School of SOCIAL AND COMMUNITY MEDICINE University of BRISTOL ALSPAC AND CROSS-COHORT STUDIES Causal...

School ofSOCIAL AND COMMUNITY

MEDICINE

University ofBRISTOL

ALSPAC AND CROSS-COHORT STUDIES

Causal Effects of Breastfeeding onChild Health Outcomes

Marie-Jo Brion

Sir Henry Wellcome Postdoctoral Fellow

MRC Centre for Causal Analyses in Translational Epidemiology

School of Social and Community Medicine

University of Bristol

MEDICINE

Cause and Effect in Observational Studies:

Getting the Right Answer Examples where observational studies and RCTs fail to arrive at

the same answer

Protective effects on CVD from observational studies : Beta carotene Vitamin E supplements Vitamin C supplements Hormone replacement therapy

Large RCTs showed no protective effect

Likely explanation: confounding in particular, confounding by socioeconomic position

** NEED BETTER CAUSAL APPROACHES **

MEDICINE

What are the causal effects of breastfeeding

on IQ, obesity and blood pressure?

Evidence from comparing high-income

with middle-income cohortsMarie-Jo Brion, Debbie Lawlor, Alicia Matijasevich, Bernardo Horta, Luciana Anselmi,

Ana Maria B Menezes, Cesar Victora, George Davey Smith

Brion et al (2011) IJE 40(3): 670

MEDICINE

Objectives

Explore novel approach for improving causal inference in observational studies

Comparing associations from HIC to LMIC cohorts where associations of confounders with health outcomes are likely to differ between cohorts

Assessing causal effects of breastfeeding on child BP, BMI and IQ

MEDICINE

higher socioeconomic position

healthy diet

physical activity

healthier families

education

Causal effects ??

less smoking

better living conditions

MEDICINE

Methods ALSPAC, UK (N~5000) and Pelotas 1993, Brazil (N~1000)

Meta-analyses of 5 LMIC (COHORTS consortium; N~11,000)Fall et al., IJE 2011

Randomised trial of breastfeeding promotion (PROBIT Belarus trial)Kramer et al., Arch Gen Psychiatry 2008; Kramer et al., AJCN 2007

MEDICINE

Analyses Associations of indicators of SEP with breastfeeding

Maternal education paternal education family income occupational social class

Associations of breastfeeding duration with child outcomes:

MEDICINE

Prevalence (%)

Breastfeeding duration Pelotas ALSPAC

0 to <1 month 15.6% 36.8 %

1 to < 3 months 25.4% 15.6 %

3 to < 6 months 23.6% 13.7 %

6 months or more 35.3% 33.9 %

Ever breastfed 96.8% 84.3%

Exclusive breastfeeding at 2 months 65.7% 38.3%

MEDICINE

Breastfeeding at 3 months according to family income

1 2 3 4 5

Income (Low to High)

Pelotas

ALSPAC

Ever breastfed according to family income

50607080

1 2 3 4 5

Income (Low to High)P

) Pelotas

ALSPAC

MEDICINE

Relative/Slope Index of Inequality

Logistic regression: SEP indicator with binary outcomes Odds of outcome in highest SEP level (1) versus the lowest (0)

Linear regression: SEP indicator with continuous outcomes Difference in outcome between highest SEP level (1) and the lowest (0)

0 .2 .4 .6 .8 1

Cumulative proportion of the population according to income

ALSPAC Pelotas

Breastfeeding by income

MEDICINE

ALSPAC PelotasCohort

ORs for breastfeeding by social class

ORs for breastfeeding by maternal education

ORs for breastfeeding by paternal education

ORs for breastfeeding by income

MEDICINE

ALSPAC Pelotas ALSPAC Pelotas

class income

maternal education paternal education

)Systolic BP

class income

cohort

Diastolic BP-1

class income

maternal education paternal educationdi

MEDICINE

higher socioeconomic position

healthy diet

physical activity

healthier families

education

Causal effects ??

less smoking

better living conditions

Discordant ALSPAC-Pelotas

MEDICINE

Mean difference in outcome by breastfeeding category

OutcomeALSPAC

β (95% CI) P trend

Pelotas

β (95% CI) P trend

SBP, -0.35 (-0.55, -0.14) 0.001 -0.13 (-0.83, 0.57) 0.7(mmHg)

DBP -0.16 (-0.31, -0.01) 0.04 0.05 (-0.50, 0.60) 0.9(mmHg)

