Polycystic ovary syndrome and bulimia*

Vol. 55, No.2, February 1991

FERTILITY AND STERILITY

Printed on acid-free paper in U.S.A.

Copyright e 1991 The American Fertility Society

Polycystic ovary syndrome and bulimia*

Sara McCluskey, M.R.C.Psych.t* Christopher Evans, M.R.C.Psycht J. Hubert Lacey, F.R.C.Psycht:\:

J. Malcolm Pearce, M.D.§ Howard Jacobs, F.R.C.P·II

St. George's Hospital Medical School, London, and The Middlesex Hospital, London, United Kingdom

One hundred fifty-three patients classified as suffering from polycystic ovarian syndrome (PCOS) and 109 patients who were suffering from a clear organic disorder or endocrinopathy received the bulimia investigation test (Edinburgh) (BITE) questionnaire for abnormal eating behaviors. Patients with PCOS showed a significant increase in their mean BITE score for approximately a third had abnormal eating patterns, and 6% have scores suggestive of clinical bulimia compared with only 1 % of women in the group with organic endocrinopathies. The work suggests that women with PCOS should be screened for abnormal eating behaviors and raises the possibility that treatment by psychological means should be considered when abnormal eating behaviors are present. Fertil SteriI55:287, 1991

Disturbances of menstruation are common in both the eating disorders 1 and the polycystic ovarian syndrome (PCOS}.2 Amenorrhoea is one of the diagnostic criteria for anorexia nervosa, 3 and recently the less well-known condition of bulimia has been described as being associated with infrequent periods or amenorrhoea even in the presence of normal body weight. 4 ,5 Bulimia is characterized by gross binge eating with normal body weight maintained by such measures as starvation, self-induced vomiting, and laxative and diuretic abuse. 5 Both PC OS and binge eating are common disorders of the female population with a prevalence of 26%6 and 21 %,7 respectively, so we set out to determine if there was a relationship between PCOS, binge eating, fasting, and bulimia.

Received April 11, 1990; revised and accepted October 1, 1990. * Supported by the Special Trustees of St. George's Hospital and the Priory Hospital, London, United Kingdom. t Adult Psychiatric Department, St. George's Hospital. :j: Requests for reprints: J. Hubert Lacey, F .R.C.Psych., Adult Psychiatry Department, St. George's Hospital Medical School, London SW17 ORE, United Kingdom. § The Fetal Welfare Laboratory, St. George's Hospital. II The Endocrine Unit, The Middlesex Hospital. Vol. 55, No.2, February 1991

MATERIALS AND METHODS

Three hundred seventy-five women attending a specialist endocrine clinic at the Middlesex Hospital were asked to fill in a self-rating scale for bulimia known as bulimia investigation test (Edinburgh) (BITE}.8 This consists of a symptom scale that consists of 30 questions to investigate habits of dieting and symptoms and behavior associated with binge eating (see Appendix). Patients were classified, according to their score, as being at high, medium, or low risk of suffering from the disorder bulimia nervosa as defined by the American Psychiatric Association. 3 Patients who scored above 20 were considered at high risk of having bulimia; those with a score of 10 to 19 did not fill the diagnostic criteria but were considered to have a subclinical eating disorder; those with scores of <10 were considered to have normal eating patterns. The BITE questionnaire also has a severity scale made up of a further six questions (see Appendix) that are designed to determine the frequency of binge eating, fasting, self-induced vomiting, and abuse of laxatives, diuretics, or appetite suppressants. This questionnaire has been validated in large populations of women and is found to be both highly sensitive and specific.9 Patients were seen by a clinical endocrinologist McCluskey et aI.

