ISCHEMIC-HEART-DISEASE AND LOW-BIRTH-WEIGHT - A TEST OF THE FETAL-ORIGINS HYPOTHESIS FROM THE SWEDISH-TWIN-REGISTRY

Twins constitute a population with lower than average birth weight for reasons that are not a consequence of social disadvantage. The hypoth esis that ischaemic heart disease (IHD) is linked to low birth weight was tested by analysing whether or not 8174 female and 6612 male Swedi sh twins had a higher mortality compared to the general Swedish popula tion. The association between adult body height and IHD mortality was also analysed in a nested case-control study among monozygotic and diz ygotic twins. Ischaemic heart disease mortality was not higher among t wins (women: relative risk [RR] 0.99; 95% confidence limits [CL] 0.89- 1.10; men: RR 0.85; CL 0.79-0.92). However, the shorter twin in a twin pair was more likely to die of heart disease than the taller (odds ra tio [OR] 1.15, CL 1.03-1.25). We suggest that postnatal influences may well be as important as prenatal influences in producing any effect o n ischaemic heart disease mortality and that the type of growth retard ation in utero experienced by twins may not constitute a risk for isch aemic heart disease in adulthood.