BMI -0.16 (-0.22, -0.09) <0.001 0.14 (-0.07, 0.36) 0.2(kg/m2)

IQ 0.97 (0.62, 1.32) <0.001 1.97 (0.88, 3.05) <0.001

Breastfeeding categories: 0 to <1m; 1 to <3m; 3 to <6m; 6m or more

Fully adjusted models

MEDICINE

SBP (mmHg)ALSPACPelotas

p hetero = 0.6

DBP (mmHg)ALSPACPelotas

p hetero = 0.5

BMI (kg/m2)ALSPACPelotas

p hetero = 0.009

IQALSPACPelotas

p hetero = 0.09

CHILD OUTCOME

-0.35 (-0.55, -0.14)-0.13 (-0.83, 0.57)

-0.16 (-0.31, -0.01) 0.05 (-0.50, 0.60)

-0.16 (-0.22, -0.09) 0.14 (-0.07, 0.36)

0.97 (0.62, 1.32)1.97 (0.88, 3.05)

EFFECT SIZE (95% CI)

0-1 -.5 0 .5 1 1.5 2 2.5 3 3.5

ALSPAC-PELOTAS BREASTFEEDING ASSOCIATIONS

MEDICINE

SBP (mmHg)ALSPACPelotas

p hetero = 0.6

DBP (mmHg)ALSPACPelotas

p hetero = 0.5

BMI (kg/m2)ALSPACPelotas

p hetero = 0.009

IQALSPACPelotas

p hetero = 0.09

CHILD OUTCOME

-0.35 (-0.55, -0.14)-0.13 (-0.83, 0.57)

-0.16 (-0.31, -0.01) 0.05 (-0.50, 0.60)

-0.16 (-0.22, -0.09) 0.14 (-0.07, 0.36)

0.97 (0.62, 1.32)1.97 (0.88, 3.05)

0-1 -.5 0 .5 1 1.5 2 2.5 3 3.5

ALSPAC-PELOTAS BREASTFEEDING ASSOCIATIONS

SBP (mmHg)ALSPACCOHORT

p hetero <0.001

DBP (mmHg)ALSPACCOHORT

p hetero = 0.005

BMI (kg/m2)ALSPACCOHORT

p hetero <0.001

CHILD OUTCOME

-0.35 (-0.55, -0.14) 0.12 (-0.01, 0.24)

-0.16 (-0.31, -0.01) 0.10 (-0.01, 0.20)

-0.16 (-0.22, -0.09) 0.04 (0.00, 0.08)

0-1 -.5 0 .5 1 1.5 2 2.5 3 3.5

ALSPAC-LMIC COHORT CONSORTIUM BREASTFEEDING ASSOCIATIONS

MEDICINE

Comparison Method Validation

ALSPAC Strong socioeconomic

patterning in breastfeeding

PelotasWeak socioeconomic patterning

in breastfeeding

BelarusRandomised

Association with any breastfeeding (per category)* Effect of breastfeeding intervention

Outcome β 95% CI P β 95% CI P Difference in outcome

95% CI

SBP, mmHg -0.35 -0.55, -0.14 0.001 -0.13 -0.83, 0.57 0.7 0.2 -2.9, 3.3

DBP, mmHg -0.16 -0.31, -0.01 0.04 0.05 -0.50, 0.60 0.9 0.2 -1.8, 2.2

BMI, kg/m2 -0.16 -0.22, -0.09 <0.001 0.14 -0.07, 0.36 0.2 0.1 -0.2, 0.3

IQ 0.97 0.62, 1.32 <0.001 1.97 0.88, 3.05 <0.001 5.9 -1.0, 12.8

* Adjusted for all indicators of maternal education, paternal education, family income, occupational social class

MEDICINE

Using the totality of the evidence

MEDICINE

Integrating cross-cohorts and additional

causal approachesMaternal prenatal smoking and child aggression:

Exploring intrauterine effects in UK, Australian and

Brazilian cohorts

Marie-Jo Brion, Monique Robinson, Alicia Matijasevich, Colin Steer, Luciana Anselmi, Ana Menezes, Craig Pennell, Lyle Palmer, Cesar Victora, George Davey Smith, Debbie Lawlor

Brion et al. (under review)