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who was unaware,.of the results of the questionnaire and who classified the patients into three groups as follows: 1. Those women suffering from PCOS. Such patients had polycystic ovaries demonstrable on ultrasound (US) examination in that the ovaries contain > 10 cysts of 2 to 8 mm in diameter arranged peripherally around an ovarian stroma of increased echogenicity.lO They also met the clinical and endocrinologic diagnostic criteria of Conway and colleagues. 2 2. Women suffering from organic disorders and endocrinopathies. Details of these women are given in Results. The diagnostic criteria were standard and based on endocrine assays, ovarian US, electroencephalography, and computerized axial tomography as indicated. These women were used as a control group because they had clear organic disorders in which weight, diet, and psychiatric disorders are not thought to be of major etiologic importance. 3. A group of women who met the criteria for neither of the above groups and was subsequently excluded from analysis. All patients had their age, weight, and height recorded, and their body mass index (BMI) (weight/ heighe) was calculated. l l The BITE symptom score, age, and BMI were normally distributed, and relations between these three outcome measures were, therefore, tested using Pearson's correlation coefficient. An ANOV A was then used to control for the effects of age and BMI on the inter-group differences in questionnaire scores. The distribution of the BITE severity score was not normal even after logarithmic transformation, and, therefore, groups were compared by nonparametric methods. Bonferroni's correction was applied to significance levels to account for the effects of applying multiple tests to one population of subjects. In this correction, the desired significance value is divided by the number of tests to reach a final significance value. 12 RESULTS

Three hundred seventy-five women were offered the questionnaire, and ofthese 342 (91 %) agreed to complete it. One hundred fifty-two patients were classified as having polycystic ovaries, 109 as having an organic endocrinopathy, (mixed organic diagnoses 28, prolactinoma 19; hyperprolactinaemia-no adenoma 14, premature ovarian failure 13, hypothalamic hypogonadotropins 8, hyperthyroid 4, hypopituitary 3, and hypothyroid 3. There 288

McCluskey et al.

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were one or two cases of each of the following: Turner's syndrome, congenital adrenal hyperplasia, non functioning adenoma, craniopharyngioma, ovarian cyst, multinodular goitre, temporal lobe epilepsy, endometriosis, gonadal dysgenesis, menopausal, hyperparathyroidism, alpha hydroxylase deficiency, and acromegaly). Eighty patients did not fulfill the criteria for either group. This latter group of patients had the following diagnosis: mixed organic and polycystic ovarian syndrome 32, weight or exercise-related amenorrhoea 13, obesity 1, hyperglycemia 1, premenstrual tension 5, depression 1, migraine 1, eczema 1, and recurrent miscarriage 1. In addition, 3 patients were found to have no pathology, and in 22 patients the diagnosis could not be reached. A study was made ofthe nonresponders, and the distribution of patients with either PCOS or organic endocrinopathy did not vary from those patients included in the study (x 2 = 0.87, P > 0.05). Table 1 illustrates the age, BMI, and BITE scores by endocrinologic diagnostic groups. The patients with PCOS had a significantly higher mean BITE score than those in the organic group. There was no significant difference in the mean BMI between the groups, but the organic group was significantly older than the group with polycystic ovaries. Age was found to be negatively correlated with the BITE symptom score (r = -0.19, P = 0.001), whereas BMI was found to be positively correlated with the score (r = 0.2, P < 0.01). An ANOV A was therefore carried out controlling for age and BMI, and this continued to demonstrate a highly significant difference between the two groups with higher BITE scores still being observed in women suffering from PCOS (F = 14.2, df = 1238, P < 0.001). Figure 1 demonstrates the BITE scores in each group, and Table 2 is a categorical analysis of the BITE score, demonstrating that approximately 6% of women in the polycystic ovarian group as compared with 1 % of women in the group with organic endocrinopathies (as defined in methods) achieve the Diagnostic and Statistical Manual of Mental Disorders, 3rd edition, diagnostic criteria of bulimia3 (95% confidence interval (CI) for the difference between proportions are 3 % and 7%). Overall, one third of women with polycystic ovaries had abnormal BITE scores (Table 2) as opposed to 14% of patients with an organic endocrinopathy (95% CI for the difference between proportions are 12% and 23%). Table 3 is an analysis of the behavioral components ofthe BITE severity score and demonstrates Fertility and Sterility

