Abstract
Background:
In this preparatory phase of a case–control study, we propose and evaluate a new tool for classifying surgical procedures (SPs) in categories useful for epidemiologic research on surgical transmission of sporadic Creutzfeldt-Jakob disease (sCJD).
Methods:
All SPs reported to the Swedish National Hospital Discharge Registry in the period 1974–2002, and undergone by 212 Swedish patients with registered diagnosis of CJD at death, hospital discharge or notification, in the period 1987–2002, 1060 age-, sex- and residence-matched controls and 1340 randomly chosen population controls, were reclassified into one of six categories of hypothetical transmission risk level. For that purpose the following two attributes were used: non-disposable instruments involved; and highest assigned ad-hoc risk level for four tissues or anatomical structures contacting such instruments.
Results:
A total of 1170 different SP codes were reclassified as follows: 3.1% in the high-risk, 59.1% in the lower-risk, 24.4% in the lowest-risk, and 2.1% in the no-risk groups, with 11.3% procedures negatively defined by rubric as “other than...” being assigned to two spurious diluted-high and diluted-lower risk categories. The high-risk group mainly comprised neurosurgical (53%) and ophthalmic (39%) procedures. Sensitivity of neurosurgery and of ophthalmic surgery excluding neurosurgery, for the high- and diluted-high risk vs. other categories was 46% and 84%, while specificity was 98% and 95%, respectively. Sensitivity analysis based on these indices revealed that non-significant odds ratio effects of 1.4 and 1.3 for neurosurgery and ophthalmic surgery corresponded to statistically significant values of 5.1 after reclassification.
Conclusions:
This classification might contribute to quantify effects masked by use of body-system SP-categories in case–control studies on sCJD transmission by surgery.
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References
Hilton DA, Fathers E, Edwards P, Ironside J, Zajicek J (1998) Prion immunoreactivity in appendix before clinical onset of variant Creutzfeldt-Jakob disease Lancet 352:703–704
Llewelyn CA, Hewitt PE, Knight RWS, et al (2004) Possible transmission of variant Creutzfeldt-Jakob disease by blood transfusion Lancet 363:417–421
Peden AH, Head MW, RitchieDL, Bell JE, Ironside JW (2004) Preclinical vCJD after blood transfusion in a codon 129 heterozygous patient Lancet 364:527–529
Kondo K, Kuroiwa Y (1982) A case–control study of Creutzfeldt-Jakob disease: association with physical injuries Ann Neurol 11:377–381
Davanipour Z, Alter M, Sobel E, Asher DM, Gajdusek DC (1985) Creutzfeldt-Jakob disease: possible medical risk factors Neurology 35:1483–1486
Harries-Jones R, Knight RSG, Will RG, Cousens SN, Smith PG, Matthews WB (1988) Creutzfeldt-Jakob disease in England and Wales, 1980–1984: a case–control study of potential risk factors J Neurol Neurosurg Psychiatry 51:1113–1119
van Duijn CM, Delasnerie-Lauprêtre N, Masullo C, et al (1998) Case–control study of risk factors of Creutzfeldt-Jakob disease in Europe during 1993–95 Lancet 351:1081–1085
Collins S, Law MG, Fletcher A, Boyd A, Kaldor J, Masters CL (1999) Surgical treatment and risk of sporadic Creutzfeldt-Jakob disease: a case–control study Lancet 353:693–697
Zerr I, Brandel JP, Masullo C, et al (2000) European surveillance on Creutzfeldt-Jakob disease: a case–control study for medical factors J Clinical Epidemiol 53:747–754
Ward HJT, Everington D, Croes EA, et al (2002) Sporadic Creutzfeldt-Jakob disease and surgery: a case–control study using community controls Neurology 59:543–548
Wientjens DPWM, Davanipour Z, Hofman A, et al (1996) Risk factors for Creutzfeldt-Jakob disease: a reanalysis of case–control studies Neurology 46:1287–1291
CJD UK Incidents Panel. Management of possible exposure to CJD through medical procedures: a consultation paper. October 2001. pp 11–27 http://www.doh.gov.uk/cjd/consultation
