. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Gender-specific differences in major cardiacevents and mortality in lamin A/C mutationcarriersIngrid A.W. van Rijsingen1, Eline A. Nannenberg2, Eloisa Arbustini3, Perry M. Elliott4,Jens Mogensen5, Johanna F. Hermans-van Ast6, Anneke J. van der Kooi7,J. Peter van Tintelen6,8, Maarten P. van den Berg8, Maurizia Grasso3, Alessandra Serio3,Sharon Jenkins4, Camilla Rowland4, Pascale Richard10, Arthur A.M. Wilde1,Andreas Perrot11, Sabine Pankuweit12, Aeilko H. Zwinderman13, Philippe Charron10,Imke Christiaans2, and Yigal M. Pinto1*

1Department of Cardiology (Heart Failure Research Center), Academic Medical Center, Amsterdam, The Netherlands; 2Department of Clinical Genetics, Academic Medical Center,Amsterdam, The Netherlands; 3Department of Cardiology, Center for Heritable Cardiovascular Diseases, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; 4Departmentof Cardiology, The Heart Hospital, London, UK; 5Department of Cardiology, Aarhus University Hospital, Skejby, Denmark; 6ICIN Netherlands Heart Institute/Durrer Centerfor Cardiogenetic Research, The Netherlands; 7Department of Neurology, Academic Medical Center, Amsterdam, The Netherlands; 8Department of Genetics, University ofGroningen, University Medical Center Groningen, The Netherlands; 9Department of Cardiology, University of Groningen, University Medical Center Groningen, The Netherlands;10Referral Center for Inherited Cardiac Diseases, UPMC Univ Paris 6, AP-HP, Hopital Pitie-Salpetriere, Paris, France; 11Department of Cardiology, Experimental & ClinicalResearch Center, Charite-Universitaetsmedizin, Berlin, Germany; 12Department of Cardiology, University Hospital Marburg, Germany; and; and 13Department of Epidemiology,Academic Medical Center, Amsterdam, The Netherlands

Received 11 July 2012; revised 17 September 2012; accepted 21 September 2012; online publish-ahead-of-print 25 November 2012

Aims Mutations in the lamin A/C gene (LMNA) cause a variety of clinical phenotypes, including dilated cardiomyopathy.LMNA is one of the most prevalent mutated genes in dilated cardiomyopathy, and is associated with a high risk ofarrhythmias, sudden cardiac death, and heart failure. There are few data on the impact of age and gender oncardiac disease penetrance and mortality.

Methodsand results

In a multicentre cohort of 269 LMNA mutation carriers, we evaluated gender-specific penetrance of cardiac involve-ment and major cardiac events. All-cause mortality of mutation carriers [standardized mortality ratio (SMR)] wasdetermined. Cardiac disease penetrance was age dependent and almost complete at the age of 70 years. The pres-ence of an LVEF ≤45% was significantly higher in men (P , 0.001). However, there was no difference betweengenders in the prevalence of atrioventricular block, atrial tachyarrhythmias, and non-sustained ventricular tachycardia.Malignant ventricular arrhythmias (26% vs. 8%) and end-stage heart failure (28% vs. 14%) were more common in menthan in women (P , 0.001 and P ¼ 0.006, respectively). All-cause mortality of mutation carriers was significantlyincreased [SMR 4.0, 95% confidence interval (CI) 2.8–5.2] between the ages of 15 and 75 years. Mortality in menwas higher than in women (hazard ratio 2.2, 95% CI 1.2–4.3).

Conclusions This large cohort of LMNA mutation carriers demonstrates a high cardiac disease penetrance and a high mortality inmutation carriers. Male mutation carriers have a worse prognosis due to a higher prevalence of malignant ventriculararrhythmias and end-stage heart failure.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -Keywords Lamin A/C † Gender † Mortality † Cardiomyopathy † Penetrance

* Corresponding author. Department of Cardiology, AMC, Academic Medical Center Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, PO Box 22660, 1100 DD Amsterdam,The Netherlands. Tel: +31 20 5664927, Fax: +31 20 6976177, Email: y.pinto@amc.uva.nl

Published on behalf of the European Society of Cardiology. All rights reserved. & The Author 2012. For permissions please email: journals.permissions@oup.com.

