Breast-feeding duration and the risk of malignant diseases in childhood in Sweden

Abstract

Overall, no association between duration of breast-feeding and childhood malignancies was found except for a significantly increased risk for NHL, but this was based on low numbers of cases and needs to be confirmed in other investigations.

Breastfeeding and childhood cancer

“…In conclusion, it is unclear whether the apparent small reduction in the risk of each type of childhood cancer reported here is a nonspecific effect of breastfeeding on childhood cancer or whether it reflects some systematic bias shared by the majority of the casecontrol studies that have investigated aetiological factors in Numbers of cases and controls derived from data presented by the authors c "Never" includes breastfed for < 1 months (Magnani et al 1988, Shu et al 1995, Hardell et al 2001; <2 months (Smulevich et al 1999); ≤ 6 months (Bener et al 2001) Test for heterogeneity ≤ 6 months: χ 3 2 = 1.13; P > 0.1; NS Test for heterogeneity > 6 months: χ 3 2 = 11.64; P < 0.01 Test for heterogeneity between short-term and long-term breastfeeding: Test for heterogeneity ≤ 6 months: χ 3 2 = 1.25; P > 0.1; NS Test for heterogeneity > 6 months: χ 3 2 = 9.30; P < 0.05 Test for heterogeneity between short-term and long-term breastfeeding: …”

“…The results from the UKCCS provide, however, equivocal Test for heterogeneity ≤ 6 months: χ 4 2 = 0.80; P > 0.1; NS Test for heterogeneity > 6 months: χ 4 2 = 17.55; P < 0.01 Test for heterogeneity between short-term and long-term breastfeeding: χ 1 2 = 2.44; P > 0.1; NS a Numbers of cases and controls derived from data presented by the authors b "Never" includes breastfed for < 1 month (Shu et al 1995, Hardell et al 2001; < 2 months (Smulevich et al 1999); ≤6 months ( support for the role of breastfeeding in the aetiology of childhood leukaemia. Although there is weak evidence, of borderline statistical significance, of a small reduction in the odds ratio for leukaemia in children who were breastfed, a reduction in the odds ratio of a similar magnitude was also found for all childhood cancers.…”

“…The results from the UKCCS study with respect to breastfeeding were compared with relevant results from other epidemiological studies of childhood cancer (van Steensel-Moll et al, 1986;McKinney et al, 1987;Davis et al, 1988;Hartley et al, 1988;Magnani et al, 1988;Golding et al, 1990;Shu et al, 1995;Petridou et al, 1997;Grufferman et al, 1998;Dockerty et al, 1999;Schüz et al, 1999;Shu et al, 1999;Smulevich et al, 1999;Infante-Rivard et al, 2000;Rosenbaum et al, 2000;Bener et al, 2001;Hardell and Dreifaldt, 2001). The UKCCS results did not differ significantly from those of previous studies, they have been combined with these and the overall results are shown for leukaemia (Figure 1), Hodgkin's disease (Figure 2), non-Hodgkin's lymphoma (Figure 3), other childhood cancers (Figure 4) and all childhood cancers combined ( Figure 5).…”

“…Several case-control studies of children with leukaemia have reported a significantly reduced risk associated with having been breastfed as infants (Shu et al, 1999;Smulevich et al, 1999;Infante-Rivard et al, 2000;Bener et al, 2001), although not all studies have noted such a relationship (van Steensel-Moll et al, 1986;McKinney et al, 1987;Davis et al, 1988;Magnani et al, 1988;Shu et al, 1995;Petridou et al, 1997;Dockerty et al, 1999;Schüz et al, 1999;Rosenbaum et al, 2000;Hardell and Dreifaldt, 2001). Others have reported a significantly reduced risk of Hodgkin's disease (Grufferman et al, 1998) and non-Hodgkin's lymphoma (Bener et al, 2001) in breastfed children.…”

Breastfeeding patterns and risk of childhood acute lymphoblastic leukaemia

“…To date, 13 case -control studies (Davis et al, 1988;Magnani et al, 1988;van Duijn et al, 1988;Shu et al, 1995;Petridou et al, 1997;Dockerty et al, 1999;McKinney et al, 1999;Schüz et al, 1999;Rosenbaum et al, 2000;Hardell and Dreifaldt, 2001; UK Childhood Cancer Study Investigators, 2001;Lancashire and Sorahan, 2003;Jourdan-Da Silva et al, 2004) have reported no association between breastfeeding and overall childhood leukaemia or ALL risk. Two of these previous studies restricted their analysis to children diagnosed between age 2 and 5 years and found no significant effect of breastfeeding on risk of leukaemia (Shu et al, 1995;UK Childhood Cancer Study Investigators, 2001).…”