Epilrpsiu, 33(4):657460, 1992 Raven Press, Ltd., New York 0 International League Against Epilepsy

Epileptic Seizures in Elderly Patients with Dementia Martin J. McAreavey, Brian R. Ballinger, and George W. Fenton Department of Psychiatry, University of Dundee, Scotland

Summary: All inpatients aged >55 years with dementia in the Dundee Psychiatric Service were surveyed for seizure occurrence by interviewing staff and reviewing records. Of 208 patients, 19 (9.1%) were recorded as having seizures. The seizures were major in 92% and occurred at a rate of -2.3 seizures per patient per year. Patients with epilepsy were significantly younger than a control group of dementia inpatients and were significantly more cog-

nitively impaired on the survey Clifton Assessment Procedure for the Elderly (CAPE), but not on the Mini Mental State Examination. Of 11 1 reported accidents, only 5 appeared to be associated with epilepsy. Although epileptic seizures are relatively common in patients with severe dementia, they rarely caused severe problems. Key Words: Epilepsy-Seizures-Aged-Dementia.

Epileptic seizures have been reported to occur frequently in the general elderly population (Sung and Chu, 1990). There are fewer reports of seizures in elderly people with dementia, but Hauser et al. (1986) reported a greater prevalence in this group than in a control group matched for age. Estimates of the prevalence of epilepsy in the Alzheimer type of dementia have varied, with Sjogren et al. (1952) reporting 22%, Hauser et al. (1986) reporting lo%, and Pearce and Miller (1973) reporting 16%. Sourander and Sjogren (1970) suggested that in persons with senile dementia of the Alzheimer type, generalized convulsions tended to occur during the last 6 months of life, whereas minor epileptic attacks appeared comparatively early in the course of the disease. Epilepsy in the elderly has been reported to occur in a variety of ways (Godfrey, 1989). Important etiologic factors in the general elderly population include cerebrovascular disease, head injury, and tumors (Roberts et al., 1982; Luhdorf et al., 1986; Sung and Chu, 1990). Another cause of seizures may be ingestion of certain types of psychotropic drugs (Toone and Fenton, 1977), although how important a factor this is in individuals with dementia is uncertain. We assessed the characteristics and prevalence of epileptic seizures in a population of

elderly inpatients with dementia and investigated possible associated factors. METHODS

Subjects The inpatient population of the Dundee Psychiatric Service was surveyed in November 1989. Dementia was diagnosed in 208 patients aged >55 years by the responsible consultant psychiatrist using ICD 9 criteria. The patients were drawn from a catchment population of 180,000 and were likely to include those with more severe dementia and associated behavior disturbance necessitating inpatient management. Epileptic seizures were defined as brief and usually unprovoked stereotyped disturbances of behavior, emotion, motor function, or sensation which on clinical evidence were believed to result from an abnormal cortical neuronal electrical discharge. Patients were identified through a review of all prescription sheets for antiepileptic drug (AED) prescriptions, and ward nursing and medical staff were also asked about the occurrence of epileptic attacks in their inpatient populations. The case records were then checked to confirm the diagnosis and ascertain the reasons for prescription of any AEDs. Patients were included if epileptic seizure occurrence had been diagnosed by the doctor in charge of the ward and the diagnosis was confirmed by the authors. Seizures were classified as (a) major seizures, generalized tonic-clonic; and (b) minor seizures,

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Received March 1991; revision accepted November 1991. Address correspondence and reprint requests to Dr. B. R. Ballinger at Royal Dundee Liff Hospital, Liff by Dundee, DD2 5NF, Scotland.

