Non-essential symptoms of depression and cognitive impairment no dementia (CIND) in community-dwelling elders without dysphoria or anhedonia

Abstract

Background: Several neuropsychiatric symptoms observed in elders with cognitive impairment no dementia (CIND) can be part of a major depressive episode (MDE) or a "subthreshold" depressive episode. Certain neuropsychiatric symptoms of CIND are essential symptoms of MDE (e.g. dysphoria, anhedonia), while other are non-essential symptoms (NESD; e.g. fatigue, insomnia, cognitive complaint). Contrary to essential symptoms, NESD are not specific to MDE and are present in other disorders. It is unknown whether NESD are linked to CIND in absence of MDE or subthreshold MDE. The present study examined the association between NESD and probable CIND in elders without essential MDE symptoms.

Methods: Participants were 2028 community-dwelling individuals aged 65-96 years who had not experienced dysphoria/anhedonia during the year preceding the interview. Semi-structured in-home interviews evaluated the following NESD: alteration of appetite, sleep disturbance, psychomotor alteration, fatigue/loss of energy, worthlessness/guilt, and cognitive complaints. Probable CIND cases were defined based on the Mini-mental State Examination cut-offs (15th percentile) stratified for age, education and sex.

Results: Symptoms of fatigue/loss of energy (OR: 2.41, 95% CI: 1.42-4.09), sleep disturbance (OR: 3.04 CI: 1.69-5.46) and cognitive complaints (OR: 2.86 CI: 1.71-4.77) were significantly associated with CIND. These associations were not modified after adjustments for potential confounders (age, education level, sex, benzodiazepine use, chronic diseases, and brain disorders).

Conclusion: A psychiatric symptomatology occurs in older adults with CIND in the absence of MDE or subthreshold MDE. NESD encountered in the absence of dysphoria/anhedonia should receive particular attention by clinicians since they can be linked to cognitive difficulties.