POSTGRAD. MED. J., (1966), 42, 86

Case Reports

ANOREXIA NERVOSA IN AN IDENTICAL TWIN

A. CRISP, D.P.M., M.R.C.P

Academic Psychiatric Unit, Middlesex Hospital,London, W.1.

RECENT papers (Crisp 1965a, 1965b, Russell 1964,1965) have been concerned with the possilble inter-relation and significance of hypothalamic, peri-pheral metabolic and psychological factors forthe genesis of anorexia nervosa. As a clinicalphenomenon, anorexia nervosa is a fairly discreteentity and Bliss and Branch (1960) have attributedthis mainly to the uniform symptomatology char-acteristic of "nervous malnutrition". They pro-pose that this psychobiological posture can have avariety of social and psychological determinants.Other workers agree that anorexia nervosa can besubdivided usefully into primary and secondaryforms and that the primary form may again meritsubdivision (Meyer 1961, King 1963). More re-cently Crisp (1965b) has suggested that "itypical"anorexia nervosa is characterised 'by certain pre-morbid nutritional features which may havefamily "psychosomatic" determinants and implica-tions. Moreover, the disorder often seems to arisethrough overdetermination of dieting behaviourwhich has become inadvertently incorporatedduring adolescence into resolving intense post-pubertal emotional conflict. Any genetic basis thedisorder has, so far as its nutritional nature isconcerned, is at least as likely to contribute tothe premorbid metabolic and nutritional "set",which is often one associated with over-nutrition,as to the disorder itself. In this connection it hasbeen suggested (Crisp 1965b) tfhat the anorexianervosa proband is already nutritionally differentat birth from her sister siblings but that this dif-ference may in part be due to differences in in-trauterine nutrition which are not themselvesgenetically determined.Only one report of anorexia nervosa in pre-

sumed identical twins (i.e. the sibs were of thesame age and sex and looked identical) has been

found in the literature (Meyer 1961). These twinswere insitially concordant for the disorder but laterone of the twins recovered. They were raisedtogether and are reported on as having had verysimilar environmental experiences in childhood.During childhood they were both well nourishedand they had early and concordant menarchesaround the age of 12. Their illnesses developedsimultaneously at the ages of 17 when they bothunderwent similar unhappy experiences. The twinwho recovered was reported on as having begunto make a heterosexual adjustment as her illnessremitted. Soon afterwards she married, remainedclinically well, and now has two children. Theother twin's symptoms became more entrenchedat this time of separation and her life situationremained severely restricted. She was consideredby some psychiatrists to have developed schizo-phrenia. H-owever, Meyer believes that the illnesshad merely taken on the features of chronicanorexia nervosa and, from the description of thecase, this would seem to be so. TIhis case reportsuggests that environmental determinants of thedisorder may be important since initial concord-ance was associated not only with presumed iden-tical genetic endowment but also with identicalupbringing, while the twins' ultimate capacity fordiscordance for anorexia nervosa was revealedduring a time in which their life situations andexperiences diverged. Jt cannot be concluded fromthis case report however, that this latter phe-nomenon was necessarily causal to the remissionof the illness. The present author has also heardof two other female patients with anorexia ner-vosa who are presumed identical twins and whoa,re discordant for anorexi,a nervosa. Jn the firstof these cases (Tibbetts 1965) the proband issaid to have developed her illness at the time

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TABLE 1ZYGosITY DATA

Proband Co-Twin

Sex Female FemaleHeight 5' 41" 5' 5"Androgyny Score 80 78Eye Colour Blue BluePTC taste test Taster (Solution 9) Taster (Solution 9)Handedness Right Right

EEG The EEG is in both cases dominated by a 'high voltage 11-12 c/s responsivealpha rhythm. 4-7 c/s intermediate slow ,and 1-3 c/s slow frequencies are wellrepresented in 'both cases. Atypical fast bilateral spike and wave discharges occurfrequently in the co-twin's record and less often in the probland's record. Thedischarges are enhanced in both cases by overbreathing and, in the co-twin, byphotic stimulation.

