TY - JOUR
T1 - Cost utility and cost-effectiveness of the APPLE-Tree programme: Active Prevention in People at risk of dementia through Lifestyle, bEhaviour change and Technology to build REsiliEnce: economic evaluation embedded within a randomised controlled trial
AU - Demnitz-King, Harriet
AU - Cooper, Claudia
AU - Poppe, Michaela
AU - Budgett, Jessica
AU - Alberts, Sweedal
AU - Duffy, Larisa
AU - Adeleke, Mariam
AU - Barber, Julie
AU - Aguirre, Elisa
AU - Brodaty, Henry
AU - Burton, Alexandra
AU - Higgs, Paul
AU - Huntley, Jonathan
AU - Kales, Helen C
AU - Lang, Iain A
AU - Marchant, Natalie L
AU - Morgan-Trimmer, Sarah
AU - Minihane, Anne Marie
AU - Rapaport, Penny
AU - Rio, Miguel
AU - Ritchie, Karen
AU - Walker, Zuzana
AU - Walters, Kate
AU - Hunter, Rachael M
N1 - Publisher Copyright:
© The Author(s) 2026. Published by Oxford University Press on behalf of the British Geriatrics Society. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.
PY - 2026/6/22
Y1 - 2026/6/22
N2 - Background: Previous studies have modelled long-term cost-effectiveness of dementia prevention but seldom within trials. APPLE-Tree (Active Prevention in People at risk of dementia through Lifestyle, bEhaviour change and Technology to build REsiliEnce) is a personalised, multi-domain, low-intensity dementia prevention intervention for adults experiencing subjective cognitive decline or mild cognitive impairment. Intervention receipt, relative to control, was associated with an adjusted mean difference of 0.06 (95%CI −0.001 to −0.128) in the Neuropsychological Test Battery (NTB). We evaluated cost-effectiveness from health- and social-care perspectives over 2 years. Methods: We recruited 746 older adults from English health and community settings and randomly assigned them (1:1) to APPLE-Tree plus usual care (UC) or UC plus written dementia prevention information. Quality-adjusted life-years (QALYs) were calculated from the EQ-5D-5L. Over 24-months, intention-to-treat analyses compared QALYs (primary) and incremental cost per NTB unit (one z-score) change (secondary). Results: Between October 2020 and December 2022, 374 participants were randomised to intervention and 372 to control. Mean adjusted QALYs were 1.511 (intervention) and 1.520 (control), an adjusted difference of −0.010 (95%CI −0.04 to −0.022). Mean adjusted (SD) costs were £2966 (3629) and £2551 (4439), respectively. Cost per 1-point NTB change z-score was £6809. At a £30 000 threshold, the probability of cost-effective was 12% and 96% based on QALYs and cognition, respectively. Post hoc analyses indicated higher cost-effectiveness for non-White participants (incremental costs: £374; 95%CI −590.751 to −1338.515) and socioeconomically disadvantaged participants (non-homeowners), who had higher QALYs (0.106) and lower costs (−£1830), yielding a 98% probability of cost-effectiveness at a £20 000 threshold. Conclusion: APPLE-Tree has a high probability of being cost-effective for a 1-point NTB gain, a difference previously associated with a three-fold reduction in 5-year dementia risk. QALY-based cost-effectiveness was not observed, but post-hoc analyses suggested it may be more effective in groups with greater needs. Findings highlight the potential of targeted, lower-intensity interventions to reduce dementia risk. Longer-term follow-up is required to determine whether cost-effectiveness is realised over time.
AB - Background: Previous studies have modelled long-term cost-effectiveness of dementia prevention but seldom within trials. APPLE-Tree (Active Prevention in People at risk of dementia through Lifestyle, bEhaviour change and Technology to build REsiliEnce) is a personalised, multi-domain, low-intensity dementia prevention intervention for adults experiencing subjective cognitive decline or mild cognitive impairment. Intervention receipt, relative to control, was associated with an adjusted mean difference of 0.06 (95%CI −0.001 to −0.128) in the Neuropsychological Test Battery (NTB). We evaluated cost-effectiveness from health- and social-care perspectives over 2 years. Methods: We recruited 746 older adults from English health and community settings and randomly assigned them (1:1) to APPLE-Tree plus usual care (UC) or UC plus written dementia prevention information. Quality-adjusted life-years (QALYs) were calculated from the EQ-5D-5L. Over 24-months, intention-to-treat analyses compared QALYs (primary) and incremental cost per NTB unit (one z-score) change (secondary). Results: Between October 2020 and December 2022, 374 participants were randomised to intervention and 372 to control. Mean adjusted QALYs were 1.511 (intervention) and 1.520 (control), an adjusted difference of −0.010 (95%CI −0.04 to −0.022). Mean adjusted (SD) costs were £2966 (3629) and £2551 (4439), respectively. Cost per 1-point NTB change z-score was £6809. At a £30 000 threshold, the probability of cost-effective was 12% and 96% based on QALYs and cognition, respectively. Post hoc analyses indicated higher cost-effectiveness for non-White participants (incremental costs: £374; 95%CI −590.751 to −1338.515) and socioeconomically disadvantaged participants (non-homeowners), who had higher QALYs (0.106) and lower costs (−£1830), yielding a 98% probability of cost-effectiveness at a £20 000 threshold. Conclusion: APPLE-Tree has a high probability of being cost-effective for a 1-point NTB gain, a difference previously associated with a three-fold reduction in 5-year dementia risk. QALY-based cost-effectiveness was not observed, but post-hoc analyses suggested it may be more effective in groups with greater needs. Findings highlight the potential of targeted, lower-intensity interventions to reduce dementia risk. Longer-term follow-up is required to determine whether cost-effectiveness is realised over time.
KW - dementia
KW - health economics
KW - non-pharmacological
KW - older people
KW - prevention
UR - https://www.scopus.com/pages/publications/105042502461
U2 - 10.1093/ageing/afag176
DO - 10.1093/ageing/afag176
M3 - Article
SN - 0002-0729
VL - 55
JO - Age and Ageing
JF - Age and Ageing
IS - 6
M1 - afag176
ER -