Motoric subtypes of delirium in geriatric patients

Abstract

Aim of the Study: To study the relationship of delirium motor subtypes with cognitive and non-cognitive symptoms of delirium in geriatric patients referred to consultation-liaison psychiatry services. Materials and Methods: Ninety eight (N = 98) consecutive patients (aged ≥60 years) with diagnosis of delirium as per DSM-IV TR were rated on Delirium Rating scale-Revised-98 version (DRS-R-98) and amended Delirium motor symptom scale (DMSS).Results: On amended DMSS, hyperactive subtype (N = 45; 45.9%) was the most common motoric subtype of delirium, followed by hypoactive subtype (N = 23; 23.5%), and mixed subtype (N = 21; 21.4%). On DRS-R-98, all patients fulfilled the criteria of 'acute (temporal) onset of symptoms', 'presence of an underlying physical disorder' and 'difficulty in attention'. In the total sample, >90% of the patients had disturbances in sleep-wake cycle, orientation and fluctuation of symptoms. The least common symptoms were delusions, visuospatial disturbances and motor retardation. When compared to hypoactive group, significantly higher proportion of patients with hyperactive subtype had delusions, perceptual disturbances, and motor agitation. Whereas, compared to hyperactive subtype, significantly higher proportion of patients with hypoactive subtype had thought process abnormality and motor retardation. When the hyperactive and mixed motoric subtype groups were compared, patients with mixed subtype group had significantly higher prevalence of thought process abnormality and motor retardation. Comparison of hypoactive and mixed subtype revealed significant differences in the frequency of perceptual disturbances, delusions and motor agitation and all these symptoms being found more commonly in patients with the mixed subtype. Severity of symptoms were found to be significantly different across the various motoric subtypes for some of the non-cognitive symptoms, but significant differences were not seen for the cognitive symptoms as assessed on DRS-R-98. Conclusion: In elderly patients, motor subtypes of delirium differ from each other on non-cognitive symptom profile in terms of frequency and severity.