Amantadine-associated delirium in patients with maintenance dialysis: Insomnia-associated recovery and uneven seasonal distribution

Abstract

Amantadine hydrochloride is a risky drug for triggering delirium in dialysis patients; however, it is often administered casually. Furthermore, little is known regarding the recovery and prognosis of dialysis patients with amantadine-associated delirium. Data of this retrospective cohort study were collected from a local hospital database for hospitalizations between January 2011 and December 2020. Patients were divided into 2 cohorts: early recovery (recovery within 14 days) and delayed recovery (recovery more than 14 days). The cases were analyzed together with the intermonth temperature using descriptive statistics. A Kaplan-Meier survival curve and binary logistic regression were applied for the analyses of prognoses and factors. A total of 57 patients were included in this study. The most common symptoms were hallucinations (45.61%) and muscle tremors (43.86%). Early recovery was observed in 63.16% of the patients. Only 3.51% of the cases occurred in local summer (June, July, and August). Better prognoses for survival (hazard ratio [HR] = 0.066, 95% confidence interval [95% CI] = 0.021-0.212) and hospitalization costs (7968.42 ± 3438.43 CNY vs 12852.38 ± 9361.13 CNY, P = .031) were observed in patients with early recovery than in those with delayed recovery. In the multivariate logistic regression adjusted by 1:1 propensity score matching, delayed recovery was independently caused by insomnia (P = .022, = 10.119, 95% CI = 1.403-72.990) and avoided in patients with urine volume over 300 mL (P = .029, = 0.018, 95% CI = 0.006-0.621). The increment (per 100 mg) of cumulative dose (P = .190, = 1.588, 95% CI = 0.395-3.172) tended to be a risk of delayed recovery. The area under curve of the receiver operating characteristic curve was 0.867, with a sensitivity of 90.5% and a specificity of 82.4% at the cutoff point (cutoff = 0.432). For amantadine-associated delirium in dialysis patients with uneven seasonal distribution, early recovery with better prognosis should be the aim of treatment by giving priority to the remedy of insomnia.