title: Subsyndromal delirium compared with delirium, dementia, and subjects without delirium or dementia in elderly general hospital admissions and nursing home residents.
abstract: BACKGROUND
  Subsyndromal delirium (SSD) complicates diagnosis of delirium and dementia, although there is little research comparing their symptom profiles.
  
  
  METHODS
  Cross-sectional study of 400 elderly patients' admission to a general hospital or nursing home diagnosed with delirium, SSD, dementia, or no-delirium/no-dementia (NDND). Symptom profiles were assessed using the Delirium Rating Scale-Revised-98 (DRS-R98).
  
  
  RESULTS
  Twenty percent patients had delirium, 19.3% had SSD, 29.8% had dementia-only, and 31% had NDND. Eighty-one percent of subsyndromal and 76% of delirium groups had comorbid dementia. DRS-R98 scores showed ascending severity from NDND < dementia-only < SSD < delirium. DRS-R98 scores for items evaluating the three core symptom domains (cognitive, higher-order thinking, and circadian) distinguished SSD from delirium and both from nondelirium groups. DRS-R98 profiles were essentially the same in delirium and SSD subgroups with or without dementia, although total scale scores were generally higher when in comorbid subgroups.
  
  
  CONCLUSIONS
  SSD shared characteristic core domain symptoms with delirium, which distinguished each from nondelirium groups, although severity was intermediate in the subsyndromal group. Delirium core symptoms overshadowed the dementia phenotype when comorbid. Milder disturbances of delirium core domain symptoms are highly suggestive of SSD.
authors.affiliation: Hospital Psiquiatric Universitari Institut Pere Mata, IISPV, Universitat Rovira i Virgili, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Reus, Tarragona, Spain.
authors.forename: Esteban
authors.initials: E
authors.lastname: Sepulveda
authors.affiliation: University of Limerick Graduate Entry Medical School, Limerick, Ireland; Cognitive Impairment Research Group, Centre for Interventions in Infection, Inflammation and Immunity (4i), Graduate Entry Medical School, University of Limerick, Ireland.
authors.forename: Maeve
authors.initials: M
authors.lastname: Leonard
authors.affiliation: Hospital Psiquiatric Universitari Institut Pere Mata, IISPV, Universitat Rovira i Virgili, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Reus, Tarragona, Spain; Grupo de Investigación en Psiquiatría de Enlace, Escuela de Ciencias de la Salud, Facultad de Medicina, Universidad Pontificia Bolivariana, Medellín, Colombia.
authors.forename: Jose G
authors.initials: JG
authors.lastname: Franco
authors.affiliation: Cognitive Impairment Research Group, Centre for Interventions in Infection, Inflammation and Immunity (4i), Graduate Entry Medical School, University of Limerick, Ireland; Research and Academic Institute of Athens, Athens, Greece; Sligo-Leitrim Mental Health Services, Sligo, Ireland.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Adamis
authors.affiliation: Sligo-Leitrim Mental Health Services, Sligo, Ireland.
authors.forename: Geraldine
authors.initials: G
authors.lastname: McCarthy
authors.affiliation: University of Limerick Graduate Entry Medical School, Limerick, Ireland.
authors.forename: Colum
authors.initials: C
authors.lastname: Dunne
authors.affiliation: Indiana University School of Medicine, Indianapolis, IN, USA; Tufts University School of Medicine, Boston, MA, USA.
authors.forename: Paula T
authors.initials: PT
authors.lastname: Trzepacz
authors.affiliation: Hospital Psiquiatric Universitari Institut Pere Mata, IISPV, Universitat Rovira i Virgili, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Reus, Tarragona, Spain; Universidad de San Buenaventura, Faculty of Psychology, Medellín, Colombia.
authors.forename: Ana M
authors.initials: AM
authors.lastname: Gaviria
authors.affiliation: Hospital Psiquiatric Universitari Institut Pere Mata, IISPV, Universitat Rovira i Virgili, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Reus, Tarragona, Spain.
authors.forename: Joan
authors.initials: J
authors.lastname: de Pablo
authors.affiliation: Hospital Psiquiatric Universitari Institut Pere Mata, IISPV, Universitat Rovira i Virgili, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Reus, Tarragona, Spain.
authors.forename: Elisabet
authors.initials: E
authors.lastname: Vilella
authors.affiliation: University of Limerick Graduate Entry Medical School, Limerick, Ireland; Cognitive Impairment Research Group, Centre for Interventions in Infection, Inflammation and Immunity (4i), Graduate Entry Medical School, University of Limerick, Ireland; Department of Psychiatry, University Hospital Limerick, Limerick, Ireland.
authors.forename: David J
authors.initials: DJ
authors.lastname: Meagher
keywords: Delirium; Dementia; Diagnosis; Elderly; Subsyndromal