Blood Grouping A,, NSNs, P, , rr, Lu (a-), K+, A,, NSNs, Pi, rr, Lu (a-), K+,Probability monozygotic on Le (a-b+), Fy (a+b+), Xg (a+) Le (a-'b+), Fy '(a+b+), Xg (a+)blood grouping + like sex _y(by Smith and Penrose 955method 1955)

Finger prints 189 182Total count VProbability monozygotic .78on fingerprints (bySlater method 1963)

when her sister won an important 'beauty compe-tition. It was thought that this was the final stress,in an ongoing state 'of si'bling rivalry, which pre-cipitated her illness. She eventually recoveredspontaneously and is now engaged to be married.In the second case (Willis 1965) the proband issaid to have become ill at the time when her sisterbecame engagetd to 'be married Jn both cases theproband was considered to have ibeen "immature"premorbidly and was regarded quite definitely asbeing the non-dominant member of the twinship.

Case HistoryThe present report is of an identical twin, whose

identical twinship 'has been established beyond allreasonable d'oubt '(Table 1), and who has sufferedfrom anorexia nervosa in which respect she is dis-cordant with her twin sister. The patient, aged just22, was referred by a general physician to whomshe had been sent for investigation of her amenor-rhoea. Her complaints were "I'm feeling rather de-pressed; I've gone off potatoes, bread and things,although I still feel 'hungry; I sleep poorly".She was born in December 1940, the first of iden-

tical twins. The labour was uncomplicated. At birththe patient weighed 5 lb. 4 oz. and her sister weighed5 Lb. 0 oz. She described her mother as an affec-tionate but tense irritable person, given to periods ofsilence lasting several days if offended by the patientor her father. A maternal aunt was described as an"alcoholic" and the maternal 'grandmother was said

to be given to bouts 'of depression. She described herfather, a prosperous stock-broker, as a shy, un-affectionate man. There was no family history ofundue obesity, leanness or unusual feeding habits.She said that her mother 'had frequently told herthat, on learning late in pregnancy that she wasgoing to have twins, she felt "she could not copewit'h more than one child without the support ofDaddy". The father was away in the Armed Forcesfrom 1940-1944. Neither twin was breast fed, thereason given being that there was insufficient ma-ternal milk. The patient had always 'been regardedas the more passive and submissive of the twins. Thepatient's earliest memories were of the house beingbombed and of her recurrent illnesses, mainly "colds"and "bronchitis", which interfered with 'her schooling.The twin sister more often evoked criticism andpunishment from the parents and was perceived by'the patient as lbeing jealous lof the patient's frequentabsences from school which enabled her to be athome with her mother. The patient said that herfather had never shown any overt affection to eitherof them since his return to the home when theywere aged 4 years.

Both twins were well nourished during childshood.During this time they both bit their nails excessivelyand the patient described herself as having been"pretty highly strung". She recalled that she hadalways been very anxious and shy in company andparticularly distressed and anxious to "cover up" forher sister when the latter was under criticism. Whenthe patient was aged 11 the mother developed pul-monary tuberculosis and spent some months in hos-pital. During this time the patient recalled that she

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8POSTGRADUATE MEDICAL JOURNAL

TABLE 2

Test [ Proband Co-Twin

Chest X-RayHaemoglobinWBC Total

Differential-neutrophils-lymphocytes-monocytes-eosinophils

ESRAugmented Histamine Test

for gastric acidity

Resting Juice1 hour before histamine1 hour after histamine

S. Electrolytes-Cl-K-Na

Blood-UreaS. CholesterolS. MiagnesiumBlood P,roteins-total

-albumen-globulin

Electroph-oretic patternBMRGastric Motility

(Telemetering pill)Random blood sugars

Oral GTT-Fasting-30 min.-60 min.-90 min.-120 min.

Before treatment

Normal98% 14.2 g.%4,600 /cu. mm.67%30%2%1%

2 mm./ls't hourFree HCI. ml.

N

10

319

11799 mEq/l.4.6146,,51 mg./100 nml.4002.16.6 g./100 ml.4.02.6Normal-18%

Vol. ml.

