Disrupted structural covariance network in presbycusis patients: evidence from a large sample mri-based morphometric study.

Cardiac surgery, including coronary artery bypass grafting (CABG) and valve surgery, remains the mainstay of treatment for serious cardiovascular disease (). In high-income countries, annual surgical volumes reach approximately 120–130 per 100,000 population (–). Despite improvements in surgical safety and outcomes, these procedures continue to carry risk of postoperative neuropsychiatric complications, including delirium, cognitive dysfunction, and hallucinations. Hallucinations are sensory perceptions that occur in the absence of external stimuli and may include visual or auditory phenomena. They are increasingly recognized after major cardiac surgery (). In a prospective study, 21.9% of patients developed postoperative hallucinations within the first four days, compared with only 4.1% in a matched cardiology outpatient control group, with visual phenomena being predominant (). Importantly, while many showed concurrent delirium, most hallucinations occurred independently, indicating distinct pathophysiological pathways (, ). Clinically, visual hallucinations (VH) warrant focused attention because they are distressing postoperative perceptual disturbances that may complicate recovery, increase patient and family distress, and contribute to greater postoperative morbidity, prolonged hospitalization, higher healthcare costs, and poorer long-term outcomes (, ). Although VH may occur in the context of delirium, they are not synonymous with delirium and may also occur without the broader disturbances in attention, awareness, and cognition required for delirium diagnosis. Therefore, prediction models developed for postoperative delirium may not fully capture the risk of VH as a distinct clinical outcome. A practical preoperative biomarker-based tool for VH risk stratification may help identify vulnerable patients who could benefit from closer postoperative monitoring and early supportive measures. The C-reactive protein–albumin–lymphocyte (CALLY) index is an emerging biomarker that integrates systemic inflammation, nutritional status, and immune competence, respectively (). Accumulating literature has highlighted the prognostic utility of the CALLY index across diverse clinical contexts, particularly in oncology and critical illness (, ). Consistently, lower CALLY index values have been associated with adverse outcomes, including reduced survival and increased morbidity (–). Its prognostic value may reflect the combined effects of systemic inflammation, malnutrition, and impaired immunity during the postoperative period (). In the setting of cardiac surgery, both inflammation and nutritional decline are common perioperative concerns. Thus, the CALLY index may serve as a promising predictor of postoperative hallucinations and related neuropsychiatric morbidity (). To date, no study has examined the prognostic value of the CALLY index for hallucinations after cardiac surgery. We therefore aimed to evaluate its predictive role and establish an optimal cut-off for this population.