Impact of briefly-assessed depression on secondary prevention outcomes after acute coronary syndrome: a one-year longitudinal survey

Patients with acute coronary syndromes (ACS) are at increased risk of further acute cardiac events. Secondary prevention aims to decrease morbidity and mortality post-ACS. Depression is related to increased risk in this population, and to poorer secondary prevention activities. However, lengthy depression assessment techniques preclude depression assessment in routine care. The present study investigated the relationship of briefly-assessed depression with secondary prevention outcomes one year post-ACS.

Following ethics committee approval, hospitals recruited patients for a national survey of ACS. Consenting patients with ACS completed a brief depression scale during hospitalisation. The predictive validity of two brief scales was independently assessed, with groups combined for the overall sample. Participants then completed a one-year longitudinal follow-up postal survey of secondary prevention activities.

The response rate for follow-up was 86% (n = 681). Proportions taking anti-platelet (88% v 87%; p = 0.334) and lipid-lowering (83% v 84%; p = 0.437) therapies remained unchanged. Prevalence of smoking (40% v 22%; p < 0.001), and median number of cigarettes smoked (20 v 10; p < 0.001) were significantly reduced at one year. Fifty-six per cent of patients reported attending cardiac rehabilitation programmes. Of those aged <65 years at baseline, 54% had returned to work at one year. A majority (56%) reported feeling physically better. Prevalence of depression was unchanged in those who completed a depression scale at both time points (15% v 17%; p = 0.434). Baseline depression did not predict taking anti-platelet, blood pressure or cholesterol medications (all p > 0.05), but did predict continuation of smoking (OR = 2.3, 95% CI 1.3–4.0, p = 0.003), a higher (above median) number of general practitioner visits (OR = 2.1, 95% CI 1.3–3.4, p = 0.005), failure to return to work (OR = 0.4, 95% CI 0.2–0.8, p = 0.015), and not feeling better (OR = 0.6, 95% CI 0.3–1.0, p = 0.05) at one year.

Rapid depression assessment can be used to help identify patients with ACS at risk of a range of poorer secondary prevention outcomes. The results provide support for the routine screening of depression in acute settings. Strategies to increase rates of smoking cessation, return to work, general well-being and decrease health service use by depressed patients may need to incorporate some element of treatment for depression.