106355

Normal68 mg./100 ml. (mean of

13 samples)55 mg./l00 ml.101 ,,140 I

101 ,,75

After treatment

81 % 11.8 g. %6,600/cu. mm.

72%19%9%

8 mm./ls-t hour

96 mEq/l.4.2150 ,

41 mg./l00 ml.350 ,2.1 ,,

-1%

Normal

97 mEq/1.5.1145 ,

36 mg./l00 ml.270 ,,2.2 ,,7.1 g./l00 ml.4.2 ,2.9 ,,Normal+2%

6589929876

mg./1I00 ml.,,9

,,

,,~

,,9

became increasingly aware of disharmony betweenher parents and of her father's temporary attachmentto a younger woman. Subsequently the threat ofseparation between her parents increased and tfhemother is said to -have used her daughter as a con-fidante, discussing her own frigidity, her disgust withsexual matters, 'her husband's tendency to be "over-sexed" and his inability to provide any emotionalsupport in the home. She is said frequently to havetold the twins at this time that it was only they whoprevented -her from leaving her husband.The patient reported her menarche as having

occurred at the age of 14 years and 3 months andher sister's at the age of 12 years and 6 months. Thiswas confirmed by the parents. The twins were ini-tially privately educated and then, at the age of 11,they went as day pupils to a Roman Catholic GirlsPublic School. Around this time the patient beganto feel 'bewildered by the increasing social demandsimposed on her. She began to mimic her twin intheir joint social activities. She became afraid ofanswering 'the telephone. Both twins did well at

sport and became expert horsewomen. School con-temporaries of the twins have reported that theyfound the proband a "kind, sweet, friendly person"and her sister "a more irritable, egocentric person".The patient unexpectedly gained only 4 "O" levelsin the G.C.E. Her sister gained 6 "O" levels.At the age of 13 the patient had a "crush" on a

local iboy but became frightened by his demands onher to kiss and cuddle him. She withdrew from therelationship. Around tihe age of 17 her sister becamemore interested in boys and began to go out on herown. The patient determined to show a similar in-terest and became friendly with a 17-year-old boy.He began to make physical sexual demands uponher and she felt "disgusted" and "unmoved". Themother recalled that at this time she was plump.The patient denied this at interview. She recalledthat she began to feel she could not eat potatoesand puddings when in iher boy friend's house. Shortlyafterwards she gave up this 'boy friend. She alsobegan at times to abstain from meals at home whenher sis-ter was not there, particularly if her parents

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TABLE 3GLUCOSE TOLERANCE AND INSULIN RESPONSE TO INTRAVENOUS INJECTION OF

25 g. GLUCOSE i(PROBAND)Before treatment During treatment End of treatment

Sugar Insulin Sugar Insulin Sugar Insulinmg./I100 ml. uU /Iml. mg. / IlOO ml. tu /Iml. mg. / IlOO ml. ou /Iml.

Fasting 43 14 81 66 195 mins. 261 29 237 259 110

10 mins. 272 26 217 224 701 5 ,, 244 25 20020 ,, 170 1642530 ,, 230 23 135 110 47354045 ,, 200 27 95 69505560 ,, 174 26 60657075 ,, 2780 ,, 170K Values 0.89 2.5 3.47

were quarrelling. She became increasingly depressed.She and her sister remained united in their joint andincreasingly devoted interest and activities within anauthoritarian and evangelical section of the Church.The parents resented this particular interest andfrequent quarrels ensued over the twins' attempts toconvert them.

