Scot Moo J 1992; 37: 181-184
0036-9330/92/06092/181 $2.00 in USA © 1992 Scottish Medical Journal
CREUTZFELDT-JAKOB DISEASE IN SCOTLAND AND NORTHERN IRELAND 1980.1989
T.G. Esmonde,R.G. Will Department of Clinical Neurosciences, Western General Hospital, Edinburgh Abstract: The epidemiological and clinical features of Creutzfeldt-Jakob disease have never before been studiedin Scotlandand Northern Ireland. Case recordsfor thosedyingwith thisdiagnosis wereobtainedfor theperiod1980-89. Over the tenyearperiod, 25 definite orprobable caseswereidentified, giving an annual incidence of 0.37cases/million. There weremore cases in the second half of the decade, and this was most likelydue to increased ascertainment. One pair of casesoccurredin closeproximity to each other. Sex distribution showedan excessofmales(male female ratio = 1.8 : 1). Mean age at onset was 65.2 years, and meanduration ofdisease was 5.3 months. Thepresenting symptoms and clinicalfeatures weresimilarto thosenotedin previousstudies ofotherpopulations. There was no excessofcases in occupations linkedto food.farming, or medical/paramedical work. Key words: Creutzfeldt-Jakob disease, spongiform encephalopathy, epidemiology, clinical features. Introduction reutzfeldt-JakOb disease (CJD) is a rare, fatal, rapidly progressive dementing illness with distinctive clinical features that was first recognised as a separate entity in 1921.1,2 There is no confirmatory in vivo diagnostic test, and the emergence ofbovine spongiform encephalopathy (BSE) in cattle, with the theoretical risk of transmission to man, has increased the importance of establishing the baseline epidemiological characteristics of CJD. The epidemiology of CJD in England and Wales has been the subject of previous research,3-6but similar studies have not been carried out in Scotland and Northern Ireland. The current paper forms part of a larger nationwide epidemiological survey of Creutzfeldt-Jakob disease comprising analysis of all cases occurring in the period 1980-89, together with an ongoing case-control study of prospective cases occurring since 1 May 1990.
C
Methods Information on the numbers ofcases of CJD occurring in Scotland and Northern Ireland during the period 1 January 1980 to 31 December 1989 was obtained in the following ways: 1. Death certificates were obtained from the General Register Offices of Scotland and Northern Ireland for all deaths classified under rubrics 046.1 and 331.5 for the period 1 May 1980 to 30 April 1990. 2. Neurologists, neuropathologists and neurophysiologists were circulated asking them to inform us of all cases of Creutzfeldt-Jakob disease known to them during the same period. With the above information it was possible to identify the place of death, or failing this, the centre at which the diagnosis was made, and the medical records department of the hospital concerned was asked to release the case notes. In other cases, general practitioner records were obtained through the local family practitioner committee. Cases were classified as definite, probable, or possible, or not CJD according to the following criteria, based on those of Masters:7 Correspondence and reprint requests to: Dr T.G. Esmonde, Department of Clinical Neurosciences, Western General Hospital, Edinburgh EH4 2XU
Definite: Pathologically proven cases with typical spongiform changes, neuronalloss and astrocytic gliosis. Probable: A history of rapidly progressive dementia, with a typical EEG (generalised repetitive triphasic complexes occurring at I-2Hz), and at least two of the following clinical features: myoclonus, cortical blindness, akinetic mutism, or pyramidal/extra-pyramidal/cerebellar signs. Possible: A history of a rapidly progressive dementia, and at least three of the above clinical features, but without the typical EEG changes. Results Thirty-five cases were identified initially through death certificates. One case diagnosed as suffering from CJD during life, was notified through a neurologist but the cause of death was incorrectly entered on the death certificate. Four clinically undiagnosed cases were discovered at post mortem, but in all of these cases, post mortem was requested because of unusual climical features. Case notes were obtained in all cases except two, and in these some clinical information was found on the autopsy report. Following scrutiny of clinical records, EEG reports, and pathology summaries, the cases were classified into diagnostic categories (Table I). Further analysis of the data was confined to the definite and probable cases. Of these 25 cases, four had origin in Northern Ireland, and 21 in Scotland. Age at onset, and duration of disease are listed in Table II. The yearly incidence of cases is shown in Figure 1, with an annual incidence of 0.37 cases/million. If the cases from the first five years are grouped together and compared with those in the second five year period, there is a significant increase in the Table I Classification of suspected cases of Creutzfeldt-Jakob disease in Scotland and Northern Ireland: 1980-1989 Definite 17 Probable Possible Not em
8 8 7
Total
40
181
Creutzfeldt-Jakob disease
Esmonde and Will
Table II Age and illness duration Age at onset Range Mean SD Definite cases Probable cases
Sex M F
I lIness duration Range Mean SD
64.5
65
12
5
I-22m
6.8
5.5
59-75
66.6
5.4
4
4
I-3m
2.3
0.7
56-77
65.2
6.2
16
9
I-22m
5.3
5.0
56-77
Definite
