What is gestational diabetes?

Transcription

1 ESPEN Congress Cannes 2003 Organised by the Israel Society for Clinical Nutrition Education and Clinical Practice Programme Session: Dietitian Symposium: Nutrition throughout the woman life cycle An Update in the Nutritional Management of Gestational Diabetes Doctor Gary Frost And Doctor Anne Dornhorst London, United Kingdom What is gestational diabetes? Find definition WHO This is based on risk if type 2 diabetes Not clear what level of glucose causes problems for the fetus HAPO Study (hyperglycaemic adverse pregnancy outcome study) 25,000 pregnant women with lesser degrees of glucose tolerance will answer this. Detrimental maternal effects Type 2 diabetes CHD ESPEN For personal use only. 1

2 General Dietary Recommendation Poor evidence base Cochrane systematic review 4 studies reached the quality for consideration No relationship between dietary intervention and final birth weight, risk of LGA infant or method of delivery Poorly designed Small underpowered studies Folate Iron General nutrition advice applies Vitamin C Calcium and Vitamin D Alcohol ESPEN For personal use only. 2

3 Hyperglycaemia and the Fetus 1 st trimester congenital malformations 2 nd trimester fetal cell programming 3 rd trimester fetal growth & stillbirth Extra-uterine Sequelle of Intrauterine Hyperglycaemia Neonate transient hypoglycaemia; hypocalcaemia, cardiomyopathy Adolescent obesity, IGT and insulin resistance Adulthood obesity, type 2 DM and?cvd ESPEN For personal use only. 3

4 Fetal Fuels Metabolic changes occur throughout pregnancy to ensure optimal fetal growth. Metabolic changes occur to maximise the maternal-fetal transfer of glucose. Maternal glucose is the primary fetal oxidative substrate and, by late pregnancy, 17-26g glucose are metabolised per day. The maternal respiratory quotient rises during pregnancy as fetal carbohydrate metabolism increases. Barker in reverse: High birth weight and Adult disease Lasting structural and functional adaptation to excess fetal nutrient supply Fetal insulin a key fetal growth factor, determines fat and muscle mass at birth Fuel-mediated teratogenesis that effects the adipoinsular axis, leading to insulin resistance, childhood obesity and future diabetes There is a U shape relationship between birth weight and future type 2 diabetes ESPEN For personal use only. 4

5 Diagnosed Type 2 Diabetes USA Prevalence Data 8 8,000,000 Persons With Diagnosed Diabetes (millions) X increase Year Diabetes Overview. October 1995 (updated 1996). NIDDK publication NIH Kenny SJ et al. In: Diabetes in America. 2nd ed. 1995: Obesity Past and Future ESPEN For personal use only. 5

6 Disease Risk and Body Mass Increasing US Prevalence of Type 2 Diabetes in Diagnosed type 2 Diabetes È 4.9% - 6.5% yr. È 40% yr. È 70% Type 2 diabetes is increasing USA teenagers Mokdad et al, Diabetes trends in the U.S.: Diabetes Care, : p ESPEN For personal use only. 6

7 Pima Indian in Arizona Maintained traditional lifestyle up until 1900 when water supply was diverted by white farmers and they become dependent on U.S. government supply of food - lard, sugar,white flour Pima Indian Woman 1902 Pima Indians environment verses genes The Pima Indians from Arizona have changed from a subsistence existence to Western lifestyle Pima Indian ancestors live in a mountainous remote undeveloped area of NW-Mexico Ravussin et al Diabetes Care : ESPEN For personal use only. 7

8 Increasing Prevalence of Type 2 DM in Pima Indian Girls 5-9yrs 10-14yrs 15-19yrs 6 Pravelence % children examined over 30 years. The prevalence has increased 2-3 fold over this time Dabelea et al. J Matern-Fetal Med 2000;9:83-88 Prevalence of Type 2 DM According to Maternal Diabetic Status Dabelea et al. J Matern-Fetal Med 2000;9:83-88 Non-DM Pre-DM DM Pravelence % years ESPEN For personal use only. 8

9 The Lasting Legacy of Maternal Hyperglycaemia Maternal hyperglycaemia accounts for 40% of Type 2 DM in the Pima children <19-yrs. There is an increased risk of Type 2 DM in children of Type 1 mothers, and the risk appears dependent on glycaemic control in pregnancy. Likely to explain the higher maternal than paternal family history of DM. Obesity management Population based: Obesity is a major public health problem To prevent GDM need to prevent obesity ESPEN For personal use only. 9