European Journal of Heart Failure (2013) 15, 376–384doi:10.1093/eurjhf/hfs191

IntroductionNuclear structural proteins lamin A and C are expressed in avariety of terminally differentiated tissues, and mutations in theLMNA gene that encodes lamin A and C can therefore cause avariety of clinical phenotypes, ranging from skeletal and cardiac my-opathies to lipodystrophy and premature ageing.1– 3 Although thecausative mechanism behind these different phenotypes remainsobscure, several functions of lamin A and C have been unrav-elled.4,5 Lamin A and C are important in the maintenance of thenuclear architecture, and play a role in chromatin organizationand gene regulation.4,5

Cardiac manifestations of mutations in LMNA are characterizedby a high frequency of atrial and ventricular arrhythmias, atrioven-tricular (AV) conduction disorders, and structural abnormalitieswith or without skeletal muscle involvement.6,7 It is noteworthythat LMNA is one of the most frequently involved genes indilated cardiomyopathy (DCM), as mutations appear to be respon-sible for up to 8% of the familial cases and up to a third of the casesof DCM with AV conduction disorders.8 –10

Compared with other forms of familial cardiomyopathy, muta-tions in LMNA are responsible for a more aggressive clinicalcourse due to a high rate of malignant ventricular arrhythmiasand end-stage heart failure, and are associated with a highercardiac disease penetrance which is almost complete when carriersage.8,11– 13 Therefore, the identification of an LMNA mutationdenotes important prognostic information. Overlapping withother forms of familial cardiomyopathy, the cardiac disease expres-sion can be highly variable even within single families, and is age de-pendent.8 Furthermore, the cardiac disease expression might bedifferent between men and women.13 As previously reported,men carrying an LMNA mutation do have a higher risk of malignantventricular arrhythmias compared with women.13 However,further knowledge about gender-specific differences in cardiacdisease penetrance and mortality in LMNA mutation carriers islacking. Further knowledge would be of major importance forthe counselling and treatment of LMNA mutation carriers. There-fore, the primary aim of this study was to determine whetherthere are gender-specific differences in cardiac disease penetranceand mortality in LMNA mutation carriers.

Methods

Study settings and designThe data of LMNA mutation carriers (probands and relatives) diag-nosed with a pathogenic LMNA mutation and followed at eightcentres from six European countries were retrospectively collectedas described before (Supplementary material, Table S1a).13 In brief,mutation carriers older than 15 years of age who had been investigatedby a cardiologist at least once were enrolled in this cohort. Individualswith a previously published pathogenic LMNA mutation with cardiac in-volvement and individuals with a newly identified LMNA mutation withclinical or familial evidence of a laminopathy with possible cardiac in-volvement were included.

Clinical information from all documented visits to the cardiologistand medical history were recorded. Data were obtained for allmajor events, including details on cardiovascular events. Because of

the known muscular involvement in LMNA mutation carriers, a major-ity of the patients were referred for neurological examination, but thatwas not standard practice in all patients. The diagnosis of muscular dys-trophy was made by a neurologist based on standard diagnostic criteriafor Emery–Dreifuss muscular dystrophy and for limb girdle musculardystrophy type 1B.14,15

Cardiac involvementCardiac involvement was defined as AV block, atrial tachyarrhythmias,non-sustained ventricular tachycardia (NSVT), and LVEF ≤ 45%.

AV block was classified as first, second, or third degree. First-degreeAV block was defined by a PR interval ≥ 0.20 s.

Atrial tachyarrhythmias were classified as paroxysmal, persistent,permanent AF, and atrial flutter.

Non-sustained ventricular tachycardia on 24 h Holter monitoringwas defined as three or more consecutive ventricular beats with arate of ≥ 120 b.p.m. with a duration of , 30 s.

For the purposes of this study, cardiomyopathy was defined as anLVEF ≤ 45% on echocardiography.16 Dilation of the LV was notincluded in the definition, because LMNA mutation carriers oftenhave less severe LV dilation compared with patients with DCMwithout an LMNA mutation.8

Major eventsThe primary endpoint was a composite of malignant ventriculararrhythmias and end-stage heart failure.

Malignant ventricular arrhythmias were defined as appropriateimplantable cardioverter defibrillator (ICD) treatment, cardiopulmon-ary resuscitation, or sudden cardiac death. Appropriate ICD treatmentwas classified as an ICD discharge for termination of ventricular fibril-lation (VF) or VT, or antitachycardia pacing for termination of sus-tained VT. Sudden cardiac death was defined as witnessed suddencardiac death with or without documented VF, or death within 1 hof acute symptoms, or nocturnal death with no antecedent historyof worsening symptoms. Cardiopulmonary resuscitation was definedas a successful basic life support for a cardiac arrest.

End-stage heart failure was defined as cardiac transplantation ordeath caused by heart failure.

Cardiac disease penetrance was defined by the first presence of AVblock, atrial tachyarrhythmias, NSVT on Holter monitoring, LVEF ≤45%, malignant ventricular arrhythmias, or end-stage heart failure.

Statistical analysisClinical characteristics were compared using the Student’s unpairedt-test for continuous variables, and the Pearson x2 test for categoricalvariables expressed as proportions.

