Depression Predicts Delirium After Coronary Artery Bypass Graft Surgery Independent of Cognitive Impairment and Cerebrovascular Disease: An Analysis of the Neuropsychiatric Outcomes After Heart Surgery Study

• Published in: The American journal of geriatric psychiatry 2019-05, Vol.27 (5), p.476-486
• Main Authors: Oldham, Mark A., Hawkins, Keith A., Lin, I-Hsin, Deng, Yanhong, Hao, Qing, Scoutt, Leslie M., Yuh, David D., Lee, Hochang B.
• Format: Article
• Language: English
• Subjects: CABG; cerebrovascular disease; Cognitive ability; cognitive impairment; Delirium; depression; Heart surgery; Mental depression
• ISSN: 1064-7481; 1545-7214
• DOI: 10.1016/j.jagp.2018.12.025

•What is the primary question addressed by this study?•Does the risk of delirium after coronary artery bypass graft (CABG) surgery attributable to depression extend beyond that attributable to cognitive impairment and cerebrovascular disease, two conditions commonly comorbid with depression?•What is the main finding of this study?•Preoperative depression (including both major and minor depressive episodes) and mild cognitive impairment are independent risk factors for post-CABG delirium after adjusting for cerebrovascular disease and other relevant covariates (adjusted ORs 9.9 and 5.1, respectively). Interestingly, the severity of right-sided middle cerebral artery stenosis was associated with post-CABG delirium severity, but the severity of left-sided stenosis was not.•What is the meaning of the finding?•Depression and cognitive impairment—including even mild forms of each—deserve recognition for post-CABG delirium risk stratification. Although depression is a known risk factor for delirium after coronary artery bypass graft (CABG) surgery, it is unclear whether this risk is independent of delirium risk attributable to cognitive impairment or cerebrovascular disease. This study examines depression, mild cognitive impairment (MCI), and cerebrovascular disease as post-CABG delirium risk factors. This prospective observational cohort study was performed in a tertiary-care academic hospital. Subjects were without dementia and undergoing CABG surgery. Preoperative cognitive assessment included Clinical Dementia Rating and neuropsychological battery; depression was assessed using Depression Interview and Structured Hamilton. Baseline intracranial stenosis was evaluated by transcranial Doppler of bilateral middle cerebral arteries (MCAs). Study psychiatrists assessed delirium on postoperative days 2–5 using the Confusion Assessment Method. Our analytic sample comprised 131 subjects (average age: 65.8 ± 9.2years, 27% women). MCI prevalence was 24%, preoperative depression 10%, lifetime depression 35%, and MCA stenosis (≥50%) 28%. Sixteen percent developed delirium. Multivariate analysis revealed that age, MCI (odds ratio [OR]: 5.1; 95% confidence interval [CI]: 1.3–20.1), and preoperative depression (OR: 9.9; 95% CI: 1.3–77.9)—but not lifetime depression—predicted delirium. MCA stenosis and severity predicted delirium in univariate but not multivariate analysis. Right MCA stenosis severity predicted delirium severity, but left-sided stenosis severity did not. We