Phenomenology, Etiology, and Severity of Delirium Among Patients Referred to Consultation-liaison Psychiatry Services in a Tertiary Care Hospital: A Cross-sectional Study

Background: Delirium is an acute neuropsychiatric syndrome characterized by disturbances in attention, awareness, and cognition. It is highly prevalent among hospitalized patients but remains under-recognized, particularly in its hypoactive form. Consultation-liaison psychiatry (CLP) services are pivotal for early identification, yet detailed clinical profiles from Indian tertiary-care settings are sparse. Methods: This hospital-based cross-sectional study enrolled 94 adult inpatients referred for acute confusional states between October 2022 and April 2024. We used the Delirium Rating Scale-Revised-98 (DRS-R-98), the Richmond Agitation-Sedation Scale (RASS), and the Delirium Etiology Checklist (DEC). Data were analyzed using descriptive statistics, Chi-square tests, and one-way ANOVA. Statistical significance was set at p < .05. Results: The mean age was 59.29 ± 16.12 years; 81.9% were male. Severe impairment was most frequent in attention (52.1%), short-term memory (50.0%), and orientation (48.9%). Hyperactive delirium was predominant (81.9%). The cohort’s mean total DRS-R-98 score was 21.94 ± 8.12. Increasing age showed a significant association with delirium subtype ( F = 5.68, p = .005), with mixed and hypoactive presentations occurring in older patients. Metabolic/endocrine disturbances (91.5%) and systemic infections (40.4%) were the leading etiological contributors. Conclusions: Delirium in CLP referrals is characterized by marked cognitive impairment, predominance of hyperactive presentation, and multifactorial etiology. The over-representation of hyperactive cases likely reflects referral bias. Structured assessment tools and routine screening are essential for early detection, particularly of hypoactive delirium. Future multicenter prospective studies are warranted.