Skip to main content
Log in

Association of childhood intelligence with risk of coronary heart disease and stroke: findings from the Aberdeen Children of the 1950s cohort study

European Journal of Epidemiology Aims and scope Submit manuscript

Abstract

Objectives Associations of cognitive function assessed in adulthood with coronary heart disease (CHD) and stroke might reflect a causal effect or could be explained by residual confounding or a common underlying pathology (atherosclerosis) that links both declines in cognitive function and increased risk of cardiovascular disease (i.e. reverse causality). Our objective was to examine the association of childhood intelligence (assessed at an age when generalised atherosclerosis would be extremely unlikely) with risk of CHD and stroke in later life in a cohort of females and males on whom information on a wide range of potential confounding factors is available. Methods Cohort study of 11,125 individuals born in Aberdeen, Scotland, between 1950 and 1956, who had childhood intelligence measured at ages 7, 9, 11 and who have been followed up by linkage to hospital admissions and mortality data. Results The cohort contributed 264,672 person years of follow-up and over this time 93 females experienced CHD and 56 experienced a stroke; 264 males experienced CHD and 67 a stroke. There were inverse associations of childhood intelligence measured at all 3 ages (7, 9, 11 years) with both CHD and stroke, with some evidence that the association with intelligence assessed at age 11 was stronger than at younger ages. The magnitude of associations were similar for CHD and stroke. Adjustment for a range of potential confounding factors did not markedly attenuate the associations and there was evidence that the association was stronger in females than in males. For example, the age adjusted hazard ratio of a combined outcome of CHD and stroke per 1 standard deviation (SD; 1SD = 15 points) difference in intelligence score at age 11 in females was 0.52 (95% CI: 0.42, 0.64) and in males was 0.78 (95% CI: 0.68, 0.90), with adjustment for all potential confounding factors these became 0.60 (95% CI: 0.48, 0.76) and 0.84 (95% CI: 0.72, 0.98) respectively; P-value for interaction with gender in both models =0.002. Adjustment for educational attainment attenuated both associations to the null and removed evidence of a gender difference. Conclusions Our results suggest an association of intelligence in childhood with future CHD and stroke that is unlikely to be explained by reverse causality and was robust to adjustment for a wide range of confounding factors. This association appeared to be mediated by educational attainment. The gender difference seen in our study requires replication in other studies.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. Pavlik VN, de Moraes SA, Szklo M, Knopman DS, Mosley TH Jr, Hyman DJ. Relation between cognitive function and mortality in middle-aged adults: the atherosclerosis risk in communities study. Am J Epidemiol. 2003;157:327–34. doi:10.1093/aje/kwf209.

    Article  PubMed  Google Scholar 

  2. Bassuk SS, Wypij D, Berkman LF. Cognitive impairment and mortality in the community-dwelling elderly. Am J Epidemiol. 2000;151:676–88.

    PubMed  CAS  Google Scholar 

  3. Bruce ML, Hoff RA, Jacobs SC, Leaf PJ. The effects of cognitive impairment on 9-year mortality in a community sample. J Gerontol B Psychol Sci Soc Sci. 1995;50:289–96.

    Google Scholar 

  4. Kelman HR, Thomas C, Kennedy GJ, Cheng J. Cognitive impairment and mortality in older community residents. Am J Public Health. 1994;84:1255–60.

    Article  PubMed  CAS  Google Scholar 

  5. Nguyen HT, Black SA, Ray LA, Espino DV, Markides KS. Cognitive impairment and mortality in older mexican americans. J Am Geriatr Soc. 2003;51:178–83. doi:10.1046/j.1532-5415.2003.51055.x.

    Article  PubMed  Google Scholar 

  6. Fried LP, Kronmal RA, Newman AB, Bild DE, Mittelmark MB, Polak JF, et al. Risk factors for 5-year mortality in older adults: the Cardiovascular Health Study. JAMA. 1998;279:585–92. doi:10.1001/jama.279.8.585.

