrelatedtoErectileDysfunctionDiagnosis.

Variable Unit Total^a

n=160

Erectile dysfunction^a n=54

Healthy^a n=106

pvalue

Totalprevioussexualpartners n 9.9±16.1 7.1±9.1 10.2±16.5 0.12

Sexualpartners(previousmonth) n 1.2±1.2 1.0±0.9 1.3±1.1 0.6

Episodesofsexualintercourse(previousweek) n 1.5±0.9 1.0±0.7 1.9±1.0 <0.01

Variable Reference Total[n(%)]

n=160

Erectile

dysfunction[n(%)]

n=54

Healthy[n(%)]

n=106

pvalue

Circumcision Yes 46(28.8) 11(20.3) 35(33.0) 0.21

Contraception(condom) Never 34(21.2) 12(22.2) 22(20.8) 0.18

Sometimes 51(31.8) 14(25.9) 37(34.9)

Always 75(46.9) 28(51.9) 47(44.3)

PDE5inhibitor Yes 18(11.3) 5(9.3) 13(12.3) 0.76

Drugabuse Yes 5(3.1) 3(5.5) 2(1.9) 0.57

Stablesexualpartner Yes 113(70.6) 26(48.1) 87(82.1) <0.01

Sleepswithsexualpartner Yes 69(43.1) 13(24.1) 56(52.8) <0.01

Maritalstatus Married^b 35(21.8) 8(14.8) 27(25.4) 0.06

Single 125(78.2) 46(85.2) 79(74.6)

Sexualorientation Heterosexual 129(80.6) 35(64.8) 94(88.7) 0.04

Homosexual 22(13.8) 14(25.9) 8(7.5)

Bisexual 9(5.6) 5(9.2) 4(3.8)

Satisfactionwithsize/thicknessofpenis Satisﬁed 135(84.4) 41(75.9) 94(88.7) 0.18

a Mean±standarddeviation.

b Includinglivingwithapartner(commonlaw).

Table3 Logisticmultivariateanalysis:riskfactorsforED.

Variable Reference OR CI(95%) pvalue

Age(years) <30 0.45 0.12---1.67 0.29

Maritalstatus Married/cohabitation 0.52 0.11---2.49 0.41

Sexualorientation Heterosexual 1.61 0.64---4.07 0.30

Stablesexualpartner Nothavingone 2.60 1.11---6.08 0.027

Sexualintercourseperweek Fewerthan3episodes 6.84 0.85---54.89 0.07

Sleepswithpartner Yes 1.83 0.61---5.47 0.27

Table4 ReportederectiledysfunctionprevalenceinyoungadultsinMexicoandtherestoftheworld.

Author Year Country n Age Prevalence(%) EDmeasurement

Barroso-Aguirre¹⁰ 2001 Mexico 1800 18---40 9.7 IIEF

Hernández-Moreno¹⁸ 2004 Mexico 452 18---41 16 IIEF

Actualseries 2013 Mexico 373 18---40 33.8 IIEF

Laumann¹³ 1999 USA 1249 30---39 9 Directquestion

Braun¹⁹ 2000 Germany 4489 30---39 2.3 KEED

Martín-Morales¹⁵ 2001 Spain 2476 25---39 8.48 IIEF

Heruti¹⁶ 2004 Israel 5836 25---55 26.9 SHIM

Ponholzer⁷ 2005 Austria 2869 20---30 25.5---28.9 IIEF

Rynja⁹ 2009 Netherlands 151 17---35 33.6 IIEF

Martins¹⁷ 2010 Brazil 1947 18---40 35 Directquestion

Bayraktar² 2011 Turkey 5438 18---39 1.9 IIEF

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Using a validated questionnaire (IIEF-5, IIEF 1---5+15, SHIM)generallyresultsindiscretediscrepanciesinEDpreva- lenceacrosspopulations.Herutietal.,fromIsrael,founda prevalenceof26.9%fromasampleof5836men25---55years old.¹²Rynjaetal.showedaprevalenceof33.6%inasample of151menaged17---35yearsfromtheNetherlands.⁵Lau- mannetal.reportedaprevalenceof9%inthegroupof30 to39-year-olds.⁹ Martins etal. publisheda study done in Brazil,wherea35%EDprevalencewasreportedinsubjects from18to40yearsofage.¹³

Besides differences among evaluation methods, ED prevalence variations could be explained by the follow- ingfactors:socioculturaldifferences,life-style,education, author biases, selection criteria, statistical analysis, and efﬁciency of health services. We evaluated a particular population sample with speciﬁc characteristics. Our participants came from Mexico City, an almost 100% urban areawithaccesstotheInternet,sopeoplewithamid-high socioeconomicstatusandmid-higheducationallevelwere included.Weacknowledgethislimitation.However,despite beingalimitedsample,itscharacteristicsandbehaviorcan betransferredtoothersimilarpopulations.

