IJMed Genet 1996;33:737-743

Prediction of psychological functioning one yearafter the predictive test for Huntington's diseaseand impact of the test result on reproductivedecision making

Marleen Decruyenaere, Gerry Evers-Kiebooms, Andrea Boogaerts, Jean-JacquesCassiman, Trees Cloostermans, Koen Demyttenaere, Rene Dom, Jean-Pierre Fryns,Herman Van den Berghe

AbstractFor people at risk for Huntington's dis-ease, the anxiety and uncertainty aboutthe future may be very burdensome andmay be an obstacle to personal decisionmaking about important life issues, forexample, procreation. For some at riskpersons, this situation is the reason forrequesting predictive DNA testing. Theaim of this paper is two-fold. First, wewant to evaluate whether knowing one'scarrier status reduces anxiety and uncer-tainty and whether it facilitates decisionmaking about procreation. Second, weendeavour to identify pretest predictors ofpsychological adaptation one year afterthe predictive test (psychometric evalua-tion of general anxiety, depression level,and ego strength).The impact of the predictive test resultwas assessed in 53 subjects tested, usingpre- and post-test psychometric measure-ment and self-report data of follow upinterviews.Mean anxiety and depression levels weresignificantly decreased one year after agood test result; there was no significantchange in the case ofa bad test result. Themean personality profile, including egostrength, remained unchanged one yearafter the test. The study further shows thatthe test result had a definite impact onreproductive decision making.Stepwise multiple regression analyseswere used to select the best predictors ofthe subject's post-test reactions. The re-sults indicate that a careful evaluation ofpretest ego strength, depression level, andcoping strategies may be helpful in pre-dicting post-test reactions, independentlyof the carrier status. Test result (carrier/non-carrier), gender, and age did not sig-nificantly contribute to the prediction.About one third of the variance of post-test anxiety and depression level and morethan half of the variance of ego strengthwas explained, implying that other psy-chological or social aspects should also betaken into account when predicting indi-vidual post-test reactions.(3 Med Genet 1996;33:737-743)

Key words: Huntington's disease; predictive testing;psychology.

Huntington's disease (HD) is a neurodegen-erative disease, characterised by involuntarymovements (chorea), progressive dementia,and affective disturbances (for example, ag-gression, paranoia). This is caused by aselective and progressive neuronal degenera-tion in the basal ganglia and cerebral cortex.'The age at onset is about 35 to 50 years. HD isinherited as an autosomal dominant trait, withthe HD gene localised on the short arm ofchromosome 4. The 50% risk of getting HDmay be very stressful and may influencedecisions concerning education, marriage,child bearing, and career. Predictive DNA test-ing for Huntington's disease has been availableas a clinical service since 1987, initially byDNA linkage and since mid-1993 by directmutation analysis.`4 In the Centre for HumanGenetics in Leuven, predictive test requests areapproached multidisciplinarily by a team con-sisting of a genetic counsellor, a psychologist, apsychiatrist, a neurologist, and a social worker.During the counselling sessions, full infor-mation is provided on HD and on thepredictive test. The role and psychologicalmeaning of the disease and the test in the life ofthose tested are explored. After the disclosureof the predictive test result, short and longterm emotional and social support are pro-vided. A full description of the approach hasbeen reported by Evers-Kiebooms5 and De-cruyenaere et al.6

Subjects tested seem to be self-selected andmentally resourceful."' Kessler"' hypothesisedthat Barron's psychological construct "egostrength"'2 differentiates between test partici-pants and non-participants. Pretest psycho-metric testing6 showed that many psychologicalcharacteristics did not differ from those of thegeneral population: most test applicants had anormal psychological profile and anxiety anddepression levels were not significantly differ-ent from those of the general population.Those tested were, however, significantly moresocially extroverted and had a significantlyhigher ego strength than the general popula-tion. They also had more positive copingstrategies: active coping, palliative reactions,social support seeking, and comforting ideas.Some authors" '3 '4 have raised the question

ofhow the group ofpeople who have had directtesting might differ from those who have hadlinkage testing, not only with regard to theirfamily interactions and resourcefulness, but

Centre for HumanGenetics, UZGasthuisberg,University of Leuven,Herestraat 49, B-3000Leuven, BelgiumM DecruyenaereG Evers-KieboomsA BoogaertsJ-J CassimanT CloostermansJ-P FrynsH Van den Berghe

Departnent ofPsychiatry, Universityof Leuven, B-3000Leuven, BelgiumK Demyttenaere

Department ofNeurology, Universityof Leuven, B-3000Leuven, BelgiumR Dom

Correspondence to:Professor Evers-Kiebooms.

