Hyperlipidemias: Davey Smith G

Owen CG, Whincup PH, Kaye SJ, Martin RM, Davey Smith G, Cook DG, Bergstrom E, Black S, Wadsworth ME, Fall CH, Freudenheim JL, Nie J, Huxley RR, Kolacek S, Leeson CP, Pearce MS, Raitakari OT, Lisinen I, Viikari JS, Ravelli AC, Rudnicka AR, Strachan DP, Williams SM. · Division of Community Health Sciences, St George's, University of London, London, United Kingdom. · Am J Clin Nutr. · Pubmed #18689365 links to  free full text

Abstract: BACKGROUND: Earlier studies have suggested that infant feeding may program long-term changes in cholesterol metabolism. OBJECTIVE: We aimed to examine whether breastfeeding is associated with lower blood cholesterol concentrations in adulthood. DESIGN: The study consisted of a systematic review of published observational studies relating initial infant feeding status to blood cholesterol concentrations in adulthood (ie, aged >16 y). Data were available from 17 studies (17 498 subjects; 12 890 breastfed, 4608 formula-fed). Mean differences in total cholesterol concentrations (breastfed minus formula-fed) were pooled by using fixed-effect models. Effects of adjustment (for age at outcome, socioeconomic position, body mass index, and smoking status) and exclusion (of nonexclusive breast feeders) were examined. RESULTS: Mean total blood cholesterol was lower (P = 0.037) among those ever breastfed than among those fed formula milk (mean difference: -0.04 mmol/L; 95% CI: -0.08, 0.00 mmol/L). The difference in cholesterol between infant feeding groups was larger (P = 0.005) and more consistent in 7 studies that analyzed "exclusive" feeding patterns (-0.15 mmol/L; -0.23, -0.06 mmol/L) than in 10 studies that analyzed nonexclusive feeding patterns (-0.01 mmol/L; -0.06, 0.03 mmol/L). Adjustment for potential confounders including socioeconomic position, body mass index, and smoking status in adult life had minimal effect on these estimates. CONCLUSIONS: Initial breastfeeding (particularly when exclusive) may be associated with lower blood cholesterol concentrations in later life. Moves to reduce the cholesterol content of formula feeds below those of breast milk should be treated with caution.

Lawlor DA, Davey Smith G, Mitchell R, Ebrahim S. · Department of Social Medicine, University of Bristol, Bristol, UK. · Heart. · Pubmed #15020510 links to  free full text

Abstract: OBJECTIVE: To assess the association of mean outdoor temperature around the time of birth with insulin resistance and coronary heart disease in later life. DESIGN: Cross sectional study. SETTING: 23 British towns. PARTICIPANTS: 4286 women aged 60-79 years. MAIN OUTCOME MEASURES: Coronary heart disease and insulin resistance. RESULTS: Coronary heart disease prevalence was greatest among women born during the coldest months: the age adjusted odds ratio comparing women born in the coldest quarter of monthly outdoor birth temperatures with the remaining three quarters was 1.24 (95% confidence interval (CI) 1.03 to 1.50). Cold outdoor temperature at birth was also associated with increased insulin resistance, increased triglyceride concentrations, and poorer lung function. The link between cold outdoor temperature at birth and coronary heart disease was only partly explained by known coronary disease risk factors: fully adjusted (for all measured potential explanatory and confounding factors) odds ratio 1.19 (95% CI 0.95 to 1.48). The association between cold temperature at birth and coronary heart disease was most pronounced among those whose fathers were either unemployed or in manual social classes when the participants were children, and was non-existent in those from non-manual social classes in childhood. CONCLUSIONS: Cold outdoor temperature at birth is associated with increased coronary heart disease, insulin resistance, dyslipidaemia, and poor lung function. Further research is needed to determine whether this finding reflects events occurring late in the third trimester of intrauterine growth or early in the postnatal period.