The effect of a mindfulness‐based versus health self‐management intervention on cognitive performance in older adults with subjective cognitive decline (SCD): The SCD‐Well randomized controlled trial

Abstract

AbstractBackgroundSubjective cognitive decline (SCD) denotes self‐reported cognitive concerns in the absence of objective cognitive impairment. Individuals with SCD convert to dementia at twice the annual rate of healthy controls, with relatively poorer cognition in SCD conferring additional risk. Non‐pharmacological interventions are currently undergoing intensive evaluation for promoting cognitive function in SCD.MethodThis study utilized data from the SCD‐Well randomized controlled trial. One hundred forty‐seven older adults with SCD, recruited from clinics in four European countries, were randomized to one of two 8‐week non‐pharmacological interventions: the Caring Mindfulness‐Based Approach for Seniors (CMBAS), or a Health Self‐Management Program (HSMP). Participants’ objective cognitive performance was assessed at baseline, post‐intervention, and 24‐weeks follow‐up using a battery of tests. Four of these (RAVLT, WAIS‐IV Coding, Mattis DRS‐2 and Category Fluency) were combined to yield an abridged version of the Preclinical Alzheimer’s Cognitive Composite 5 (PACC5Abridged). Linear mixed models estimated the change in outcome measures (the PACC5Abridged and its constituents) within and between arms. All models were adjusted for country and participant demographics (sex, age, and education), as well as the time‐varying effect of participants’ repeated practice with the outcome measures.ResultThere was a statistically significant improvement in the PACC5Abridged in both arms of the trial (p<.001), which did not differ between groups. The mean change in PACC5Abridged from baseline to 24‐weeks was 0.28 for CMBAS, and 0.22 for HSMP (pooled baseline SD 0.72). The effect of participants’ repeated practice on the PACC5Abridged was non‐significant, ruling out retest effects as a substantive explanation for results. Amongst the PACC5Abridged constituent tests, significant improvement was observed in the RAVLT and WAIS‐IV Coding.ConclusionThis clinical trial evaluated the effect of two 8‐week non‐pharmacological interventions on objective cognitive performance in SCD. Scores on a composite measure of early Alzheimer’s disease related cognitive dysfunction improved in both arms, even after accounting for practice effects. These results paralleled those of the primary outcome measure (trait anxiety), for which scores also improved in both arms. This work adds to the growing body of evidence that non‐pharmacological interventions can impact cognition in individuals at increased risk of dementia.