Aim

The aim of this project is to investigate the associations between diet and blood pressure, measured at 5 years and 7 years in the CIF sample.

Background

Cardiovascular disease is the leading cause of death in industrialised countries, and raised blood pressure is a major risk factor(1). Geographical variations in childhood blood pressure in the UK coincide with geographical variations in adult cardiovascular mortality, and are likely to be related to childhood environment(2). Blood pressure level in childhood has also been shown to track through to adulthood(3). Diet has been shown to relate to blood pressure(4) in childhood and there is evidence that dietary changes in very early life may have persistent effects on blood pressure(5). This suggests that dietary interventions aiming to lower blood pressure in childhood could have an impact on adult cardiovascular mortality. However, data on the associations between diet and blood pressure in childhood are limited. The aim of this study is to investigate the cross-sectional and longitudinal associations between dietary intakes and blood pressure levels measured in the CIF sample at ages 5 and 7 years, taking account of potential confounding variables. Key dietary variables considered will include intakes of sodium, potassium

, magnesium, calcium, fat, protein, wholegrains, fish, fruit and vegetables. These results will be of use in formulating dietary recommendations for children.

References

1. Stamler J, Stamler R, Neaton JD. Blood pressure, systolic and diastolic and cardiovascular risk factors: US population data. Archives of Internal Medicine. 1993;153:598-615.

2. Whincup PH, Cook DG, Adshead F, Taylor S, Papacosta O, Walker M, Wilson V. Cardiovascular risk factors in British children from towns with widely differing adult cardiovascular mortality. BMJ 1996;313:79-84.

3. Kivimaki M et al. Early socioeconomic position and blood pressure in childhood and adulthood: the Cardiovascular Risk in Young Finns Study. Hypertension 2006;47:39-44.

4. Simons-Morton DG et al. Nutrient intake and blood pressure in the Dietary Intervention Study in Children. Hypertension 1997;29:930-936.

5. Geleijnse JM, Hofman A, Witteman JCM et al., Long-term effects of neonatal sodium retention on blood pressure, Hypertension 1996; 29, pp. 913-917.

Data requested

1. Food and nutrient intakes assessed by dietary diary at 5 years and 7 years in the CIF sample

2. Blood pressure measured in the Focus@7 clinic in the CIF sample

3. Blood pressure measured at 5 year clinic in the CIF sample

4. Birthweight, measured or abstracted from medical records

5. Gestational age abstracted from medical records

6. Height and weight and waist circumference at 5 years measured in the CIF clinic

7. Height and weight and waist circumference measured in the Focus@7 clinic in the CIF sample

7. Physical fitness measured at 5 year clinic in the CIF sample

8. Measures of maternal educational level and paternal occupational class by questionnaire

9. Maternal smoking in pregnancy measured by questionnaire

10. Duration of breast-feeding assessed by questionnaire

11. Age of introduction of solids assessed by questionnaire