Table 1

An ANOV A of Age, BMI, and BITE Scores Between Groups

Organic group Polycystic ovary group 95% Cl b

Fratio Probability a

Age

BMI

BITE symptom score

109 (32.3 ± 8.4)a 153 (27.5 ± 6.4) +3.0 to +6.6 24.42 <0.001

99 (25.4 ± 5.4) 143 (24.4 ± 5.1) -0.3 to +2.3 1.78 0.18

109 (5.2 ± 4.5) 153 (7.8 ± 6.1) -3.9to-1.2 12.68 <0.001

Values are numbers with means ± SD in parentheses.

that although binge eating and fasting are significantly more common in women suffering from peos, there is not a difference in the incidence of vomiting or abuse of laxatives, diuretics, or diet pills. DISCUSSION

These results demonstrate an association between abnormal eating behavior and peos. Patients with polycystic ovaries were six times more likely to have a high BITE score and twice as likely to have subclinical bulimia as demonstrated by a medium score. When specific symptoms were considered, a positive relationship was found between both binge eating and fasting and the diagnosis of

peos. Possible explanations for the association between peos and abnormal eating behaviors are as follows. Both disorders are relatively common in the female population so they may coexist by pure chance. Polycystic ovarian syndrome, as diagnosed from US criteria,lO is a heterogeneous collection of disorders and include people of below average weight, average weight, and above average weight. 2 BITE SYMPTOM SCORES IN 20

§'

Polycystic Ovary Syndrome Group.

" ::>

18

;;

[6

~

14

'";;s:;:

12

~

10

"' ~

8

6

6

>~

4

Organic Group

o

is

o

1----*

0

b

CI, confidence interval.

It has been shown to occur in about 26 % of a volunteer population. 6 Bulimia nervosa occurs in about 2% of the adult female population,3 whereas binge eating may occur in as much as 21 % of women. 7 We initially speculated that women with an endocrinopathy that disturbs their menstrual cycle may be predisposed to the development of abnormal eating patterns. However, the finding that women with organic endocrinopathies have an incidence of abnormal eating behavior that is very similar to the general population suggests that the presence of an endocrinopathy in itself is not a predisposing factor to abnormal eating behavior. In peos, menstrual irregularities, together with hirsutism, above average weight, and anxieties about fertility are in direct conflict with socially accepted normal views of femininity. These may well lead to abuse of food as a means of coping with the resultant emotional distress. A third explanation is that women who are genetically predisposed to develop polycystic ovaries may do so in the environment of binge eating followed by intermittent fasting. Abnormal insulin secretion has been observed to occur in forced starvation 13 as well as in the voluntary starvation that accompanies anorexia nervosaY Recently, a disturbed insulin response has been reported in association with bulimia. 15 Insulin resistance is well described in patients with polycystic ovaries 16,17 and may occur at any body weight. It is postulated, therefore, that patients with a genetic predisposi-

ABNORMAL SCORES

Table 2 Class of BITE Symptom Scores Compared Between Groupsa,b

1;;

"'::>@' g;

2

Organic group o

1 2

3

4

5

6

7

8

9 10 J 1 12 13 \4 15 16 17 18 19 20 21 22 23 24 25

BITE SYMPTOM SCORE

Figure 1 A comparison of the frequencies of BITE scores in PCOS and an organic control group. Vol. 55, No.2, February 1991

Polycystic ovary group a

b

Low score

Medium score

High score

94 (86)

14 (13)

1 (1)

105 (69)

38 (25)

10 (6)

Values in parentheses are percents. X2 = 12.0; P = 0.002,

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r

BULIMIA INYESTIGTION TEST EDINBURGH. (BITE) PADENTNAME _ _ _ 1. 2. 3.