Received 19 January 1996Revised version accepted forpublication 16 May 1996

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also with regard to their psychological func-tioning after a test result, but this has not beentested in previously published studies.

Studies on the psychological impact of thepredictive test result have reported, in general,a low rate of psychiatric reactions.9 15-20 Com-mon sense might expect positive effects of agood result and negative effects of a bad result.The test outcome has, however, a mixture ofpositive and negative consequences, which mayvary over time. For instance, Bloch et al'6 andHuggins et al'7 found that symptoms of depres-sion and anxiety were most common in carriersin the first two months, but after one year thedepression levels have fallen back to thebaseline level. They became more centred inthe present and had greater difficulty inplanning for the future. While most personsreceiving a decreased risk for HD had fewerdepressive symptoms, approximately 10%needed additional counselling. The most vul-nerable time was between two and 12 monthsafter the test. In particular, those who receiveda test result contradictory to the consciously orunconsciously expected outcome had difficultyin adjusting to the test result. Wiggins et al,9using the General Severity Index from theSymptom Checklist,2' the Beck DepressionInventory," and the General Well-BeingScale,23 concluded that knowing one's carrierstatus reduced uncertainty and provided anopportunity for appropriate planning. Codoriet al'0 observed that the majority of personstested felt relief from uncertainty. A negativeeffect in carriers was psychological burden(worry, guilt). Nevertheless, they focused moreon what they had gained and on their strategiesfor coping with the bad news than on theadverse effects, which was considered as anadaptive response to overwhelming knowledge.One of the conclusions of the research of Tib-ben et al'4 was that, six months after the test,carriers reacted with denial or minimisation ofthe impact of the test outcome; most of themrated their current life situation as being verygood. The test result did not increase the pre-viously expected control over their future.Another observation was that some non-carriers had to adjust to the sudden removal ofthe Huntington scenario: they reacted withabsence of relief and emotional numbness.Effects of predictive testing on the partnerrelationship have been discussed by Demytte-naere et al'5 and Quaid and Wesson.'0The aim of the present paper is two-fold.

First, we wished to evaluate the impact of thepredictive test on the psychological conditionof people tested, using psychometric tests(general anxiety, depression level, and person-ality profile, including ego strength), and ontheir reproductive decisions, one year after thetest. Reduction of uncertainty and family plan-ning decisions proved to be important motivesfor requesting the test.6 We question whetherknowing one's carrier status indeed reducesuncertainty and anxiety and whether it facili-tates reproductive decision making. Second,the paper endeavours to identify predictors ofpsychological adaptation (psychometric evalu-ation of general anxiety, depression level, and

ego strength) one year after the predictive test.The candidate predictive variables consisted ofthe tested subjects' pretest psychological char-acteristics, gender, age, and test result. Untilnow, there have been no published studiesabout the prediction of psychological adapta-tion one year after HD testing by means ofpsychometric tests. The findings may help thecounsellor to an early detection of those at riskfor post-test anxiety or depressive symptoms.

Material and methodsSUBJECTSThe target group of the study consisted of peo-ple tested who received a predictive test resultin a genetic centre in Flanders before April1994 (n=57). During pretest counselling, testapplicants were informed about the set up of alongitudinal study concerning the impact ofthe predictive test on people's life. They allagreed that their psychometric tests and inter-view data could also be used for research pur-poses. For 53 of them complete follow up datawere available: 31 with a favourable and 22with an unfavourable result. The drop outswere two carriers and two non-carriers whowere not interested in follow up counsellingone year after the test. For 34 persons, the testresult was obtained by linkage analysis. Imme-diately after the identification of the gene theywere informed by letter about the possibility ofdirect testing; three of them (two carriers andone non-carrier) asked for a confirmation ofthe initial result. This may be explained by thefact that in our centre indirect testing was onlyperformed after a preceding DNA analysis inthe family had shown that a high level ofinformativity could be expected. Otherwise,those tested did not proceed in the testprogramme and no blood sample was taken foranalysis. Moreover the age adjusted risk aftertesting was very close to 99% or 1% except in afew cases. In the latter, much more attentionwas given to the nature of the risk modificationafter the disclosure of the test result. All testapplicants were very well informed about thesmall level of residual uncertainty, but theysubjectively evaluated their result in a binaryway "carrier" or "non-carrier".