10 Mean Weight Change Weight Change (kg) Years from Randomization Placebo Metformin Lifestyle The DPP Research Group, NEJM 346: , 2002 Cumulative incidence (%) Incidence of Diabetes Incidence Percent developing of diabetes Diabetes Placebo (n=1082) All participants Metformin (n=1073, p<0.001 vs. Placebo) Lifestyle (n=1079, p<0.001 vs. Met, p<0.001 vs. Plac ) Lifestyle Metformin (n=1079, (n=1073, p<0.001 vs. vs. Plac) Metformin, Placebo (n=1082) p<0.001 vs. Placebo) Risk reduction 31% by metformin 58% by lifestyle Years from randomization The DPP Research Group, NEJM 346: , 2002 ESPEN For personal use only. 10

11 In pregnancy Obesity management Dutch famine (800kcal/day) thin babies, more diabetes Maternal ketosis effects fetal neuro-physiological and cognative development Moderate energy restriction 25kcal/kg/day from 24 th week, limits weight gain, LGA reduced. Women only gained half weight of controls (Dornhorst 1991, Knopp 1991) Long chain polyunsaturates Hammersmith Hospitals NHS Trust ESPEN For personal use only. 11

12 Long chain polyunsaturates (LCPs) Man cannot insert double bonds at the n3 and n6 positions in fatty acids therefore. Hammersmith Hospitals NHS Trust Long chain polyunsaturates (LCPs) Linoleic acid (double bonds at the n6 position) and Alpha linolenic acid (double bonds at the n3 position) are ESSETIAL FATTY ACIDS and are the precursors of LCPs Hammersmith Hospitals NHS Trust ESPEN For personal use only. 12

13 Long chain polyunsaturates (LCPs) Arachidonic acid (n6) : Docosahexaenoic acid (n3) Ratio in brain 2:1 Hammersmith Hospitals NHS Trust Development of the cortex 24 weeks to term Hammersmith Hospitals NHS Trust ESPEN For personal use only. 13

14 Fish oils and gestational diabetes Insulin resistance & altered maternal metabolism in gestational diabetes impairs arachidonic acid and DHA. Low levels in cord blood Impairment of accretion may effect fetal accretion of DHA and AA Maternal supplements effect IQ Low consumption in many countries is a problem Fish consumption Recent evidence suggested an increase spontaneous abortion rate in low fish consuming countries Is this due to DHA? Does a maternal background of abnormal glucose tolerance decrease levels further? Role in hypertensive crisis? Small study evidence. ESPEN For personal use only. 14

15 What is Glycaemic Index Incremental area under the blood glucose response curve for food Corresponding area after equicarbohydrate portion of glucose X 100 Glycaemic response of carbohydrates White Bread Wholemeal Bead White pasta Kidney beans 12 Delta change in glucose (mmol/l) Time (minutes) ESPEN For personal use only. 15

16 Glycaemic index FOOD White bread Wholemeal bred Brown rice White rice Boiled potato Pasta Yam Green banana Sucrose Baked beans Chickpeas GI Glycaemic index Potential of decreasing risk of developing type 2 diabetes Potential of decreasing risk of CHD Potential effect of decreasing body weight Mechanism Improving insulin sensitivity Adipose tissue Summerbell and Frost. Systematic Review of glyceamic index, Cochrane Reviews 2003 ESPEN For personal use only. 16

17 Feto-placental growth regulation Rate of substrate delivery to the placental site Release of placental growth or suppressive peptides into the umbilical circulation Production of IGF and IGFBP by the liver and other tissues Rate of feto-placental growth Clapp etal 1991 Glycaemic index in GDM Low GI meal causes a lower post-prandial insulin and glucose response Low GI diet blunt the mid and late pregancy insulin resistance High GI larger infants Low GI limited energy intake, and weight gain in the mother Clapp Proc Nutr Soc 2003 ESPEN For personal use only. 17

18 Glycaemic index in GDM Low blood glucose measurement Reduction in hypos Improved fasting blood glucose Gestational Diabetes: Potential Relevance of Diet A important factor fuelling the current rise in adolescent obesity & type 2 DM We need evidence of effective interventions Potential areas of interest are: Fish oils Carbohydates ESPEN For personal use only. 18

19 The End ESPEN For personal use only. 19