    Article  PubMed  CAS  Google Scholar 

  7. Gottfredson LS. Intelligence: is it the epidemiologists’ elusive “fundamental cause” of social class inequalities in health? J Pers Soc Psychol. 2004;86:174–99. doi:10.1037/0022-3514.86.1.174.

    Article  PubMed  Google Scholar 

  8. Auperin A, Berr C, Bonithon-Kopp C, Touboul PJ, Ruelland I, Ducimetiere P, et al. Ultrasonographic assessment of carotid wall characteristics and cognitive functions in a community sample of 59- to 71-year-olds. The EVA Study Group. Stroke. 1996;27:1290–5.

    PubMed  CAS  Google Scholar 

  9. Knopman D, Boland LL, Mosley T, Howard G, Liao D, Szklo M, et al. Cardiovascular risk factors and cognitive decline in middle-aged adults. Neurology. 2001;56:42–8.

    PubMed  CAS  Google Scholar 

  10. Manolio TA, Olson J, Longstreth WT. Hypertension and cognitive function: pathophysiologic effects of hypertension on the brain. Curr Hypertens Rep. 2003;5:255–61. doi:10.1007/s11906-003-0029-6.

    Article  PubMed  Google Scholar 

  11. Awad N, Gagnon M, Messier C. The relationship between impaired glucose tolerance, type 2 diabetes, and cognitive function. J Clin Exp Neuropsychol. 2004;26:1044–80. doi:10.1080/13803390490514875.

    Article  PubMed  Google Scholar 

  12. Logroscino G, Kang JH, Grodstein F. Prospective study of type 2 diabetes and cognitive decline in women aged 70–81 years. BMJ. 2004;328:548–51. doi:10.1136/bmj.37977.495729.EE.

    Article  PubMed  Google Scholar 

  13. Batty GD, Deary IJ, Gottfredson LS. Premorbid (early life) IQ and later mortality risk: systematic review. Ann Epidemiol. 2007;17:278–88. doi:10.1016/j.annepidem.2006.07.010.

    Article  PubMed  Google Scholar 

  14. 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;57:681–6. doi:10.1136/jech.57.9.681.

    Article  PubMed  CAS  Google Scholar 

  15. 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. Psychosom Med. 2003;65:877–83. doi:10.1097/01.PSY.0000088584.82822.86.

    Article  PubMed  Google Scholar 

  16. Batty GD, Mortensen EL, Nybo Andersen AM, Osler M. Childhood intelligence in relation to adult coronary heart disease and stroke risk: evidence from a Danish birth cohort study. Paediatr Perinat Epidemiol. 2005;19:452–9. doi:10.1111/j.1365-3016.2005.00671.x.

    Article  PubMed  Google Scholar 

  17. Deary IJ, Whiteman MC, Starr JM, Whalley J, Fox HC. The impact of childhood intelligence on later life: following up the Scottish mental surveys of 1932 and 1947. J Pers Soc Psychol. 2004;86:130–47. doi:10.1037/0022-3514.86.1.130.

    Article  PubMed  Google Scholar 

  18. Hemmingsson T, Melin B, Allebeck P, Lundberg I. The association between cognitive ability measured at ages 18–20 and mortality during 30 years of follow-up—a prospective observational study among Swedish males born 1949–51. Int J Epidemiol. 2006;35:665–70. doi:10.1093/ije/dyi321.

    Article  PubMed  Google Scholar 

  19. Silventoinen K, Modig-Wennerstad K, Tynelius P, Rasmussen F. Association between intelligence and coronary heart disease mortality: a population-based cohort study of 682 361 Swedish men. Eur J Cardiovasc Prev Rehabil. 2007;14:555–60. doi:10.1097/HJR.0b013e328014672e.