Table 1 presents some of the socio-demographic data. The mean age of the carri-ers is 33.9 years (range 24-50) and of the non-carriers 34.1 years (range 22-76); thedifference is not significant (two tailed t test).The direct testing group did not differsignificantly from the linkage group in thesesociodemographic variables (chi-square andKolmogorov-Smirnov test for independentsamples26 and two tailed t test).French or German speaking subects tested

(n=3) were excluded from the psychometricanalyses since no appropriate tests or normswere available. The statistical analyses wereperformed on the group with a 50% prior risk.The group with a 25% risk was too small (n=4)to analyse.

METHODSTo assess pre- and post-test psychologicalcharacteristics, the following psychometric

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questionnaires were administered during pre-test and follow up counselling. The STAI(State Trait Anxiety Inventory27) contains twoscales: general anxiety (STAI trait) and situ-ational anxiety (STAI state or, in the context ofthis study, anxiety during the counsellingsessions). The BDI (Beck Depression Inven-tory28) assesses the depression level of a person.Situational anxiety (STAI state) and BDI wereadministered in the pretest period as well asone month and one year after the predictivetest. General anxiety (STAI trait) was adminis-tered in the pretest period and one year afterthe test.The MMPI (Minnesota Multiphasic Per-

sonality Inventory29 30) was used to assess gen-eral personality in the pretest period and oneyear after the test. We used the standard scales(see Results section, table 2) and one supple-mentary scale, ego strength or general capacityfor personality integration, developed by Bar-ron.'2 The MMPI scores are represented as Tscores (mean 50, SD 10); they are corrected inorder to limit the effect of defensive responding(K correction29). Norms for a Dutch transla-tion of the MMPI have been calculated on acombined Dutch and Flemish sample.

Last, but not least, the UCL (UtrechtseCoping Lijst3'), a Dutch adaptation of theWestbrook Coping Scale,32 was administered inthe pretest period to evaluate coping strategies:active coping, palliative coping, avoiding reac-tions, social support seeking, depressive-regressive coping, expression of emotions oranger, and comforting ideas.

Table I Sociodemographic characteristics of the peoplewho received a predictive test result more than one year ago

Non-carrier Carrier(n=31) (n=22)

GenderMale 10 12Female 21 10

Marital status and family sizeUnmarried 7 3Married, no children 9 9Married, children 15 10

Desire for children (pretest period)Yes 15 12Undecided 2 1No 14 9

Education< High school 4 0High school 15 12> High school 12 10

Table 2 Mean scores for pre- and post-test state and trait anxiety (STAI),for depression(BDI), andfor Barron's ego strength scale of carriers (n=22) and non-carriers (n=24)

One month later One year later (meanPretest (mean (SD)) (mean (SD)) (SD))

CarriersSTAI state 34.9 (8.5) 34.5 (11.3) 32.7 (8.8)STAItrait 34.1 (6.9) 33.7 (10.1)BDI 3.6 (4.2) 3.4 (4.5) 2.3 (2.5)Ego strength 60.5 (7.2) 60.8 (7.7)

Non-carriersSTAI state 37.1 (8.1) 32.8* (8.3) 31.4t (7.6)STAI trait 38.4 (10.8) 34.2* (7.9)BDI 6.2 (8.7) 2.6t (4.0) 2.5* (3.1)Ego strength 56.0 (13.0) 57.7 (14.0)

* The difference between the pre- and post-test mean is significantly different from zero, withalpha = 0.05.t The difference between the pre- and post-test mean is significantly different from zero, withalpha = 0.01.

Data on reproductive decisions were gath-ered during the counselling session one yearafter the test.