Date of birth was used as the starting point for the time-to-eventanalyses. In mutation carriers without an event, the follow-up periodextended to the most recent evaluation or was censored at last follow-up in March 2010. The log-rank test was used to compare failure–timecurves between subgroups of mutation carriers. The mortality of themutation carriers (observed) was compared with the mortality ofthe Dutch general population (expected) standardized for age,gender, and calendar period as described previously.17 In brief, theratio of observed to expected number of deaths is the standardizedmortality ratio (SMR), and was calculated from the age of 15 yearsuntil death due to all causes or end of follow-up. The 95% confidenceinterval (CI) of the SMR was calculated assuming a Poisson distributionof the observed number of deaths and by using exact limits.

PASW software version 18.0 (SPSS Inc., Chicago, IL, USA) was used.A P-value of ,0.05 was considered statistically significant.

Gender-specific differences in lamin A/C mutation carriers 377

Results

Characteristics and cardiac diseasepenetranceOf the 269 LMNA mutation carriers, 55% were men. Mean age atlast follow-up by the cardiologist was the same for both genders,with a mean age of 42+ 14 years for men and 44+14 yearsfor women (Table 1; Supplementary material, Table S1b). Themedian follow-up from the first visit to the cardiologist until thelast visit was comparable in men [48; interquartile range (IQR)

17–96 months] and women (48; IQR 28–128 months). Anequal number of men and women had cardiac and/or skeletalmuscle manifestations: 85% of the men were affected and 79% ofthe women, P ¼ 0.266. Cardiac disease penetrance was age de-pendent and was almost complete at the age of 70 years(Figure 1). The occurrence of AV block, atrial tachyarrhythmias,and NSVT did not differ between men and women, even after cor-rection for age. However, more men had an LVEF ≤ 45% com-pared with women (66% vs. 37%, P , 0.001), also aftercorrection for age (P ¼ 0.001) (Figure 2 and Table 2).

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 1 Characteristics of 269 LMNA mutation carriers at last follow-up

Characteristics Men (n 5 148) Women (n 5 121) P-value

Age, years 42+14 44+14 0.561

Probands 70/148 (47) 39/121 (32) 0.012

Missense mutations 90/148 (61) 57/121 (47) 0.025

Co-morbiditiesa

Coronary artery diseaseb 4/147 (3) 1/120 (1) 0.258

Hypertension 13/147 (9) 8/121 (7) 0.499

Diabetes mellitus 2/147 (1) 2/120 (2) 0.838

Cardiac and skeletal involvement

AV block 76/139 (55) 61/114 (54) 0.853

Atrial tachyarrhythmias 62/145 (43) 53/119 (45) 0.772

NSVT 70/135 (52) 51/114 (45) 0.263

LVEF ≤45% 92/140 (66) 44/118 (37) ,0.001

LV diameter, mma 57+8 50+6 ,0.001c

Muscular dystrophya 21/117 (18) 20/81 (25) 0.250

Unaffected 22/142 (15) 23/110 (21) 0.266

ICD implantation 71/146 (49) 46/118 (39) 0.117

PM implantationd 16/146 (11) 15/118 (13) 0.660

Medicationa

Beta-blocker 33/145 (23) 17/115 (15) 0.105

ACE inhibitor or ARB 48/145 (33) 18/115 (16) 0.001

Diuretic 38/145 (26) 15/115 (13) 0.009

Calcium channel blocker 3/145 (2) 3/115 (3) 1.000

Major cardiac events

Malignant ventricular arrhythmias 38/148 (26) 10/121 (8) ,0.001

Cardiopulmonary resuscitation 8/144 (6) 3/118 (3) 0.354

Appropriate ICD shock 22/148 (15) 6/121 (5) 0.008

Sudden cardiac death 11/148 (7) 3/121 (2) 0.068

End-stage HF 41/148 (28) 16/121 (13) 0.006

Heart transplantation 24/148 (16) 12/121 (10) 0.131

Death during or after heart transplantation 3/148 (2) 3/121 (3) 0.803

Death due to end-stage heart failure 17/148 (11) 4/121 (3) 0.013

Death due to other causes 1/148(1) 3/121 (3) 0.224

All variables are given as number present/total number (%), except for age and left ventricular diameter, which are given as mean+ SD.AV block, atrioventricular block; HF, heart failure; ICD, implantable cardioverter defibrillator; NSVT, non-sustained ventricular tachycardia on Holter monitoring; PM, pacemaker;Unaffected, number of carriers with am LVEF .45%, absence of arrhythmias, conduction disturbances, and muscular dystrophy.aAt baseline.bDiagnosis coronary artery disease was defined as prior myocardial infarction, revascularization procedure, and/or evidence of coronary artery stenosis of .50%. Coronary arterydisease was excluded based on absence of typical clinical complaints.cP-value not representative, as LV diameters were not corrected for age, height, and weight.31 Based on data of 116 men and 93 women. Cut-off values of LV enlargement aredifferent between men and women: ≥64 mm for men and ≥58 mm for women.32

dPacemaker without an ICD function.

