OBJECTIVE: The aim of the study was to assess the relationship between size at birth and obesity as well as truncal fat, and its contribution to cardiovascular risk in a high birth weight population. DESIGN: Cohort-study with retrospectively collected data on size at birth. SETTING: Reykjavik, Iceland. SUBJECTS: A total of 1874 men and 1833 women born in Reykjavik during 1914-1935. MAIN OUTCOME MEASURES: Size at birth. Adult weight, height and skinfold thickness measurements, systolic and diastolic blood pressure, fatal and nonfatal coronary heart disease (CHD). RESULTS: Birth weight was positively related to adult body mass index (BMI) in both genders (B=0.35+/-0.14 kg/m(2), adj. R(2)=0.015, P=0.012 and B=0.34+/-0.17 kg/m(2), adj. R(2)=0.055, P=0.043 in men and women, respectively). However, high birth weight was not a risk factor for adult obesity (BMI>/=30 kg/m(2)). In the highest birth weight quartile, the odds ratio (95% CI) for being above the 90th percentile of truncal fat was 0.7 (0.6-1.0, P=0.021) for men and 0.4 (0.3-0.8, P=0.002) for women, compared with the lowest birth weight quartile. Truncal fat and BMI were positively related to blood pressure in both genders (P<0.05), but not to CHD. The regression coefficient for the inverse association between birth weight and blood pressure hardly changed when adding truncal fat to the model. CONCLUSION: In this high birth weight population, high birth weight was related to higher BMI in adulthood without being a risk factor for adult obesity. The inverse association between birth weight and truncal fat in adulthood suggests a role for foetal development in determining adult fat distribution. The inverse relationship of birth weight to blood pressure seems not to be mediated through the same pathway as to truncal fat.
OBJECTIVE: The aim of the study was to assess the relationship between size at birth and obesity as well as truncal fat, and its contribution to cardiovascular risk in a high birth weight population. DESIGN: Cohort-study with retrospectively collected data on size at birth. SETTING: Reykjavik, Iceland. SUBJECTS: A total of 1874 men and 1833 women born in Reykjavik during 1914-1935. MAIN OUTCOME MEASURES: Size at birth. Adult weight, height and skinfold thickness measurements, systolic and diastolic blood pressure, fatal and nonfatal coronary heart disease (CHD). RESULTS: Birth weight was positively related to adult body mass index (BMI) in both genders (B=0.35+/-0.14 kg/m(2), adj. R(2)=0.015, P=0.012 and B=0.34+/-0.17 kg/m(2), adj. R(2)=0.055, P=0.043 in men and women, respectively). However, high birth weight was not a risk factor for adult obesity (BMI>/=30 kg/m(2)). In the highest birth weight quartile, the odds ratio (95% CI) for being above the 90th percentile of truncal fat was 0.7 (0.6-1.0, P=0.021) for men and 0.4 (0.3-0.8, P=0.002) for women, compared with the lowest birth weight quartile. Truncal fat and BMI were positively related to blood pressure in both genders (P<0.05), but not to CHD. The regression coefficient for the inverse association between birth weight and blood pressure hardly changed when adding truncal fat to the model. CONCLUSION: In this high birth weight population, high birth weight was related to higher BMI in adulthood without being a risk factor for adult obesity. The inverse association between birth weight and truncal fat in adulthood suggests a role for foetal development in determining adult fat distribution. The inverse relationship of birth weight to blood pressure seems not to be mediated through the same pathway as to truncal fat.