Depression has long been recognised as a risk factor for cardiovascular problems in healthy people and for a worse prognosis in people with existing cardiovascular problems. A study by researchers at the VA Medical Center [sic] in San Francisco followed 1,017 outpatients with stable coronary heart disease for between 4-5 years. It measured their depression symptoms, levels of illness and behaviour over the course of the study. The researchers found that patients with depression had a 10% risk of a subsequent cardiovascular 'event' compared to only a 6.7% risk among those without depression. However, once the researchers adjusted for health behaviours (diet, smoking etc) and physical activity there was no longer a link between depression and subsequent heart problems. The researchers calculated that physical inactivity was associated with a 44% greater rate of cardiovascular 'events.'
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