British Journal of Psychiatry (1992), 161, 671-674
Differential Rates of Psychiatric Disorders in Adults with Down's Syndrome Compared with Other Mentally Handicapped Adults RICHARD A. COLLACOTT, SALLY-ANN COOPER and CATHERINE McGROTHER
The total number of adults with Down's syndromeliving in Leicestershire,ascertainedby widespreadenquiry,wasfoundto be378. Ofthese,371 werematchedwith adultswith mental handicapdue to other pathologies,on the basisof age, sex, and type of residence.Those with Down's syndromewere found to have a different spectrumof mental disordersfrom those without the syndrome.In particular,Down's syndromepatients were more likely to have been diagnosedas havingdepressionand dementia;the controlswere more likely to have been diagnosed as suffering from conduct disorder, personality disorder, or schizophrenia/paranoid state. The sameproportionof each grouphadbeengivena diagnosis of autism. Psychiatric
by medical staff who attend each day centre managed by
disorders are more frequent among the
LeicestershireSocial Services.
mentally handicapped than in the general population
Individuals with Down's syndrome were matched on the
(Rutter et a!, 1970; Richardson et a!, 1979). In addition, it is generally considered that certain forms
basis of age (to within one year), sex, and residential placementwith controls who were mentally handicapped as a result of aetiological processes other than Down's syndrome. Suitable controls were ascertained using the
of primary mental handicap may predispose to the development of particular mental disorders. The clearest associations that have been established between a syndromal cause of mental handicap and mental illness concern Down's syndrome. Those with Down's syndrome are particularly vulnerable to hypothyroidism and its associated mental disorders.
Leicestershire mental handicap register. The case recordsof all those with Down's syndromeand their matching controls that were available to the mental handicap psychiatric services were scrutinised. Data extractedfrom the case recordsincludedinformation
concerning a past history of formal psychiatric interview,
The association between Down's syndrome and a presenile dementia of the Alzheimer type is well established. Malamud's (1964) finding that 100% of
clinical features of mental disorders, and psychiatric diagnoses. Psychiatric diagnoses were detessniised according
to information available in the psychiatric records, and
Down's syndrome individuals who died over the age of 40 years had histopathological evidence of Alzheimer's disease has been confirmed by other
retrospectively classified according to ICD-9 criteria (World
Health Organization, 1978). In the case of depressive disorders, stratification into either manic—depressive psychosis, depressed type, or neurotic depression cannot be made with confidence in the mentally handicapped population. Accordingly, both depressive types were collapsed into a single diagnostic grouping. Similarly, difficulty is experienced in diagnosing schizophrenia and
workers (Haberland, 1969; Whalley, 1982). Apart from hypothyroidism and Alzheimer's disease,
the vulnerability
of people with Down's
syndrome to other psychiatric disorders appears to be relatively unexplored. However, Down's syndrome has been considered to protect against hypomania (Sovner et a!, 1985), although others dispute this (Cook & Leventhal, 1987; McLaughlin, 1987). We therefore undertook to examine the pattern of psychiatric morbidity in a group of adults with Down's syndrome, compared with that in a group of controls without Down's syndrome. Method
The population of adults with Down's syndrome in Leicestershire was ascertained by inspection of Health Service
records,
information
contained
on the Leicestershire
mental handicap register (a joint National Health Service and Social Servicesventure), and from information supplied
paranoid states as separate groups with confidence; therefore thesetwo groups have been amalgamatedinto a single category.
Recorded
psychiatric
diagnosis and other
data were transferredto an Amstrad 2086 computer. Data
wereprocessedusingthe SYSTAT statisticalprogram, using Students'
t-test, x2 test, and Pearson
probabilities.