I.A.W. van Rijsingen et al.378

Major cardiac eventsMalignant ventricular arrhythmias were significantly more frequentin men compared with women (26% vs. 8%, P , 0.001) (Table 1).When we analysed the three subgroups of malignant ventriculararrhythmias separately, the frequency of cardiopulmonary resusci-tation and sudden cardiac death was similar. Only the number ofappropriate ICD shocks was significantly higher in men comparedwith in women (15% vs. 5%, P ¼ 0.008).

More men developed end-stage heart failure compared withwomen (28% vs. 13%, P ¼ 0.006). There was no difference inthe number of heart transplantations. The number of men thatdied due to heart failure was higher in men than in women (12%vs. 3%, P ¼ 0.013). (Supplementary material, Table S1c providesan overview of the major cardiac events per country.)

After correction for age, the occurrence of malignant ventriculararrhythmias and end-stage heart failure was higher in men(Figure 2). In half of the men, malignant ventricular arrhythmias oc-curred before the age of 62 years. At the age of 65 years, anepisode of malignant ventricular arrhythmias occurred in 64% ofthe men and in 38% of the women. At an age of 59 years, halfof the men had developed end-stage heart failure. At the age of65 years, 69% of the men and 36% of the women had developedend-stage heart failure (Table 2).

MortalityAt the end of follow-up, 45 (17%) individuals had died at a meanage of 50+ 11 years (range 17–66). Heart failure was the mostprevalent cause of death (47%), followed by sudden cardiac

death (31%), death during or after cardiac transplantation (13%),and other causes of death (9%).

In mutations carriers, the overall SMR (between 15 and 75years) was 4.0 (95% CI 2.8–5.2) in 7614 person-years (Figure 3).In men, 32 deaths occurred, with an overall SMR of 4.4 (95% CI2.9–5.9). Significant excess mortality was observed between 45and 55 years of age (SMR 8.2, 95% CI 4.6–13.5) and between55 and 65 years of age (SMR 5.0, 95% CI 2.2–9.8). In women,13 deaths occurred, with an overall SMR of 3.3 (95% CI 1.5–5.1). Although SMRs were increased from the age of 35, significantexcess mortality was observed between 55 and 65 years (SMR 4.8,95% CI 1.3–12.2). The mortality was higher in men than in women[hazard ratio (HR) 2.2, 95% CI 1.2–4.3].

Possible confoundersFurthermore, differences between men and women wereobserved in the number of probands, missense mutations, and pre-scribed medication. More men were probands compared withwomen (47% vs. 32%, P ¼ 0.012) (Table 1). The penetrance ofcardiac manifestations in relatives was as high as in probands,except for age-dependent penetrance of LVEF ≤ 45% which washigher in probands (Supplementary material, Figure S1a). Afterstratification for gender, there was no difference in LVEF ≤ 45%between male probands and relatives (P ¼ 0.183) but onlybetween female probands and relatives (P ¼ 0.011) (data notshown, available on request).

The prevalence of missense mutations was higher in men (61% vs.47%, P ¼ 0.025). Further analyses showed higher occurrence ofmalignant ventricular arrhythmias in carriers of a non-missensemutation (P ¼ 0.031) (Supplementary material, Figure S1b). Therewas no difference in all-cause mortality and the occurrence of end-stage heart failure between missense and non-missense mutationcarriers (P ¼ 0.109 and P ¼ 0.094, respectively). After stratificationfor gender, the outcome was worse in men carrying a non-missensemutation compared with men carrying a missense mutation.However, in females, these differences were not detectable.

An equal number of beta-blockers and calcium channel blockerswere prescribed at baseline to men and women (23% vs. 15%, P ¼0.105 and 2% vs. 3%, P ¼ 1.000, respectively). However, more menreceived diuretics and ACE inhibitors or ARBs (26% vs. 13%, P ¼0.009 and 33% vs. 16%, P ¼ 0.001, respectively). Furthermore, sig-nificantly more individuals in whom a major cardiac event or deathoccurred received diuretics and an ACE/ARB (Supplementary ma-terial, Table S1d).

DiscussionThis study confirms the high cardiac disease penetrance and highmortality in LMNA mutation carriers and identifies gender-specificdifferences in major cardiac events and mortality. The age of firstcardiac involvement is comparable in men and women. However,the frequency of malignant ventricular arrhythmias and end-stageheart failure is higher in men. Men also have an increased mortalitycompared with women.