After leaving school she spent 6 months at homeand then started a secretarial training. At the age of18 she underwent appendicectomy; a normal appen-dix was found. Subsequently she embarked upon anursing training for 6 months but felt "homesick"and abandoned it. A second attempt at nursing train-ing also failed although she did particularly well inher preliminary training. At this stage she was re-ferred to a psychiatrist with complaints of depressionand some slight weight loss. She attended for a fewinterviews. Subsequently she became slightly lessdepressed and regained some weight. The patientwas now 20 years old. Her sister became friendlywith a man and announced to the patient her inten-tion to marry 'him. The patient recalled that at thistime she determined to diet systematically "becauseI intended taking a secretarial job which would besedentary". Amenorrhoea supervened within 2 monthsof her starting to diet and before there was anynoticeable weight loss. During the next 18 monthsthe patient lost weight steadily from 8 st. down to 6 st.She found that she was now somewhat less depressedand that "My feelings aren't hurt so much now".She found it was increasingly difficult to sleep andin particular began to wake early in the morning.She 'became preoccupied with her weight and withdaily weighing; she began to experience anxiety andguilt if there was any weight gain and relief ifthere was none. She became excessively interested incooking and preparing food for 'her parents. Sheconsistently refused ito eat any reasonable quantityof carbohydrate. She 'became -increasingly orderly,conscientious and' concerned -over cleanliness, alsomore sensitive and prone to periods of silence. Shebecame increasingly active iand concerned to exercise

herself with long walks. She continued to worksatisfactorily and was free from intercurrent illness.At this point she was referred to hospital.During the initial interview with the parents, their

incompatibility 'became apparent; also their commonconcern for t'he patient's health.The mother, when seen alone, described her hus-

band as a most dependent, unaffectionate man whohad seemed jealous of her relationship with the twinsfrom the time that he returned home after the war.She contemptuously described his frustrated sexualneeds in relation to herself and disclosed that hefrequently "eyed" 'adolescent girls and that on oneoccasion 'he had narrowly avoided being chargedwith importunate behaviour on a railway train. Shean'd the patient denied th'at 'he was attracted to thepatient in this way or that the patient had everattempted to evoke affection from him -by behavingseductively towards him. Such behaviour, however,emerged later as a transference phenomenon!The father described his wife as 'an embittered

domineering person who had suffered an unhappychildhood and who had subsequently battled againstmany difficulties of a 'physical and emotional kindin her married life. He confirmed the account of hiswife's frigidity.The twin sister, who expressed and revealed con-

siderable feelings of guilt about her sister's illness,gave an account of the family background which wassimilar to the patient's account. The twin sister hasremained in a normal physical, nutritional and dietarystate throughout her life and has never sought psy-chiatric help. Her weight has been steady at about9 st. since her mid-teens.On Examination: Mental State. Simply dressed, care-

fully and modestly toileted, submissive, child-like inposture, manner and voice. Mood-at times respon-sive and smiling; at other times quiet and still;tearful when discussing the ways in which she issometimes compelled by others to eat. Expressingideas of hopelessness; that she will never be normal,will never marry and will end up iby killing herself.

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Admits to being preoccupied with thoughts of foodand with a fear of gaining weight.

Physical Examination. Emaciated girl; relative re-tention of breast fat. Weight 5 st. 12 lb. B.P. 90/65mm. Hg. Pulse rate 56/min, regular. Body tempera-ture 96°F; cold blue extremities. Downy hair overshoulders and back.

Investigations. Table 1: Zygosity Data.Tables 2 and 3: Other Investigations.