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nonconvulsive seizures of all types in the International Classification (Commission, 1981). Because we could not separate absence and partial seizures reliably from the clinical evidence, we included both in the minor seizure group. The subjects diagnosed as having dementia and seizures were assessed by (a) present cognitive function by interviews using the survey version of the Clifton Procedure for the Elderly (CAPE) (Pattie, 1981) and the Mini Mental State Examination (Folstein et al., 1975) and (b) by perusing the psychiatric notes to obtain information about diagnosis, age, and physical health, including abnormal neurologic signs on routine physical examination, dates of admission, medical history, previous mental state, accidents recorded on standard forms by ward staff, and relevant investigations. All patients had routine hematologic and biochemical screening, but computed tomography (CT) scans were performed only on younger patients or in patients with a suggestion of focal cerebml lesions. Detailed information about the seizures was obtained from medical and nursing records, and the prescription sheets were reviewed for information about AED and other drug use at the time of the seizures. Control groups A control group (A) was selected from all patients resident in the same ward, matched for sex and diagnosis of dementia only, using random number tables. A further control group (B) matched for age, sex, length of stay, type of dementia, and survey CAPE score was selected from the same wards in a similar fashion to enable a comparison of drug treatments. Drug treatment was studied for the month preceding each seizure and for the corresponding period in the control groups. These control groups were then assessed in the same way as the seizure group. For the control group, a comparable date in terms of months and years since admission was selected to match each of the dates of the seizures recorded in the seizure group. The statistical methods used were the two-tailed t test, the MannWhitney test, and the chi-square test. RESULTS Seizures Of 208 inpatients, 19 (9.1%) with dementia were diagnosed as having epileptic seizures. The total number of recorded seizures during the inpatient stay was 82; 59 (72%) were classified as ‘‘major’’ and 18 as “minor.” Five could not be classified. Nine individuals had both major and minor seizures, 6 had major seizures only, 3 had minor sei-

Epilep.tiu, Vol. 33, N o . 4, 1992

zures only, and only 1 patient had unclassifiable seizures. The rate of seizures per patient since the first recorded seizure was 2.3 seizures per year per patient, with a mean time since onset of the seizure disorder of 1.86 years. None of the seizures was definitely provoked by other illness. The first epileptic seizure occurred at a mean time of 2.7 years after admission, when the average age of the population was 74.4 years (range 58.3 to 87.8 years). The type of first recorded seizure was major in 12 cases, minor in 3, and unclassifiable in 4. Only 1 patient had an epileptic seizure recorded before being admitted to hospital. Myoclonic jerking was also noted apart from the seizures in 7 patients in the seizure group, occurring at a mean rate of 9.73 episodes per year after admission for each patient. Comparison between the dementia seizure group and the overall dementia inpatient population Three of 40 (7.5%) men and 16 of 168 (9.5%) women with dementia had had seizures. Sixteen (84%) of the seizuddementia group had a diagnosis of senile dementia of the Alzheimer type, whereas 168 (81%) of the entire population had this diagnosis. Three (16%) seizutddernentia patients were diagnosed as having multiinfarct dementia as compared with 37 (18%) of the entire population (3 patients had other forms of dementia). Comparison with control group A (matched for sex and diagnosis of dementia only) The mean age of the seizure/dementia group was significantly lower than that of the controls (Table 1) both at the time of the survey and at the time of admission to hospital. The seizure group had been TABLE 1. Some characteristics o f seizure group and control group A Parameter Mean age (yrj Range (yr) Age on admission to hospital Range (yr) Mean length of stay Range (yr) Mean CAPE I/O score Range Mean physical disability score on CAPE Range

Seizure group

Control group A

76.3 (SD 58.1-88.6

+ 7.8)”

84.4 (SD 60.8-94.5

72.2 (SD 53.2-85.5 4.1“ 0.25-12.2

+ 8.12)’

0-4

82.0 (SD + 8.1)’ 57.3-94 .x 2.4‘ 0.14.2 2.1d 0-9

8.7‘ 1-12

5.4‘ 5.11

0.@

CAPE, Clifton Assessment Procedure for the Elderly. t Test, p < 0.01. t Test, p < 0.02. ‘ Mann-Whitney test, NS. Mann-Whitney test, p < 0.05.