Lamin A and C are nuclear matrix proteins located on thenuclear surface of the inner nuclear membrane encoded by thesame gene (LMNA) and are expressed in post-mitotic cells.18 Up

Figure 1 Overview of cardiac disease penetrance in 269 LMNAmutation carriers. Kaplan–Meier event-free survival, stratified bygender. Cardiac disease penetrance is defined by the first pres-ence of atrioventricular block, atrial tachyarrhythmias, non-sustained ventricular tachycardia on Holter monitoring, LVEF≤45%, malignant ventricular arrhythmias, or end-stage heartfailure.

Gender-specific differences in lamin A/C mutation carriers 379

Figure 2 Overview of cardiac disease penetrance in 269 LMNA mutation carriers divided in subgroups of cardiac abnormalities. AV-block,atrioventricular block; NSVT, non-sustained ventricular tachycardia on Holter monitoring.

I.A.W. van Rijsingen et al.380

to a dozen different clinical phenotypes are related to LMNA muta-tions, with a wide spectrum of clinical phenotypes including familialpartial lipodystrophy, premature ageing syndromes, and cardiomy-opathy.5 The exact molecular mechanism is not fully unravelledyet.18 The cardiac phenotype is characterized by an early onsetof AV conduction disorders, supra- and ventricular tachyarrhyth-mias, and later progression to end-stage heart failure.19 Thisstudy provides insight into age- and gender-dependent cardiacdisease penetrance in carriers of cardiac disease-causing LMNAmutations. The first cardiac involvement caused by an LMNA mu-tation is characterized by AV conduction disorders, atrial tachyar-rhythmias, NSVT, and a reduced LVEF. These cardiac abnormalitiesare also described in the general population and are mostly age andgender dependent. However, the prevalence of these cardiac ab-normalities in the general population under the age of 70 yearsis low (,3%).20– 23 With the high prevalence of the cardiac abnor-malities in this cohort of LMNA mutation carriers, it seems reason-able that these cardiac abnormalities are directly related to theLMNA mutation.

This study confirms a high cardiac disease penetrance in LMNAmutation carriers, with a comparable age of onset of conductiondisorders, atrial tachyarrhythmias, and NSVT in men and women.Furthermore, the age-dependent penetrance of a reduced LV func-tion was even higher in men than in women. At the age of 65years, . 90% of the men showed a reduced LV function comparedwith 78% of the women. The diagnosis of DCM is based on thepresence of a reduced LV function, combined with a dilation ofthe left ventricle. In LMNA mutation carriers, the LV dilatation isless prominent than in patients with DCM without an LMNA mu-tation.8 For this reason, the diagnosis cardiomyopathy was in this

study exclusively based on the presence of a reduced LV function,with the consequence that the number of patients that fulfilled thediagnostic criteria for DCM would be lower.

Mutations in LMNA are inherited in an autosomal dominantmanner; therefore, no gender differences should be expecteddue to the inheritance pattern. However, in a previous study, wereported that men have a higher risk of malignant ventriculararrhythmias.13 This study extends these findings by showing thatmen also develop end-stage heart failure more often and have ahigher overall mortality. These gender-specific differences inmajor cardiac events are comparable with the finding of Arimuraet al. in the H222P-LMNA mouse model.24 Gender-specific differ-ences in the development of malignant ventricular arrhythmiasand end-stage heart failure are well known in many idiopathic con-ditions, but have not been extensively documented for LMNAmutations.25,26 One might speculate about possible explanationsfor the differences in major cardiac events between men andwomen; for instance, influences of the sex hormones and suscep-tibility to myocarditis.27,28 Furthermore, cardiac disease progres-sion and outcome might be influenced by environmentalmodifiers and differences in lifestyle.

It has been proposed that non-missense mutations, ins-del/truncating, or mutations affecting splicing could induce haploinsuffi-ciency and thereby causing a more severe phenotype.29 Remarkably,the differences in major cardiac events between the different typesof mutations were detectable in men and not in women. The reasonfor this finding is not obvious; it might be not detectable in womendue to the observed lower cardiac event rate.

To gain insight into the natural history of inherited cardiac dis-eases, data from large and unselected multicentre cohort studieswith both probands and relatives are required.30 Data from bothprobands and relatives are preferred, due to the possible overesti-mation of the cardiac disease penetrance and outcome when onlyprobands are included in a study. In this study, both probands andrelatives were included. Remarkably, in additional analyses, we didnot find major differences in cardiac disease penetrance and majorcardiac events between probands and relatives. Our finding mightbe explained by the high cardiac disease penetrance and the highnumber of major cardiac events in LMNA mutation carriers. Thisobservation made it less likely that the finding that male mutationcarriers were more severely affected was a result of a highernumber of male probands itself. The prescription of medicationat baseline was different between men and women, probably asa consequence of more severe cardiac abnormalities in men. Thetype of study design is not suitable to analyse whether male muta-tion carriers received medication more easily and to investigate theinfluence of the cardiac medication on the progression of thecardiac abnormalities and mortality.