Resufts
The total population served by Leicestershire Health Authority is approximately890000, out of which a total of 378adultswithDown'ssyndromewasidentified.Review wasundertaken of 371of theseadults (98.l°lo), and it was possible to undertake a close match with 371 mentally handicappedcontrolswithoutDown'ssyndrome.The mean (s.d.) ageof thosewithDown'ssyndromewas36.34(11.25)
671
672
COLLACOT@ET AL
years.The meanage of the controlswas36.32(11.18)years (t=0.029, P=0.976). The range of ages was 16 years to 78 years. Fifty-three per cent of both groups were male. Forty-three (11.6%) Down's syndrome patients and 46 (12.4%)controlsresidedwithinthe hospitalfacilitiesof the Glenfrith Unit; all others resided in the community (@=0.l2, d.f. =1, NS). The hospital patients (mean age 44.8 (12.4) years) were older than those living in the community (mean age 35.1 (10.6) years) (t=7.940, P
Differential Rates of Psychiatric Disorders in Adults with Down's Syndrome Compared with Other Mentally Handicapped Adults RICHARD A. COLLACOTT, SALLY-ANN COOPER and CATHERINE McGROTHER
The total number of adults with Down's syndromeliving in Leicestershire,ascertainedby widespreadenquiry,wasfoundto be378. Ofthese,371 werematchedwith adultswith mental handicapdue to other pathologies,on the basisof age, sex, and type of residence.Those with Down's syndromewere found to have a different spectrumof mental disordersfrom those without the syndrome.In particular,Down's syndromepatients were more likely to have been diagnosedas havingdepressionand dementia;the controlswere more likely to have been diagnosed as suffering from conduct disorder, personality disorder, or schizophrenia/paranoid state. The sameproportionof each grouphadbeengivena diagnosis of autism. Psychiatric
by medical staff who attend each day centre managed by
disorders are more frequent among the
LeicestershireSocial Services.
mentally handicapped than in the general population
Individuals with Down's syndrome were matched on the
(Rutter et a!, 1970; Richardson et a!, 1979). In addition, it is generally considered that certain forms
basis of age (to within one year), sex, and residential placementwith controls who were mentally handicapped as a result of aetiological processes other than Down's syndrome. Suitable controls were ascertained using the
of primary mental handicap may predispose to the development of particular mental disorders. The clearest associations that have been established between a syndromal cause of mental handicap and mental illness concern Down's syndrome. Those with Down's syndrome are particularly vulnerable to hypothyroidism and its associated mental disorders.
Leicestershire mental handicap register. The case recordsof all those with Down's syndromeand their matching controls that were available to the mental handicap psychiatric services were scrutinised. Data extractedfrom the case recordsincludedinformation
concerning a past history of formal psychiatric interview,
The association between Down's syndrome and a presenile dementia of the Alzheimer type is well established. Malamud's (1964) finding that 100% of
clinical features of mental disorders, and psychiatric diagnoses. Psychiatric diagnoses were detessniised according
to information available in the psychiatric records, and
Down's syndrome individuals who died over the age of 40 years had histopathological evidence of Alzheimer's disease has been confirmed by other
retrospectively classified according to ICD-9 criteria (World
Health Organization, 1978). In the case of depressive disorders, stratification into either manic—depressive psychosis, depressed type, or neurotic depression cannot be made with confidence in the mentally handicapped population. Accordingly, both depressive types were collapsed into a single diagnostic grouping. Similarly, difficulty is experienced in diagnosing schizophrenia and
workers (Haberland, 1969; Whalley, 1982). Apart from hypothyroidism and Alzheimer's disease,
the vulnerability
of people with Down's
syndrome to other psychiatric disorders appears to be relatively unexplored. However, Down's syndrome has been considered to protect against hypomania (Sovner et a!, 1985), although others dispute this (Cook & Leventhal, 1987; McLaughlin, 1987). We therefore undertook to examine the pattern of psychiatric morbidity in a group of adults with Down's syndrome, compared with that in a group of controls without Down's syndrome. Method
The population of adults with Down's syndrome in Leicestershire was ascertained by inspection of Health Service
records,
information
contained
on the Leicestershire
mental handicap register (a joint National Health Service and Social Servicesventure), and from information supplied
paranoid states as separate groups with confidence; therefore thesetwo groups have been amalgamatedinto a single category.
Recorded
psychiatric
diagnosis and other
data were transferredto an Amstrad 2086 computer. Data
wereprocessedusingthe SYSTAT statisticalprogram, using Students'
t-test, x2 test, and Pearson
probabilities.
Resufts
The total population served by Leicestershire Health Authority is approximately890000, out of which a total of 378adultswithDown'ssyndromewasidentified.Review wasundertaken of 371of theseadults (98.l°lo), and it was possible to undertake a close match with 371 mentally handicappedcontrolswithoutDown'ssyndrome.The mean (s.d.) ageof thosewithDown'ssyndromewas36.34(11.25)
671
672
COLLACOT@ET AL
years.The meanage of the controlswas36.32(11.18)years (t=0.029, P=0.976). The range of ages was 16 years to 78 years. Fifty-three per cent of both groups were male. Forty-three (11.6%) Down's syndrome patients and 46 (12.4%)controlsresidedwithinthe hospitalfacilitiesof the Glenfrith Unit; all others resided in the community (@=0.l2, d.f. =1, NS). The hospital patients (mean age 44.8 (12.4) years) were older than those living in the community (mean age 35.1 (10.6) years) (t=7.940, P
