Correspondence

Childhood Growth and Coronary Events

N Engl J Med 2006; 354:303-304January 19, 2006

Article

To the Editor:

It is likely that the increased insulin resistance observed in patients with rapid childhood growth in the study by Barker et al. (Oct. 27 issue)1 is a function of increased body-mass index (BMI; the weight in kilograms divided by the square of the height in meters) in the subjects as adults. It has been shown that BMI gain in late childhood and adolescence predicts adult adiposity.2 The question is whether the tempo of earlier childhood gain in BMI provides an incremental predictive power with respect to coronary heart disease events beyond the subjects' current BMI and the predictably associated metabolic syndrome. Therefore, the message of this study and its potential pathophysiological implications are unclear without inclusion of the subjects' current BMI in the analysis to allow the cardiovascular effects of acquired obesity in adolescence and adulthood to be differentiated from those that originate in childhood.

Furthermore, coronary heart disease events derived from the national hospital-discharge register in Finland should be interpreted cautiously.3 Smoking status, heredity, and inflammatory markers are all strong predictors of coronary heart disease events. None of these predictors were included in the analysis.

Antonio J. Chamoun, M.D.
Brandywine Valley Cardiovascular Associates, Thorndale, PA 19372
achamoun@comcast.net

Dionne M. Curran-Chamoun, D.O.
940 Horseshoe Pike, Downingtown, PA 19335

3 References

1. 1

   Barker DJ, Osmond C, Forsen TJ, Kajante E, Eriksson JG. Trajectories of growth among children who have coronary events as adults. N Engl J Med 2005;353:1802-1809
   Full Text | Web of Science | Medline

2. 2

   Sachdev HS, Fall CH, Osmond C, et al. Anthropometric indicators of body composition in young adults: relation to size at birth and serial measurements of body mass index in childhood in the New Delhi birth cohort. Am J Clin Nutr 2005;82:456-466
   Web of Science | Medline

3. 3

   Mahonen M, Salomaa V, Brommels M, et al. The validity of hospital discharge register data on coronary heart disease in Finland. Eur J Epidemiol 1997;13:403-415
   CrossRef | Web of Science | Medline

Author/Editor Response

We showed that the path of childhood BMI that led to coronary events began with below-average BMI up to the age of two years. This was followed by rapid increase in z scores (the number of standard deviations above or below the mean value for each measurement among all the children, which is set at zero) for BMI, so that average values were attained around the age of eight years. In the same cohort, the path that led to adult obesity was different. Children who had a BMI above 30 in adult life had above-average and increasing z scores for BMI at all ages from birth.1 A similar effect was present in the New Delhi cohort to which Drs. Chamoun and Curran-Chamoun refer.2 In both cohorts, the development of insulin resistance was associated with thinness in early childhood, with adult BMI taken into account. Our suggestion is that small body size up to the age of two years is associated with persistent reductions in muscle mass and that rapid weight gain thereafter leads to a disproportionately high fat mass in relation to muscle mass.3 Rapid weight gain in children with above-average BMI values since birth may result in a different body composition.

David J.P. Barker, F.R.S.
University of Southampton, Southampton SO16 6YA, United Kingdom
djpb@mrc.soton.ac.uk

Clive Osmond, Ph.D.
MRC Epidemiology Resource Centre, Southampton SO16 6YD, United Kingdom

Johan G. Eriksson, M.D.
National Public Health Institute, 00300 Helsinki, Finland

3 References

1. 1

   Eriksson J, Forsen T, Osmond C, Barker D. Obesity from cradle to grave. Int J Obes Relat Metab Disord 2003;27:722-727
   CrossRef | Web of Science | Medline

2. 2

   Bhargava SK, Sachdev HS, Fall CHD, et al. Relation of serial changes in childhood body-mass index to impaired glucose tolerance in young adulthood. N Engl J Med 2004;350:865-875
   Full Text | Web of Science | Medline

3. 3

   Sayer AA, Syddall HE, Dennison EM, et al. Birth weight, weight at 1 y of age, and body composition in older men: findings from the Hertfordshire Cohort Study. Am J Clin Nutr 2004;80:199-203
   Web of Science | Medline