A recent systematic review article in the Journal of Dementia and Alzheimer’s Disease exploring the literature base to determine the evidence for benefits and harms for early and/or timely diagnosis in dementia, has called for stronger, more robust evidence of the benefits and potential harms. This review, which updated previous reviews, explored the literature across five large databases. After screening 9316 abstracts, the team identified only four papers that reported the results of quantitative or mixed-methods studies that explored associations between diagnostic timing and outcomes for people with dementia and/or their caregivers. Across these studies, which were published between 2018 and 2021, 37,341 people with dementia were enrolled and 1409 caregivers.
The authors reported that of the studies exploring early versus later diagnosis and cognitive or functional decline (n=1), there was no difference between earlier and later diagnosis and time to cognitive or functional decline. However the original research reported that people with an earlier diagnosis did have relatively better cognition before the cohorts converged. Studies reporting early versus late diagnosis and mortality (n=1) did find that earlier diagnosis was associated with longer survival, however when they adjusted the analysis for confounding factors like baseline cognitive score, they relationship was not observed. Research examining the impact of early versus late diagnosis on emergency services attendance (n=1), indicated that early diagnosis alone was not sufficient to reduce hospitalisations. Lastly, studies examining the impact of early versus late diagnosis on quality of life reported that caregivers who experiences untimely (late) disclosure reported greater sadness and depression and this persisted for linger.
Overall, the authors concluded that there is a significant lack of evidence overall, which is surprising given the volume of guidelines and policy initiatives that recommend early and/or timely diagnosis. Robust quantitative research studies, that employ measures that are important to people with lived experience are urgently needed, for, as the authors suggest, therapeutic nihilism will not be surpassed if there is no proof of the benefits or early or timely diagnosis.
More information on this study is available here: https://www.mdpi.com/3042-4518/3/1/15
