Cognitive Interventions for Cognitively Healthy, Mildly Impaired, and Mixed Samples of Older Adults: A Systematic Review and Meta-Analysis of Randomized-Controlled Trials

Abstract

Cognitive interventions may improve cognition, delay age-related cognitive declines, and improve quality of life for older adults. The current meta-analysis was conducted to update and expand previous work on the efficacy of cognitive interventions for older adults and to examine the impact of key demographic and methodological variables. EBSCOhost and Embase online databases and reference lists were searched to identify relevant randomized-controlled trials (RCTs) of cognitive interventions for cognitively healthy or mildly impaired (MCI) older adults (60+ years). Interventions trained a single cognitive domain (e.g., memory) or were multi-domain training, and outcomes were assessed immediately post-intervention using standard neuropsychological tests. In total, 279 effects from 97 studies were pooled based on a random-effects model and expressed as Hedges' g (unbiased). Overall, results indicated that cognitive interventions produce a small, but significant, improvement in the cognitive functioning of older adults, relative to active and passive control groups (g = 0.298, p < .001, 95% CI = 0.248-0.347). These results were confirmed using multi-level analyses adjusting for nesting of effect sizes within studies (g = 0.362, p < .001, 95% CI = 0.275, 0.449). Age, education, and cognitive status (healthy vs. MCI) were not significant moderators. Working memory interventions proved most effective (g = 0.479), though memory, processing speed, and multi-domain interventions also significantly improved cognition. Effects were larger for directly trained outcomes but were also significant for non-trained outcomes (i.e., "transfer effects"). Implications for future research and clinical practice are discussed. This project was pre-registered with PROSPERO (#42016038386).

Effectiveness of executive function training on mental set shifting, working memory and inhibition in healthy older adults: A double‐blind randomized controlled trials

“…Previous studies have noted that process-based training yields superior results compared with the other two types and also have resulted in promising transfer of training in participants up to very old age (Brehmer, Westerberg, & B€ ackman, 2012;Karbach & Verhaeghen, 2014;Zinke et al, 2014). According to the Oxford Centre for Evidenced-Based Medicine's criteria, the quality of evidence for previous clinical trials of executive function-related training was range from grade 1A to grade 1B (Chapman et al, 2013;Chiu et al, 2017;Mewborn, Lindbergh, & Miller, 2017;OCEBM Levels of Evidence Working Group, 2011). Therefore, the executive function-related training may be effective to improve older adults' cognitive-related functions.…”

Cognition-oriented treatments for older adults: A systematic overview of systematic reviews

“…Five reviews were classified as a mixed population, three included individuals with MCI and dementia (Hoefler, 2016;Kurz, Leucht, & Lautenschlager, 2011;Yang et al, 2018), one stated that they looked at participants without dementia (Floyd & Scogin, 1997) and one did not specify cognitive status (Pinquart & Sörensen, 2001). Four reviews synthesized pooled effects for more than one population: two reviews reported metaanalytical results for healthy older adults and MCI (Martin, Clare, Altgassen, Cameron, & Zehnder, 2011;Mewborn, Lindbergh, & Stephen Miller, 2017), one reported results for healthy older adults and dementia (Karr, Areshenkoff, Rast, & Garcia-Barrera, 2014), and one focused on individuals with MCI and dementia (Hill et al, 2017).…”

“…The mean effect estimate was 0.32 (0.05 to 0.59). Evidence from the two most comprehensive reviews with 'moderate confidence' ratings showed a small and significant effect in favour of CT on overall cognitive functioning; Lampit et al (2014) synthesized the results of 51 trials of computerized CT and reported an effect size of Hedge's g 0.22 (0.15 to 0.29) and Mewborn et al (2017) pooled the results of 48 trials with an overall effect size of Hedge's g 0.31 (0.24 to 0.39). In all, 15 of 19 reviews showed a significant intervention effect on objective cognitive outcomes ( Fig.…”

Speed‐of‐Processing Training in Assisted and Independent Living: A Randomized Controlled Trial

“…[11][12][13][14][15][16][17] For example, using data from 97 randomized controlled trials (RCTs) examining a variety of cognitive training interventions in cognitively healthy adults and those with mild cognitive impairment (MCI) aged 60 and older, a Hedges' g of 0.30 (p<.001) that neither age, education, nor cognitive status significantly moderated was reported. 15 Using data from 17 RCTs in older adults with MCI, a Hedges' g of 0.35 (p<.001) was reported. 16 Focusing solely on speed-ofprocessing training (SOPT), a review of 17 RCTs 17 reported a Cohen's d of 0.71 (p<.001) on the targeted proximal outcome (useful field of view (UFOV)), 18,19 as well as transfer to real-world tasks including Cohen's d s of 0.27 (p<.001) on IADLs, 0.36 (p5.04) on driving mobility, and 0.21 (p5.04) on well-being.…”