MEDICINE

Multi-method approach for assessing intrauterine

mechanisms

MEDICINE

Multivariable Regression

MEDICINE

Cross-cohort confounders

MEDICINE

Maternal-Paternal Comparisons

MEDICINE

Prenatal-Postnatal Comparisons

MEDICINE

Single Method Approach

Conventional multivariable regression independent associations of maternal smoking

and child aggression intrauterine effects as a possible explanation

MEDICINE

Totality of Evidence From Multiple Methods

Total evidence for intrauterine effects is weak Not consistent with SEP being primary / sole determinant Confounding by other familial factors

MEDICINE

ALSPAC and Cross-Cohort Studies

ALSPAC integrated with additional cohorts to explore cross-cohort approach for improving causal inference based on conventional method alone

Value of integrating multiple methods for assessing causal mechanisms to arrive at conclusions based on totality of evidence

Breastfeeding and child BMI, BP and IQ Evidence supporting causal effects breastfeeding duration on greater IQ

Maternal prenatal smoking and child aggression Weak evidence for intrauterine mechanisms Not consistent with SEP being the main explanation for the association Other family-level confounders are likely

MEDICINE

Acknowledgements CAiTE, University of Bristol

Debbie Lawlor George Davey Smith Colin Steer

Federal University of Pelotas Cesar Victora Alicia Matijasevich Bernardo Horta

Other Co-authors: Monique Robinson, Craig Pennell, Lyle Palmer Luciana Anselmi, Ana Menezes

Wellcome Trust UK Henry Wellcome Postdoctoral Fellowship

School of SOCIAL AND COMMUNITY MEDICINE University of BRISTOL ALSPAC AND CROSS-COHORT STUDIES Causal...

Documents

BREASTFEEDING PALN : " Promoting, Protecting and Supporting Breastfeeding "

Breastfeeding promotion interventions and breastfeeding practices… · 2016. 2. 9. · REVIEW Open Access Breastfeeding promotion interventions and breastfeeding practices: a systematic

Breastfeeding Coordinators Breastfeeding Peer Counselor … · Breastfeeding Coordinators Breastfeeding Peer Counselor Supervisors Physical Activity Coordinators Medical Nutrition

static-curis.ku.dk · Larsson et al. HMOs and Weight-Gain During Breastfeeding Conclusion: In a small cohort, we found signiﬁcantly different HMO concentrations in milk to exclusively

Breastfeeding Buddies – Breastfeeding Buddies of Waterloo

Epigenetics and air pollution and ALSPAC

Enough milk? Breastfeeding my baby Breastfeeding in public · Enough milk? Breastfeeding my baby Breastfeeding discomforts Breastfeeding. Enough milk? Suggested Questions: • What

Race, bullying, and psychological well-being at transition to secondary school: The ALSPAC Cohort

BREASTFEEDING ON DEMAND - DiVA portal234135/FULLTEXT01.pdf · Keywords: breastfeeding, breastfeeding on demand, breastfeeding in public, gender equality, individualisation, reflexivity

ALSPAC clinics Larisa Duffy – Clinic Manager l.duffy@bristol.ac.uk

Professional Issues on the Certification Exam discounts ...All children in the cohort benefited from breastfeeding, al‐ though benefits varied depending on their age. Parents did

Effects of Breastfeeding and Breastfeeding in Public

The Hong Kong College of Community Health …...The cohort study revealed that each province of Canada has different trends in breastfeeding. The research “Exclusive breastfeeding

Giving Flight to Imagination - University of North ... · 2010 Cohort 2011 Cohort 2012 Cohort 2013 Cohort 2009 Cohort 2010 Cohort 2011 Cohort 2012 Cohort 2009 Cohort 2010 Cohort 2011

BREASTFEEDING GUIDELINESmoh.gov.bn/Shared Documents/breastfeeding 2020... · Mother can rest while breastfeeding Makes breastfeeding more comfortable and easier following a caesarean

Andrew Smith Dietary patterns in the ALSPAC cohort: Cluster analysis EUCCONET International Workshop 18th October 2011

English Mixing Alcohol and Breastfeeding · Breastfeeding. Resource for mothers and . partners about drinking alcohol while breastfeeding. The Importance of Breastfeeding . Breastmilk

Exclusive Breastfeeding and Breastfeeding in Newspapers

Breastfeeding Friendly Business A Tool Kitdocs.communityconnection.net/Breastfeeding Toolkit.pdf · Breastfeeding Friendly Business: A Tool Kit ... About the Breastfeeding Friendly

ALSPAC Plans and Aspirations On-Line Survey (Clinic1)ALSPAC Plans and Aspirations On-Line Survey (Clinic1) Welcome to the ALSPAC Plans and Aspirations On-Line Survey . This survey