Depression and anxiety symptom trajectories in coronary heart disease: Associations with measures of disability and impact on 3-year health care costs

Background: As mortality from coronary heart disease (CHD) falls, years lived with disability increase. Depression and anxiety are known indicators of poor outcomes in CHD, but most research has measured distress symptoms at one time point, often following acute events. Here we consider the long-term trajectories of these symptoms in established CHD, and examine their association to distinct measures of disability and impact on costs. Methods and results: 803 patients with diagnosis of CHD were recruited from primary care, and completed detailed assessments every 6 months for 3 years. Latent class growth analysis (LCGA) was used to identify 5 distinct symptom trajectories based on the Hospital Anxiety and Depression Questionnaire (HADS): 'stable low', 'chronic high', 'improving', 'worsening', and 'fluctuating'. The 'chronic high' group had highest association with reporting of chest pain (RRR 5.8, CI 2.9 to 11.7), smoking (2.9, 1.1 to 6.3), and poorer physical (0.88, 0.83-0.93) and mental (0.78, 0.73-0.84) quality of life. The 'chronic high' and 'worsening' trajectories had significantly higher health-care costs over the 'stable low' trajectory (107.2% and 95.5% increase, respectively). In addition, our trajectories were the only significant variable associated with increased health-care costs across the 3 years. Conclusions: Symptoms of depression and anxiety are highly prevalent in stable CHD patients, and their long-term trajectories are the single biggest driver of health care costs. Managing morbidity in these patients, in which depression and anxiety play a key role in, should become the primary focus of policy makers and future clinical trials.