Despite this required primary care activity, the published research that suggests the link between CHD and co-morbid depression has been conducted mainly on patients post cardiac event, recruited in secondary care. Patients with CHD have been reported to be at an increased risk of suffering from depression compared to age matched controls. It has also been reported that depression increases all cause mortality in patients with CHD, and that developing depression following an acute myocardial infarction increases cardiac mortality. Pajak explored the prevalence of depression in patients following hospitalisation for coronary heart disease across Europe and found a prevalence of between in men and GNF-1331 in women, depending on country, with a prevalence in the United Kingdom of 19.4% in men and 17.5% in women. While the relationship between CHD and depression may be bidirectional as suggested by these studies, it is not known whether any relationship is maintained as the cardiac event becomes distant in time. Is there a persisting increased risk of depression, for example, in those with a known history of CHD, regardless of current symptoms or disability? Do those with recurrent or persistent depression have more disabling cardiac morbidity or a greater risk of a further cardiac event? If the relationship persists, then an underlying biological mechanism linking them becomes more likely – shared genetic risk and/or SPL-334 enhanced inflammatory response are currently being researched. More could be elucidated with longer-term follow up of less selected populations. Depression, anxiety and coronary heart disease are common amongst consulting patients. The prevalence rate of depression in consecutive attenders across centres participating in the World Health Organisation’s Psychological Problems in General Health Care study. Coronary heart disease is also common in primary care attenders with a prevalence rate of 8% in men and 5% in women over the age of 44 years. The primary care CHD register is an available resource that could be used to explore these questions.