ResultsANXIETY, DEPRESSION LEVEL, AND GENERALPERSONALITY PROFILE, INCLUDING EGOSTRENGTH, ONE YEAR AFTER THE TESTThe mean scores for state and trait anxiety(STAI), for depression (BDI), and for Barron'sego strength (MMPI) in the follow up period,as well as in the pretest period, are presented intable 2. For the non-carriers, the mean for situ-ational anxiety (STAI state), general anxiety(STAI trait), and depression level (BDI) wassignificantly decreased one month and oneyear after the test result (two tailed t tests).Their mean scores on the MMPI standardclinical scales (not in the table) and onBarron's ego strength scale were not signifi-cantly changed. For the carriers, there were nosignificant differences at all between the pre-and the post-test period.The differences between carriers and non-

carriers were not significant, in either thepretest period or the post-test period. Moreo-ver the linkage and the direct testing groupsdid not significantly differ from each other withregard to pre- and post-test psychologicalcharacteristics.

Individual psychometric scores were used toidentify the test applicants with at least a milddepression level (BDI >10) or a high score foranxiety (STAI trait >decile 8), or both, oneyear after the test. Table 3 presents an overviewof the test result and some pre- and post-testscores of the five selected subjects. The firstperson is an unmarried woman (31 years) wholived with her father and had had some failedrelationships. She had a history of asthmaattacks since she was informed of her 50% risk(about 15 years ago). After the test, the symp-toms of asthma had increased. She also hadrelationship problems with her father at thattime. The second subject is a married woman(38 years) with three children. Her life wasseverely marked by the divorce of her parentsduring childhood, the rift with her affectedfather, anxiety about getting the disease, andguilt feelings towards her children. After thetest, she felt better, but she still had a lot ofanxieties and psychosomatic complaints. Sub-ject 3 is a woman (28 years, no children) whohad an immature relationship with her hus-band. One year after getting a good test result,she complained of back pain, headache, andfatigue. She became extremely involved inhelping her parents and others at risk for HD;this may be a reaction to unconscious survivorguilt. Subject 4 is a man (30 years), unmarried,but having a stable relationship for two years.One year after the test the relationship brokeup. This was not unexpected; during thepretest period they claimed that they did notknow whether their relationship would survivea positive test result. The last person is a mar-ried man (38 years) who reported vaguesomatic complaints but no manifest high anxi-ety. After receiving the bad news, he was

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Table 3 Scores offive subjects with mild depression level or high anxiety or both one year after the test

Pretest STAI Post-test Pretest ego Post-test egoResult Pretest BDI Post-test BDI trait STAI trait strength strength

Non-carrier 7 12 40 46 56 48Non-carrier 16 6 53 51 29 37Non-carrier 11 6 47 50 51 43Carrier 8 4 29 49 64 64Carrier 1 4 40 52 59 46

preoccupied by symptom seeking, by fear offailure at work, and of becoming aggressivetowards his wife and children in the future.

REPRODUCTIVE DECISIONS ONE YEAR AFTER THETESTCarriersOne year after testing, four of the 13 coupleswho had considered procreation before the testhad chosen to refrain from (further) reproduc-tion; this was in line with their pretest choiceshould they prove to be a gene carrier. Two ofthese couples had no children yet, the othercouples had two and three children, respec-

tively. Four couples had a pregnancy with pre-

natal diagnosis for HD or were pregnant andplanned a prenatal test. Before testing, three ofthem had planned to have children with prena-

tal diagnosis in the case ofbeing a carrier, whilethe other couple was undecided about repro-

duction at that time. These four couples hadno children when starting the test. One year

after the test, five carriers were undecided withregard to reproduction. The pretest anticipa-tion in the case of being a carrier of these fivesubjects was: giving up reproduction (two per-sons; no children yet in the pretest period),sterilisation (one person; already had one

child), and undecided (two persons; no chil-dren yet).

Non-carriersOne year after receiving a good test result, fivenon-carrier couples had a newborn baby andthree couples were pregnant (five of these eightcouples already had children before the test).One of these eight couples had a prenatal testbecause of advanced maternal age. Anotherwoman was already pregnant before she

received her test result. This couple hadstopped contraception some months before thecommunication of the test result, but they didnot plan a pregnancy until they knew the testoutcome. Had the woman proven to be a gene

carrier, they would not have terminated thepregnancy. One couple had a spontaneous

miscarriage because of a fetal chromosomalanomaly. Three married and two single testapplicants said that they planned to havechildren in the future. One of the above 14persons was undecided about reproductionbefore the test; the others had planned to havechildren in the case of a good test result. Onecouple decided after the test to have no

children; before the test they were undecided(they had a history of subfertility). In two per-

sons who were undecided about reproductionin the pretest period, the indecision persisted.