    Article  PubMed  Google Scholar 

  20. Hemmingsson T, Essen J, Melin B, Allebeck P, Lundberg I. The association between cognitive ability measured at ages 18–20 and coronary heart disease in middle age among men: a prospective study using the Swedish 1969 conscription cohort. Soc Sci Med. 2007;65:1410–9. doi:10.1016/j.socscimed.2007.05.006.

    Article  PubMed  Google Scholar 

  21. Batty GD, Gale CR, Mortensen LH, Langenberg C, Shipley M, Deary IJ. Pre-morbid IQ, the metabolic syndrome and mortality: the Vietnam Experience Study. Diabetologia. 2008;51:436–43. doi:10.1007/s00125-007-0908-5.

    Article  PubMed  CAS  Google Scholar 

  22. O’Callaghan M, Williams GM, Andersen MJ, Bor W, Najman JM. Social and biological risk factors for mild and borderline impairment of language comprehension in a cohort of five-year-old children. Dev Med Child Neurol. 1995;37:1051–61.

    Article  PubMed  CAS  Google Scholar 

  23. Breslau N, Chilcoat H, DelDotto J, Andreski P, Brown G. Low birth weight and neurocognitive status at six years of age. Biol Psychiatry. 1996;40:389–97. doi:10.1016/0006-3223(95)00399-1.

    Article  PubMed  CAS  Google Scholar 

  24. Lawlor DA, Batty GD, Morton SM, Deary IJ, Macintyre S, Ronalds G, et al. Early life predictors of childhood intelligence: evidence from the Aberdeen children of the 1950s study. J Epidemiol Community Health. 2005;59:656–63. doi:10.1136/jech.2004.030205.

    Article  PubMed  Google Scholar 

  25. Lawlor DA, Najman JM, Batty GD, O’callaghan MJ, Williams GM, Bor W. Early life predictors of childhood intelligence: findings from the Mater-University study of pregnancy and its outcomes. Paediatr Perinat Epidemiol. 2006;20:148–62. doi:10.1111/j.1365-3016.2006.00704.x.

    Article  PubMed  Google Scholar 

  26. Lawlor DA, Sterne JAC, Tynelius P, Davey Smith G, Rasmussen F. The association of childhood socioeconomic position with cause-specific mortality in a prospective record linkage study of 1, 839, 384 individuals. Am J Epidemiol. 2006;164:907–15. doi:10.1093/aje/kwj319.

    Article  PubMed  Google Scholar 

  27. Taittonen L, Nuutinen M, Turtinen J, Uhari M. Prenatal and postnatal factors in predicting later blood pressure among children: cardiovascular risk in young Finns. Pediatr Res. 1996;40:627–32. doi:10.1203/00006450-199610000-00019.

    Article  PubMed  CAS  Google Scholar 

  28. Lawlor DA, Ronalds G, Clark H, Davey Smith G, Leon DA. Birthweight is inversely associated with incident coronary heart disease and stroke among individuals born in the 1950s: findings from the Aberdeen Children of the 1950s prospective cohort study. Circulation. 2005;112:1414–20. doi:10.1161/CIRCULATIONAHA.104.528356.

    Article  PubMed  Google Scholar 

  29. Lawlor DA, Hübinette A, Tynelius P, Leon DA, Davey Smith G, Rasmussen F. The associations of gestational age and intrauterine growth with systolic blood pressure in a family based study of 386,485 men in 331,089 families. Circulation. 2007;115:562–8. doi:10.1161/CIRCULATIONAHA.106.646661.

    Article  PubMed  Google Scholar 

  30. 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;59:2131–8. doi:10.1016/j.socscimed.2004.03.016.

    Article  PubMed  CAS  Google Scholar 

  31. Lawlor DA, Clark H, Davey Smith G, Leon DA. Childhood intelligence, educational attainment and adult body mass index: findings from a prospective cohort and within sibling-pairs analysis. Int J Obes. 2006;30:1758–65. doi:10.1038/sj.ijo.0803330.

    Article  CAS  Google Scholar 

  32. 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 Perinat Epidemiol. 2004;18:221–39. doi:10.1111/j.1365-3016.2004.00552.x.