In this analysis, both men and women had an increased mortalitybetween the ages of 15 and 75 years, with a mean SMR of 4.0. Ourresults are in line with the results of earlier studies, whichdescribed an increased mortality in LMNA mutation carriers com-pared with idiopathic DCM patients.8,11

There are limitations to this study that need to be taken intoaccount. Most importantly, the cohort consisted of mutation car-riers from eight academic referral centres, which may have resultedin a referral bias towards more severely affected individuals. This

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Table 2 Cardiac disease penetrance of 269 LMNAmutation carriers

Characteristics Men(n 5 148)

Women(n 5 121)

Age (years) at which 50% of the mutationcarriers are affected

AV block 45 48

Atrial tachyarrhythmias 51 50

NSVT 47 51

LVEF ≤45% 45 55

Malignant ventricular arrhythmias 62 –

End-stage heart failure 59 –

Percentage of affected mutation carriers atage of 65 years

AV block 86% 90%

Atrial tachyarrhythmias 87% 82%

NSVT 82% 82%

LVEF ≤45% 92% 78%

Malignant ventricular arrhythmias 64% 38%

End-stage heart failure 69% 36%

AV block, atrioventricular block; NSVT, non-sustained ventricular tachycardia onHolter monitoring.

Gender-specific differences in lamin A/C mutation carriers 381

effect will be modest, however, because we included both pro-bands and relatives. Furthermore, additional analyses showedthat there were no major differences in cardiac involvementbetween probands and relatives, which is probably explainableby the high penetrance of cardiac disease. Due to the retrospectivedesign of the study, it is possible that there is a selection bias. Aspatients were treated in accordance with local practice, it isreadily conceivable that there were differences in diagnostic,follow-up, and treatment strategies between centres. These differ-ences could have influenced the cardiac disease penetrance andgender-specific differences. The frequency of the malignant ven-tricular arrhythmias might be overestimated, because not all thecardiopulmonary resuscitations and sudden cardiac deaths werewell documented. For the calculation of the SMR, we used dataof the mortality in the Dutch population (available at ‘StatisticsNetherlands’) and compared this with the observed mortality ofthe LMNA mutation carriers despite the fact that not all mutationcarriers were of Dutch origin. However, the difference betweenthe mortality of the normal population in the involved European

countries is low and the influence on the SMR is small (Supplemen-tary material, Table S2).

Clinical implicationsThe high penetrance of cardiac involvement and major cardiacevents found in this study is in line with previous smallerstudies.8,11,12 This underlines the importance of genetic testing inboth probands and relatives, as identification of an LMNA mutationhas an important prognostic value. Besides, it also might guide clin-ical follow-up and therapy. Additionally, the results suggest thatmutation carriers may develop their first cardiac disease manifesta-tions at any age, even at more advanced ages. The implication isthat lifelong follow-up (to at least the age of 75 years) should beconsidered in asymptomatic mutation carriers.

Regular clinical follow-up is indicated in both men and women.The differences in major cardiac events and mortality betweenmen and women suggest more intensive clinical follow-up inmen. The high number of major cardiac events and the high

Figure 3 Survival in 269 LMNA mutation carriers compared with expected survival. CI, confidence interval; SMR, standardized mortality ratio.

I.A.W. van Rijsingen et al.382

mortality identified in this study further support the need forbetter medical therapy strategies for LMNA mutation carriers.

ConclusionThis large cohort of LMNA mutation carriers confirms a highcardiac disease penetrance and mortality in mutation carriers. Fur-thermore, our study demonstrates that men have a worse progno-sis due to a high prevalence of malignant ventricular arrhythmiasand end-stage heart failure despite a similar age of onset.

Supplementary materialSupplementary material is available at European Journal of HeartFailure online.

AcknowledgementsWe are grateful for the assistance of Anna Liew, San Matteo Pavia,Italy, Jan D.H. Jongbloed, University Medical Center Groningen,The Netherlands, and Nynke Hofman and Ronald H. Lekanne ditDeprez, Academic Medical Center, Amsterdam, The Netherlands.We are also grateful for the facilitation of the ‘GENCOR-cardiogenetic database’ of the ICIN Netherlands Heart Institute.

FundingThe Netherlands Foundation for Cardiovascular Excellence (to I.V.R.and Y.P.); the National Ministry of Health and IRCCS Policlinico SanMatteo, Ricerche Correnti, 2006-9, Italy (to E.A.); Inheritance, grantno. EU291924 (to E.A.); the Department of Health’s National Institutefor Health Research (NIHR) Biomedical Research Centres fundingscheme (to UCLH/UCL).

Conflict of interest: none declared.

References1. Muchir A, Bonne G, van der Kooi AJ, van Meegen M, Baas F, Bolhuis PA, de

Visser M, Schwartz K. Identification of mutations in the gene encoding laminsA/C in autosomal dominant limb girdle muscular dystrophy with atrioventricularconduction disturbances (LGMD1B). Hum Mol Genet 2000;9:1453–1459.

