Abstract
Background:
The mechanisms underlying the observed association of childhood intelligence with body mass index (BMI) are unclear and few studies of this association have been prospective in design.
Methods:
Prospective study in a birth cohort of 5467 individuals who were born in Aberdeen, Scotland between 1950 and 1956 and who responded to a follow-up survey in 2001. Comparison of associations within sibling pairs of the same family to associations between different families in 643 sibling pairs (1286 individuals) who are participants in the main cohort.
Results:
Childhood intelligence (age 7 years) and educational attainment were both inversely associated with adult BMI (mean age 48 years): the sex- and age-adjusted mean change in adult BMI per s.d. of intelligence was −0.35 kg/m2 (95% CI: −0.49, −0.21 kg/m2) and per unit increase in educational category (seven categories) was −0.28 kg/m2 (95% CI: −0.34, −0.22). On adjustment for education the association between childhood intelligence and adult BMI attenuated to the null (−0.03 kg/m2 (−0.19, 0.13 kg/m2)); other potential confounding or mediating factors had little or only modest effects on this association. The association between education and adult BMI was not affected by adjustment for childhood intelligence or other potential covariates. The within sibling-pair effect of education on adult BMI (−0.06 kg/m2 (95% CI: −0.26, 0.14)) was weaker than the effect between different families (−0.37 kg/m2 (95%CI: −0.58, −0.17)), P-value for difference of within sibling and between family effect=0.03.
Conclusions:
The association of childhood intelligence with adult BMI is attenuated to the null on adjustment for educational attainment, whereas the association of educational attainment with adult BMI appears to be independent of childhood intelligence and other measured covariates. However, our family analyses suggest that fixed family and neighbourhood factors, which are closely matched in siblings of a similar age, explain much of the association between greater educational attainment and lower adult BMI.
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References
Starr JM, Taylor MD, Hart CL, Davey Smith G, Whalley LJ, Hole DJ et al. Childhood mental ability and blood pressure at midlife: linking the Scottish Mental Survey 1932 and the Midspan studies. J Hypertens 2004; 22: 893–897.
Hart CL, Taylor MD, Davey Smith G, Whalley LJ, Starr JM, Hole DJ et al. Childhood IQ, social class, deprivation, and their relationships with mortality and morbidity risk in later life: Prospective observational study linking the Scottish Mental Survey 1932 and the Midspan Studies. Psychosomatic Med 2003; 65: 877–883.
Osler M, Andersen AM, Due P, Lund R, Damsgaard MT, Holstein BE . Socioeconomic position in early life, birth weight, childhood cognitive function, and adult mortality. A longitudinal study of Danish men born in 1953. J Epidemiol Community Health 2003; 57: 681–686.
Kuh D, Richards M, Hardy R, Butterworth S, Wadsworth MEJ . Childhood cognitive ability and deaths up until middle age: a post-war birth cohort study. Int J Epidemiol 2004; 33: 408–413.
Whalley LJ, Deary IJ . Longitudinal cohort study of childhood IQ and survival up to age 76. BMJ 2001; 322: 819.
Sorensen TI, Sonne-Holm S . Intelligence test performance in obesity in relation to educational attainment and parental social class. J Biosoc Sci 1985; 17: 379–387.
Teasdale TW, Sorensen TI, Stunkard AJ . Intelligence and educational level in relation to body mass index of adult males. Hum Biol 1992; 64: 99–106.
Sorensen TI, Sonne-Holm S, Christensen U . Cognitive deficiency in obesity independent of social origin. Lancet 1983; 1: 1105–1106.
Halkjaer J, Holst C, Sorensen TI . Intelligence test score and educational level in relation to BMI changes and obesity. Obes Res 2003; 11: 1238–1245.
Hart CL, Taylor MD, Davey Smith G, Whalley LJ, Starr JM, Hole DJ et al. Childhood IQ and cardiovascular disease in adulthood: prospective observational study linking the Scottish Mental Survey 1932 and the Midspan studies. Soc Sci Med 2004; 59: 2131–2138.
Li X . A study of intelligence and personality in children with simple obesity. Int J Obes Relat Metab Disord 1995; 19: 355–357.
Lissau I, Sorensen TI . School difficulties in childhood and risk of overweight and obesity in young adulthood: a ten year prospective population study. Int J Obes Relat Metab Disord 1993; 17: 169–175.
Datar A, Sturm R, Magnabosco JL . Childhood overweight and academic performance: national study of kindergartners and first-graders. Obes Res 2004; 12: 58–68.
Mo-suwan L, Lebel L, Puetpaiboon A, Junjana C . School performance and weight status of children and young adolescents in a transitional society in Thailand. Int J Obes Relat Metab Disord 1999; 23: 272–277.