Health Technology and Pharmaceuticals Cluster W. WHO guidelines on Transmissible spongiform encephalopathies in relation to biological and pharmaceutical products. WHO/BCT/QSD/03.01, 1–26. 2003
Rábano A, de Pedro-Cuesta J, Mølbak K, Siden Å, Calero M, Laursen H. Tissue classification for the epidemiologic assessment of surgical transmission of sporadic Creutzfeldt-Jakob disease. A proposal on hypothetical risk levels. BMC Public Health 2005; 5:9
Office of Population, Censuses and Surveys – Classification of Surgical Operations and Procedures – 4th Revision (OPCS-4). http://www.nhsia.nhs.uk/clinicalcoding/pages/opcs_4.asp
Canadian Classification of Diagnostic, Therapeutic, and Surgical Procedures. Ottawa, Ontario: Minister of Industry, Science and Technology; 1993
Klassifikation av operationer, 6:e upplagan. Socialstyrelsen. Norstedts T. Stockholm; 1993
Nordic Medico Statistical Committee N. NOMESCO classification of surgical procedures. Nordic Medico Statistical Committee, NOMESCO; 2003
Greenland S (1998) Basic methods for sensitivity analysis and external adjustment. In: Rothman K, Greenland (Eds), Modern Epidemiology. 2nd Ed. Lippincott & Raven, Philadelphia, PA pp. 347–50
Weissman C, Enari M, Klöhn P-C, Rossi D, Flechsig E (2002) Transmission of prions PNAS 99: 16378–16383
Brown P, Preece M, Brandel J-P, et al (2000) Iatrogenic Creutzfeldt-Jakob disease at the millennium Neurology 55:1075–1081
Frosh A, Joyce R, Johnson A (2001) Iatrogenic vCJD from surgical instruments: the risk is unknown, but improved decontamination will help reduce the risk BMJ 322:1558–1559
Ford MJ, Burton LJ, Morris RJ, Hall SM (2002) Selective expression of prion protein in peripheral tissues of the adult mouse Neuroscience 113:177–192
Glatzel M, et al (2003) Extraneural Pathologic Prion protein in Sporadic Creutzfeldt-Jakob Disease N Eng J Med 349:1812–1820
Norell SE (1995) Obtaining information on exposures. In: Norell SE (ed.), Workbook of Epidemiology. Oxford University Press, Oxford, pp 75–98
Rothman K, Greenland S. Precision and validity in epidemiologic studies. In: Rothman K, Greenland S (eds), Modern Epidemiology. 2nd ed. Lippincott & Raven, Philadelphia, PA, 1998; 11534
Lundberg PO (1998) Creutzfeldt-Jakob Disease in Sweden J Neurol Neurosurg Psychiatry 65:836–41
S-Juan P, Ward HJ, De Silva R, Knight RS, Will RG (2004) Ophthalmic surgery and Creutzfeldt-Jakob disease Br J Ophthalmol. 88:446–449
Acknowledgments
The EUROSURGYCJD group members are grateful to Prof. Maurizio Pocchiari, Italy, for contributing to this proposal with regard to the biological plausibility of surgical transmission of prion disorders, to Margareta Löfdahl (Swedish CJD Surveillance Unit), Curt-Lennar Spetz, Leif Forsberg (Socialstyrelsen) and Lars Caderius (Population Statistics), Sweden, for help with data- collection, and to Margarita Ramírez, Spain, for editorial help. Funding was obtained from The Research Commission EU, Concerted Action QLRG3-CT-2002–81223, and the Spanish RECSP C03–09 and CIEN C03–06 networks. Ethical evaluation was cleared Dnr 452/02 by KI Forskningsetikkommittee Syd on December 2, 2002.
EUROSURGYCJD group members. Spanish team: Javier Almazán, María J. Bleda, Miguel Calero, Ignacio Mahillo, Pablo Martínez-Martín, Jesús de Pedro-Cuesta (coordinator), Alberto Rábano. Danish team: Kåre Mølback, Henning Laursen. Finnish team: Jussi Kovanen. Swedish team: åke Siden, Mabel Cruz.
Consultant experts: Dr.␣Annick Alperovitch, Prof. Paul Brown, Prof. James Ironside, Prof. Maurizio Pocchiari, Prof. Robert G. Will.
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de Pedro-Cuesta, J., Bleda, M.J., Rábano, A. et al. Classification of surgical procedures for epidemiologic assessment of sporadic Creutzfeldt-Jakob Disease transmission by surgery. Eur J Epidemiol 21, 595–604 (2006). https://doi.org/10.1007/s10654-006-9044-7
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DOI: https://doi.org/10.1007/s10654-006-9044-7