2. Flier JS. Pushing the envelope on lipodystrophy. Nat Genet 2000;24:103–104.3. Sylvius N, Tesson F. Lamin A/C and cardiac diseases. Curr Opin Cardiol 2006;21:

159–165.4. Scharner J, Gnocchi VF, Ellis JA, Zammit PS. Genotype–phenotype correlations in

laminopathies: how does fate translate? Biochem Soc Trans 2010;38:257–262.5. Rankin J, Ellard S. The laminopathies: a clinical review. Clin Genet 2006;70:

261–274.6. Fatkin D, MacRae C, Sasaki T, Wolff MR, Porcu M, Frenneaux M, Atherton J,

Vidaillet HJ Jr, Spudich S, De Girolami U, Seidman JG, Seidman C, Muntoni F,Muehle G, Johnson W, McDonough B. Missense mutations in the rod domainof the lamin A/C gene as causes of dilated cardiomyopathy and conduction-system disease. N Engl J Med 1999;341:1715–1724.

7. Brodsky GL, Muntoni F, Miocic S, Sinagra G, Sewry C, Mestroni L. Lamin A/Cgene mutation associated with dilated cardiomyopathy with variable skeletalmuscle involvement. Circulation 2000;101:473–476.

8. Taylor MR, Fain PR, Sinagra G, Robinson ML, Robertson AD, Carniel E, DiLenarda A, Bohlmeyer TJ, Ferguson DA, Brodsky GL, Boucek MM, Lascor J,Moss AC, Li WL, Stetler GL, Muntoni F, Bristow MR, Mestroni L. Naturalhistory of dilated cardiomyopathy due to lamin A/C gene mutations. J Am CollCardiol 2003;41:771–780.

9. Parks SB, Kushner JD, Nauman D, Burgess D, Ludwigsen S, Peterson A, Li D,Jakobs P, Litt M, Porter CB, Rahko PS, Hershberger RE. Lamin A/C mutation ana-lysis in a cohort of 324 unrelated patients with idiopathic or familial dilated car-diomyopathy. Am Heart J 2008;156:161–169.

10. Arbustini E, Pilotto A, Repetto A, Grasso M, Negri A, Diegoli M, Campana C,Scelsi L, Baldini E, Gavazzi A, Tavazzi L. Autosomal dominant dilated cardiomyop-athy with atrioventricular block: a lamin A/C defect-related disease. J Am CollCardiol 2002;39:981–990.

11. Karkkainen S, Helio T, Miettinen R, Tuomainen P, Peltola P, Rummukainen J,Ylitalo K, Kaartinen M, Kuusisto J, Toivonen L, Nieminen MS, Laakso M,Peuhkurinen K. A novel mutation, Ser143Pro, in the lamin A/C gene iscommon in Finnish patients with familial dilated cardiomyopathy. Eur Heart J2004;25:885–893.

12. Pasotti M, Klersy C, Pilotto A, Marziliano N, Rapezzi C, Serio A, Mannarino S,Gambarin F, Favalli V, Grasso M, Agozzino M, Campana C, Gavazzi A, Febo O,Marini M, Landolina M, Mortara A, Piccolo G, Vigano M, Tavazzi L, Arbustini E.Long-term outcome and risk stratification in dilated cardiolaminopathies. J AmColl Cardiol 2008;52:1250–1260.

13. van Rijsingen IA, Arbustini E, Elliott PM, Mogensen J, Hermans-van Ast JF, van derKooi AJ, van Tintelen JP, van den Berg MP, Pilotto A, Pasotti M, Jenkins S,Rowland C, Aslam U, Wilde AA, Perrot A, Pankuweit S, Zwinderman AH,Charron P, Pinto YM. Risk factors for malignant ventricular arrhythmias inlamin a/c mutation carriers: a European cohort study. J Am Coll Cardiol 2012;59:493–500.

14. Norwood F, de Visser M, Eymard B, Lochmuller H, Bushby K. EFNS guideline ondiagnosis and management of limb girdle muscular dystrophies. Eur J Neurol 2007;14:1305–1312.

15. Wehnert M, Muntoni F. 60th ENMC International Workshop: non X-linkedEmery–Dreifuss Muscular Dystrophy 5–7 June 1998, Naarden, The Netherlands.Neuromuscul Disord 1999;9:115–121.

16. Mestroni L, Maisch B, McKenna WJ, Schwartz K, Charron P, Rocco C, Tesson F,Richter A, Wilke A, Komajda M. Guidelines for the study of familial dilated cardio-myopathies. Collaborative Research Group of the European Human and CapitalMobility Project on Familial Dilated Cardiomyopathy. Eur Heart J 1999;20:93–102.

