Living on a farm, contact with farm animals and pets, and childhood acute lymphoblastic leukemia: pooled and meta-analyses from the Childhood Leukemia International Consortium

Laurent Orsi, Corrado Magnani, Eleni T. Petridou, John D. Dockerty, Catherine Metayer, Elizabeth Milne, Helen D. Bailey, Nick Dessypris, Alice Y. Kang, Catharina Wesseling, Claire Infante-Rivard, Victor Wünsch-Filho, Ana M. Mora, Logan G. Spector, Jacqueline Clavel

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The associations between childhood acute lymphoblastic leukemia (ALL) and several factors related to early stimulation of the immune system, that is, farm residence and regular contacts with farm animals (livestock, poultry) or pets in early childhood, were investigated using data from 13 case–control studies participating in the Childhood Leukemia International Consortium. The sample included 7847 ALL cases and 11,667 controls aged 1–14 years. In all studies, the data were obtained from case and control parents using standardized questionnaires. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by unconditional logistic regression adjusted for age, sex, study, maternal education, and maternal age. Contact with livestock in the first year of life was inversely associated with ALL (OR = 0.65, 95% CI: 0.50, 0.85). Inverse associations were also observed for contact with dogs (OR = 0.92, 95% CI: 0.86, 0.99) and cats (OR = 0.87, 95% CI: 0.80, 0.94) in the first year of life. There was no evidence of a significant association with farm residence in the first year of life. The findings of these large pooled and meta-analyses add additional evidence to the hypothesis that regular contact with animals in early childhood is inversely associated with childhood ALL occurrence which is consistent with Greaves’ delayed infection hypothesis.

Original languageEnglish
Pages (from-to)2665-2681
Number of pages17
JournalCancer Medicine
Volume7
Issue number6
DOIs
Publication statusPublished - 1 Jun 2018

Fingerprint

Pets
Domestic Animals
Precursor Cell Lymphoblastic Leukemia-Lymphoma
Meta-Analysis
Leukemia
Odds Ratio
Confidence Intervals
Livestock
Maternal Age
Poultry
Immune System
Cats
Logistic Models
Mothers
Dogs
Education
Farms
Infection

Cite this

Orsi, Laurent ; Magnani, Corrado ; Petridou, Eleni T. ; Dockerty, John D. ; Metayer, Catherine ; Milne, Elizabeth ; Bailey, Helen D. ; Dessypris, Nick ; Kang, Alice Y. ; Wesseling, Catharina ; Infante-Rivard, Claire ; Wünsch-Filho, Victor ; Mora, Ana M. ; Spector, Logan G. ; Clavel, Jacqueline. / Living on a farm, contact with farm animals and pets, and childhood acute lymphoblastic leukemia : pooled and meta-analyses from the Childhood Leukemia International Consortium. In: Cancer Medicine. 2018 ; Vol. 7, No. 6. pp. 2665-2681.
@article{aaf039f777a347b08fae4e713a286d14,
title = "Living on a farm, contact with farm animals and pets, and childhood acute lymphoblastic leukemia: pooled and meta-analyses from the Childhood Leukemia International Consortium",
abstract = "The associations between childhood acute lymphoblastic leukemia (ALL) and several factors related to early stimulation of the immune system, that is, farm residence and regular contacts with farm animals (livestock, poultry) or pets in early childhood, were investigated using data from 13 case–control studies participating in the Childhood Leukemia International Consortium. The sample included 7847 ALL cases and 11,667 controls aged 1–14 years. In all studies, the data were obtained from case and control parents using standardized questionnaires. Pooled odds ratios (ORs) and 95{\%} confidence intervals (CIs) were estimated by unconditional logistic regression adjusted for age, sex, study, maternal education, and maternal age. Contact with livestock in the first year of life was inversely associated with ALL (OR = 0.65, 95{\%} CI: 0.50, 0.85). Inverse associations were also observed for contact with dogs (OR = 0.92, 95{\%} CI: 0.86, 0.99) and cats (OR = 0.87, 95{\%} CI: 0.80, 0.94) in the first year of life. There was no evidence of a significant association with farm residence in the first year of life. The findings of these large pooled and meta-analyses add additional evidence to the hypothesis that regular contact with animals in early childhood is inversely associated with childhood ALL occurrence which is consistent with Greaves’ delayed infection hypothesis.",
keywords = "Animals, childhood leukemia, contact, farm residence",
author = "Laurent Orsi and Corrado Magnani and Petridou, {Eleni T.} and Dockerty, {John D.} and Catherine Metayer and Elizabeth Milne and Bailey, {Helen D.} and Nick Dessypris and Kang, {Alice Y.} and Catharina Wesseling and Claire Infante-Rivard and Victor W{\"u}nsch-Filho and Mora, {Ana M.} and Spector, {Logan G.} and Jacqueline Clavel",
year = "2018",
month = "6",
day = "1",
doi = "10.1002/cam4.1466",
language = "English",
volume = "7",
pages = "2665--2681",
journal = "Cancer Medicine",
issn = "2045-7634",
publisher = "John Wiley & Sons",
number = "6",

