Neuropsychiatric Symptoms in Dementia: Prevalence, Impact, and Implications for Care and Carers - A Systematic Review

BackgroundNeuropsychiatric symptoms (NPS), including agitation, depression, anxiety, psychosis, apathy, and sleep disturbances, are highly prevalent in dementia and significantly contribute to carer burden, accelerated cognitive decline, and increased healthcare utilisation. Despite their clinical relevance, NPS often remain under-recognised and sub-optimally managed. This review synthesises current evidence on the prevalence of NPS in dementia, their functional and psychosocial impacts, and pharmacological and non-pharmacological management approaches.MethodsA systematic search of PubMed, Embase, PsycINFO, and the Cochrane Library (2013-2025) identified observational and interventional studies, which were systematically reviewed and synthesised. Data were independently extracted and quality-assessed.ResultsEighty-two studies (n = 67,945) were included. Neuropsychiatric symptoms were highly prevalent, affecting approximately 78% of individuals with dementia. The most common symptoms were apathy (39%), agitation (35%), and depression (32%), with variation across dementia subtypes. Neuropsychiatric symptoms were associated with functional decline, increased risk of institutionalisation (aHR = 2.15), higher caregiver burden, and increased healthcare costs (approximately 38%). Multicomponent non-pharmacological interventions reduced symptom severity by 18-28%, while pharmacological treatments showed modest efficacy and were associated with increased adverse events. The certainty of evidence ranged from high (prevalence estimates) to moderate (psychosis and hallucinations) and low to moderate (pharmacological interventions).ConclusionNeuropsychiatric symptoms are highly prevalent in dementia and have a substantial impact on patients, carers, and healthcare systems. Individualised non-pharmacological interventions should be first-line, with pharmacological treatments reserved for severe or refractory cases. Early screening and intervention are essential.