17. Nannenberg EA, Michels M, Christiaans I, Majoor-Krakauer D,Hoedemaekers YM, van Tintelen JP, Lombardi MP, Ten Cate FJ, Schinkel AF,Tijssen JG, van Langen IM, Wilde AA, Sijbrands EJ. Mortality risk of untreatedmyosin-binding protein C-related hypertrophic cardiomyopathy insight into thenatural history. J Am Coll Cardiol 2011;58:2406–2414.

18. Maraldi NM, Capanni C, Cenni V, Fini M, Lattanzi G. Laminopathies andlamin-associated signaling pathways. J Cell Biochem 2011;112:979–992.

19. van Berlo JH, de Voogt WG, van der Kooi AJ, van Tintelen JP, Bonne G, Yaou RB,Duboc D, Rossenbacker T, Heidbuchel H, de Visser M, Crijns HJ, Pinto YM.Meta-analysis of clinical characteristics of 299 carriers of LMNA gene mutations:do lamin A/C mutations portend a high risk of sudden death? J Mol Med 2005;83:79–83.

20. Cheng S, Keyes MJ, Larson MG, McCabe EL, Newton-Cheh C, Levy D,Benjamin EJ, Vasan RS, Wang TJ. Long-term outcomes in individuals with pro-longed PR interval or first-degree atrioventricular block. JAMA 2009;301:2571–2577.

21. Go AS, Hylek EM, Phillips KA, Chang Y, Henault LE, Selby JV, Singer DE. Preva-lence of diagnosed atrial fibrillation in adults: national implications for rhythmmanagement and stroke prevention: the AnTicoagulation and Risk Factors inAtrial Fibrillation (ATRIA) Study. JAMA 2001;285:2370–2375.

22. Bikkina M, Larson MG, Levy D. Prognostic implications of asymptomatic ventricu-lar arrhythmias: the Framingham Heart Study. Ann Intern Med 1992;117:990–996.

23. Schunkert H, Broeckel U, Hense HW, Keil U, Riegger GA. Left-ventricular dys-function. Lancet 1998;351:372.

24. Arimura T, Helbling-Leclerc A, Massart C, Varnous S, Niel F, Lacene E, Fromes Y,Toussaint M, Mura AM, Keller DI, Amthor H, Isnard R, Malissen M, Schwartz K,Bonne G. Mouse model carrying H222P-Lmna mutation develops muscular dys-trophy and dilated cardiomyopathy similar to human striated muscle laminopa-thies. Hum Mol Genet 2005;14:155–169.

25. Santangeli P, di Biase L, Pelargonio G, Natale A. Outcome of invasive electro-physiological procedures and gender: are males and females the same?J Cardiovasc Electrophysiol 2010;22:605–612.

26. Frazier CG, Alexander KP, Newby LK, Anderson S, Iverson E, Packer M, Cohn J,Goldstein S, Douglas PS. Associations of gender and etiology with outcomes inheart failure with systolic dysfunction: a pooled analysis of 5 randomizedcontrol trials. J Am Coll Cardiol 2007;49:1450–1458.

27. Du XJ. Gender modulates cardiac phenotype development in genetically modifiedmice. Cardiovasc Res 2004;63:510–519.

28. Cocker MS, Abdel-Aty H, Strohm O, Friedrich MG. Age and gender effects on theextent of myocardial involvement in acute myocarditis: a cardiovascular magneticresonance study. Heart 2009;95:1925–1930.

29. Wolf CM, Wang L, Alcalai R, Pizard A, Burgon PG, Ahmad F, Sherwood M,Branco DM, Wakimoto H, Fishman GI, See V, Stewart CL, Conner DA,Berul CI, Seidman CE, Seidman JG. Lamin A/C haploinsufficiency causes dilated

Gender-specific differences in lamin A/C mutation carriers 383

cardiomyopathy and apoptosis-triggered cardiac conduction system disease. J MolCell Cardiol 2008;44:293–303.

30. Sen-Chowdhry S, Syrris P, Ward D, Asimaki A, Sevdalis E, McKenna WJ. Clinicaland genetic characterization of families with arrhythmogenic right ventricular dys-plasia/cardiomyopathy provides novel insights into patterns of disease expression.Circulation 2007;115:1710–1720.

31. Henry WL, Gardin JM, Ware JH. Echocardiographic measurements in normal sub-jects from infancy to old age. Circulation 1980;62:1054–1061.

32. Lang RM, Bierig M, Devereux RB, Flachskampf FA, Foster E, Pellikka PA,Picard MH, Roman MJ, Seward J, Shanewise J, Solomon S, Spencer KT, St JohnSutton M, Stewart W. Recommendations for chamber quantification. Eur J Echo-cardiogr 2006;7:79–108.

I.A.W. van Rijsingen et al.384