Implementation of a best-practice model of care for cognitive impairment and dementia for first nations peoples attending primary care in Australia: a stepped-wedge cluster-randomised trial

Background: Dementia and cognitive impairment not dementia (CIND) are under-detected amongst First Nations peoples attending primary care. This trial implemented a culturally adapted best-practice model of care to increase detection and optimise management of CIND/dementia. Methods: This closed cohort open-label, stepped-wedge, cluster-randomised trial recruited 12 Aboriginal community-controlled primary health care services (ACCHSs) across urban, regional and remote settings in Australia. ACCHSs were eligible to participate if they conducted annual health checks, engaged in continuous quality improvement processes and had ≥55 clients aged ≥50 years. After a baseline control period, four ACCHSs were scheduled to enter the intervention phase every six months. During the intervention phase, ACCHSs were supported to embed best-practice dementia care through staff education and practice change initiatives. Co-primary outcomes were: (i) documented detection of CIND/dementia and, (ii) evidence of uptake of the diagnostic pathway measured as presence of ≥2 of: use of cognitive assessment tools, relevant pathology investigations, neuroimaging, and/or referral of clients with cognitive concerns to specialist services. Data were analysed with mixed effects complementary log–log regression. This study was registered with the Australia and New Zealand Clinical Trials Registry, ACTRN12618001485224. Findings: Between September 2018 and January 2019, 12 ACCHSs were recruited, comprising a sample of 1655 ACCHS clients aged ≥50 years (mean 60.3 ± 8.2 years), of whom 935 (56.5%) were female. One ACCHS withdrew during the study. After adjustment for time, the intervention did not show evidence of an effect for the first co-primary outcome (detection of CIND/dementia): HR = 1.53 (95% CI 0.64, 3.65). However, the intervention improved the second co-primary outcome (uptake of diagnostic pathway): HR = 2.34 (95% CI 1.05, 5.25). Intention-to-treat analyses yielded similar results. Interpretation: The co-developed best-practice model of care for cognitive impairment and dementia for Aboriginal and Torres Strait Islander people attending primary care improved the diagnostic CIND/dementia management process. Funding: National Health and Medical Research Council (Australia) and Dementia Training Australia.