...

5. ~

-.-----..DAIE --'--'_

M _ _ , . - - - - - - . - - - - . -. .

Do you have • replar daiJ)' eatiDa pattern? Are you • strict dieter?

yes/DO yes/DO yes/DO

Do you feel a faUure If you break your diet Just once? Do you count the calories of evel')'lbiD& you eat.

even when not on a diet?

yes/no

Do you ever f.st for a whole day? -if yes, bow often 15 tbls?

yes/DO

every second da1 2-3 times • week once.week nowandtbeD

have once

.,

Do you do 1liiy of the foUowing to belp you lose weIPt?

(tick

)

never

Take diet pUIs Take diuretics Take Iax.tlves Make yourself vomit

0 0 0 0

occaslonally

once

2 2 2 2

3 3 3 3

2-3 times • week

26.

Does your pattem of eatiDa severely disrupt your ore? Would you say that food dominated your ore? Do you ever e.t IIIId eat until you are stopped by pbyslcal discomfort? Are there times when aU you can tbink about is food? Do you eat sensibly In front of others IIIId make up In private? CIIII you always stop eatiDa when you Wllllt to? Do you ever experience overpowering urges to eat IIIId eat IIIId eat? When you anxious do you tend to eat a lot? Does the thought of being fat terrify you? Do you ever eat large amounts offood rapidly (not a meal)? Are you asbamed of your eating babits? Do you worry that you bave no control over bow much you eat? Do you tum to food for comfort? Are you able to leave food on the plate at tbe end of a meal? Do you deceive otber people about bow much you eat? Does bow bungry you feel determine bow much you eat? Do you ever binge on large amounts of food? -if yes, do such binges leave you feeling miserable? If you do binge, 15 this only when you are alone?

fYJ.7

If you do binge, bow often 15 this?

8. 9. 10. H. U. 13. 14.

15. 16.

17. 18. 19. 20. 21. 22.

23. 24. 25.

4 4 4 4

daiJ)'

5 5 5 5

5+

2-3 times

dJDes

.da1

.da1

6 6 6 6

7 7 7 6 yes/no yes/DO yes/DO yes/no yes/no yes/no yeslno yes/no yes/DO yeS/DO yes/no yes/no yes/ no yes/no yeS/DO yeS/DO yes/no yes/DO yes/DO

IIardIf ever once • IIIOIdIa once • week 2-3 times."'" dally 2-3 times • da1

28. 29. 30.

31. 32. 33.

Would you 10 to areat lengths to satisfy l1li urge to binge? If you overeat do you feel very auBty? Do you ever eat In secret? Are your eatiDa habits what you would consider to be normal? Would you consider yourself to be a compUlsive eater? Does your welPt Ructuale by more than 5 pounds a week? Figure 2

290

McCluskey et al,

yes/no yes/DO yeS/DIO yes/DIO yes/DO yes/DIO

The Bulimia Investigation Test, Edinburgh, (BITE). (*, See Appendix.)

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Fertility and Sterility

Table 3 Behavioral Components of BITE Severity Score Analyzed

Diuretic abuse Laxative abuse Vomiting Diet pill abuse Binge eating Fasting

Probability

Significance

Bonferroni corrected significance

0.367 0.257 0.234 0.037 0.003 0.001

NS· NS NS S S S

NS NS NS NS S S

• NS, not significant.

tion to peos who are subject to wild fluctuations in carbohydrate intake may well become mildly insulin resistant and that this may facilitate the development of polycystic ovaries. In conclusion, we have demonstrated a clear association between polycystic ovaries and abnormal eating behaviors including clinical bulimia. 3 The treatment of bulimia is highly successful,5 and it may well be that patients with polycystic ovaries should be screened both for bulimia nervosa and subclinical eating disorders. Those with high scores should receive eating behavioral treatment as an adjuvant to standard therapy. APPENDIX