+ Probable
-"
0036-9330/92/06092/181 $2.00 in USA © 1992 Scottish Medical Journal
CREUTZFELDT-JAKOB DISEASE IN SCOTLAND AND NORTHERN IRELAND 1980.1989
T.G. Esmonde,R.G. Will Department of Clinical Neurosciences, Western General Hospital, Edinburgh Abstract: The epidemiological and clinical features of Creutzfeldt-Jakob disease have never before been studiedin Scotlandand Northern Ireland. Case recordsfor thosedyingwith thisdiagnosis wereobtainedfor theperiod1980-89. Over the tenyearperiod, 25 definite orprobable caseswereidentified, giving an annual incidence of 0.37cases/million. There weremore cases in the second half of the decade, and this was most likelydue to increased ascertainment. One pair of casesoccurredin closeproximity to each other. Sex distribution showedan excessofmales(male female ratio = 1.8 : 1). Mean age at onset was 65.2 years, and meanduration ofdisease was 5.3 months. Thepresenting symptoms and clinicalfeatures weresimilarto thosenotedin previousstudies ofotherpopulations. There was no excessofcases in occupations linkedto food.farming, or medical/paramedical work. Key words: Creutzfeldt-Jakob disease, spongiform encephalopathy, epidemiology, clinical features. Introduction reutzfeldt-JakOb disease (CJD) is a rare, fatal, rapidly progressive dementing illness with distinctive clinical features that was first recognised as a separate entity in 1921.1,2 There is no confirmatory in vivo diagnostic test, and the emergence ofbovine spongiform encephalopathy (BSE) in cattle, with the theoretical risk of transmission to man, has increased the importance of establishing the baseline epidemiological characteristics of CJD. The epidemiology of CJD in England and Wales has been the subject of previous research,3-6but similar studies have not been carried out in Scotland and Northern Ireland. The current paper forms part of a larger nationwide epidemiological survey of Creutzfeldt-Jakob disease comprising analysis of all cases occurring in the period 1980-89, together with an ongoing case-control study of prospective cases occurring since 1 May 1990.
C
Methods Information on the numbers ofcases of CJD occurring in Scotland and Northern Ireland during the period 1 January 1980 to 31 December 1989 was obtained in the following ways: 1. Death certificates were obtained from the General Register Offices of Scotland and Northern Ireland for all deaths classified under rubrics 046.1 and 331.5 for the period 1 May 1980 to 30 April 1990. 2. Neurologists, neuropathologists and neurophysiologists were circulated asking them to inform us of all cases of Creutzfeldt-Jakob disease known to them during the same period. With the above information it was possible to identify the place of death, or failing this, the centre at which the diagnosis was made, and the medical records department of the hospital concerned was asked to release the case notes. In other cases, general practitioner records were obtained through the local family practitioner committee. Cases were classified as definite, probable, or possible, or not CJD according to the following criteria, based on those of Masters:7 Correspondence and reprint requests to: Dr T.G. Esmonde, Department of Clinical Neurosciences, Western General Hospital, Edinburgh EH4 2XU
Definite: Pathologically proven cases with typical spongiform changes, neuronalloss and astrocytic gliosis. Probable: A history of rapidly progressive dementia, with a typical EEG (generalised repetitive triphasic complexes occurring at I-2Hz), and at least two of the following clinical features: myoclonus, cortical blindness, akinetic mutism, or pyramidal/extra-pyramidal/cerebellar signs. Possible: A history of a rapidly progressive dementia, and at least three of the above clinical features, but without the typical EEG changes. Results Thirty-five cases were identified initially through death certificates. One case diagnosed as suffering from CJD during life, was notified through a neurologist but the cause of death was incorrectly entered on the death certificate. Four clinically undiagnosed cases were discovered at post mortem, but in all of these cases, post mortem was requested because of unusual climical features. Case notes were obtained in all cases except two, and in these some clinical information was found on the autopsy report. Following scrutiny of clinical records, EEG reports, and pathology summaries, the cases were classified into diagnostic categories (Table I). Further analysis of the data was confined to the definite and probable cases. Of these 25 cases, four had origin in Northern Ireland, and 21 in Scotland. Age at onset, and duration of disease are listed in Table II. The yearly incidence of cases is shown in Figure 1, with an annual incidence of 0.37 cases/million. If the cases from the first five years are grouped together and compared with those in the second five year period, there is a significant increase in the Table I Classification of suspected cases of Creutzfeldt-Jakob disease in Scotland and Northern Ireland: 1980-1989 Definite 17 Probable Possible Not em
8 8 7
Total
40
181
Creutzfeldt-Jakob disease
Esmonde and Will
Table II Age and illness duration Age at onset Range Mean SD Definite cases Probable cases
Sex M F
I lIness duration Range Mean SD
64.5
65
12
5
I-22m
6.8
5.5
59-75
66.6
5.4
4
4
I-3m
2.3
0.7
56-77
65.2
6.2
16
9
I-22m
5.3
5.0
56-77
Definite
+ Probable
-"
