Relationship between dementia diagnostic characteristics and severity of depressive symptoms in a cross-sectional...

Depression is a common comorbidity in dementia, with prevalence ranging from 20 to 60% across different countries. This study examined whether depressive symptom severity levels differ by dementia characteristics and country of residence in people living with dementia. This cross-sectional analysis used baseline data from 376 participants in the HOMESIDE trial. Linear regression models examined differences in depressive symptom severity levels by dementia stage, type, severity, and country. In this sample (57% male, mean age 76.6 years), depressive symptom scores were higher for people with severe cognitive impairment than those with mild dementia (MMSE 24-30) (adjusted mean difference: 3.78, 95% CI 1.60-5.96). Mean depressive symptom severity was lower in Norway, Germany, and United Kingdom compared to Australia, with no significant difference for Poland. No apparent differences by dementia type or stage were found. Depressive symptom severity levels differed by cognitive impairment severity and country. Cross-national differences likely reflect a complex interplay of healthcare systems, cultural factors, family support structures, and societal approaches to dementia care. Regular depressive symptom screening is recommended, particularly for severe dementia.Trial registration: ACTRN12618001799246 (Australian New Zealand Clinical Trials Registry) and NCT03907748 (ClinicalTrials.gov).