Similarities in the epidemiology of neural tube defects and coronary heartdisease: is homocysteine the missing link?

It is hypothesised that a single aetiological pathway could explain both th e strong ecological association between the birth prevalence of neural tube defects (NTD) and coronary heart disease (CHD) mortality and the potential efficacy of dietary measures, especially increased folic acid intake, in t heir prevention. The epidemiological similarities between NTD and CHD are s trong and consistent suggesting that the relation is real rather than artef actual. It is suggested that this epidemiological association reflects a sh ared aetiology arising from the role of disturbed homocysteine metabolism i n the pathogenesis of both conditions. Current public health measures desig ned to increase the intake of periconceptional folic acid in women, reinfor ced by a broadening of this policy to target both sexes throughout life, wi ll (if successful) result in a reduction in both the birth prevalence of NT D and the incidence of CHD, although not necessarily contemporaneously. If disordered homocysteine metabolism is the cause of both NTD and CHD, this h as implications for future research and preventive strategies for these ser ious and often lethal diseases.