+ 7.9)“

EPILEPSY I N ELDERLY DEMENTIA PATIENTS in the hospital longer, but this difference was not statistically significant. A significant difference was noted in the informationlorientation part of the CAPE at the time of interview (Table I), although the difference at time of admission was not statistically significant (mean score 3 . 3 in the seizure group and 4.7 in the control group). The Mini Mental State scores at the time of assessment, although lower in the seizure group (mean 2.5, range 0-12) than in controls (mean 4.8, range 0-24), were not significantly different, however. The physical disability section of the CAPE did not differ significantly in the two groups; in particular, there was no significant difference in the walking component. Only 3 seizure patients had CT scans, and all showed cortical atrophy. The two CT scans performed on controls showed cortical atrophy and ventricular dilatation, respectively. The seizure group had an average of 1.43 accidents per year of long-term admission as compared with 1.53 per year for controls. Of the 1 1 1 reported accidents in the seizure group, 92% were falls. Five were recorded as being associated with epileptic seizures; none resulted in serious injury. Comparison between seizure group and control group B It was possible to match only 13 of the seizure group for the variables of sex, age, type of dementia, Clifton information/orientation, and length of stay of control group B. Eleven of the 13 matched seizure patients were receiving neuroleptic medication at the time of the epilepsy as compared with 9 of the control group. The seizure group patients were receiving a mean dose of 92.7 mg/day of thioridazine or equivalent, as opposed to a dose of 54.1 mg/day in the control group. Use of other psychotropic drugs was too limited for us to reach any conclusions about individual drugs. When the number of psychotropic drug changes made in the month before the seizure was compared with an equivalent period in the control group, there were 10 changes in the seizure group as compared with three in the controls (x2 = 4.77, df = 1 , p < 0.05). AED medication in the seizure group Only 8 seizure patients and no controls were receiving AEDs: phenytoin (4), carbamazepine (2), and phenobarbital (2). At the time this study was performing, starting AED treatment after the first seizure was not usual. The numbers were too small to make any firm conclusions about efficacy, although all patients continued to have seizures.

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DISCUSSION This was a limited study, and relatively few individuals with seizures were studied. The selected control groups were similarly limited in number. The dementia population surveyed consisted of a selected group of individuals with more severe dementias and, often, behavior disturbances requiring psychiatric care. Therefore, these findings may not necessarily apply to other patients with less severe dementia. Another drawback was the limited description of some of the seizures; in addition, the survey was partly retrospective. The patients were included if the diagnosis of seizure occurrence was reasonably firmly established according to our criteria, however. The prevalence of seizures in this dementia population is relatively high at 9.1%, a prevalence similar to that reported by Hauser et al. (1984) although somewhat lower than that of some other reports (Sjogren et al., 1952; Pearce and Miller, 1973). Most (72%) of the seizures were classified as major, in keeping with results of other surveys, apart from the report by Sjogren et al. (1952), who reported a preponderance of minor attacks. Seizures were relatively infrequent, with 2.3 episodes per year per patient, although this was probably modified by the AED treatment received by some patients. Because the patients were under close observation in the ward, many of their seizures were probably observed by the staff. None of the patients had major seizures occurring more often than monthly, and it had been believed necessary to initiate AED therapy in only 8 patients, usually after occurrence of about three seizures in a I-year period. The patients with epilepsy did not differ greatly from the hospital dementia population in terms of sex and type of illness, since there was a considerable preponderance of women with the Alzheimer type of dementia. The diagnoses of all the patients were made on clinical grounds, and some diagnosed as having Alzheimer type of dementia may have had other etiologies. The mean age of the seizure group was lower than that of controls; the significance of this is not clear, although Hauser et al. (1984) suggested that epilepsy may define a unique subgroup. Some findings suggested that the dementia of the seizure group was more severe than that of the rest of the inpatient population, although this may represent a different stage of the dementing process. The higher mean neuroleptic dose of the seizure group raises the possibility that these drugs contrib-

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uted to the seizures. The behavioral features of the seizure group also may have differed from those of the controls, necessitating use of a larger dose of neuroleptic drugs ; because information was insufficient, we could not reach any firm conclusion about this. Epileptic seizures are common in patients with relatively severe dementia but do not usually recur frequently and rarely cause death or major injuries. A fuller definition of the clinical phenomenon, its natural history, and prognostic significance is necessary. Clearer guidelines about treatment are required. Acknowledgment: We thank t h e medical and nursing staff in the D u n d e e Psychiatric Service f o r their cooperation.

Toone BK, Fenton GW. Epileptic seizures included by psychotropic drugs. Psychol Med 1977;7:265-70.

&SUME Tous les patients BgCs de plus de 55 ans prtsentant une demence et hospitalises dans le service de psychiatrie de Dundee ont it6 CtudiCs afin d’tvaluer la survenue de crises, par interrogation du personnel soignant et examen des dossiers medicaux. Sur 208 patients, 19 (9.1%) avaient prCsente des crises. Les crises Cttiient importantes chez 92% et survenaient a une frequence rnoyenne d’environ 2.3 crises par patient et par annee. Les pdtients presentant des crises Ctaient significativement plus jeunes qu’un groupe contrble de patients dements hospitalises, et prCsentaient une alteration des fonctions cognitives significativement plus importante au test CAPE, mais non I’examen du Mini Mental State. Sur 11 1 accidents repertoit-&, 5 seulement semblaient avoir e t C associts a des crises epileptiques. Les auteurs concluent que les crises Cpileptiques sont relativement frequentes chez les patients presentant une dkmence severe, mais qu’elles sont rarement responsables de problemes graves. (P. Genton, Marseille)