PREDICTION OF POST-TEST ANXIETY, DEPRESSION,AND EGO STRENGTHIn order to select the best predictors ofindividual post-test general anxiety, depressionlevel, and ego strength, we performed stepwisemultiple regression analyses. Regression analy-sis is the analysis of the relationship betweenone variable and another set of variables,taking into account the correlation betweenthis set of variables. The Pearson correlationsbetween the pretest psychometric measures

(predictor variables) and the post-test criterionvariables are presented in table 4. Predictivetest result, gender, and age did not correlatesignificantly with the post-test variables.When performing a regression analysis the

response variable (criterion) is expressed as a

linear function of regressor variables (predic-tors) and parameters. The coefficient of deter-

Table 4 Pearson correlations ofpretest psychometric variables with post-test anxiety, depression level, and ego strength(n=46)

Pretest scores STAI state after 1 year STAI trait after 1 year BDI after 1 year Ego strength after 1 year

STAI state NS 0.31* 0.33* - 0.46**STAI trait NS 0.47*** 0.55*** - 0.63***BDI NS 0.35* 0.57*** - 0.46**Ego strength NS - 0.53*** - 0.56*** 0.76***Hypochondria NS 0.30* 0.45*** - 0.31**Depression NS 0.38** 0.56*** - 0.52***Hysteria NS NS 0.46** - 0.33*Psychop dev NS NS NS NSMasc/femin NS NS NS - 0.30*Paranoia NS NS NS - 0.30*Psychasthenia NS NS NS - 0.49***Schizophrenia NS 0.33* NS - 0.49***Hypomania NS NS NS NSSocial introv NS 0.32* 0.43** - 0.54***Active coping NS NS NS NSPalliative coping NS NS NS NSAvoiding NS NS NS NSSocial support NS NS NS 0.39*Depressive coping NS 0.42** 0.47*** - 0.51***Exp emotions NS NS NS NSComforting ideas NS - 0.35* NS NS

* p<0.05; ** p<0.01; * p<0.001; NS: not significant.

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Table 5 Stepwise regression analyses with post-test general anxiety (STAI trait), depression level (BDI), and ego strength(Barron's scale) as criteria. (A) Results of step 1; (B) results after step 3 (n=46)

Criterion (post-test) Regression equation (pretest) R2 (Adj R2);p

(A)Trait anxiety (STAI trait) 59.5 - 0.44 Ego strength 0.29 (0.25); p<0.001Depression (BDI) 6.49 - 0.08 Ego strength + 0.14 BDI 0.37 (0.34); p<0.001Ego strength (Barron) 13.3 + 0.79 Ego strength 0.57 (0.55); p<0.001(B)Trait anxiety (STAI trait) 70.21 - 0.04 Ego strength - 0.93 Comf ideas (UCL) 0.35 (0.32); p<0.001Depression (BDI) - 1.98 + 0.14 BDI + 0.08 Depression (MMPI) 0.39 (0.37); p<0.001Ego strength (Barron) 13.3 + 0.79 Ego strength 0.57 (0.55); p<0.001

mination, or R2, is the proportion of thevariance in the criterion that is accounted forby the predictors of the equation; the larger the.R2, the better the fit of the model with the data.The adjusted R' is the R' adjusted for thenumber of predictors and sample size. Becauseof the small size of the group studied (n=46),the regression analyses were performed indifferent phases, each phase with maximumfour predictors included in the regressionmodel (always with post-test general anxiety,depression level, and ego strength as criterionvariables).

First of all, the regression analyses were per-formed with pretest general anxiety, depressionlevel, and ego strength as predictors, because oftheir high correlations with the criterionvariables. The regression equations and the(adjusted) coefficient of determination R' arepresented in table 5A. Post-test trait anxiety(STAI trait) was best predicted by pretest egostrength (adjusted RW=0.25, p<0.001). Pre-test depression level (BDI) and ego strengthwere the best predictors for the post-testdepression level (BDI) (adjusted R2=0.34,p<0.001). The negative sign of the pretestvariable ego strength in these two equationsindicates that the post-test general anxiety andpost-test depression level will decrease aspretest ego strength increases. Pretest egostrength was the single best predictor ofpost-test ego strength (adjusted R2=0.55,p<0.001).

