The study examines the behavioural and psychological symptoms (BPSs) associated with dementia and mild cognitive impairment (MCI), highlighting the prevalence and impact of these symptoms on individuals with varying levels of cognitive function, particularly in the context of the increasing incidence of dementia among the ageing population.

To explore the BPSs among out-patients with different cognitive statuses.

This cross-sectional study enrolled out-patients who attended the cognitive assessment out-patient clinic at our hospital between January 2018 and October 2022. The patients’ cognitive status was evaluated using the Neuropsychiatric Inventory (NPI), Activities of Daily Living and the Montreal Cognitive Assessment-Basic scales.

The study enrolled 3273 out-patients, including 688 (21%) with cognitively unimpairment, 1831 (56%) with MCI and 754 (23%) with dementia. The NPI score, the percentage of patients with BPSs and the number of BPSs increased with decreasing cognition level. Unordered logistic regression analysis showed that after adjustment of confounding variables, delusions, depression, euphoria and psychomotor alterations were independently associated with MCI. Delusions, agitation, euphoria, apathy, psychomotor alterations and sleep change were independently associated with dementia.

NPI scores, the percentage of patients with BPSs and the numbers of BPSs increased with declining cognitive function.

Social distancing to limit COVID-19 transmission has led to extensive lifestyle changes, including for people with dementia (PWD). The aim of this study, therefore, was to assess the impact of lockdown on the mental health of PWD and their carers.

Forty-five carers of PWD completed a telephone interview during the baseline assessment of the SOLITUDE study to gather information on life conditions and changes in symptoms of PWD during lockdown. Associations between changes in symptoms of PWD and carers’ concerns and mental health were investigated.

About 44% of carers experienced anxiety and irritability and reported changes in behavioural and cognitive symptoms in PWD. These changes were associated with worse carers’ mental health and concerns about faster disease progression (χ2 = 13.542, p < 0.001).

COVID-19-related social isolation has had a negative impact on patients’ and carers’ mental health. Potential long-term neurocognitive consequences require further investigation.