title: Infant feeding and school attainment in five cohorts from low- and middle-income countries.
abstract: BACKGROUND
  Performance in intelligence tests tends to be higher among individuals breastfed as infants, but little is known about the association between breastfeeding and achieved schooling. We assessed the association of infant feeding with school achievement in five cohorts from low- and middle-income countries. Unlike high-income country settings where most previous studies come from, breastfeeding is not positively associated with socioeconomic position in our cohorts, thus reducing the likelihood of a spurious positive association.
  
  
  RESULTS
  Participants included 10,082 young adults from five birth cohorts (Brazil, India, Guatemala, the Philippines, and South Africa). The exposures variables were whether the subject was ever breastfed, total duration of breastfeeding, and age at introduction of complementary foods. We adjusted the estimates for age at follow up, sex, maternal age, smoking during pregnancy, birthweight and socioeconomic position at birth. The key outcome was the highest grade achieved at school. In unadjusted analyses, the association between ever breastfeeding and schooling was positive in Brazil, inverse in the Philippines, and null in South Africa; in adjusted analyses, these associations were attenuated. In Brazil, schooling was highest among individuals breastfed for 3-12 months whereas in the Philippines duration of breastfeeding was inversely associated with schooling; and null associations were observed in South Africa and Guatemala. These associations were attenuated in adjusted models. Late introduction of solid foods was associated with lower schooling achievement in Brazil and South Africa.
  
  
  CONCLUSIONS
  Measures of breastfeeding are not consistently related to schooling achievement in contemporary cohorts of young adults in lower and middle-income countries.
authors: Post-Graduate Programme in Epidemiology, Universidade Federal de Pelotas, Pelotas, Brazil.
authors: Bernardo L
authors: BL
authors: Horta
authors: Abet
authors: A
authors: Bas
authors: Santosh K
authors: SK
authors: Bhargava
authors: Caroline H D
authors: CH
authors: Fall
authors: Alan
authors: A
authors: Feranil
authors: Julia
authors: J
authors: de Kadt
authors: Reynaldo
authors: R
authors: Martorell
authors: Linda M
authors: LM
authors: Richter
authors: Aryeh D
authors: AD
authors: Stein
authors: Cesar G
authors: CG
authors: Victora
mesh_terms: D000293:Adolescent; D000328:Adult; D001938:Brazil; D001942:Breast Feeding; D015331:Cohort Studies; D015986:Confounding Factors, Epidemiologic; D003906:Developing Countries / Q000191:economics*; D006166:Guatemala; D006801:Humans; D007182:Income; D007194:India; D007223:Infant; D010679:Philippines; D015995:Prevalence; D012574:Schools; D013019:South Africa; D055815:Young Adult
references: Int J Epidemiol. 2008 Aug;37(4):716-20
references: 18285366
references: J Nutr. 2005 Nov;135(11):2589-95
references: 16251616
references: Int J Epidemiol. 2007 Jun;36(3):504-11
references: 17355979
references: Int J Epidemiol. 2011 Jun;40(3):670-80
references: 21349903
references: J Neurobiol. 2003 Jan;54(1):4-45
references: 12486697
references: Acta Paediatr. 2001 Apr;90(4):460-4
references: 11332943
references: Paediatr Perinat Epidemiol. 2003 Jan;17(1):81-90
references: 12562475
references: Am J Clin Nutr. 1993 May;57(5 Suppl):801S-805S; discussion 805S-806
references: 8475898
references: Ambul Pediatr. 2006 Mar-Apr;6(2):65-71
references: 16530141
references: Am J Hum Biol. 2007 May-Jun;19(3):327-37
references: 17421008
references: J Paediatr Child Health. 2001 Oct;37(5):465-9
references: 11885710
references: Arch Gen Psychiatry. 2008 May;65(5):578-84
references: 18458209
references: Int J Epidemiol. 2011 Feb;40(1):47-62
references: 20852257
references: Soc Sci Med. 1982;16(19):1705-8
references: 7178917
references: Pediatrics. 1998 Jan;101(1):E9
references: 9417173
references: BMJ. 2006 Nov 4;333(7575):945
references: 17020911
references: Am J Clin Nutr. 1999 Oct;70(4):525-35
references: 10500022
references: Soc Sci Med. 1988;26(6):635-9
references: 3363405
references: Pediatrics. 2006 Nov;118(5):e1444-51
references: 17079545
references: JAMA. 2002 May 8;287(18):2365-71
references: 11988057
references: Public Health Nutr. 2002 Oct;5(5):631-5
references: 12372156
references: Am J Hum Biol. 2010 Nov-Dec;22(6):725-30
references: 20721986
references: Lancet. 2007 Jan 13;369(9556):145-57
references: 17223478
references: Soc Sci Med. 2011 May;72(9):1515-21
references: 21474223
references: Acta Paediatr. 2005 Nov;94(11):1656-60
references: 16303706
references: Int J Epidemiol. 2010 Feb;39(1):285-94
references: 19717543
references: Int J Epidemiol. 2012 Jun;41(3):621-6
references: 21224276
references: Soc Sci Med. 2007 Apr;64(7):1407-19
references: 17196724
references: Lancet. 1992 Feb 1;339(8788):261-4
references: 1346280
references: Paediatr Perinat Epidemiol. 2006 Mar;20(2):148-62
references: 16466433
references: N Engl J Med. 2004 Feb 26;350(9):865-75
references: 14985484
references: Arch Dis Child. 2001 Sep;85(3):183-8
references: 11517096
references: Int J Epidemiol. 2006 Apr;35(2):237-42
references: 16373375
references: BMC Med Res Methodol. 2003 Oct 20;3:21
references: 14567763
references: Birth. 2004 Dec;31(4):285-92
references: 15566341