Tershakovec AM, Weller SC, Gallagher PR . Obesity, school performance and behaviour of black, urban elementary school children. Int J Obes Relat Metab Disord 1994; 18: 323–327.
Conley D . The Pecking Order: Which Siblings Succeed and Why. Pantheon Books: New York, 2004.
Record RG, McKeown T, Edwards JH . The relation of measured intelligence to birth weight and duration of gestation. Ann Hum Genet 1969; 33: 71–79.
Matte TD, Bresnahan M, Begg MD, Susser E . Influence of variation in birth weight within normal range and within sibships on IQ at age 7 years: cohort study. BMJ 2001; 323: 310–314.
Lawlor DA, Bor W, O’Callaghan MJ, Williams GM, Najman JM . Intrauterine growth and intelligence within sibling pairs: findings from the Mater-University study of pregnancy and its outcomes. J Epidemiol Community Health 2005; 59: 279–282.
Lawlor DA, Clark H, Davey Smith G, Leon DA . Intrauterine growth and intelligence within sibling-pairs: findings from the Aberdeen Children of the 1950s cohort. Pediatrics 2006 (in press).
Leon DA, Koupil I, Mann V, Tuvemo T, Lindmark G, Mohsen R et al. Fetal, developmental and parental influences on childhood systolic blood pressure in 600 sib pairs: The Uppsala Family Study. Circulation 2005; 112: 3478–3485.
Batty GD, Morton SMB, Campbell D, Clark H, Davey Smith G, Hall M et al. The Aberdeen Children of the 1950s cohort study: background, methods, and follow-up information on a new resource for the study of life-course and intergenerational effects on health. Paediatr Perinatal Epidemiol 2004; 18: 221–239.
Nishiwaki Y, Clark H, Morton SM, Leon DA . Early life factors, childhood cognition and postal questionnaire response rate in middle age: the Aberdeen Children of the 1950s study. BMC Med Res Methodol 2005; 5: 16.
Carlin JB, Gurrin LC, Sterne JAC, Morley R, Dwyer T . Regression models for twin studies: a critical review. Int J Epidemiol 2005; 34: 1089–1099.
Power C, Graham H, Due P, Hallqvist J, Joung I, Kuh D et al. The contribution of childhood and adult socioeconomic position to adult obesity and smoking behaviour: an international comparison. Int J Epidemiol 2005; 34: 335–344.
Power C, Elliot J . Cohort profile: 1958 British birh cohort (National Child Development Study). Int J Epidemiol 2005; doi:10.1093/ije/dyil83.
Lawlor DA, Taylor M, Bedford C, Ebrahim S . Agreement between measured and self-reported weight in older women. Results from the British Women's Heart and Health Study. Age Ageing 2001; 31: 169–174.
Hill A, Roberts J . Body mass index: a comparison between self-reported and measured height and weight. J Public Health Med 1998; 20: 206–210.
Acknowledgements
We are very grateful to Raymond Illsley for providing us with the data from the Aberdeen Child Development Survey and for his advice about the study. Graeme Ford played a crucial role in identifying individual cohort members and in helping us initiate the process of revitalisation. Sally Macintyre, Doris Campbell, George Davey Smith, Marion Hall, Bianca De Stavola, Susan Morton, David Batty, David Godden, Diana Kuh, Glyn Lewis and Viveca Östberg collaborated with the authors to revitalise the cohort. Margaret Beveridge assisted Heather Clark in managing the revitalisation. We also thank staff at the ISD (Edinburgh), GRO (Scotland) and NHSCR (Southport) for their substantial contributions and John Lemon who undertook the linkage to the Aberdeen Maternity and Neonatal Databank. Jonathan Sterne (University of Bristol) and John Carlin (University of Melbourne) provided useful statistical advice. Funding: The Aberdeen Children of the 1950s Study was funded as a component project (G0828205) of a Medical Research Council Co-operative Group Life-course and trans-generational influences on disease risk (G9819083). A project on cognition and adult health in the cohort was funded by the Chief Scientists Office, Scottish Executive Health Department. Debbie A Lawlor is funded by a UK Department of Health Career Scientist Award. The views expressed in this paper are those of the authors and not necessarily any funding body. Study ethics: The Scottish multi-centre research ethics committee and local research ethics committees plus the Scottish Privacy Advisory Committee approved the revitalisation of the Children of the 1950s cohort. All record linkage was undertaken by Information and Statistics Division (ISD) of the Scottish Office, who provided us with an anonymised data set for analysis.
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Lawlor, D., Clark, H., Davey Smith, G. et al. Childhood intelligence, educational attainment and adult body mass index: findings from a prospective cohort and within sibling-pairs analysis. Int J Obes 30, 1758–1765 (2006). https://doi.org/10.1038/sj.ijo.0803330
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DOI: https://doi.org/10.1038/sj.ijo.0803330
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