Classic papers by Laumann et al. and Ponholzer etal.

described risk factors that have been confirmed by other authors.Theyincludeage,educationalandsocio-economic status,comorbidities,depression,sexualabusehistory,and lowerurinary tract symptoms.^7,9 However,we found that partner availability and previous sexual background were significantfactorsforEDinthispopulation.Ontheonehand, havingastablesexualpartnertosleepwithwasrelatedto normalsexualfunction.Also,havingfewersexualpartners (previousmonth)andfewerepisodesofsexualintercourse (perweek)wasrelatedtoED.Sexualpreferencewasalsoa significantvariable,withagreaterhomosexualandbisexual predilectionintheEDgroup.

Inregardtotherelationbetweensexualpreferenceand sexualdysfunction(SD),therearepreviousreportsinaspe- ciﬁcpopulationofmenthathavesexwithmen(MSM).Two representativestudiesuseditemsfromtheNHSLS,obtain- inga prevalence of 74---79% of subjects withat least one SDsymptom. They found that symptoms, such as perfor- manceanxiety,lowsexualdesire,erectionproblems,orsex notbeingpleasurablewererelatedtoSD.^14,15Ontheother hand,Lauetal.foundthat42.5%ofChineseMSMhadatleast oneSDsymptom (painduringsex,13.8%; prematureejac- ulation,10.4%;anxiety,18.7%;erectileproblems,6.3%;no pleasure,13.8%;noorgasm,5.6%;hypoactivesexualdesire, 8.3%).¹⁶Breyeretal.reportedahigherrateofEDinhomo- sexualmen,comparedwithheterosexualmen(24%vs.12%, respectively,p=0.019).¹⁷

Partneravailabilityemergesasanimportantriskfactorin thisagegroup.Previousreportsdescribing‘‘lackofpartner availability’’asarisk factorfor EDaredescribed inolder adultpopulations.Theymainlyfocusontheimpactofmar- italstatusandpartner’shealthstatus.^18,19Ourresultsshow thathavinganavailablepartnerisalsoimportantinthispar- ticularagegroup.Itmayhaveanimpactonthefrequencyof sexualintercourse,aswellastheexperienceandcomfort gainedwith thepartner. Interestingly, younger age wasa riskfactorforEDinouranalysis.Webelievethatitismainly relatedtostablepartner availability,but it couldalsobe relatedtowhatwe might call ‘‘developedsexual skills’’.

Despitethefactthatwecannotproveacausalrelationship, wefeelthatmorefrequentintercourseandawidervariety ofsexualpartnersmayaidindevelopingamoresatisfactory sexualpractice.

EDhasbeen relatedtoorganicdiseases suchashyper- tensionordiabetesmellitus.Avalidatedcomorbidityindex questionnaire was not included. However, given the low prevalenceofchronicdiseasesinthisagegroup,weconsider itmaynothaveinﬂuencedourglobalresults.

Anotherweaknessofourstudywasthelackofaglobal evaluationofpsychosocialfactors.Sinceonlydepressionwas directlyqueriedandwasnotrecognizedasariskfactor, a complete psychologicalevaluationwouldhave beenideal.

Recentstudiessuggestthatpoormentalhealth,stress,anxiety, or alexithymia may have an impact on ED.^20,21 The method by whichthe surveywas completedprecludes an easyevaluation,butweplantoincludeatleastavalidated questionnaireinfuturestudies.

Finally,avalidatedqualityoflifeanalysiswasnotdone.

Most of the participants had mild ED, but we did not measure its impact. We did not directly evaluate socio- economic status, but the survey was web-hosted, which mayreﬂectarelativelyhigherandeducatedsocioeconomic group.

Conclusions

Inourstudy,youngMexicanadultshadanEDprevalenceof 33.7%andmost ofthecasesweremild (17.5%).Wefound that ayounger age,homosexualorientation, nothaving a stable sexual partner, not sleeping with a partner, and a lowernumberof sexualintercoursesperweek arefactors related to ED in the univariate analysis. The only signiﬁ- cantriskfactorinthemultivariateanalysiswasnothavinga stablesexualpartner.Sexualexperienceandpartneravail- abilityareimportant factorsinﬂuencingEDin youngmale subjects.

Ethical disclosures

Protection of human and animal subjects.The authors declarethatnoexperimentswereperformedonhumansor animalsforthisinvestigation.

Conﬁdentialityofdata.Theauthorsdeclarethatnopatient dataappearsinthisarticle.

Right to privacy and informed consent.The authors declarethatnopatientdataappearsinthisarticle.

Funding

No ﬁnancial support was received in relation to this study/article.

Conﬂict of interest

Theauthorsdeclarethatthereisnoconﬂictofinterest.

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