Treatment. The patient was put to bed and estab-lished on chlorpromazine 100 mg. t.d.s. and a re-feeding regime (Crisp, 1966). Psychotherapy wasstarted and has since continued on a once-weeklybasis '(120 sessions). The patient gained weight up to72 st. over t;he period of the first 6 weeks. At thispoint her twin sister married. The patient attendedthe wedding and behaved histrionically. Immediatelyafterwards she insisted on leaving hospital and goinghome permanently. She anticipated spending severalmon,ths at home with her mother alone. Within afew days the patient was quarrelling with her motherand refusing to eat. She became depressed and lostweight. She was re-admitted to hospital. Anti-depressant drugs (imipramine 50 mg. t.d.s. and, later,phenylzine 15 mg. t.d.s.) were given for adequateperiods of time and did not lead to any improvement.However, the patient claimed that perphenazine 4mg. t.d.s. relieved 'her of tension feelings. The patientspent 4 months in hospital. If allowed home forweek-ends she would either abstain fr'om eating or,when she visited her twin sister, she would overeat.She became gradu,ally less depressed whilst in hos-pital and was encouraged to take up temporarysecretarial work. On discharge from the hospital shereturned home. During the next 2 months she workedfairly well. She began to take an interest in socialactivities but felt very anxious when she attendedone,or two parties and was not able to participate inthe general conversation and dancing. At this pointher mother started drinking alcohol excessively,having been a moderate daily social drinker for manyyears. The mother attributed this increased drinkingto the stresses imposed on her by the major rowswhic'h were now occurring frequently between thepatient and her father. Her father was reported onas becoming increasingly impatient and irritable withthe patient. She was obviously anxi-ous at this timeto spend as much time with him as possible. Thepatient began to lose weight and again gave upwork. She then made two successive suicidal attemptswhich were ineffectual in their probably main intentto alter the parental attitudes towards her and to-wards each other. The parental attitudes remainedthose of apparent concern for her but the motherwas becoming increasingly exasperated. The patientate nothing for 10 days and was re-admitted tohospital in a state of collapse. She remained inhospital for the next 11 months. Initially she under-went a course of modified insulin treatment. Thiswas associated with increased food intake in themornings and some weight gain, but her eating be-haviour became more unstable, with bouts of bulimialeading to anxiety'and depression followed by one ortwo days of total abstinence from eating. Duringone of the hypoglycaemic episodes induced by theinsulin she developed a grand mal seizure (con-sistent with demonstrated EEG vulnerability). Over-all the patient remained depressed. A course of 13ECT was not associated with any improvement.

Psychotherapy continued and the patient was be-

ginning to express intense feelings of hostility towardsher sister and her mother. She also began to in-creasingly express an awareness of her uns,atisfiedneeds for affection and security in relation to herparents. It became clear, from several informants,that the twin sister was egocentric and had ofteninterfered with the patient's few feeble attempts todevelop other relationships by taking them over her-self. It emerged that the twin sister's husband hadoriginally met and shown some benevolent interestin the patient but that the twin had "stolen" him.The patient developed an intense dependence uponthe ward staff and on several other patients. Sheremained child-like in her manner and speech. Shedeveloped a dependent and flirtatious attachment tothe therapist which was regarded as a direct "trans-ference" from her relationship with her father andprogressively interpreted as such. She slashed herwrists, inflicting venous bleeding, on several occa-sions during this period of several months. Thisbehaviour was regarded as acting out behaviourwithin the "transference" and interpreted as such.She was eventually told that she must not repeat thisbehaviour if she wished to remain in therary. Thebehaviour ceased. It was not until some intensivepsychotherapy was done with the parents howeverthat she began to improve. The mother had beenin individual psychotherapy, occurring once everyfew weeks, for about 10 months. She had remainedresistant to being involved in the treatment process.Now the therapy was conducted jointly with bothparents together with a therapist. The father wasable to discuss his own feeling of inadequacy andhis sense 'of rejection for the first time ever with hiswife in these sessions. Subsequently he was able toadopt a more positive role in the family. The patientwas able to spend several week-ends at home. Shebegan to eat more normally and slowly gained weightover the next 2 months. Menstrual bleeding recom-menced. It became apparent that it would be betterfor her to live away from home for the most part,if a suitable protective milieu could ibe found. Thisproved possible and the patient was discharged fromhospital. She continued to have similar emotionaldifficulties from time to time and remained ob-viously dependent on those around her. Howeverher feeding behaviour became less sensitive ,to thesedifficulties and she was less depressed. She made onemore suicidal gesture when her twin sister went intolabour. She was subsequently able to recognise thisas being in part a hostile act against 'her sister.Psychotherapy is continuing. Regular monthly men-strual bleeding has now been present for the last 9months. Her weight remains fairly steady at around9 st.

