How do the activities of daily living decline in people living with rarer dementias? A systematic review.

ObjectiveTo study how activities of daily living (ADLs) decline over the progressive course of rarer dementias (prevalence below 10%), in a systematic review of the literature. Methods Relevant studies were identified by searching Medline, Embase, Emcare, PsycINFO and Cinahl. The databases were searched for terms relating to (rarer dementias) AND (activities of daily living) AND (longitudinal OR cross-sectional studies), using a pre-established protocol registered with the international prospective register of systematic reviews (registration: CRD42021283302). ResultsA total of 579 articles were screened for relevant content, of which 20 full-text publications were included in the analysis. Nineteen studies were about rarer dementias on the frontotemporal dementia/primary progressive aphasia spectrum, and one was about posterior cortical atrophy. Long term description of decline was limited to just seven studies following patients for longer than five years. The rate of decline, sequence of symptom onset, and symptom duration were also highlighted. ConclusionDescriptions of ADL progression were inadequately long term, covering an average of 3.5 years from symptom onset, and lacked phenotypic specificity. The literature disproportionately studied dementias on the frontotemporal dementia spectrum. To facilitate better care, more longitudinal data, quantitative analyses, and development of rarer dementia-specific ADL scales is needed. Given the low prevalence of rarer dementias, big data analyses may never be applicable and so personalised medicine approaches should be pursued, including innovative possibilities in digital biomarkers such as from wearable technology.