Second, the UCL scales were added one byone in the three regression equations of table5A and successive stepwise regression analyseswere performed. Post-test depression level andego strength could not be better predicted if acoping strategy, measured by the UCL, wasadded, so it was not necessary to adapt theregression equations of the first step. Post-testgeneral anxiety was, however, significantlybetter predicted by a combination of pretestego strength and the coping strategy comfort-ing ideas (adjusted RW=0.32, p<0.001; table5B).

Third, the MMPI scales were included oneby one in the regression equations of thesecond step. None of them added a significantcontribution to predicting post-test trait anxi-ety and ego strength. For the prediction ofpost-test depression level, however, the step-wise regression analysis selected the pretestdepression level (BDI) and the pretest depres-sion scale of the MMPI as best predictors andremoved ego strength from the regressionequation (adjusted R=0.37, p<0.001; table5B).

Fourth, we investigated whether the result ofthe predictive test (carrier/non-carrier) had anadditional predictive value, besides the pretestpsychometric measures already in the model instep 3. The proportion of variance accountedfor did not significantly increase. We also foundno significant increase in the explained vari-ance when gender or age were included in thepredictive model.

DiscussionIn this paper, we present follow up data for thefirst year after the predictive test in the group ofsubjects who received a result in a genetic cen-tre in Flanders. Although the sample size issmall, the study shows some general trends at agroup level. On average, receiving bad newshad no significant impact on anxiety, depres-sion level, or personality, as measured in thisstudy. In other words, in general, the certaintyof being a carrier seemed no worse or betterthan uncertainty about one's carrier status. Fornon-carriers, however, knowing was, on aver-age, better than not knowing: the mean anxietyand depression levels had significantly de-creased one year after the test. Mean egostrength and personality profile did not signifi-cantly change. It is important to keep in mindthat averages mask individual reactions. Al-though there have been no psychiatric prob-lems, about 10% of the subjects tested, carriersas well as non-carriers, had a mild depressionlevel or a high level of trait anxiety, or both, inthe post-test period. In general, test applicantswith pre- or post-test anxiety or depressionscores above average receive extra attentionduring the counselling sessions.The overall findings on anxiety, depression,

and personality elicit optimism about predic-tive testing for HD. They should, however, notbe merely generalised to the total at risk popu-lation. Indeed, psychometric testing in the pre-test period6 showed that test participants are aself-selected group with good ego strength andpositive coping strategies. Moreover, theyreceived extensive pre- and post-test psycho-logical counselling and support. Kessler"'suggested that the arduous testing protocolsused by some centres may act as a screen todiscourage all but the most motivated anddetermined people to proceed with the test. InFlanders, test participants have at least threecounselling sessions and a neurologicalexamination before they make the final deci-sion and before a blood sample is taken. Theseelements may play a role in explaining the gen-eral low rate ofhigh anxiety and depression oneyear after an unfavourable test result. Denial

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and minimisation of the impact of the resultmay be an additional explanation.'" 24 Thesepsychological defence mechanisms give carri-ers the opportunity to adapt unconsciously tothe painful information about the future. Theyare maladaptive if the test result is notintegrated into daily life, for instance, in thedecision making process about procreation.The test did have a definite influence on

family planning. Two thirds of the carriers withreproductive plans decided to refrain fromhaving children or to have a prenatal diagnosis.Most non-carriers with reproductive plans hadopted for a pregnancy. It is clear that their car-rier status confronts the person with new prob-lems and dilemmas in their reproductive deci-sions. Deciding to refrain from having childrenor to perform prenatal testing with a 50% riskof a pregnancy termination may indeed be veryburdensome. The fact that one at risk womanwas already pregnant before she received herresult and that some others stopped contracep-tion months before receiving the test resultshows that reproductive decisions are verycomplex and subject to emotional and uncon-scious processes, especially in a genetic con-text."'333 34

Pre- and post-test measures of general anxi-ety, depression, and ego strength were signifi-cantly intercorrelated. One coping strategy ofthe UCL (Depressive coping) and severalMMPI scales (Hypochondriasis, Depression,Hysteria, and Social Introversion) were alsosignificantly correlated with post-test generalanxiety, depression level, and ego strength. Thescales Hypochondriasis, Depression, and Hys-teria are referred to as the "neurotic triad".23The systematic correlation of this triad withthe post-test anxiety, depression, and egostrength suggests that the more neurotic an atrisk subject is before the test, the more anxiousand the more depressive he will be after the testand the less ego strength he will have, whateverthe result is.

