Cross-sectional analysis of variation in diagnosis of Lewy body dementia in three English regions: data from the DETERMIND programme.

Abstract

We aimed to examine regional differences in the relationship between core clinical features assessed using the Improving the DIAgnosis and Management Of Neurodegenerative Dementias of Lewy body type in the NHS (DIAMOND-Lewy) dementia with Lewy bodies (DLB) Assessment Toolkit and memory service diagnoses of Lewy body dementia (LBD). Secondary analysis of a multicentre observational study. Memory clinics in three sites across England (North East, London and South East) from July 2019 to March 2023. 935 individuals with a new memory service diagnosis of dementia enrolled in the DETERMinants of quality of life, care and costs, and consequences of INequalities in people with Dementia and their carers (DETERMIND) programme. Core clinical features of DLB were assessed using the DLB Assessment Toolkit. The relationship between core clinical features and memory service diagnosis of LBD was examined using Bayesian probit models. There were higher rates of LBD diagnosis from memory services in the cohort in North East England compared with the London and South East centres (11% vs 4%; risk ratio (RR)=1.72 (1.35-2.08)) and evidence of a regional moderating effect on the relationship between clinical features and LBD diagnosis (RR=1.73 (1.26-2.40)).All core clinical features of DLB were associated with LBD diagnosis in North East England, whereas visual hallucinations were the most influential diagnostic feature in London and the South East (RR=3.18 (2.29-4.02)). Regional differences in LBD diagnosis in UK memory services appear to reflect different rates of recognition of specific LBD clinical features. Routinely using a standardised DLB Assessment Toolkit and improving awareness of non-hallucination features in LBD could help to address this disparity.