There is a two-way relationship between depression and cardiovascular disease. Patients with depression are more likely to suffer cardiovascular illness. Likewise patients with cardiovascular disease are more likely to suffer depression. We have shown that patients with depression have markers for vascular abnormalities and that these abnormalities persist even after people have recovered from depression. This suggests that the abnormalities are a persistent characteristic rather than a temporary state. However, it is not known whether the abnormalities occur as a result of depression or are present beforehand. We plan to carry out an analysis of ALSPAC data to examine the hypothesis that those with depression at 18 years will have shown vascular abnormalities at age 10-11 years. If this is the case we will also examine the relationship between vascular abnormalities and depression. This may provide evidence of a causal relationship or shed further light on explanatory factors such as body mass index or exercise levels.