Stepwise multiple regression analyses wereused to select the best predictors from the pre-test variables to predict individual post-testgeneral anxiety, depression level, and egostrength. The analyses showed that post-testgeneral anxiety was best predicted by a combi-nation of the pretest ego strength and the pre-test coping strategy comforting ideas. Copingby means of comforting ideas refers to encour-aging oneself by inner speech and having gen-erally optimistic thoughts. Post-test depressionwas best predicted by pretest depression level,measured with the BDI, and with the depres-sion scale of the MMPI. A prediction ofpost-test depression level by means of pretestdepression level (BDI) and the scale egostrength of the MMPI was nearly as good. Pre-test ego strength was the single best predictorof post-test ego strength. Test outcome(carrier/non-carrier), gender, and age of thepersons tested did not significantly contributeto the prediction of post-test trait anxiety,depression level, and ego strength. The reasonfor the lack of predictive power of thepredictive test result is the large variation (SD)of pretest and post-test anxiety, depression,

and ego strength scores and their large overlapin the carriers and non-carriers.The results indicate that a careful evaluation

of pretest depression, ego strength, and copingstrategies may be helpful in predicting post-testreactions, independently of carrier status. Theyconfirm the impact of ego strength in copingwith a predictive test result. Barron'2 suggestedthat people with higher ego strength may alsoprofit more from counselling and psycho-therapy than persons with lower ego strength.The findings are also in line with the

viewpoint of Wexler'" who argued that some atrisk subjects would probably benefit more frompsychotherapy than from a predictive test. Thepredictive test result had no additional predic-tive value in predicting individual reactions oneyear after the test. Other factors, such as pretestego strength and depression, were morepredictive. Therefore, it is important thatdepressive test participants or those with a lowego strength, who attribute all their fears andworries to their genetic risk, and who believethat all their problems will be solved after thetest, should receive extra attention during pre-test psychological counselling to anticipate anddiscuss possible remaining anxieties and diffi-culties, irrespective of the test result. Only aproportion of the variance of the post-testanxiety, depression, and ego strength (maxi-mum 32%, 37%, and 55%, respectively) wasexplained, implying that other psychological/social aspects should also be taken intoaccount when predicting individual post-testreactions (for example, support of the partner,condition of the affected parent, survival guilt,uncertainty about the moment of onset of thedisease).Two critical remarks should be remembered

when interpreting the findings. First, the roleof the self-selection of the test participants andof the pre- and post-test psychological counsel-ling should be kept in mind when interpretingmild post-test reactions, and pre- and post-testcounselling and support should not be ne-glected as the test becomes more widely avail-able. Second, we can not exclude that the lowincidence of psychological problems is partlythe result of a denial of distress. However, ifthis phenomenon was present, it did not occurto the extent that the predictive test result wasnot taken into account in reproductive decisionmaking. Further systematic longitudinal followup of carriers and non-carriers is needed, notonly to provide psychological support to thetested person, but also to evaluate long termpsychological and social effects of the predic-tive test.

1 Harper P. Huntington's disease. London: Saunders, 1991.2 Gusella JF, Wexler NS, Conneally PM, et al. A polymorphic

DNA marker genetically linked to Huntington's disease.Nature 1983;306:234-8.

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5 Evers-Kiebooms G. Predictive testing for Huntington's dis-ease in Belgium. J Psychosorn Obstet Gynecol 1990;1 1: 61-72.

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12 Barron F. An ego-strength scale which predicts response topsychotherapy. ] Consult Clin Psychol 1953;17:327-33.

13 Babul R, Adam S, Kremer B, et al. Attitudes toward directpredictive testing for the Huntington Disease Gene.Relevance for other adult-onset disorders. JAMA 1993;270:2321-5.

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