The BITE questionnaire* is given in Figure 2. The symptom scale consists of all questions except the three marked with an asterisk. Questions 1, 13, 21, 23, and 31 score one point for a response of "No," whereas the remaining questions score one point for a response of "Yes," giving a total of 30 points. The questions (6, 7, and 27) marked with an asterisk make up the severity scale, and the total score is the sum of the numbers corresponding to the circled responses. See text for the interpretation ofthe results. The questionnaire has been validated on a population of 1,333 women and men and has a sensitivity of 100%, specificity of 95%, and a positive predictive value of 89% with a false positive rate of 5%.

* From Freeman and Henderson. 9 Reproduced with the permission of the publisher.

Vol. 55, No.2, February 1991

Acknowledgment. The authors are grateful to Christopher Freeman, M.R.C.Psych., Department of Psychiatry, University of Edinburgh, Edinburgh, Scotland, for permission to reproduce the BITE questionnaire and for the validation results.

REFERENCES 1. Treasure JL, Gordon PAL, King EA, Wheeler M, Russel GFM: Cystic ovaries: a phase of anorexia nervosa. Lancet 2:1379,1985 2. Conway G W, Honour JW, Jacobs HS: Heterogeneity of the polycystic ovary syndrome endocrine and ultrasound features in 556 patients. Clin Endocrinol (Oxf) 30:459, 1989 3. American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders, 3rd edition. Washington, D.C., American Psychiatric Association, 1980 4. Fairburn CG, Cooper PJ: The clinical features of bulimia nervosa. Br J Psychiatry 144:283, 1984 5. Lacey JH: The bulimic syndrome at normal body weight: reflections on pathogenesis and clinical features. Int J Eating Disord 2:59, 1982 6. Polson DW, Wadsworth J, Adams J, Franks S: Polycystic ovaries: a common finding in normal women. Lancet 1:871, 1988 7. Cooper PJ, Fairburn CG: Binge-eating and self induced vomiting in the community, a preliminary survey. Br J Psychiatry 142:139, 1983 8. Henderson M, Freeman CPL: A self-rating scale for bulimia: the 'BITE'. Br J Psychiatry 150:18, 1987 9. Freeman CPL, Henderson M: The 'BITE': indices of agreement. Br J Psychiatry 152:575, 1988 10. Adams J, Polson DW, Abdulwahid N, Morris DV, Franks S, Mason HD, Tucker M, Price J, Jacobs HS: Multifollicular ovaries: clinical and endocrine features and response to pulsatile gonadotrophin releasing hormone. Lancet 2:9469, 1985 11. Garrow JS, Webster J: Quetelet index (W /H2 ) Int JObes 9:147,1985 12. Grove WM, Andreasen NC: Simultaneous tests of many hypotheses in exploratory research. J Nerv Ment Dis 170: 3, 1982 13. Crisp AH, Ellis J, Lowy C: Insulin response to a rapid intravenous injection of dextrose in patients with anorexia nervosa and obesity. Postgrad Med J 43:97, 1967 14. Unger RH, Eisentraut AM, Madison L: The effects oftotal starvation upon the levels of circulating glucagon and insulin in man. J Clin Invest 42:1031,1963 15. Schweiger U, Poellinger J, Laessle R, Wolfram G, Fichter MM, Pirke K: Altered insulin response to a balanced test meal in bulimic patients. Int J Eating Disord 6:551, 1987 16. Prelevic GM, Wurzburger MI, Peric LA: Pancreatic beta cell function in polycystic ovary syndrome: its relationship to body weight, serum testosterone and serum prolactin levels. Exp Clin Endrocrinol 90:76, 1987 17. Chang RJ, Nakamura RM, Judd HJ, Kaplan SA: Insulin resistance in nonobese patients with polycystic ovary disease. J Clin Endrocrinol Metab 57:365, 1983

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