Objectives: Older people reporting subjective memory complaints (SMCs) may have a greater risk of cognitive decline. Multidomain lifestyle interventions are a promising strategy for the prevention of cognitive decline. The aim of this study was to investigate whether the presence of SMCs affects the efficacy of a 2-year multidomain lifestyle intervention on cognition.

Methods: This study is part of the Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER) project. Participants (a subsample of 568 individuals, baseline age 60-77 years) were randomized (1:1) to receive a 2-year multidomain lifestyle intervention group including dietary advice, exercise, cognitive training, and vascular risk management, or regular health advice control group. Cognitive performance was assessed at baseline and at 1- and 2-year visits, using a neuropsychological test battery, including tests assessing memory, executive functions, and processing speed. Participants rated the frequency of SMCs using the Prospective and Retrospective Memory Questionnaire.

Results: Having more retrospective SMCs was linked to a less favorable cognitive trajectory over 2 years. The difference between the intervention and control groups in annual change in tested memory performance was 0.077 (95% CI, 0.008–0.146) among those reporting more retrospective SMCs and −0.011 (−0.074 to 0.053) among those with less SMCs; interaction effect p = .019. No other interactions between SMCs and intervention allocation were observed.

Discussion: A lifestyle intervention may be beneficial for older adults with and without SMCs. Persons having more retrospective SMCs may benefit more from the intervention regarding memory functioning.