REFERENCES Sung C-Y, Chu N-S. Epileptic seizures in elderly people: aetiology and seizure type. Age Ageing 1990;19:25-30. Commission on Classification and Terminology of the International League Against Epilepsy. Proposal for revised clinical and electroencephalographic classification of epileptic seizures. Epilepsia 1981;22:489-501. Folstein MF, Folstein SE, McHugh PR. Mini-Mental State. A practical method for grading the cognitive state of patients for the clinician. J Psychiat Res 1975;12:189-98. Godfrey JBW. Misleading presentation of epilepsy in elderly people. Age Ageing 1989;18: 17-20. Hauser WA, Morris ML, Jacobs MP, Heston LL, Anderson VE. Unprovoked seizures in patients with Alzheimers disease. Epilepsia 1984;2S:658. Hauser WA, Morris ML, Heston LL, Anderson VE. Seizures and myoclonus in patients with Alzheimers disease. Neurology 1986;36:122630. Luhdorf K , Jensen LK, Plesner AM. Etiology of seizures in the elderly. Epileppsia 1986;27:45843. Pattie AH. A survey version of the Clifton Assessment Procedure for the Elderly (CAPE). Br J Clin Psychol 1981;20:17380. Pearce J, Miller E. Clinical aspects of dementia. London: Bailliere Tindall, 1973. Roberts MA, Godfrey JW, Caird F1. Epileptic seizures in the elderly: 1. Aetiology and type of seizure. Age Ageing 1982; 11:24-8. Sjogren T, Sjogren H, Lindgren AGH. Morbus Alzheimer and Morbus Pick: a genetic, clinical and pathodnatomical study. Acta Psychiatr Neurol Scand 1952;suppl 82:75-93. Sourander P, Sjogren H. The concept of Alzheimer’s disease and its clinical implications. In: Wolstenholme GEW, O’Connor M, eds. Alzheimer’s disease and related conditions. London: Churchill, 1970.

Epilepsia, Vul. 33, N o . 4, 1992

RESUMEN Revisando las historias y entrevistando a 10s asistentes hospitalarios todos 10s pacientes hospitalizddos mayores de 55 anos de edad y que padecian demencia han sido estudiados en el Servicio de Psiquiatria Dundee. De 208 pacientes, 19 (9. I%) habian padecido ataques. Los ataques fueron generalizados en el 92% y ocurrieron en una frecuencid de, aproximadamente, 2.3 ataques por paciente por ano. Los pacientes con epilepsia fueron significativamente mas jovenes que el grupo control de enfermos con demencia y mostraron una mayor afectacion cognitiva en el Test CAPE pero no utilizando el Test Mini Mental. Se registraron I 1 1 accidentes pero, solamente 5 estuvieron asociados a ataques. A pesar de que 10s ataques epilepticos son relativamente cornunes en enfermos con demencia severa raramente causan problemas severos. (A. Portera-Sanchez, Madrid)

ZUSAMMENFASSUNG Im psychiatrischen Langzeitbereich in Dundee wurden alle Patienten uber 55 Jahre mit einer Demenz auf Anfalle hin untersucht durch Mitarbeiterbefragung und Sichtung der Krankenakten. Von 208 Patienten hatten 19 Anfalle (9.1%). In 92% traten groBe Anfalle auf. Die Haufigkeit lag bei 2.3 Anfalle pro Jahr. Patienten mit einer Epilepsie waren signifikant jiinger als eine Kontrollgruppe von Patienten mit einer Demenz. Sie waren zwar kognitiv signifikant schlechter im CAPE-Test aber nicht in der Mini-Mental-State-Untersuchung. Von 11 1 Unfallen traten nur 5 ini Rahmen epileptischer Anfalle auf. Obwohl epileptische Anfalle bei Patienten rnit Demenz haufig sind, ergeben sich daraus keine schwerwiegenden Probleme. (C. G . Lipinski, HeidelhergiNeckarg.emiind)

Epileptic seizures in elderly patients with dementia.

All inpatients aged greater than 55 years with dementia in the Dundee Psychiatric Service were surveyed for seizure occurrence by interviewing staff a...
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