}

Orsi, L, Magnani, C, Petridou, ET, Dockerty, JD, Metayer, C, Milne, E, Bailey, HD, Dessypris, N, Kang, AY, Wesseling, C, Infante-Rivard, C, Wünsch-Filho, V, Mora, AM, Spector, LG & Clavel, J 2018, 'Living on a farm, contact with farm animals and pets, and childhood acute lymphoblastic leukemia: pooled and meta-analyses from the Childhood Leukemia International Consortium' Cancer Medicine, vol. 7, no. 6, pp. 2665-2681. https://doi.org/10.1002/cam4.1466

Living on a farm, contact with farm animals and pets, and childhood acute lymphoblastic leukemia : pooled and meta-analyses from the Childhood Leukemia International Consortium. / Orsi, Laurent; Magnani, Corrado; Petridou, Eleni T.; Dockerty, John D.; Metayer, Catherine; Milne, Elizabeth; Bailey, Helen D.; Dessypris, Nick; Kang, Alice Y.; Wesseling, Catharina; Infante-Rivard, Claire; Wünsch-Filho, Victor; Mora, Ana M.; Spector, Logan G.; Clavel, Jacqueline.

In: Cancer Medicine, Vol. 7, No. 6, 01.06.2018, p. 2665-2681.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Living on a farm, contact with farm animals and pets, and childhood acute lymphoblastic leukemia

T2 - pooled and meta-analyses from the Childhood Leukemia International Consortium

AU - Orsi, Laurent

AU - Magnani, Corrado

AU - Petridou, Eleni T.

AU - Dockerty, John D.

AU - Metayer, Catherine

AU - Milne, Elizabeth

AU - Bailey, Helen D.

AU - Dessypris, Nick

AU - Kang, Alice Y.

AU - Wesseling, Catharina

AU - Infante-Rivard, Claire

AU - Wünsch-Filho, Victor

AU - Mora, Ana M.

AU - Spector, Logan G.

AU - Clavel, Jacqueline

PY - 2018/6/1

Y1 - 2018/6/1

N2 - The associations between childhood acute lymphoblastic leukemia (ALL) and several factors related to early stimulation of the immune system, that is, farm residence and regular contacts with farm animals (livestock, poultry) or pets in early childhood, were investigated using data from 13 case–control studies participating in the Childhood Leukemia International Consortium. The sample included 7847 ALL cases and 11,667 controls aged 1–14 years. In all studies, the data were obtained from case and control parents using standardized questionnaires. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by unconditional logistic regression adjusted for age, sex, study, maternal education, and maternal age. Contact with livestock in the first year of life was inversely associated with ALL (OR = 0.65, 95% CI: 0.50, 0.85). Inverse associations were also observed for contact with dogs (OR = 0.92, 95% CI: 0.86, 0.99) and cats (OR = 0.87, 95% CI: 0.80, 0.94) in the first year of life. There was no evidence of a significant association with farm residence in the first year of life. The findings of these large pooled and meta-analyses add additional evidence to the hypothesis that regular contact with animals in early childhood is inversely associated with childhood ALL occurrence which is consistent with Greaves’ delayed infection hypothesis.

AB - The associations between childhood acute lymphoblastic leukemia (ALL) and several factors related to early stimulation of the immune system, that is, farm residence and regular contacts with farm animals (livestock, poultry) or pets in early childhood, were investigated using data from 13 case–control studies participating in the Childhood Leukemia International Consortium. The sample included 7847 ALL cases and 11,667 controls aged 1–14 years. In all studies, the data were obtained from case and control parents using standardized questionnaires. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by unconditional logistic regression adjusted for age, sex, study, maternal education, and maternal age. Contact with livestock in the first year of life was inversely associated with ALL (OR = 0.65, 95% CI: 0.50, 0.85). Inverse associations were also observed for contact with dogs (OR = 0.92, 95% CI: 0.86, 0.99) and cats (OR = 0.87, 95% CI: 0.80, 0.94) in the first year of life. There was no evidence of a significant association with farm residence in the first year of life. The findings of these large pooled and meta-analyses add additional evidence to the hypothesis that regular contact with animals in early childhood is inversely associated with childhood ALL occurrence which is consistent with Greaves’ delayed infection hypothesis.

KW - Animals

KW - childhood leukemia

KW - contact

KW - farm residence

UR - http://www.scopus.com/inward/record.url?scp=85048711635&partnerID=8YFLogxK

U2 - 10.1002/cam4.1466

DO - 10.1002/cam4.1466

M3 - Article

VL - 7

SP - 2665

EP - 2681

JO - Cancer Medicine

JF - Cancer Medicine

SN - 2045-7634

IS - 6

ER -