The four-item checklist consists of living alone, alcohol abuse, poor health status as measured by the Kansas City Cardiomyopathy Questionnaire (KCCQ), and the patient's perception that his or her medical care poses a substantial economic burden. A heart failure patient's risk of developing depression within 1 year rises in stepwise fashion as the number of applicable risk factors increases (see box), according to Dr. Havranek of Denver Health Medical Center.
The checklist was developed as part of a multicenter prospective cohort study involving 245 outpatients with heart failure (HF) and a left ventricular ejection fraction less than 40% who were free of depression at baseline. During 1 year of follow-up, 21.5% of patients developed clinically significant symptoms of depression as defined by a score above 0.06 on the widely used Medical Outcomes Study Depression Scale.
Multivariate analysis identified four independent predictors of onset of depression in this HF population. Alcohol abuse was associated with a 3-fold elevated risk, living alone conferred a 2.8-fold risk, and medical care being seen by the patient as a substantial economic burden carried a 2.9-fold increased risk. In addition, the risk of depression rose by 22% for each 10-point decrement on the KCCQ. The study results were published in December (J. Am. Coll. Cardiol. 2004;44:2333-8).
The KCCQ is a self-administered 23-item multiple-choice instrument that inquires about the impact of HF upon a patient's life. For example, the KCCQ asks patients how much swelling in their feet, ankles, or legs has bothered them in the last 2 weeks, how many times during that period they have been forced by shortness of breath to sleep sitting in a chair propped up by at least three pillows, and how much HF has limited their enjoyment of life during the last 2 weeks.
The range of possible scores on the KCCQ is 0-100. Higher scores indicate less disease impact. Study participants with a baseline score greater than 75 had a 13% incidence of depression onset within 1 year. The incidence of depression rose to 20% among those with a baseline score of 51-75, 42% in those who scored 26-50, and 44% with a score of 25 or less.
The impetus for developing the social/health risk factor checklist as a tool for predicting onset of depression stems from prior studies that established depression in patients with HF is quite common and is associated in this population with decline in health status, more frequent hospitalization, and increased mortality.
“Routine screening of high-risk patients with heart failure followed by psychosocial intervention to reduce the incidence of depression is a strategy that deserves study,” Dr. Havranek observed. “This would be consistent with the Institute of Medicine position that one of the changes necessary for American health care is for the system to anticipate patient needs rather than simply to react to events.”