DiscussionA case of anorexia nervosa in a female identi-

cal twin is reported. The probability (based onzygosity data) that these twins are other thanmonozygotic is so small that it can be ignored.The case history, taken from the patient andother informants, together with further explora-tion and psychotherapy, suggests that the patienthas always been the more passive and submissiveof the twins; furthermore that her feelings ofanxiety, sensitivity and insecurity were intensifiedaround the iage of 13 and 14, alt the itime of hermenarche and also at the time when her fears ofdisharmony and threat of separation between her

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parents became increasingly confirmed. At thistime her mother used her as a confidante in des-cribing her father's inadequacies and his "ex-cessive" sexual demands unaccompanied by in-terest in or suppoirt for the famiily. There wassome evidence that the father's behaviour at thistime was a reaction to his wife's earlier neurioticrejection of him. The patient intensified her life-long attempt to evoke, to her own satisfaction,demonstration of affection by her father towardsherself. She failed. In this situation the patientcame to increasingly rely upon and mimic hertwin sister, feeling that she (the patient) had noseparate identity. By this she meant that, pro-viding she stayed with her sister and imitatedher 'behaviour, she remained apparently sociallycompetent. If required to act alone, however(e.g. to answer the 'phone) she would feel panicand usually withdraw from the situation. Shesucceeded in this behaviour until her sister, withwhom she had a complex and intensely ambivalentrelationship, began to develop separate hetero-sexual interests. The patient's attempts to followsuit in seeking affection outside the home and tolead a similar independenit life were associated wilthfeelings of isolation, panic and digust. As thethreat of separation between her parents becamemore imminent the patient abandoned all attemptsat developing peer relationships. She becameincreasingly depressed and at the same timebegan to avoid meals and in particular theircarbohydrate content. At 'the time when hersister's engagement to be married became immi-nent the patient developed severe anorexianervosa. This illness, which was associated withcessation of what had 'been tentative but frighten-ing postpulbertal activities for her and duringwhich she was also able to relinquish her closerelationship with her twin sister without express-ing her hostile feelings and without feeling asdistressed as she had anticipated she would, alsoled to her being thrust back into an unsatisfyingand increasingly neurotic relationship with herparents. However, the mother's earlier threat toleave the home did not materialize and the patientnow believes that her illness has had the effectof preventing her parents separating from eachother.Psychotherapy was directed toward the patient

and her parents. It was concerned to enable thefamily to communicate with each other morefreely and directly, particularly over mattersconcerning their own interrelationships andindividual needs and feelings towards each other.Effiorts were also made to help the patient,mainly by interpretation of the 'transference' andof other 'here and now' behaviour and also byencouraging her to undertake social activitieswithin the therapeutic milieu. This was associatedwith slow progress and the patient eventuallycame more easily to (be able to dissociate herfeeding 'behaviour from her emotional conflicts.The latter 'have persisted until the present timebut she is now more able to cope with them.

The ways in which such conflicts may come,in anorexia nervosa, to involve feeding behaviourhas 'been discussed elsewhere. Jn this patient, herbirth weight was X lb. more than her sister's. Thisdiscrepancy, though small, is in the same directionas the significant discrepancy between the maingroup of patients and their sister siblings (Crisp,1965'b). In the present case it presumably reflectsdifferences in intrauterine nutrition of a non-genetically determined kind. During childhoodboth twins were well nourished although thepatient was regarded as more 'faddy' than hersister. The patient's menarche is reported on ashaving occurred later than her sister's. Thisfinding is not typical of the main group ofpatients. Furthermore, this reported discrepancybetween the twins' menarches of 1 year and9 months is a much greater one than that usuallyfound in identical twins (Tanner, 1962). Duringthe two or three years following her menarchethe patient is reported on 'by her mother ashaving been somewhat plumper than her twinsister 'but the patient denies this.

Investigation of glucose tolerance in the healthytwin and in the patient before treatment showeddlifferences between the twins in their responseto 50 g. oral glucose. The normal twin showeda more normal response consistent with thatoften found in healthy young people. The pro-band, both in response to 50 g. oral glucose andlater, 25 g. i.v. glucose, produced a high andsomewhat delayed response. This may have beendue to defective utilization '(Crisp, 1965b) or elseto differences in the glucose space between thetwins. Such a response is a chlaracteristic findingtowards normal (reflected in increasing K values)in starvation and, in the proband, it returnedon refeeding. However, the insulin response ofthe proband to an intravenous injection of 25 g.glucose both 'before and after treatment showeda sustained type of response which has elsewherebeen shown (Crisp, 1965b) to be a characteristicof a group of anorexia nervosa subjects in whichrespect they were different from nonnals. Further-more, two of the anorexia nervosa subjects inthis latter study showed the same type of responseone year after full clinical recovery from theirillnesses.The patient's BMR was characteristically low

