Spatial temporal patterns in childhood leukaemia: further evidence for an infectious origin. EUROCLUS project.
The EUROCLUS project included information on residence at diagnosis for 13351 cases of childhood leukaemia diagnosed in the period 1980-89 in defined geographical regions in 17 countries. A formal algorithm permits identification of small census areas as containing case excesses. The present analysis examines spatial-temporal patterns of the cases (n = 970) within these clustered areas. The objectives were, first, to compare these results with those from an analysis conducted for UK data for the period 1966-83, and, second, to extend them to consider infant leukaemias. A modification of the Knox test investigates, within the small areas, temporal overlap between cases in a subgroup of interest at a putative critical time and all other cases at any time between birth and diagnosis. Critical times were specified in advance as follows: for cases of acute lymphoblastic leukaemia aged 2-4 years, the 18-month period preceding diagnosis; for cases of total leukaemia aged 5-14 years, 1 year before to 1 year after birth; and for infant cases (diagnosed < 1 year), 1 year before to 6 months after birth. Each of the analyses found evidence of excess space-time overlap compared with that expected; these were 10% (P = 0.005), 15% (P= 0.0002) and 26% (P= 0.03) respectively. The results are interpreted in terms of an infectious origin of childhood leukaemia.
Alexander
F E
FE
Department of Public Health Sciences, The University of Edinburgh, Medical School, UK.
Boyle
P
P
Carli
P M
PM
Coebergh
J W
JW
Draper
G J
GJ
Ekbom
A
A
Levi
F
F
McKinney
P A
PA
McWhirter
W
W
Magnani
C
C
Michaelis
J
J
Olsen
J H
JH
Peris-Bonet
R
R
Petridou
E
E
Pukkala
E
E
Vatten
L
L
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D016000:Cluster Analysis; D005060:Europe / Q000453:epidemiology; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D007239:Infections / Q000150:complications*; D007938:Leukemia / Q000453:epidemiology; D008228:Lymphoma, Non-Hodgkin / Q000453:epidemiology; D008297:Male; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000453:epidemiology* / Q000209:etiology*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious; D011297:Prenatal Exposure Delayed Effects; D012306:Risk; D013997:Time Factors