    Article  PubMed  Google Scholar 

  33. Leon DA, Lawlor DA, Clark H, Macintyre S. Cohort profile: the Aberdeen children of the 1950s study. Int J Epidemiol. 2006;35:549–52. doi:10.1093/ije/dyi319.

    Article  PubMed  Google Scholar 

  34. Illsley R, Wilson F. Longitudinal studies in Aberdeen, Scotland. C. The Aberdeen child development survey. In: Mednick S, Baert A, Bachmann B, editors. Prospective longitudinal research. An empirical basis for the primary prevention of psychosocial disorders. Oxford: Oxford University Press; 1981. p. 66–68.

    Google Scholar 

  35. 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. doi:10.1186/1471-2288-5-16.

    Article  PubMed  Google Scholar 

  36. Royston P. Multiple imputation of missing values. Stata J. 2004;4:227–41.

    Google Scholar 

  37. Kuh D, Richards M, Hardy R, Butterworth S, Wadsworth ME. Childhood cognitive ability and deaths up until middle age: a post-war birth cohort study. Int J Epidemiol. 2004;33:408–13. doi:10.1093/ije/dyh043.

    Article  PubMed  Google Scholar 

  38. Steenland K, Henley J, Thun M. All-cause and cause-specific death rates by educational status for two million peole in two American cancer society cohorts, 1959–1996. Am J Epid. 2002;156:11–21. doi:10.1093/aje/kwf001.

    Article  Google Scholar 

  39. Lawlor DA, Clark H, Leon DA. Associations between childhood intelligence and hospital admissions for unintentional injuries in adulthood: the Aberdeen Children of the 1950s cohort study. Am J Public Health. 2007;97:291–7. doi:10.2105/AJPH.2005.080168.

    Article  PubMed  Google Scholar 

  40. Osler M, Nybo Andersen AM, Laursen B, Lawlor DA. Cognitive function in childhood and early adulthood and injuries later in life: the Metropolit 1953 male birth cohort. Int J Epidemiol. 2007;36:212–9. doi:10.1093/ije/dyl261.

    Article  PubMed  Google Scholar 

Download references

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. Doris Campbell, George Davey Smith, Bianca de Stavola, Marion Hall, David Godden, Diana Kuh, Glyn Lewis, Susan MB Morton and Viveca Östberg collaborated with the authors to revitalise the cohort. Margaret Beveridge assisted Heather Clark in the study management. We would also like to 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. Finally, we thank the study participants.

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). The Scottish Chief Scientist Office provided funds for a study of relationships of childhood intelligence. D. A. Lawlor is funded by a Department of Health (UK) Career Scientist Award and David Batty is a Wellcome Trust Fellow. The UK Medical Research Council (MRC) and the University of Bristol provide core funding for the MRC Centre for Causal Analyses in Translational Epidemiology. The UK MRC and University of Edinburgh provide core funding for the MRC Centre for Cognitive Ageing and Cognitive Epidemiology. The MRC Social and Public Health Sciences Unit receives funding from the UK Medical Research Council and the Chief Scientist Office at the Scottish Government Health Directorates. The views expressed in this paper are those of the authors and not necessarily any funding body. The authors had full access to data and the funding bodies did not influence the data collection, analysis or interpretation of results.

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 ISD, who provided us with an anonymised dataset for analysis.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Debbie A. Lawlor.

Electronic supplementary material

Below is the link to the electronic supplementary material.

(DOCX 22 kb)

Rights and permissions

Reprints and permissions

About this article

Cite this article

Lawlor, D.A., David Batty, G., Clark, H. et al. Association of childhood intelligence with risk of coronary heart disease and stroke: findings from the Aberdeen Children of the 1950s cohort study. Eur J Epidemiol 23, 695–706 (2008). https://doi.org/10.1007/s10654-008-9281-z

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10654-008-9281-z

Keywords

Navigation