before treatment and returned to within normallimits following weight gain and restoration ofmenstrual bleeding. This patient almost certainlydid not vomit or purge herself excessively and themajority of the blood tests carried out haveprovided predictably normal results although therelatively high haemoglobin and blood ureabefore treatment compared with after treatmentsuggests that there was some initial dehydrationpresent. However, the patient's serum cholesterolwas substantially raised 'before treatment andwas somewhat lower at the end of treatment.This has been a common finding amongst thetotal patient group. It may reflect to some extentthe large quantities of cheese that this patient,

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like the majority of patients, ate while ill; alsobe related to the infrequency of her meals (Fabry,Fodor, Hejl, Braun and Kamila, 1964).

SummaryA case of anorexia nervosa in a confirmed

identical twin is reported. The proband is dis-cordant with her twin sister for the illness. It issuggested that the predeterminants of anorexianervosa are predominantly environmental. Thus,despite their identical genetic endowment thesetwins were regarded as different in personalityfrom an early age (a common finding withidentical twins, Parker, 1964). Equally, theirnutritional status, which was probably alreadydifferent at the time of birth, has remainedslightly different. It is suggested that thesepossibly interrelated premorbid factors may havepredisposed the patient to develop anorexianervosa when confronted by adolescent conflicts.Thus, the patient's life-long feelings of insecurity,which ill-prepared her for an adult independentlife, were intensified around the age of 17 whenher parents threatened to separate from eachother while at the same time her twin sister-began to develop independent interests. Thepatient, with her intense social anxiety, equallyintense need for affection together with herdisgust of 'sex' (the latter possibly engenderedby her mother's attitude to her own marriage)was unable to find suitable heterosexual peerrelationships. The patient's illness may beregarded as a disorder of nutrition which hasbeen associated with avoidance (biologically andsocially) of further postpubertal activity, whilsther persistent inability to eat and her childlikebehaviour has been associated with enhancedand exclusive dependency on her parents who infact have not separated. Her new-found and nowalmost immutably dependent relationship withher parents had become an increasingly neuroticone. Psychotherapy, directed towards the patientand the parents, has been associated with gradualrecovery of the patient, who is now ratherbelatedly, but more confidently, retesting out her'adolescent' life situation At present she is less

prone to use abnormal feeding behaviour in herattempts to resolve recurring anxieties arising inthis situation.The author wishes to express his gratitude to

Professor Denis Hill, under whose care the patientis, for his help and advice, Miss M. Bailey,P.S.W., and Dr. Eugene Wolf, who conducted thetherapy with the parents; also Dr. N. Parker andMr. J. Shields of the Psychiatric Genetics ResearchUnit, Maudsley Hospital, London, iSE.5, and Dr. R.Sanger of the Blood Group Research Unit, ListerInst., Chelsea Bridge Road, London, S.W.1, for theirhelp with the zygosity determinations.

REFERENCESBLISS, E. L., and BRANCH, C. H. (1960): Anorexia

Nervosa, New York: Paul B. Hoeber.CRISP, A. H. !(1965a): Clinical and Therapeutic

Aspects of Anorexia Nervosa: a Study of 30Cases, J. psychosom. Res., 9, 67.

CRISP, A. H. (1965b): Some Aspects of the Evolution,Presentation and Follow-up of Anorexia Nervosa,Proc. roy. Soc. Med., 58, 814.

CRISP, A. H. (1966): A Treatment Regime forAnorexia Nervosa, Brit. J. Psychiat. In press.

FABRY, P., FODOR, J., HEJL, Z., BRAUN, T., andZVOLANKOVA KAMILA (1964): The Frequency ofMeals, Lancet, ii, 614.

KING, A. (1963): Primary and Secondary AnorexiaNervosa Syndrome, Brit. J. Psychiat., 109, 470.

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'PARKER, N. (1964): Close Identification in TwinsDiscordant 'for Obsessional Neurosis, Brit. J.Psychiat., 110, 496.

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