Somatic symptom overlap in Beck Depression Inventory–II scores following myocardial infarction

Abstract

Depression measures that include somatic symptoms may inflate severity estimates among medically ill patients, including those with cardiovascular disease. To evaluate whether people receiving in-patient treatment following acute myocardial infarction (AMI) had higher somatic symptom scores on the Beck Depression Inventory-II (BDI-II) than a non-medically ill control group matched on cognitive/affective scores. Somatic scores on the BDI-II were compared between 209 patients admitted to hospital following an AMI and 209 psychiatry out-patients matched on gender, age and cognitive/affective scores, and between 366 post-AMI patients and 366 undergraduate students matched on gender and cognitive/affective scores. Somatic symptoms accounted for 44.1% of total BDI-II score for the 209 post-AMI and psychiatry out-patient groups, 52.7% for the 366 post-AMI patients and 46.4% for the students. Post-AMI patients had somatic scores on average 1.1 points higher than the students (P<0.001). Across groups, somatic scores accounted for approximately 70% of low total scores (BDI-II <4) v. approximately 35% in patients with total BDI-II scores of 12 or more. Our findings contradict assertions that self-report depressive symptom measures inflate severity scores in post-AMI patients. However, the preponderance of somatic symptoms at low score levels across groups suggests that BDI-II scores may include a small amount of somatic symptom variance not necessarily related to depression in post-AMI and non-medically ill respondents.